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Om namo venkatesaya namah

Safety aspects in operation and maintenance of reactor vessels and kettles

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Introduction about the organization Basis of selection of project & Scope and objectives of the project work Safety Policy, Safety rules and guidelines Brief manufacturing process and hazardous raw materials used for process and properties Basic design aspects and types of reactors vessels, kettles and its maintenance Continuous stirred tank reactor Plug Flow reactor Semi batch reactor Catalytic reactor Centrifuge Drier ANFs (Agitated Nutch Filters) (pressure and with out pressure) Hazards associated with chemical manufacturing industries Static electricity Fire Explosion Release of toxic gases Health Hazards Safety aspects in operation and maintenance of reactors vessels and kettles Process control Explosion High Pressure operations Run away reactions Exothermic reactions and endothermic reactions Release of Toxic gases Health hazards at work places Chemical storage and transportation Material handling Fire safety Electrical safety Personnel safety (Personnel Protective Equipments) Ventilation Inertisation Machine guarding

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Electrical zoning House keeping IS color coding for material transfer lines Periodical maintenance Motivational activities Safety training and administrative controls Hazardous reactions carried out in reactors and kettles Sulphonation Oxidation Hydrogenation Hazard identification and control techniques and check lists Management of Change Risk Assessment HARA reports HAZOP studies Safety Audits MSDS Safety equipments and management systems Rupture disks Pressure relieve valves Safety Valves Explosion vents Safety Interlocks Calibration of safety equipments work permit system Statutory obligations safety instruments and gas monitors Role of Maintenance in the operation of reactors and kettles Preventive maintenance schedules and check lists for Reactors Tray driers Centrifuges ANFs (Agitated Nutch Filters) Emergency control measures Emergency handling techniques Accident investigation and reporting

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Observations and Recommendations for safe operation of reactors and vessels Conclusion of the project work References

Introduction about the organization

Deepak Nitrite Ltd., the Flagship Company of Deepak Group, is one of India's leading manufacturers of organic, inorganic, fine and specialty chemicals. The Deepak saga began way back in the 1960s when the group's visionary Chairman, Shri C. K. Mehta, established a trading enterprise in chemicals. In 1970 when the Indian economy was still under the License Raj, he decided to set up a plant based on indigenous technology to manufacture the two vital import substitutes: Sodium Nitrite and Sodium Nitrate The company diversified into manufacturing of Organic intermediates through its in-house expertise, strategic acquisitions and technological collaborations with world leaders. Deepak Nitrite today is a multi-product and multi-location company with a unique advantage of backward integration up to natural growth through its Group Company, Deepak Fertilizers and Petrochemicals Corporation Limited. With its wide range of products, rigorous adherence to quality parameters and deep understanding of user-industry needs, Deepak Nitrite is the preferred supplier of a host of leading companies in India, US, Europe and Far East, across a broad spectrum of industries like textiles, Pharmaceuticals, rubber, agrochemical, paints, dyes, explosives, glass, paper, cosmetics etc. All the manufacturing divisions of DNL are ISO 9001:2000, ISO 14001:2004 certified and the company also has an "EXPORT HOUSE" status. DNL is committed to take good care of Employees health and safety, environment and the community around it. A unique practice followed by the company is that at the product development stage itself, microbiologists work in tandem with the R&D team to develop environment-friendly solutions. Continuous monitoring of effluent treatment facilities in all manufacturing units ensures that all statutory requirements are adhered to. Process development is carried out with special emphasis on minimizing byproducts as well as putting them for commercial use.

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Basis of selection of project
In the present global industrial scenario, for any industry to be successful, it is essential to inculcate safety culture, consciousness in health and environment aspects in each personnel of an organization The significance of Safety & Health in chemical industries has been a vital issue in achieving productivity and an edge in the competitive world Safety is becoming an increasingly important activity in the chemical industry. This is due to several recent significant chemical accidents, increasing public awareness and skyrocketing liability and accident costs. The purpose of this project “Safety Aspects in operation and Maintenance of rector vessels and kettles” is to provide recommendations on meeting the safety requirements for core safety management in reactor vessels and kettles, on the basis of international good practices. This project addresses those aspects of core management activities that should be performed in order to allow optimum reactor core safe operation and reactor utilization for experiments, without compromising the limits imposed by the design safety considerations relating to chemical manufacturing and the reactor as a whole. All practical efforts must be made to prevent and mitigate chemical accidents.” This principle states that: “The most harmful consequences arising from facilities and activities have come from the loss of control over the reaction in rectors and kettles” The scope of this project includes guidance on personnel safety, operational safety, equipment safety, safe operating procedures, applicable regulatory standards, storage and

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handling of chemicals, transport safety or safety precautions for transport beyond the site or the off-site storage (bulk storage) and over all safety aspects in rectors vessels and kettles

Occupational Health and Safety Policy
Health and Safety as an integral part of manufacturing activities, is one of the prime concerns of the Management. To express this concern, the Management has defined the policy as follows, The Company will, 1. Consider all safety aspects at the design stage, installation of new plant & machinery as well as during introduction of process modification. 2. Provide the necessary organizational set up for implementation of the policy 3. Maintain all plants, machinery and equipment in proper working conditions in order to ensure safety of the plant and the operating people. 4. Identify possible accident hazards associated with the handling of raw materials, intermediates and finished products and the processing and operations carried out in company premises. 5. Take appropriate measures to ensure safe working conditions and protection against identified accident / health hazards, in order to minimize the risk of injury to employees and to the people in vicinity. 6. Arrange to provide necessary training on safety matters and also in use of personal protective and fire fighting equipment to all the employees (including contractor’s employees), so that they can work safely. 7. Develop emergency procedures and arrange periodic rehearsals to familiarize the employees and to assess their preparedness. 8. Comply with all the statutory requirements with respect to Health, Safety and Environment. 9. Communicate the policy to all employees, highlighting management’s determined role to maintain high standards of health and safety of the employees. 10. Management believes that Safety is every ones responsibility. Date 1st July,2010 Sd/Chief Executive Officer 6

SAFETY PRINCIPLES
Manufacture of specialty chemicals involves handling large quantities of chemicals, Acids, and Solvents and different types of power driven machines which if proper care is not taken by persons concerned in observing safe working practices, can be hazardous. Accidents are caused by either unsafe acts or unsafe conditions or both and they can be prevented by correction of the unsafe acts and conditions. In order to avoid mishaps and accidents, it is essential that the employees working in production department must be aware of all the important properties of the material and the follow all safety precautions while working. This safety manual has been complied with the object of providing the staff members with the information regarding the safety precautions, which they should take to prevent accidents and injury. Some of the safety precautions may appear, at times, irksome and for many simple jobs it may seem to be a waste of time and effort to wear personal protective equipment. There should, however be no relaxation in observing safety practices. 1. Deepak Nitrite Limited supports and endorses the broad purposes and goals of the Factories Act 1948 and AP Factory Rules 1950. In keeping with existing practices it shall be our policy to comply with Government regulations issued under it in all operations to ensure safety in the work place and prevention of health hazards in and around all plants and laboratories 2. It is a fundamental principle that no operation shall be carried out unless and adequate degree of safety can be insured. 3. Deepak Nitrite Limited activities involving research and development and production will emphasize safety in all documentation pertaining to the operations to be performed. 4. The safety of personnel and property is a prime responsibility of managers and supervisors.

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During the research, development and operation and maintenance of factories, plants and installations. The managers and supervisors concerned are duty bound to take all reasonable measures to ensure that conditions do not arise which might cause injury to or adversely affect the health and well being of any person, or damage to or destruction of property. The decisions necessary to achieve this level of safety are an important part of every manager and supervisor’s area of competence and responsibility.

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As per as the general state of knowledge allows every manager and supervisor must be fully conversant with the properties and behavior of the materials as will as with the capabilities in limitations of the machines and the equipment in use within her/his area of responsibility. Where this is not the case, assistance is provided by specialists, who take over responsibility in case where directions and decisions must be based on their knowledge and experience.

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Every manager and supervisor is responsible for the observance of all laws, regulations, directions and guidelines governing her/his area of responsibility as well as of all accepted rules of technology applying to the operations being carried out under her/his supervision.

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Every manager and supervisor must constantly bear in mind the varying levels of knowledge and experience of subordinates, and that the demands which he or she may make on them may be limited. Arrangements must be made for the technical, organizational and staffing measures necessary to ensure safe methods of working within her or his area of responsibility.

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Every employee must observe the safety regulations and instructions applicable to the work place. Each person bears the responsibility for safety to the best of his/her knowledge and ability.

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General directions and guidelines on safety within Deepak Nitrite Limited are laid down by the Safety Department. It also advises managers, supervisors and employees on matters of safety whenever requested. It aims to achieve a safety standard which is as uniform as possible throughout Deepak Nitrite Limited and which conforms with normal practice in the industry.

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GENERAL SAFE PRACTICES FOR ALL EMPLOYEES
The basic principles of safety at work are the elimination of conditions that could cause accidents and developing the habits of working in a safe and systematic manner. In the following pages are given the ground rules of safety and codes of conduct adherence to, which will go a long way towards eliminating accidents. 1. Deepak Nitrite Limited does not expect you to take unnecessary chances or to work under hazardous conditions. Report unsafe conditions to your BLOCK IN CHARGE. Do not use unsafe tools or equipment. 2. 3. 4. 5. 6. 7. 8. Your suggestions for improving safe conditions are always welcome and are solicited Before starting any job, be sure that you receive and understand the instruction of your supervisor. Ask questions, he/she is there to help you do the job right. Keep your work place neat and clean. Have a definite place for tools and other equipment, and keep them there when not in use. Don’t leave any objects (pipes, paper, tools, etc.) on the floor where they could cause slips or falls Dot not distract or interfere in any way with a person performing his/her job. Smoking in forbidden areas is contrary to law and constitutes grounds for disciplinary action. It can create serious fire hazard and explosion. Before working in another area or department, check with the area supervisor and be sure that you know the locations of exits, emergency showers, eye fountains, fire alarms, phones and extinguishers. 9. 10. 11. Keep aisles and passageways clear. Stand aside while vehicles pass or unload. Always wear approved type of eye protection when performing operations involving potential hazards to the eye. If you receive an injury, no matter how slight, obtain permission from your Shift in charge and report at once to the Occupational Health Centre. Slight injuries can become infected through neglect. 12. 13. 14. Running in any part of the plant is prohibited expected in an emergency. Short cuts must never be taken through or over dangerous places. Do not operate any equipment unless you are familiar with its operation and have been authorized to do so.

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15. 16.

Obey all warning signs and tags. Their purpose is to warn you of hazards. Do not allow chemicals to contact your skin. If you work with chemicals, shower at end of shit or immediately if liquids or dusts are spilled on your clothing. DO NOT PUT ON CONTAMINATED CLOTHING OR SHOES.

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Vehicles, lift trucks, etc. must not be operated except by AUTHORIZED OPERATORS. Capacities must not be exceeded. Trucks or other vehicles being loaded must be properly checked. When necessary, loads must be secured to the vehicle by means of chains, cables, chocks, etc. Puddles or droppings of Oil, grease, water, or other liquids should be removed by mopping up and covering with oil absorbent until the floor is dry. Drippings on the floor should be prevented by eliminating the cause or by placing drip pans in position until the cause has been eliminated.

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Any accident that did or could cause serious damage to equipment or injury to persons must be reported to your Shift in charge or to the safety department so that preventive action can be taken in all locations.

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Immediately flush chemical burns with water for a minimum of fifteen minutes

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Brief manufacturing process with process flow charts
Brief Manufacturing Process: Stage I : Para Nitro Toluene (PNT) is sulphonated with Oleum 30% and quenched into water, cooled and crystallized. The crystallized sulphonated mass is filtered through agitated nutch filter to separate the spent dilute Sulphuric acid from the PNTSA wet cake. The PNTSA wet cake is dissolved in water and 35% solution of PNTSA is transported to Unit-II through a road tanker for consumption to DNSDA manufacture. The spent Sulphuric acid is generated during Sulphonation is partly meeting the requirements of acidification / neutralization in the in house manufacture operations. The rest of the spent Sulphuric acid is being sold to phosphoric fertilizers industry / alum industry and hence spent Sulphuric acid is a valuable by-product and helping in conserving non-renewable resource namely Sulphur.

Flow Chart of process

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PNT
Oleum 30%

Air

Sulphonation of PNT
SO3 traces Packed column scrubber

Water

Drowning of Sulphonated mass

Scrubber liquor to wastewater

Filtration through ANF

PNTSA solution

Spent H2SO4 (byproduct) for reuse / sale

Loading into road tankers and dispatch to Unit-II

Stage-II • The Raw material PNTSA in solution form is received from Units - I, and III. After processing, in Unit-II the output DNSDA in solution form is sent to respective units to meet their requirements for manufacture of DAS. • • • Para Nitro Toluene Ortho Sulphonic Acid (PNTSA), Caustic Lye, and PNTS ML’s / Spent H2SO4 are the raw materials used. After neutralization, oxidation is carried out and PNTSA is converted into DNSDA. Evaporation, crystallization and filtration are carried out to separate DNSDA wet cake from DNSDA mother liquor. DNSDA cake and Mother Liquor are separated. DNSDA is dissolved in water and made solution and sent to Unit-I and Unit-III. • Part of DAS mother liquor generated at Unit-I & III is fed to Sodium Sulphate decahydrate recovery plant to recover Sodium Sulphate deca-hydrate. The Sodium Sulphate deca-hydrate is treated with carbon to remove color impurities through 12

clarification. The filtrate is fed to SRCP to recover pure Sodium Sulphate and sold. The water generated from SRCP is used to dissolve crude Sodium Sulphate as mentioned above. The concentrate generated during deca-hydrate preparation is fed to DNSDA –ML evaporator along with DNSDA mother liquor. • Thus, in the process, water and Sodium Sulphate are recovered and no wastewater is generated. Hence Unit-II is a zero discharge unit in Deepak Nitrite Limited Flow Chart
Air Water PNTSA Soda ash NaOH, Catalyst Air Spent H2SO4 Neutralization Oxidation Condensed mist Air Mist Collector

Concentration by evaporation (TEE)

Recovered water

Spent H2SO4

Crystallization

Filtration Filtrate (ML)
DNSDA wet cake Preparation of DNSDA solution by dissolving the case in water Loading into road tankers and dispatch to Unit-I & III

Water

DNSDA ML evaporator

TSDF

Stage III: 13

DNSDA solution received from Unit-II is reduced with water and Iron powder in presence of acetic acid as catalyst. The reduced mass is neutralized with sodium hydroxide and filtered to separate iron oxide from DAS solution. Iron oxide washed with water and combined with DAS solution. The combined DAS solution is precipitated with spent dilute Sulphuric acid generated in the Sulphonation process. The DAS precipitate is filtered through Agitated Nutch Filter (ANF). The mother liquor (ML) is collected separately in acid & alkali poof brick lined storage tanks. The DAS cake is washed with water and the wash liquor collected separately in acid & alkali poof brick lined storage tanks at above ground level. The entire quantity of mother liquor is sent to Unit-II for recovery of sodium sulphate deca –hydrate for which facilities are available. DAS wet cake is taken out from ANF, dried in Spin Flash Dryer (SFD) and packed for sale.

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Flow Chart
Air Water PNTSA Soda ash NaOH, Catalyst Air Spent H2SO4 Neutralization Oxidation Condensed mist Air Mist Collector

Concentration by evaporation (TEE)

Recovered water

Spent H2SO4

Crystallization

Filtration Filtrate (ML)
DNSDA wet cake Preparation of DNSDA solution by dissolving the case in water Loading into road tankers and dispatch to Unit-I & III

Water

DNSDA ML evaporator

TSDF

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Safety aspects in operation and maintenance of reactors Design requirements of reactor
The Batch reactor is the generic term for a type of vessel widely used in the process industries. Its name is something of a misnomer since vessels of this type are used for a variety of process operations such as solids dissolution, product mixing, chemical reactions, batch distillation, crystallization, liquid/liquid extraction and polymerization. In some cases, they are not referred to as reactors but have a name which reflects the role they perform (such as crystallizer, or bio reactor). A typical batch reactor consists of a tank with an agitator and integral heating/cooling system. These vessels may vary in size from less than 1 litre to more than 15,000 litres. They are usually fabricated in steel, stainless steel, glass lined steel, glass or exotic alloy. Liquids and solids are usually charged via connections in the top cover of the reactor. Vapors and gases also discharge through connections in the top. Liquids are usually discharged out of the bottom. The advantages of the batch reactor lie with its versatility. A single vessel can carry out a sequence of different operations without the need to break containment. This is particularly useful when processing, toxic or highly potent compounds.

Agitation
The usual agitator arrangement is a centrally mounted driveshaft with an overhead drive unit. Impeller blades are mounted on the shaft. A wide variety of blade designs are used and typically the blades cover about two thirds of the diameter of the reactor. Where viscous products are handled, anchor shaped paddles are often used which have a close clearance between the blade and the vessel walls. Most batch reactors also use baffles. These are stationary blades which break up flow caused by the rotating agitator. These may be fixed to the vessel cover or mounted on the side walls.

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Despite significant improvements in agitator blade and baffle design, mixing in large batch reactors is ultimately constrained by the amount of energy that can be applied. On large vessels, mixing energies of more than 5 Watts per litre can put an unacceptable burden on the cooling system. High agitator loads can also create shaft stability problems. Where mixing is a critical parameter, the batch reactor is not the ideal solution. Much higher mixing rates can be achieved by using smaller flowing systems with high speed agitators, ultrasonic mixing or static mixers.

Heating and cooling systems
Products within batch reactors usually liberate or absorb heat during processing. Even the action of stirring stored liquids generates heat. In order to hold the reactor contents at the desired temperature, heat has to be added or removed by a cooling jacket or cooling pipe. Heating/cooling coils or external jackets are used for heating and cooling batch reactors. Heat transfer fluid passes through the jacket or coils to add or remove heat. Within the chemical and pharmaceutical industries, external cooling jackets are generally preferred as they make the vessel easier to clean. The performance of these jackets can be defined by 3 parameters:
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Response time to modify the jacket temperature Uniformity of jacket temperature Stability of jacket temperature

It can be argued that heat transfer coefficient is also an important parameter. It has to be recognized however that large batch reactors with external cooling jackets have severe heat transfer constraints by virtue of design. It is difficult to achieve better than 100 Watts/litre even with ideal heat transfer conditions. By contrast, continuous reactors can deliver cooling capacities in excess of 10,000 W/litre. For processes with very high heat loads, there are better solutions than batch reactors.

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Fast temperature control response and uniform jacket heating and cooling is particularly important for crystallization processes or operations where the product or process is very temperature sensitive. There are several types of batch reactor cooling jackets:

Single external jacket

Batch reactor with single external cooling jacket The single jacket design consists of an outer jacket which surrounds the vessel. Heat transfer fluid flows around the jacket and is injected at high velocity via nozzles. The temperature in the jacket is regulated to control heating or cooling. The single jacket is probably the oldest design of external cooling jacket. Despite being a tried and tested solution, it has some limitations. On large vessels, it can take many minutes to adjust the temperature of the fluid in the cooling jacket. This results in sluggish temperature control. The distribution of heat transfer fluid is also far from ideal and the heating or cooling tends to vary between the side walls and bottom dish. Another issue to consider is the inlet temperature of the heat transfer fluid which can oscillate (in response to the temperature control valve) over a wide temperature range to cause hot or cold spots at the jacket inlet points.

Half coil jacket

Batch reactor with half coil jacket

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The half coil jacket is made by welding a half pipe around the outside of the vessel to create a semi circular flow channel. The heat transfer fluid passes through the channel in a plug flow fashion. A large reactor may use several coils to deliver the heat transfer fluid. Like the single jacket, the temperature in the jacket is regulated to control heating or cooling. The plug flow characteristics of a half coil jacket permits faster displacement of the heat transfer fluid in the jacket (typically less than 60 seconds). This is desirable for good temperature control. It also provides good distribution of heat transfer fluid which avoids the problems of non uniform heating or cooling between the side walls and bottom dish. Like the single jacket design however the inlet heat transfer fluid is also vulnerable to large oscillations (in response to the temperature control valve) in temperature.

Constant flux cooling jacket

Batch reactor with constant flux (Coflux) jacket The constant flux cooling jacket is a relatively recent development. It is not a single jacket but has a series of 20 or more small jacket elements. The temperature control valve operates by opening and closing these channels as required. By varying the heat transfer area in this way, the process temperature can be regulated without altering the jacket temperature. The constant flux jacket has very fast temperature control response (typically less than 5 seconds) due to the short length of the flow channels and high velocity of the heat transfer fluid. Like the half coil jacket the heating/cooling flux is uniform. Because the jacket operates at substantially constant temperature however the inlet temperature oscillations seen in other jackets are absent. An unusual feature of this type jacket is that process heat can be measured very sensitively. This allows the user to monitor the rate of reaction for detecting end points, controlling addition rates, controlling crystallization etc.

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Types and design basis of rectors

In chemical engineering, chemical reactors are vessels designed to contain chemical reactions. The design of a chemical reactor deals with multiple aspects of chemical engineering. Chemical engineers design reactors to maximize net present value for the given reaction. Designers ensure that the reaction proceeds with the highest efficiency towards the desired output product, producing the highest yield of product while requiring the least amount of money to purchase and operate. Normal operating expenses include energy input, energy removal, raw material costs, labor, etc. Energy changes can come in the form of heating or cooling, pumping to increase pressure, frictional pressure loss (such as pressure drop across a 90o elbow or an orifice plate), agitation, etc. There are two main basic vessel types:
• •

A tank A pipe

Both types can be used as continuous reactors or batch reactors. Most commonly, reactors are run at steady-state, but can also be operated in a transient state. When a reactor is first brought back into operation (after maintenance or inoperation) it would be considered to be in a transient state, where key process variables change with time. Both types of reactors may also accommodate one or more solids (reagents, catalyst, or inert materials), but the reagents and products are typically liquids and gases.

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There are three main basic models used to estimate the most important process variables of different chemical reactors:
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batch reactor model (batch), continuous stirred-tank reactor model (CSTR), and Plug flow reactor model (PFR).

Furthermore, catalytic reactors require separate treatment, whether they are batch, CST, or PF reactors, as the many assumptions of the simpler models are not valid. Key process variables include
• • • • • •

Residence time (τ, lower case Greek tau) Volume (V) Temperature (T) Pressure (P) Concentrations of chemical species (C1, C2, C3, ... Cn) Heat transfer coefficients (h, U)

CSTR (Continuous Stirred-Tank Reactor)

In a CSTR, one or more fluid reagents are introduced into a tank reactor equipped with an impeller while the reactor effluent is removed. The impeller stirs the reagents to ensure proper mixing. Simply dividing the volume of the tank by the average volumetric flow rate through the tank gives the residence time, or the average amount of time a discrete quantity of

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reagent spends inside the tank. Using chemical kinetics, the reaction's expected percent completion can be calculated. Some important aspects of the CSTR:


At steady-state, the flow rate in must equal the mass flow rate out, otherwise the tank will overflow or go empty (transient state). While the reactor is in a transient state the model equation must be derived from the differential mass and energy balances.



The reaction proceeds at the reaction rate associated with the final (output) concentration. Often, it is economically beneficial to operate several CSTRs in series. This allows, for example, the first CSTR to operate at a higher reagent concentration and therefore a higher reaction rate. In these cases, the sizes of the reactors may be varied in order to minimize the total capital investment required to implement the process.





It can be seen that an infinite number of infinitely small CSTRs operating in series would be equivalent to a PFR.

The behavior of a CSTR is often approximated or modeled by that of a Continuous Ideally Stirred-Tank Reactor (CISTR). All calculations performed with CISTRs assume perfect mixing. If the residence time is 5-10 times the mixing time, this approximation is valid for engineering purposes. The CISTR model is often used to simplify engineering calculations and can be used to describe research reactors. In practice it can only be approached, in particular in industrial size reactors.

PFR (Plug Flow Reactor)
In a PFR, one or more fluid reagents are pumped through a pipe or tube. The chemical reaction proceeds as the reagents travel through the PFR. In this type of reactor, the changing reaction rate creates a gradient with respect to distance traversed; at the inlet to the PFR the rate is very high, but as the concentrations of the reagents decrease and the concentration of the product(s) increases the reaction rate slows. Some important aspects of the PFR:


All calculations performed with PFRs assume no upstream or downstream mixing, as implied by the term "plug flow".

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Reagents may be introduced into the PFR at locations in the reactor other than the inlet. In this way, a higher efficiency may be obtained, or the size and cost of the PFR may be reduced.



A PFR typically has a higher efficiency than a CSTR of the same volume. That is, given the same space-time, a reaction will proceed to a higher percentage completion in a PFR than in a CSTR.

For most chemical reactions, it is impossible for the reaction to proceed to 100% completion. The rate of reaction decreases as the percent completion increases until the point where the system reaches dynamic equilibrium (no net reaction, or change in chemical species occurs). The equilibrium point for most systems is less than 100% complete. For this reason a separation process, such as distillation, often follows a chemical reactor in order to separate any remaining reagents or byproducts from the desired product. These reagents may sometimes be reused at the beginning of the process, such as in the Haber process. Continuous oscillatory baffled reactor (COBR) is a tubular plug flow reactor. The mixing in COBR is achieved by the combination of fluid oscillation and orifice baffles, allowing plug flow to be achieved under laminar flow conditions with the net flow Reynolds number just about 100.

Semi-batch reactor
A semi-batch reactor is operated with both continuous and batch inputs and outputs. A fermenter, for example, is loaded with a batch, which constantly produces carbon dioxide, which has to be removed continuously. Analogously, driving a reaction of gas with a liquid is

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usually difficult, since the gas bubbles off. Therefore, a continuous feed of gas is injected into the batch of a liquid. An example of such a reaction is chlorination.

Catalytic reactor
Although catalytic reactors are often implemented as plug flow reactors, their analysis requires more complicated treatment. The rate of a catalytic reaction is proportional to the amount of catalyst the reagents contact. With a solid phase catalyst and fluid phase reagents, this is proportional to the exposed area, efficiency of diffusion of reagents in and products out, and turbulent mixing or lack thereof. Perfect mixing cannot be assumed. Furthermore, a catalytic reaction pathway is often multi-step with intermediates that are chemically bound to the catalyst; and as the chemical binding to the catalyst is also a chemical reaction, it may affect the kinetics. The behavior of the catalyst is also a consideration. Particularly in high-temperature petrochemical processes, catalysts are deactivated by sintering, coking, and similar processes. A common example of a catalytic reactor is the catalytic converter following an engine.

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Continuous and batch operation
Chemical processes may be run in continuous or batch operation. In batch operation, production occurs in time-sequential steps in batches. A batch of feedstock(s) is fed into a process or unit, then the chemical process takes place, then the product(s) and any other outputs are removed. Such batch production may be repeated over again and again with new batches of feedstock. Batch operation is commonly used in smaller scale plants such as pharmaceutical or specialty chemicals production. In continuous operation, all steps are ongoing continuously in time. During usual continuous operation, the feeding and product removal are ongoing streams of moving material, which together with the process itself, all take place simultaneously and continuously. Chemical

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plants or units in continuous operation are usually in a steady state or approximate steady state. Steady state means that quantities related to the process do not change as time passes during operation. Such constant quantities include stream flow rates, heating or cooling rates, temperatures, pressures, and chemical compositions at every point (location). Continuous operation is more efficient in many large scale operations like petroleum refineries. It is possible for some units to operate continuously and others be in batch operation in a chemical plant; for example, see Continuous distillation and Batch distillation. The amount of primary feedstock or product per unit of time which a plant or unit can process is referred to as the capacity of that plant or unit. For examples: the capacity of an oil refinery may be given in terms of barrels of crude oil refined per day; alternatively chemical plant capacity may be given in tons of product produced per day. In actual daily operation, a plant (or unit) will operate at a percentage of its full capacity.

Glass lined reactor

Design parameters for reactors
Autoclaves (pressure vessel)
Size 2 Litres to 100 Litres

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Design Pressure Design Temperature Material of Construction Heating Options Heating System Agitator Drive Variable Speed Safety Shaft Seal Bottom outlet Fasteners

up to 100 kg / cm2 up to 300 °C Carbon steel, Alloy Steel, Monel, Nickel. Jacket, Limpet Coil, Internal Coil, Electrical Heater Oil Heating, Electrical System complete with controls FLP/TEFC/Pneumatic Motors Stepless Infinitely variable Rupture disc/spring loaaded safety valve Mechanical seal or stuffing box with cooling arrangement Flush bottom valve High tensile A 193 Gr.B7/A 194 Gr.2H

2. High Pressure Reactors
Size Design Pressure Design Temperature Material of Construction Code of Construction Heating / Cooling Options Agitator Drive Safety Shaft Seal Fasteners 100 Litres to 20000 Litres up to 100 kg / cm2 Thickness up to 56 mm up to 300 °C Carbon steel, S.S (Gr. SS 316, SS 304, SS 310, SS 321), Monel, Nickel, etc. ASME / BS / IS / DIN Jacket, Limpet Coil, Internal Coil, Electrical Heater (only for small reactor) FLP / TEFC / Pneumatic / Hydraulic Motors Rupture disc / spring loaded safety valve Mechanical seals or stuffing box with cooling arrangement High tensile A 193 Gr.B7/A 194 Gr.2H

Centrifuge
A centrifuge is a piece of equipment, generally driven by an electric motor (some older models were spun by hand), that puts an object in rotation around a fixed axis, applying a force perpendicular to the axis. The centrifuge works using the sedimentation principle, where the centripetal acceleration causes more dense substances to separate out along the radial direction (the bottom of the tube). By the same token, lighter objects will tend to move to the top (of the tube; in the rotating picture, move to the centre).

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In the picture shown, the rotating unit, called the rotor, has fixed holes drilled at an angle (to the vertical). Test tubes are placed in these slots and the rotor is spun. As the centrifugal force is in the horizontal plane and the tubes are fixed at an angle, the particles have to travel only a little distance before they hit the wall and drop down to the bottom. These angle rotors are very popular in the lab for routine use.

Vertical batch centrifuge

Decanter centrifuge

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Batch Centrifuge

Peeler centrifuge

Theory
Protocols for centrifugation typically specify the amount of acceleration to be applied to the sample, rather than specifying a rotational speed such as revolutions per minute. This distinction is important because two rotors with different diameters running at the same rotational speed will subject samples to different accelerations. During circular motion the acceleration is the product of the radius and the square of the angular velocity and it is traditionally named "relative centrifugal force" (RCF).

Types of centrifuges
There are at least five types of centrifuge: ⇒ preparative centrifuge ⇒ analytical centrifuge ⇒ angle fixed centrifuge ⇒ swing head centrifuge ⇒ haematocrit centrifuge Industrial centrifuges may otherwise be classified according to the type of separation of the high density fraction from the low density one :

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Screen centrifuges, where the centrifugal acceleration allows the liquid to pass through a screen of some sort, through which the solids cannot go (due to granulometry larger than the screen gap or due to agglomeration). Common types are :
o o

Pusher centrifuges Peeler centrifuges



Decanter centrifuges, in which there is no physical separation between the solid and liquid phase, rather an accelerated settling due to centrifugal acceleration. Common types are :
o o

Solid bowl centrifuges Conical plate centrifuges

Dryers
The Drying ovens are normally available with choice of heating mode, as electrically heated / steam heated & thermic fluid heated.. In electrically heated model, digital temperature controller provided with digital timer to facilitate working day and night. In steam & thermic fluid heated model, digital temperature indicator is provided with digital timer , but the temperature controller is not supplied with the machine.

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Air Circulation : A highly effective recirculating air system is provided in the Tray Dryers. The heated air is recirculated with fresh air in selected proportions for optimum drying. The system is designed so that the materials at the top & the bottom dry simultaneously. Uniform air circulation, controlled temperature, sturdy construction and large working space are the valuables of the oven which is suitably designed to cover wide temperature range, loading and unloading is faster and simple. In higher capacities trays trolley rolls in and out of the chamber. For continuous operation a spare trolley can be had for loading while the drying cycle is taking place. Controlled Temperature & Time : Digital temperature controller with digital timer are supplied in Tray Dryers to facilitate working day and night. Option : Flame proof fittings and motor. S.S.304 / S.S. 316 Trays. Application : Tray Dryers are widely used in Pharmaceutical, food, chemicals and other industries.

Different types of driers photos are given below

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Fluid bed dryer

Spin splash drier

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Autoclave
An autoclave is a device to sterilize equipment and supplies by subjecting them to high pressure saturated steam at 121 °C or more, typically for 15-20 minutes depending on the size of the load and the contents. It was invented by Charles Chamberland in 1879, although a precursor known as the steam digester was created by Denis Papin in 1679. The name comes from Greek auto, ultimately meaning self, and Latin clavis meaning key — a self-locking device.

Agitated Nutch Filter
Agitated Nutsche filter (ANF) is a filtration technique used in applications such as dye, paint, and pharmaceutical production[1] and waste water treatment.[2] Safety requirements and environmental concerns due to solvents evaporation led to development of this type of filter wherein filtration under vacuum or pressure can be carried out in closed vessels and solids can be discharged straightaway into drier. A typical unit consists of a dished vessel with a perforated plate. The entire vessel can be kept at desired temperature by using a limpet jacket, jacketed bottom dish & stirrer (blade & shaft) through which heat transfer media can flow. The vessel can be made completely leak proof for vacuum or pressure service.

A multipurpose agitator is the unique feature of this system. The agitator performs a number of operations through movement in axes both parallel and perpendicular to the shaft.


Slurry contents can be kept fluidized until most of the mother liquor is filtered through. When filtration is complete, the cake develops cracks causing upsets in the vacuum operation. This hinders removal of mother liquor. The agitator can be used to maintain a uniform cake.





The cake can be washed after filtration by reslurrying the cake.

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After washing, the mother liquor can be refiltered. The cake can then be discharged by lowering the agitator and rotating it in such a manner that it brings all the cake towards discharge port.

A typical unit consists of a dished vessel with a perforated plate. The entire vessel can be kept at desired temperature by using a limpet jacket, jacketed bottom dish & stirrer (blade & shaft) through which heat transfer media can flow. The vessel can be made completely leak proof for vacuum or pressure service.

Materials of Construction
Agitated Nutsche filters can be fabricated in materials like Hastelloy C-276, C-22, stainless steel, mild steel, and mild steel with rubber lining as per service requirements. Recently agitated Nutsche filters have been fabricated out of polypropylene fibre reinforced plastic (PPFRP).

Advantages
1. Vacuum or pressure filtration possible. 2. Inert gas atmosphere can be maintained. 3. Very high solvent recovery. 4. Considerable saving in manpower 5. Solvents are in closed systems, so no toxic vapors are let off in the atmosphere. 6. Personal safety is maintained and heat transfer surfaces can be provided to maintain filtration temperature.

Static electricity and control

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Static electricity is one of the most insidious sources of fire and explosion encountered in modern industry and with out static electricity it is not relevant to discuss any safety aspects in chemical manufacturing companies. It is by nature unpredictable and therefore difficult to detect. In some industry sectors it is viewed almost as a black art Static electricity is produced by pumping of materials or by any other means of motion, such as agitation. The movement separates positive and negative charges, which then accumulate in the liquid and the containment system (lines, tanks, drums etc). The charge on the containment system is dissipated quickly by earthing, but the charge in the liquid remains and is slowly dissipated, depending on the conductivity of the liquid. Static charges can accumulate in liquids with a conductivity of less than 50 Picosiemens/meter (pS/m). In such liquids, high potential differences can be created, that can discharge into powerful sparks capable of causing ignition of solvent vapours. Discharges can occur from insulated conductors (plant items, drums), bulk liquids, mists and insulating plastic materials.

Uncontrolled static electricity is a problem in many sectors of manufacturing industry but is of particular concern in operations where sensitive flammable materials are present. Fires and explosions attributable to static may actually be increasing in frequency due increased product purity and faster process speeds. With the right approach electrostatic ignition hazards can be identified and controlled. This fact sheet looks at the steps taken in a hazard assessment and the key parameters that need to be determined. There are five general conditions necessary for an electrostatic ignition hazard to be present: 1. 2. 3. Sensitive flammable atmosphere Generation of electrostatic charge Accumulation of charge

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4. 5.

Electrostatic discharge (ESD) Sufficient discharge energy

Generation of static electricity
The generation of electrostatic charge is intrinsic to many industrial operations. The rate of charge generation is notoriously difficult to predict, however, operations involving rapid and energetic movement and the contact and separation of surfaces will produce increased charging. Milling of powder, for example, will generate more charge than pouring. In industry charge generation mechanisms are as follows: The contact and separation of solid surfaces such as moving webs over rollers. The movement of personnel. The flow/movement of liquids. The production of mist or aerosols. The flow or movement of powders. Charging by induction in an electric field. Parameters influencing the levels of electrostatic potential generated are:  The nature of the material comprising the particulate.  Flow velocity.  Mass flow rate/density (kg/m3)  Particle size  Composition of duct walls.  Turbulence due to bends, constrictions etc.  Temperature and humidity. The amount of charge generated on a liquid flowing in a straight pipe is generally limited by three factors:

     

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  

The conductivity of the liquid The flow velocity The nature of the pipe wall Controlling/elimination of static electricity There are hosts of products, materials, and strategies for protection and static elimination. The would-be user can be easily overwhelmed by complexities of static control and the sometimes conflicting advice of product sales associates. As you wade through the sales pitches and product performance claims, stay focused on the goal of controlling static. First, most static control strategies can be reduced to simple terms.  If a material is conductive, then ground it.  If a material is insulative, remove it from the production area or make it conductive and ground it.  If it cannot be made conductive or remove it, then shield it.  Control the charge on people because people are the most common source of charge and ESD. The general idea is to remove sources of static. Insulative materials, when rubbed, accumulate static charge. Some insulators have a charge by their nature. Conductive materials can hold a charge only when they are not grounded. So by grounding them we remove any charge. When a source of static cannot be removed, a machine for example, a shield of conductive material (usually metal) can protect an area or products from the static charge. Shields work best when grounded. Secondly, understand that all static control products function in one of three ways.

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 Reduce charge accumulation. ('generation')  Provide a path for the static charge to move away from the electronics.(Grounding)  Shield the electronics from static fields or charges.

Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition. The flame is the visible portion of the fire and consists of glowing hot gases. If hot enough, the gases may become ionized to produce plasma. Depending on the substances alight, and any impurities outside, the color of the flame and the fire's intensity might vary. Fire in its most common form can result in conflagration, which has the potential to cause physical damage through burning. Fire is an important process that affects ecological systems 38

across the globe. The positive effects of fire include stimulating growth and maintaining various ecological systems. Fire has been used by humans for cooking, generating heat, signaling, and propulsion purposes. The negative effects of fire include decreased water purity, increased soil erosion, an increase in atmospheric pollutants and an increased hazard to human life.

Chemistry of fire

The fire tetrahedron Fires start when a flammable and/or a combustible material, in combination with a sufficient quantity of an oxidizer such as oxygen gas or another oxygen-rich compound (though nonoxygen oxidizers exist that can replace oxygen), is exposed to a source of heat or ambient temperature above the flash point for the fuel/oxidizer mix, and is able to sustain a rate of rapid oxidation that produces a chain reaction. This is commonly called the fire tetrahedron. Fire cannot exist without all of these elements in place and in the right proportions. For example, a flammable liquid will start burning only if the fuel and oxygen are in the right proportions. Some fuel-oxygen mixes may require a catalyst, a substance that is not directly involved in any chemical reaction during combustion, but which enables the reactants to combust more readily. Once ignited, a chain reaction must take place whereby fires can sustain their own heat by the further release of heat energy in the process of combustion and may propagate, provided there is a continuous supply of an oxidizer and fuel. Fire can be extinguished by removing any one of the elements of the fire tetrahedron. Consider a natural gas flame, such as from a stovetop burner. The fire can be extinguished by any of the following: 39

• •

turning off the gas supply, which removes the fuel source; covering the flame completely, which smothers the flame as the combustion both uses the available oxidizer (the oxygen in the air) and displaces it from the area around the flame with CO2;



application of water, which removes heat from the fire faster than the fire can produce it (similarly, blowing hard on a flame will displace the heat of the currently burning gas from its fuel source, to the same end), or



Application of a retardant chemical such as Halon to the flame, which retards the chemical reaction itself until the rate of combustion is too slow to maintain the chain reaction.

In contrast, fire is intensified by increasing the overall rate of combustion. Methods to do this include balancing the input of fuel and oxidizer to stoichiometric proportions, increasing fuel and oxidizer input in this balanced mix, increasing the ambient temperature so the fire's own heat is better able to sustain combustion, or providing a catalyst; a non-reactant medium in which the fuel and oxidizer can more readily react.

Fire triangle

The fire triangle. The fire triangle or combustion triangle is a simple model for understanding the ingredients necessary for most fires. The triangle illustrates a fire requires three elements: heat, fuel, and an oxidizing agent (usually oxygen). The fire is prevented or extinguished by removing any one of them. A fire naturally occurs when the elements are combined in the right mixture. Without sufficient heat, a fire cannot begin, and it cannot continue. Heat can be removed by the application of a substance which reduces the amount of heat available to the fire reaction. 40

This is often water, which requires heat for phase change from water to steam. Introducing sufficient quantities and types of powder or gas in the flame reduces the amount of heat available for the fire reaction in the same manner. Scraping embers from a burning structure also removes the heat source. Turning off the electricity in an electrical fire removes the ignition source. Without fuel, a fire will stop. Fuel can be removed naturally, as where the fire has consumed all the burnable fuel, or manually, by mechanically or chemically removing the fuel from the fire. Fuel separation is an important factor in wildland fire suppression, and is the basis for most major tactics, such as controlled burns. The fire stops because a lower concentration of fuel vapor in the flame leads to a decrease in energy release and a lower temperature. Removing the fuel thereby decreases the heat. Without sufficient oxygen, a fire cannot begin, and it cannot continue. With a decreased oxygen concentration, the combustion process slows. In most cases, there is plenty of air left when the fire goes out so this is commonly not a major factor.

Fire classes

Based on the combustible material involved, the fire can be classified. In the European Standard "Classification of fires" (EN 2:1992, in corporatiing amendment A1:2004), the fires are classified as:
• •

Class A fire: Ordinary combustibles such as wood, paper, carton, textile, and PVC; Class B fire: Flammable liquids and solids which can take a liquid form, such as benzene, gasoline, oil; Class C fire: Flammable gases, such as butane, propane, and natural gas; Class D fire: Combustible metals, such as iron, aluminum, sodium, and magnesium; Class F fire: Cooking media, such as oils and fats, in cooking appliances;

• • •

A fire involving energized electrical equipment is not classified by its electrical property.

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In the American standard, fires are classified as:
• •

Class A fire: Ordinary combustibles such as wood, paper, carton, textile, and PVC; Class B fire: Flammable liquid or gaseous fuels such benzene, gasoline, oil, butane, propane, and natural gas; Class C fire: Involving energized electrical equipment, often caused by short circuits or overheated electrical cables; Class D fire: Combustible metals, such as iron, aluminum, sodium, and magnesium; Class K fire: Containing a fat element, such as cooking oil



• •

Explosion
An explosion is a rapid increase in volume and release of energy in an extreme manner, usually with the generation of high temperatures and the release of gases. An explosion creates a shock wave. If the shock wave is a supersonic detonation, then the source of the blast is called a "high explosive". Subsonic shock waves are created by low explosives through the slower burning process known as deflagration.

Chemical
The most common artificial explosives are chemical explosives, usually involving a rapid and violent oxidation reaction that produces large amounts of hot gas. Gunpowder was the first explosive to be discovered and put to use. Other notable early developments in chemical explosive technology were Frederick Augustus Abel's development of nitrocellulose in 1865 and Alfred Nobel's invention of dynamite in 1866

Vapour
Boiling liquid expanding vapour explosions are a type of explosion that can occur when a vessel containing a pressurized liquid is ruptured, causing a rapid increase in volume as the liquid evaporates.

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Properties of explosions
Force
Explosive force is released in a vertical direction to the surface of the explosive. If the surface is cut or shaped, the explosive forces can be focused to produce a greater local effect; this is known as a shaped charge.

Velocity
The speed of the reaction is what distinguishes the explosive reaction from an ordinary combustion reaction. Unless the reaction occurs rapidly, the thermally expanded gases will be dissipated in the medium, and there will be no explosion. Again, consider a wood or coal fire. As the fire burns, there is the evolution of heat and the formation of gases, but neither is liberated rapidly enough to cause an explosion. This can be likened to the difference between the energy discharge of a battery, which is slow, and that of a flash capacitor like that in a camera flash, which releases its energy all at once.

Evolution of heat
The generation of heat in large quantities accompanies most explosive chemical reaction. The exceptions are called entropic explosives and include organic peroxides such as acetone peroxide[2] It is the rapid liberation of heat that causes the gaseous products of most explosive reactions to expand and generate high pressures. This rapid generation of high pressures of the released gas constitutes the explosion. The liberation of heat with insufficient rapidity will not cause an explosion. For example, although a pound of coal yields five times as much heat as a pound of nitroglycerin, the coal cannot be used as an explosive because the rate at which it yields this heat is quite slow. When a chemical compound is formed from its constituents, heat may either be absorbed or released. The quantity of heat absorbed or given off during transformation is called the heat of formation. Heats of formations for solids and gases found in explosive reactions have been determined for a temperature of 15 °C and atmospheric pressure, and are normally given in

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units of kilocalories per gram-molecule. A negative value indicates that heat is absorbed during the formation of the compound from its elements; such a reaction is called an endothermic reaction. In explosive technology only materials that are exothermic—that have a net liberation of heat—are of interest. Reaction heat is measured under conditions either of constant pressure or constant volume. It is this heat of reaction that may be properly expressed as the "heat of explosion."

Initiation of reaction
A chemical explosive is a compound or mixture which, upon the application of heat or shock, decomposes or rearranges with extreme rapidity, yielding much gas and heat. Many substances not ordinarily classed as explosives may do one, or even two, of these things. A reaction must be capable of being initiated by the application of shock, heat, or a catalyst (in the case of some explosive chemical reactions) to a small portion of the mass of the explosive material. A material in which the first three factors exist cannot be accepted as an explosive unless the reaction can be made to occur when needed.

Fragmentation
Fragmentation is the accumulation and projection of particles as the result of a high explosives detonation. Fragments could be part of a structure such as a magazine. High velocity, low angle fragments can travel hundreds or thousands of feet with enough energy to initiate other surrounding high explosive items, injure or kill personnel and damage property.

Reaction mechanism
In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical change occurs. Although only the net chemical change is directly observable for most chemical reactions, experiments can often be designed that suggest the possible sequence of steps in a reaction mechanism. Today, Electrospray Ionization Mass Spectrometry has been used to corroborate the mechanism of several organic reaction proposals. 44

A mechanism describes in detail exactly what takes place at each stage of a chemical transformation. It also describes each transition state, which bonds are broken (and in what order), which bonds are formed (and in what order) and what the relative rates of the steps are. A complete mechanism must also account for all reactants used, the function of a catalyst, stereochemistry, all products formed and the amount of each. A reaction mechanism must also account for the order in which molecules react. Often what appears to be a single step conversion is in fact a multistep reaction.

Type of reaction
There are different reasons and conditions that make a material explosive. Explosive material is often classified by the type of reaction that takes place.

Chemical
An explosion is a type of spontaneous chemical reaction (once initiated) that is driven by both a large negative enthalpy change (great release of heat) and a large positive entropy change (great quantities of gases are released) in going from reactants to products, thereby constituting a very thermodynamically favorable process in addition to one that propagates very rapidly. Thus, explosives are substances that contain a large amount of energy stored in chemical bonds. The energetic stability of the gaseous products and, hence, their generation comes from the formation of strongly bonded species like carbon monoxide, carbon dioxide, and (di)nitrogen, which contain strong double and triple bonds having bond strengths of nearly 1,000 kJ/mole. Consequently, most commercial explosives are organic compounds containing -NO2, -ONO2 and -NHNO2 groups that when detonated release gases like the aforementioned ones (e.g., nitroglycerin, TNT, HMX, PETN, nitrocellulose).[1] Explosives are classified as low or high explosives according to their rates of burn: low explosives burn rapidly (or deflagrate), while high explosives detonate. While these definitions are distinct, the problem of precisely measuring rapid decomposition makes practical classification of explosives difficult.

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Decomposition
The chemical decomposition of an explosive may take years, days, hours, or a fraction of a second. The slower processes of decomposition take place in storage and are of interest only from a stability standpoint. Of more interest are the two rapid forms of decomposition, deflagration and detonation.

Toxic gases:
Toxic gases can be present in a the work place environment because the type of manufacturing process uses toxic substances as part of the production process, or biological and chemical "breakdown" of the product being stored in a tank, and from maintenance activities (welding) being performed in the confined space. Common types of toxic gases encountered in chemical companies are are:


Hydrogen Sulfide - "sewer gas" a colorless gas with the odor of rotten eggs. Excessive exposure has been linked to many confined space deaths. Hydrogen sulfide causes a loss of our sense of smell, causing people to mistakenly think that the gas has left the space. Hydrogen sulfide inhibits the exchange of oxygen on the cellular level and causes asphyxiation. Carbon monoxide - is an odorless, colorless gas that is formed by burning carbon based fuels (gas, wood). Carbon monoxide inhibits the body’s ability to transport oxygen to all parts of the body. Solvents and chemical vapors - many solvents and other chemicals, such as Ammonia, Chlorine, Phosgene, Para nitro etc. are not only flammable, but if inhaled at high concentrations can cause central nervous system (CNS) effects. CNS effect can include dizziness, drowsiness, lack of concentration, confusion, headaches, coma and death.





Health Hazards

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Although safety hazards related to the physical characteristics of a chemical can be objectively defined in terms of testing requirements (e.g. flammability), health hazard definitions are less precise and more subjective. Health hazards may cause measurable changes in the body - such as decreased pulmonary function. These changes are generally indicated by the occurrence of signs and symptoms in the exposed employees - such as shortness of breath, a non-measurable, subjective feeling. Employees exposed to such hazards must be apprised of both the change in body function and the signs and symptoms that may occur to signal that change. The determination of occupational health hazards is complicated by the fact that many of the effects or signs and symptoms occur commonly in non-occupationally exposed populations, so that effects of exposure are difficult to separate from normally occurring illnesses. Occasionally, a substance causes an effect that is rarely seen in the population at large, such as angiosarcomas caused by vinyl chloride exposure, thus making it easier to ascertain that the occupational exposure was the primary causative factor. More often, however, the effects are common, such as lung cancer. The situation is further complicated by the fact that most chemicals have not been adequately tested to determine their health hazard potential, and data do not exist to substantiate these effects. There have been many attempts to categorize effects and to define them in various ways. Generally, the terms "acute" and "chronic" are used to delineate between effects on the basis of severity or duration. "Acute" effects usually occur rapidly as a result of short-term exposures, and are of short duration. "Chronic" effects generally occur as a result of longterm exposure, and are of long duration. The acute effects referred to most frequently are those defined by the American National Standards Institute (ANSI) standard for Precautionary Labeling of Hazardous Industrial Chemicals (Z129.1-1988) - irritation, corrosivity, sensitization and lethal dose. Although these are important health effects, they do not adequately cover the considerable range of acute effects which may occur as a result of occupational exposure, such as, for example, narcosis.

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Similarly, the term chronic effect is often used to cover only carcinogenicity, teratogenicity, and mutagenicity. These effects are obviously a concern in the workplace, but again, do not adequately cover the area of chronic effects, excluding, for example, blood dyscrasias (such as anemia), chronic bronchitis and liver atrophy. The goal of defining precisely, in measurable terms, every possible health effect that may occur in the workplace as a result of chemical exposures cannot realistically be accomplished. This does not negate the need for employees to be informed of such effects and protected from them. Appendix B, which is also mandatory, outlines the principles and procedures of hazard assessment. For purposes of this section, any chemicals which meet any of the following definitions, as determined by the criteria set forth in Appendix B are health hazards. However, this is not intended to be an exclusive categorization scheme. If there are available scientific data that involve other animal species or test methods, they must also be evaluated to determine the applicability of the HCS. 1. "Carcinogen:" A chemical is considered to be a carcinogen if: (a) It has been evaluated by the International Agency for Research on Cancer (IARC), and found to be a carcinogen or potential carcinogen; or (b) It is listed as a carcinogen or potential carcinogen in the Annual Report on Carcinogens published by the National Toxicology Program (NTP) (latest edition); or, (c) It is regulated by OSHA as a carcinogen. 2. "Corrosive:" A chemical that causes visible destruction of, or irreversible alterations in, living tissue by chemical action at the site of contact. For example, a chemical is considered to be corrosive if, when tested on the intact skin of albino rabbits by the method described by the U.S. Department of Transportation in appendix A to 49 CFR part 173, it destroys or changes irreversibly the structure of the tissue at the site of contact following an exposure period of four hours. This term shall not refer to action on inanimate surfaces.

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3. "Highly toxic:" A chemical falling within any of the following categories: (a) A chemical that has a median lethal dose (LD(50)) of 50 milligrams or less per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each. (b) A chemical that has a median lethal dose (LD(50)) of 200 milligrams or less per kilogram of body weight when administered by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between two and three kilograms each. (c) A chemical that has a median lethal concentration (LC(50)) in air of 200 parts per million by volume or less of gas or vapor, or 2 milligrams per liter or less of mist, fume, or dust, when administered by continuous inhalation for one hour (or less if death occurs within one hour) to albino rats weighing between 200 and 300 grams each. 4. "Irritant:" A chemical, which is not corrosive, but which causes a reversible inflammatory effect on living tissue by chemical action at the site of contact. A chemical is a skin irritant if, when tested on the intact skin of albino rabbits by the methods of 16 CFR 1500.41 for four hours exposure or by other appropriate techniques, it results in an empirical score of five or more. A chemical is an eye irritant if so determined under the procedure listed in 16 CFR 1500.42 or other appropriate techniques. 5. "Sensitizer:" A chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical. 6. "Toxic." A chemical falling within any of the following categories: (a) A chemical that has a median lethal dose (LD(50)) of more than 50 milligrams per kilogram but not more than 500 milligrams per kilogram of body weight when administered orally to albino rats weighing between 200 and 300 grams each.
(b)

A chemical that has a median lethal dose (LD(50)) of more than 200 milligrams per

kilogram but not more than 1,000 milligrams per kilogram of body weight when administered 49

by continuous contact for 24 hours (or less if death occurs within 24 hours) with the bare skin of albino rabbits weighing between two and three kilograms each. (c) A chemical that has a median lethal concentration (LC(50)) in air of more than 200 parts per million but not more than 2,000 parts per million by volume of gas or vapor, or more than two milligrams per liter but not more than 20 milligrams per liter of mist, fume, or dust, when administered by continuous inhalation for one hour (or less if death occurs within one hour) to albino rats weighing between 200 and 300 grams each. 7. "Target organ effects." The following is a target organ categorization of effects which may occur, including examples of signs and symptoms and chemicals which have been found to cause such effects. These examples are presented to illustrate the range and diversity of effects and hazards found in the workplace, and the broad scope employers must consider in this area, but are not intended to be all-inclusive.
a.

Hepatotoxins: Chemicals which produce liver damage Signs & Symptoms: Jaundice; liver enlargement Chemicals: Carbon tetrachloride; nitrosamines Nephrotoxins: Chemicals which produce kidney damage Signs & Symptoms: Edema; proteinuria Chemicals: Halogenated hydrocarbons; uranium c. Neurotoxins: Chemicals which produce their primary toxic effects on thenervous system Signs & Symptoms: Narcosis; behavioral changes; decrease in motor functions Chemicals: Mercury; carbon disulfide d. Agents which act on the blood or hemato-poietic system: Decrease hemoglobin function; deprive the body tissues of oxygen Signs & Symptoms: Cyanosis; loss of consciousness Chemicals: Carbon monoxide; cyanides

b.

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e.

Agents which damage the lung: Chemicals which irritate or damage pulmonary tissue Signs & Symptoms: Cough; tightness in chest; shortness of breath Chemicals: Silica; asbestos

f.

Reproductive toxins: Chemicals which affect the reproductive capabilities including chromosomal damage (mutations) and effects on fetuses (teratogenesis) Signs & Symptoms: Birth defects; sterility Chemicals: Lead; DBCP

g.

Cutaneous hazards: Chemicals which affect the dermal layer of the body Signs & Symptoms: Defatting of the skin; rashes; irritation Chemicals: Ketones; chlorinated compounds

h.

Eye hazards: Chemicals which affect the eye or visual capacity Signs & Symptoms: Conjunctivitis; corneal damage Chemicals: Organic solvents; acids

Operational Safety
OPERATIONAL & MAINTENANCE SAFETY Operational Safety/ mechanical Guards PRINCIPLES Preventive safeguards against injuries from moving machineries/objects. The basic step to prevent accident: a. Minimize the hazard from the machine, method, material, structure etc.by providing mechanical guards b. Control the hazard by enclosing or guarding it at its source. c. Train personnel to identify that hazard and to follow the safe working method of protection d. Use personal protective equipment necessary.

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e. Minimize process hazards by providing instrumentation for safe operation and shutdown/start up Need and Importance of Machine Guarding Basic need of machine guarding is to protect against injuries due to moving machinery and failure due to mechanical, electrical, chemical or human cause. The presence of guards provides personal protection and safe environment for normal operations. Safe Operation through Instrumentation. Use of instrumentation system for the safe operation is a very common practice and it can be achieved by using equipment for maintaining and control of key process parameters, process-interlocking system, on line analyzers etc. Safeguard through instrumentation can be categorized as:

Process Control In a process, the major controls are based on flow, temperature and pressure. Along with failure of services. Any increase or decrease in concentration of any component May not permissible or control of process parameters within set limit. To avoid unsafe condition, Continuous monitoring of parameters are necessary and suitable interlocks are provided Plant process interlocks are generally designed for cutting off the source of energy when the controlled process crosses the specified limit. Safe process conditions are established. Control valve action on supply failure is selected in such a way that they are based on philosophy of fail-safe operation. Equipment Safeguard

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Where moving machinery like compressors is of prime importance and these equipments are in operation continuously, then parameters, which can generate unsafe condition for these equipments, -e.g. high pressure, and lubrication failure, cooling water failure are sensed continuously. In case it crosses specified limit, signal for stopping moving machine in generated through interlock system. Mechanical System Safe Guards Pressure Relieving Devices The possibilities for development of excess pressure exist in nearly every process plants. It is important to understand how the excess pressure can occur and what might be eventual result. Excess pressure can lead to explosion. During chemical reaction, change in reaction composition, change in process parameter, In reciprocating pumps or compressor and due to external fire around equipment, failure of protective devices, alarm trips, interlocks & an endless list of related and unrelated situation. These may result into undesirable events causing injury to person, loss of equipment and / or human life & breakdown. To prevent any failure in the pressurized system, reaction vessel, or storage tank, it is very essential to install pressure-relieving devices. Pressure Relief Valve is the general term applied to the various types of valves, which are used to relieve pressure. The term "Safety Valve", "Relief Valve" is also used some time with the pressures, definition but often more loosely type of pressure relieving devices are

Relief Valve
A relief valve is an automatic pressure relieving device actuated by static pressure up stream of the valve, and which opens further with increase in pressure over the

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operating pressure; that means, it opens gradually in proportion to the excess of pressure over the opening pressure. It is primarily used for liquid services.

Safety Valve
A safety valve is an automatic valve pressure relieving device actuated by the static pressure-up-stream of the valve and characterized by full opening or "POP" action upon opening. It is normally installed at the vapor phase of vessel. It used for steam, gas or vapor services. Rupture Disk: It is a thin diaphragm (may be from metal, plastic, non-metallic) held between two flanges and it is designed to burst at predetermined pressure. Rupture discs are installed invariably before the relief valve with pressure sensing device. Any increase in pressure will actuate necessary corrective action before major discharge to atmosphere via relief valve system. It is used for low as well as high-pressure protection of vessels and pipelines where sudden and total release of over pressure can be controlled. When the disc has ruptured, the process material and system is exposed to the environment or backpressure of the discharging system, whether atmospheric or other vent system. After each bursting it is required to be replaced. Generally it is used in corrosive services, toxic or "leak-proof" application. It is also installed where bursting pressure is not easily accommodated by the conventional or explosion. Depending upon the requirement of pressure and process material, a different type of rupture discs are available and is being used. It is applicable to steam, gas vapor liquid & slurry. Rupture disc line is connected with "blow down tank". It is required for environment protection. Check Point:

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I.

Tag on each rupture disc indicating its identification No, Location, Capacity i.e. range, the land of utility etc.

II.

Checking the condition of disc & inspection of disc at least once in a year.

Machine Guards: Machine guarding is too frequently misunderstood that it is only concerned with the point of operation or with the means of power transmission but machine guarding is also necessary to prevent injury from other causes while working on or around moving machine. In continuous process, it is very essential to ensure continuous production stream, employee’s safety and health and reduce equipment damage, which emphasizes the need to identify and remove all possible hazards associated with the job by engineering practices. Positive prevention of injury producing accidents on moving machinery can be ensured through the installation of safeguards or through engineering revision or deducing of the equipment, having moving parts which are operated without guards or with incomplete or ineffective guards. Specifically machine guarding protects against and prevents injuries from these sources: a. Direct contact with the moving parts of a machine. b. Work in process (kick backs on a circular ripsaw, metal chips, from a machine tool or from abrasive grinding wheel). c. Machine failure, which usually results from lack of preventive maintenance. Overloading metal fatigue or abuse. d. Electrical failure, which may cause malfunctioning of machine, or cause electrical chocks or busses. e. Individual failure, resulting from such thing as curiosity, zeal, distraction, fatigues, indolence, worry, anger, and illness and deliberate chance taking.

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Statutory Requirements
Guards to be provided on the rotating machinery as per section 21 of the Factory Act. a. Every moving parts of a prime mover and every flywheel connected to prime mover. b. The headrace and tailrace of every water wheel in engine turbine. c. Any parts of stock but which is projected beyond the headstock of lathe. d. Unless they are in such position or of construction as to be safe to every person employed in the factory as they be if they were securely fenced, the following namely. i. ii. iii. Every part of an electric generator, a motor or rotary converter. Every part of transmission machinery. Every dangerous part of any other machinery.

Shall be securely fenced by safe guards of substantial construction which shall constantly be maintained and kept in position and the part of machinery in motion, Safety Precaution: a. While installing machine & its guard ensure that there is sufficient space available for maintenance & repair and for incoming & outgoing movement of man and materials. b. c. d. e. f. Confirm all specification as per IS for guarding. Guard should not weaken the structure of machine. Guard should be considered as permanent part of machine. Guard should be durable, resistant to fire and corrosion and easily repaired. It should be convenient; it must not interfere with the efficient operation of machine nor cause discomfort / obstruction to operator.

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g. h.

Guard should be constructed strong enough to resist normal wear, shock and vibrations and to withstand long use with minimum maintenance. Guard itself should not pose hazards such as splinters, pinch points, shear points rough / sharp edges and corners and may create other sources of injury.

i.

When the guard is prepared for specification and specific machine, provision for lubrication, oiling, repairing, inspection and adjustment of machine parts should be considered, while designing.

j.

Whenever guards or safety devices are removed to carry out repair, adjustment or maintenance, the power for the machinery should be isolated with switches locked & tagged.

k.

Guard should be such that it prevents access to the danger zone or point of operation.

Operator
a. b. c. Operator should never attempt to carry out work on moving machinery. Operator should not start any machine unless the guard is in its position and in good condition. Person working wearing neckties, mufflers, loose clothing, wrist watches, rings or other jewelry etc. should not be permitted to work on or near moving machinery. d. e. f. Before removing any guards from machinery ensure that power supply to the machinery is isolated locked & tagged. Whenever any equipment or machinery is to be handed over after maintenance, the guard shall be fixed in its position. Operator should inform the concerned superior regarding any damage or missing guards. Then engineer has to arrange for repair / replacement.

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Type of Guard Fixed Guard: The fixed guard is one of the best guard or barrier provided by manufacturer in machine. This guard is usually designed and considered as an integral part of the machine and therefore superior to those made on site in appearance, convenience or arrangement and then functional value. It provides one of the most effective ways to keep away danger area from the operator. A fixed guard gives highest degree of protection and should be used where possible when access to the danger part or area is not required during normal operation of machinery. Some times fixed guards may be of adjustable type to accommodate different sets of tools, for adjustment, oiling, lubrication or inspection but once this adjustment is carried out then there should not be any movement or detachment of it and in no way it should reduce effectiveness of the guard, its working or protection. Interlocking Guard: If the fixed guard is imperceptible to use when it is required to access danger area during normal operation. The first choice is to use interlocking guard. This interlocking guard may be mechanical, electrical, pneumatic or combination of any above. All the parts of the interlocking system should be considered at the design stage of the machine. The interlocking guard prevents the operation of control so that when guard is in its position allows machine in motion and thus operator cannot reach to the points of operation or point of danger. When guard is open, it permits access to dangerous parts, the starting mechanism is locked and a locking pin or safety device prevents the operation of main mechanism. The guard should not be opened when the machine is in motion. It can be opened only when machine has come to rest or has reached to a fixed position in its travel.

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Trip Guard: In a continuous motion machine, generally where hands, other body parts or an operator can temporarily reach in the space swept by dangerous parts or where entanglement in an article or material being fed, trip guards can effectively be used. The guard should be so arranged that an approach by a person beyond safe limits cause the guard to actuate the tripping mechanism to stop machinery or reverse its motion. The tripping device may be a mechanical or photo electric trip device. In a photoelectric device, a light beam is arranged as a detecting curtain of path between operator and dangerous parts of machine. The controls may be mechanical or electrical, and locked in such a way that it cannot be operated by one hand and other body parts. It needs simultaneous operation of either two push buttons or pneumatic valves or mechanical levers etc. to run the system / mechanism. If more than one operator is required to work on machine, then two-hand control device should be provided for each operator and unless all operators operate their device together, the machine should not start. By keeping control knobs / levers away from danger area two hand control method protect any body part to in contact with danger area. In the event of interruption of the curtain, machine cannot be set in motion and if dangerous part is in motion. The device should arrest or reverse the motion of the dangerous parts. Interlocks and tripping guards provided at nitro aromatic plants, nitrite section for process safety. All interlocks and tripping loops are checked regularly by production and instrument dept. and maintained records of it.

Flame Arrester

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Flame arrester or flame trap is a device used to prevent the passage of a flame or explosion. Propagation along with the duct, vent lines or pipes. The flame arrester is normally installed between vent vapor space of storage tank containing flammable liquids on the pipe line supplying fuel gas to the burner on certain pipelines conveying flammable gases within the plant on flare states and on the vent of various process vessels. Flame arresters are also used to prevent flame pushing back through a vent to ignite a flammable mixture in up stream of flame arrester i.e. vapor space of storage tank or duct / pipeline / floor stack / engine. Mostly the construction of flame arrester is an assembly of narrow passage through which only gases or vapors can flow. The passages are too narrow to allow the flame to pass through. When the flame arrester is installed in upstream of burner of boiler or flare stack where only hot gas may be forced through or and flame may stabilize on or near the flame arrester then it has not only to prevent the simple flash back but it has to dissipate / absorb considerable amount of heat and has ability to withstand mechanical shock including explosion. In general, flame arresters are cheap, can be easily installed and are readily replaced if damaged due to their fine structure they create / ruse some their fine problems. These included high-pressure drop and blockages. A high free cross sectional area should be available for gas flow and low resistance to flow and freedom from blockage, a high capacity for absorbing heat of flame and ability to withstand mechanical shock including explosion. The varieties of flame arresters are available and they vary in their design and material of construction. Depending upon the process requirement and reaction, different type of flame arresters are used namely crimped metal arrester perforated plate arrester, wire gauge arrester, parallel plate arrester, sintered arrester, wire pack arrester packed bed arrester hydraulic arrester etc. The design of flame arrester depends on combustion properties of the flammable mixture and on the function and location of arrester in the system.

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The maintenance of flame arrester in working condition and regular inspection and cleaning is necessary to prevent vacuum formation in a tank or over pressurization in a tank due to chocking of flame arrester. This may lead to bursting of tank / equipment due to over pressurization or buckling due to vacuum in extreme conditions. Chemical process requirements necessitate the use of various types of gas cylinders for different activities. As these gases are pressurized liquefied / compressed and stored in cylinders there is need for identification of gases by definite color code applied on exterior of cylinder it is very essential that safety in handling of these cylinders must be properly ensured as some of these gases are injurious to the human system. The hazards arising out of misuse of the cylinders are a matter of great concern. Accidents due to bursting of cylinders are not uncommon and when they occur are dangerous life and limb and danger to property can be very serious indeed.

Identification of industrial cylinders:
Gas cylinders are painted in different colors according to the contained gases so that their visual identification is easy. These colors however get abraded, obliterated or blurred by rough handling and frequent use. They often need a good face-lift; extra care is necessary in identifying the contents of such cylinders. Chlorine, Sulfur dioxide, Ethyl chloride storage and handled in cylinders and Ammonia storage and handle in bullets. Laboratory gas cylinders like hydrogen, Nitrogen and air also storage and handled at site. Freon used for chilling unit of utility. Acetylene and air cylinder also used for fabrication activities at site. Name of Gas Cl2 Ethyl Chloride SO2 Ground Colors Golden Yellow Black Gray Light Brunswick Green Colors band None None Golden Yellow 61

Acetylene Freon H2 CO2 LPG Oxygen Nitrogen

Maroon None Dual Colored Bottom End -Gray Neck End Violet Signal Red Signal Red Signal Red Gray Dual Colored Bottom End Gray Neck End Black -Golden Yellow ----

Handling and use of cylinders:
a) Use EOT crane for Cl2 , So2& ETH gas cylinders. b) Ensure working condition of scrubbing system and availability of elephant hose connection nearest to handling area. c) All attachment of tubes and gaskets must be inspected strength before connection d) Leak test must be carried out while startup transferring. e) Necessary PPE's must be observed while handling of Cl2, So2 & ETCL gas cylinders. f) Keep ready of emergency kit, respiratory appliances and necessary PPE's. g) Regulation demands that oxygen and acetylene must be stored separately in wellventilated safe place preferably at ground level away from excessive heat and physical hazards. h) For Ammonia unloading and handling ensure care fully strength of transferring SS hose and gasket while connection with tanker to tank. i) Ensure pressure and level and of tank before unloading. j) When stored inside a building, cylinders of oxygen should be not in close proximity to gases. k) Cylinders must be kept away from sources of naked spark or heat or potential sources of heat. Do not store in direct sunlight. l) Never attempt to transfer different gases from one cylinder to another or to mix in a cylinder. m) Grease and oil must be kept away from oxygen cylinders since oxygen under pressure can cause spontaneous combustion when in contact with them. 62

n) When in use or in storage, cylinders must either be secured on a cylinder cart or chained to a firm support so they will not topple over. o) When moving cylinders, the valve cap must be in place. Never hoist a cylinder by its protective cap. p) Never drop cylinders on the ground, they could burst or valves might be broken or seriously damaged. q) Never drag or slide cylinders across the ground as that can result in damage. r) Cylinder must never be used as rollers or supports for anything. s) Never strike an electric are on a cylinder. t) Never place cylinders where they could become part of an electrical circuit and through accidental arcing cause a fire. u) Empty cylinder should have the valve closed, protective cap replaced and be marked empty or 'MT'. Return them promptly to the supplier. v) Leaking cylinder must be taken outdoor at safe place and clearly tagged if the leak cannot be stopped by fighting the valve packing nut; return the cylinder to supplier when completely empty. It is illegal to ship leaking cylinder because of the hazardous involved. w) Acetylene cylinders shall always be stored or used in an upright position. If this is not done acetylene may flow through resulting in faulty operation. x) Gas cylinder must not be taken into tanks or confined spaces. y) Low-pressure regulators, hoses, couplings etc. must never be used for any gas that is under high pressure. z) Before connecting regulators to cylinders clean the cylinder valve very carefully to clear out any foreign matter that might harm seats, clog orifice or cause ignition. Always stand to one side of the out let when opening the valves to pressure up regulators or lines. aa) Ensure Emergency kit placed in working area and scrubbing system worked properly. Note: Do not break the valve of cylinders for this purpose, as it could be dangerous. 1) 2) Use correct size wrenches when tightening regulator nut on to cylinder valve. Always open the valve on the cylinder slightly so that the high-pressure gauge.

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If a regulator gauge, indicating a malfunction on the part of the regulator. In such cases close the cylinder valve, remove the regulator and have it

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FIRE CHEMISTRY 1.1 Fire Phenomenon. For a fire to start, four elements are essential. 1. Fuel (Combustible material and reducing agent). 2. Oxygen or Oxidant or Oxidizer (From the atmosphere). 3. Heat or source of ignition. (Necessary) to start the fire initially, but maintained by the fire itself once it has started). 4. Maintenance of chain reaction through free radicals. These four sides constitute a “Fire Pyramid." (Instead) of the old concept of fire triangle). If any one of above four elements is removed, the fire goes out. There fore methods of fire extinguishments. They are dependent on: 1. Removing or shutting of the source of fuel. 2. Excluding oxygen or decreasing it bellow 14% to 18% by adding inert gases. 3. Removing heat from the fire. 4. Removing free radicals to discontinue chain reaction and flame propagation. 5. Dry powder chemicals and halogenated hydrocarbons capture free radicals and Put off fire in this way. Thus fire is rapid chemical oxidation-reduction reaction. It is an oxidation of substance accompanied by heat, light and flame. Due to incomplete combustion it evolves smoke and carbon monoxide that create invisibility and toxic atmosphere for fire fighters. An excess of air can cool the combustion gases to quench the fire, if the combustible material is small; otherwise it can't as in case of forest fire where the combustible material is too much to cool. The chemicals reaction is exothermic as it evolves heat and the heat released is used for the reaction to continue. Fire is a burning or combustion phenomena and the combustion may be kinetic or diffusive depending upon

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homogeneous or inhomogeneous air-fuel-air mixture. The combustion may be complete or incomplete. The complete combustion gives product like CO2, SO2, Water, and Vapour etc., which can't burn any more. The incomplete combustion (due to insufficient air) gives CO, alcohols, aldehydes etc. This can continue to burn. The amount of air required to burn 1kg. Of material. (Or 1m3 of gas is roughly given by V=1/2 Q/100 where Q is the heat (calorific value) of combustion. KJ/ kg or KJ/ m3. Rate of burning also depends on the status of fuel i.e. solid, liquid or gas. 2.0 CLASSIFICATION OF THE FIRE AND SELECTION OF THE FIRE EXTINGUISHERS. Following table given the class of fire (A to D) and portable fire extinguishers better effective to extinguisher for them. CLASS OF FIRE A Fire involving ordinary Combustible • material like wood, paper, textile etc. where the cooling effect of water is essential for the extinction of fires. B. • • DESCRIPTION EXTINGUISHING MEDIA Water Soda acid, type Water type (Gas pressure) Water type (Constant air pressure) Foam Carbon dioxide Dry powder Carbon dioxide IS CODE 934 940 6234 933 2878 2171 4308 2878

Fire in flammable liquids like oils, • solvents, petroleum, varnishes, paints • etc. where a something effect is • essential.

C.



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Fire involving gaseous substances • under pressure where it is necessary to dilute the burning gas at a very fast • with an inert gas or powder. Fire involving electrical equipment where the electrical non- conductivity of the extinguishing media is of D. primary importance. Fire involving metals like Mg, Al, Zn, • K etc. where the burning metals are reactive to water and which requires special extinguishing media or technique. Source of Ignition Electrical Equipment Fires

Dry Powder CO2

2171 4308 2878

Special Dry Powder

-

Overheating of electrical wiring resulting from short circuits of improperly installed or maintained electrical equipment are two leading causes of fires.  Only approved type of electrical equipment should be used.  Temporary or make shift wiring, particularly if defective or overloaded is an outstanding cause of fire. It should not be used in damp places and explosion proof lamps and fixtures should be used in explosion hazard areas.  Portable electrical tools and extension cords should be inspected frequently and repaired promptly, water proof cords and sockets should be used in damp places and explosion proof lamps and fixtures should used in explosion hazard areas.  All electrical equipment, particularly portable electric tools should be grounded or double insulated for the protection of persons using it.

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 Lamp bulbs should protect by heavy lamp guard or by adequately sealed transparent enclosures and kept away from sharp objects and from falling. Bare bulb should never be used when exposed to flammable dust or vapors.  Employees should be instructed in the use of electrical equipment and should be prohibited from tampering, blocking circuit’s breakers, using wrong fuses, bypassing fuses and installing equipment without authorisation.  Electrical installation and equipment should be periodically inspected and tested to ensure continued satisfactory performance and to detect deficiencies. Smoking Carelessly discarded cigarette butts and bidis are a major source of fire. Smoking should be permitted at specific safe places. “No Smoking “areas should be marked with conspicuous signs should be rigidly enforced. Everyone should adhere to instructions with regard to ban on carrying of smoking materials of any kind into hazardous areas. Friction Excessive heat generated by friction causes a very high percentage of industrial fires. A program of preventive maintenance on plant machinery can avert fires resulting from inadequate lubrication, misaligned bearing, choking or jamming of materials, poor adjustment of power drives and conveyor, broken or bent equipment. Fire frequently results form overheated transmission bearings and shafting in buildings where dust accumulates such as grain elevators, cereal, textile, wood working plants. Frequent inspection and oiling of bearing should be done. Accumulation of dust should be cleaned frequently to prevent oil from dripping to the floor or on combustible below. Foreign objects Every precaution should be taken which might strike sparks from entering machines or process where there are flammable dusts, vapors or combustible material such as

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cotton limit or metal powder. Screens or magnetic separators are commonly used for this purpose as in textiles, grains elevators and other operations that have explosive mixture or dusts. Open flames Although open flames are probably the most obvious source of ignition for ordinary combustible and one would think they could be most easily avoided, they still account for a large percentage of industrial fires. Heating, equipment, torches and welding cutting operations are principal offenders. A. Air heaters (Gas or Oil fired)

Air heaters cause fires because of  Overheating of the air heater igniting nearby combustible material.  Failure to insulate air heaters other combustible bases.  Failure to provide substantial protective shield. From sparks  Failure to secure base with proper anchoring. B. Torches

When acetylene or LPG torches are used they should be placed to safely secure in a gas cylinder trolley. They should not be used around flammable liquids, papers or similar combustible material.

C.

Welding & Cutting

When possible, welding and cutting should be done in special fire safe area or rooms with concrete or metal plate floors. Flame impingement on concrete may cause damage to it. Consequently work should be kept off the floor or else a metal shield should protect the floor.

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In case where welding and cutting operations are performed outside the special fire safe areas, Hot Work Permit system should be adopted. When welding is done outside a shop or area designated for welding, observers should be stationed to prevent sparks or molten slag from starting fires or to extinguish fires. The observer should remain at the work location for at least one hour after the time of their inception. However, it will be better to pour a bucket of water after the hot job is over. Shield or fire resistant blankets should be installed around spot welding from reaching combustible material nearby or from injuring employees. Spontaneous Ignition Spontaneous ignition result due to oxidation of organic compounds. With generation of heat. Under certain conditions, this gets accelerated until the ignition temperature of fuel is reached. This condition is reached when there is sufficient air for oxidation but not enough ventilation to carry away the heat as fast as it is generated.

This is a condition usually found in quantities of bulk material packed loosely for a large amount of surface exposed for oxidation, yet without adequate air circulation to dissipate heat exposure to high temperature increases the tendency towards spontaneous ignition. The presence of moisture also can advance spontaneous heating unless the material is wet beyond a certain limit. It is generally agreed that at ordinary temperatures some combustible substances oxidize slowly and under certain conditions can each their ignition temperature. These include vegetable oils, animal oils and fats, coal, charcoal and finely divided metals like iron, nickel, aluminum and magnesium etc. Temperature of 1400 F ( 600 C) is considered dangerous for coal piles. If temperatures increase rapidly it is advisable to rearrange the pile for better circulation of air. The best prevention against spontaneous ignition is either total exclusion of air or good ventilation.

Housekeeping
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1.

Collection and storage of combustibles Many fires are the direct result of accumulation of oil soaked and paint saturated clothing, rages, wastes and combustible refuse. Such material should not be deposited in non-combustible refuse. Such material should be deposited in noncombustible receptacle having self-closing covers that are provided for this purpose and removed daily from the work area. Cotton, jute and other highly combustible fibrous material should be stored in covered and non- combustible containers and, if in large quantities on hand, in fire resistant rooms equipped with fire doors and automatic sprinklers. Accumulations of all types of dust should be cleaned at regular intervals from overhead pipes, beams and machines, particularly bearings and other hot surface. It must be understood that all organic as well as many inorganic materials if ground finely enough will burn and propagate flame. Roofs should be kept clean from sawdust, shavings and other combustible refuse. Such cleaning should be done preferably by vacuum cleaning. No such material should be stored or allowed to accumulate in air elevator, or stair, shafts tunnels in out of way corners, near electric motors or machinery, against steam pipes, within 10 feet of any stove, furnace or boiler.

2.

Rubbish disposal Burning rubbish in yard areas near combustible buildings, sheds, lumber, piles, fences and grass or other combustible materials often causes fires. If it must be burnt, the best and safest way is with a well-designed incinerator that meets the requirement of the environment pollution control laws.

3.

Lockers

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Lockers in which oil soaked clothing waste and newspapers are kept always pose a serious fire hazard. Lockers of metal and having fire resistant sides and backs with doors having ventilation provision should be provided.

Explosive Atmosphere
DUSTS A dust explosion hazard exists whenever material that will burn or oxidize readily is available in powder form because the surface (contact) area of each particle is very large in relation to its mass. There are two ways to prevent dusts explosions.

1.

Prevent the formation of explosive mixture of dust in air. Extra ordinary precautions should be taken to prevent the accumulation of dust; Extensive use of local exhaust and frequent cleaning will minimize the hazard. Whenever possible, dust operations should be segregated and dust producing equipment should be totally enclosed and exhausted to prevent leakage of dust in the general work area.

2.

Ignition of an explosive mixture of dust and air may be prevented by control of open flame, friction, sparks, static electricity, welding and excessive heat or by increased humidity or by using inert gas. Every precaution should be taken to prevent overheated bearing, smoking; frictional sparks from hand tools from grinding or welding operations and from static electricity. Only non-ferrous tools should used in dust exposures and employees must wear shoes with nonferrous nails. Only dust tight wiring fixtures and motors should be used.

Gases and Vapors

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Gases and vapors that produce flammable mixture with air or oxygen are common in industry, such gases are acetylene, propane, carbon monoxide, methane and natural gas etc. Highly flammable liquids that emit flammable vapor include RLNG, Benzene, Toluene, PNT, MNT, MCB, ONCB, Methanol, etc.

When flammable liquids including those with flash point above 1000 F must be handled and used only in minimum quantity and in safety containers. Other precautions is to use explosion proof electrical fittings, effective exhaust and ventilation system, safety permit system to carryout hot jobs in that area and frequent testing of atmosphere to check the generation and formation of explosive mixtures. Should be diligently followed. Static Electricity Sparks resulting from accumulation of static electricity are common causes of ignition for accidental fires and explosions. Static charge may develop from handling solids, liquids or gases or from the operation of equipment such as the belts. The flow of organic liquids over a speed of 0.7-m/ sec. generates static electricity. The in the presence of inflammable vapor, dusts and gases are hazardous and where this may occur, necessary bonding and grounding should be incorporated. Jumpers should be provided over the flanged joints of solvent storage and handling equipments and pipelines. The bonding systems should be maintained inspected and tested periodically to ensure continuity of the system. Portable Fire Extinguishers Various types of portable fire extinguishers like carbon dioxide, dry chemical powder and mechanical foam are provided at various places in the factory. The regular inspection maintenance carried out in house periodically once in month. And hydro tests are carried out by external agency periodically.

Mechanical Foam 73

Description They are available in two sizes. The 9 Liters extinguisher is portable one while the 45 liters extinguisher is mounted on trolley. Aqueous film formation foam (AFFF) or alcohol resistance or protein solution contended in Foam type extinguisher is best suited for hydrocarbons and solvent fires. It extinguishes the fire by blanketing effect, cooling effect being very little. These extinguishers should never be used on electric and metallic fires. Operation Remove safety pin. Push the plunger. Keep up right the extinguisher Keep foam discharge jet over the burning liquid Carbon Dioxide Description These are available in cylinders of 15, 20 & 50 pounds capacity provided with a release valve and discharge horn for directing the gas on the seat of fire. The carbon dioxide puts out the fire by smothering by displacement of oxygen due to difference of vapor density & also the high velocity at which it comes out and cooling effect due to rapid physical change. Operation 1. 2. Pull out the locking pin (safety pin) on the cylinder valve. Open the valve and direct the horn at the base of the fire.

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3.

Continue the operation even after putting out the fire as the gas (CO2) will cool the matter and avoid recurrence of fire on the dame matter.

Dry Chemical Powder (DCP) Description They are available in our plants in capacities of 20, 50,150 and 300 pounds. The dry chemical powder extinguisher consists of an internally or externally mounted cartridge of pressurized carbon dioxide or nitrogen gas, which when the top is punctured/ open, expels chemically processed sodium bicarbonate powder in the outer shell through the hose and nozzle. The inert gas and the chemical action of powder smother the fire. Operation 1. Carry the extinguisher to the scene of fire. 2. Keep extinguisher upright and remove plunger guard clip. 3. Strike the plunger hard. 4. Direct the discharge at the base of flame, control flow by squeeze grip provided at the discharge end of the hose. 5. Once used, Fire station should be notified for replacement/ maintenance. Fire hydrant system Firewater reservoir tank s provided and storage capacity is 1700KLs. At Nitro section and 450KL at Nitrite Section the fire pumps are provided. Power supply given through GEB & one diesel operated pump also provided so that not required separate connection from DG set. Main hydrant pump capacity is 273 M3 / hrs. At 7-8 kg/ cm2 at Nitro Section Diesel pump capacity is 216 M3 / hrs.

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Hydrant points and hose boxes are provided at various locations. Fixed foam pourer system provided to flammable material storage tanks. Inventory of AFFF kept at fire station for fire fighting. Inertisation also provided to benzene and toluene tank also all process having facility of inertisation with Nitrogen gas. Firemen team kept round the clock in the factory.

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Plant operation
Process control
In process control, information gathered automatically from various sensors or other devices in the plant is used to control various equipment for running the plant, thereby controlling operation of the plant. Instruments receiving such information signals and sending out control signals to perform this function automatically are process controllers. Previously, pneumatic controls were sometimes used. Electrical controls are now common. A plant often has a control room with displays of parameters such as key temperatures, pressures, fluid flow rates and levels, operating positions of key valves, pumps and other equipment, etc. In addition, operators in the control room can control various aspects of the plant operation, often including overriding automatic control. Process control with a computer represents more modern technology. Based on possible changing feedstock composition, changing products requirements or economics, or other changes in constraints, operating conditions may be reoptimized to maximize profit.

Workers
As in any industrial setting, there are a variety of workers working throughout a chemical plant facility, often organized into departments, sections, or other work groups. Such workers typically include engineers, plant operators, and maintenance technicians. Other personnel at the site could include chemists, management/administration and office workers. Types of engineers involved in operations or maintenance may include chemical process engineers, mechanical engineers for maintaining mechanical equipment, and electrical/computer engineers for electrical or computer equipment.

Transport

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Large quantities of fluid feedstock or product may enter or leave a plant by pipeline, railroad tank car, or tanker truck. For example, petroleum commonly comes to a refinery by pipeline. Pipelines can also carry petrochemical feedstock from a refinery to a nearby petrochemical plant. Natural gas is a product which comes all the way from a natural gas processing plant to final consumers by pipeline or tubing. Large quantities of liquid feedstock are typically pumped into process units. Smaller quantities of feedstock or product may be shipped to or from a plant in drums. Use of drums about 55 gallons in capacity is common for packaging industrial quantities of chemicals. Smaller batches of feedstock may be added from drums or other containers to process units by workers.

Maintenance
In addition to feeding and operating the plant, and packaging or preparing the product for shipping, plant workers are needed for taking samples for routine and troubleshooting analysis and for performing routine and non-routine maintenance. Routine maintenance can include periodic inspections and replacement of worn catalyst, analyzer reagents, various sensors, or mechanical parts. Non-routine maintenance can include investigating problems and then fixing them, such as leaks, failure to meet feed or product specifications, mechanical failures of valves, pumps, compressors, sensors, etc.

Statutory and regulatory compliance
When working with chemicals, safety is a concern. In the India, law requires that employers provide workers working with chemicals with access to a Material Safety Data Sheet (MSDS) for every kind of chemical they work with. An MSDS for a certain chemical is prepared and provided by the supplier to whoever buys the chemical. Other laws covering chemical safety, hazardous waste, and pollution must be observed. Hazmat (hazardous materials) teams are trained to deal with chemical leaks or spills. Process Hazard Analysis (PHA) is used to assess potential hazards in chemical plants. .

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Plant facilities
The actual production or process part of a plant may be indoors, outdoors, or a combination of the two. The actual production section of a facility usually has the appearance of a rather industrial environment. Hard hats and work shoes are commonly worn. Floors and stairs are often made of metal grating, and there is practically no decoration. There may also be pollution control or waste treatment facilities or equipment. Sometimes existing plants may be expanded or modified based on changing economics, feedstock, or product needs. As in other production facilities, there may be shipping and receiving, and storage facilities. In addition, there are usually certain other facilities, typically indoors, to support production at the site. Although some simple sample analysis may be able to be done by operations technicians in the plant area, a chemical plant typically has a laboratory where chemists analyze samples taken from the plant. Such analysis can include chemical analysis or determination of physical properties. Sample analysis can include routine quality control on feedstock coming into the plant, intermediate and final products to ensure quality specifications are met. Nonroutine samples may be taken and analyzed for investigating plant process problems also. A larger chemical company often has a research laboratory for developing and testing products and processes where there may be pilot plants, but such a laboratory may be located at a site separate from the production plants. A plant may also have a workshop or maintenance facility for repairs or keeping maintenance equipment. There is also typically some office space for engineers, management or administration, and perhaps for receiving visitors. The decorum there is commonly more typical of an office environment.

Corrosion and use of new materials
Corrosion in chemical process plants is a big issue that consumes billions of dollars yearly. Electrochemical corrosion of metals is pronounced in chemical process plants due to the

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presence of acid fumes and other electrolytic interactions. Recently, FRP (Fibre-reinforced plastic) is used as a material of construction. The British standard specification BS4994 is widely used for design and construction of the vessels, tanks, etc.

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Runaway reactions

Thermal runaway refers to a situation where an increase in temperature changes the conditions in a way that causes a further increase in temperature, leading (in the normal case of an exothermic reaction) to a destructive result In chemical engineering, thermal runaway is a process by which an exothermic reaction goes out of control, often resulting in an explosion. It is also known as a "runaway reaction" in organic chemistry. Thermal runaway occurs when the reaction rate increases due to an increase in temperature, causing a further increase in temperature and hence a further increase in the reaction rate. It has contributed to industrial chemical accidents, most notably the 1947 Texas City disaster from overheated ammonium nitrate in a ship's hold, and the disastrous release of a large volume of methyl isocyanate gas from a Union Carbide plant in Bhopal, India in 1984. Thermal runaway is also a concern in hydrocracking, an oil refinery process. Thermal runaway may result from exothermic side reaction(s) that begin at higher temperatures, following an initial accidental overheating of the reaction mixture. This scenario was behind the Seveso disaster, where thermal runaway heated a reaction to temperatures such that in addition to the intended 2,4,5-trichlorophenol, poisonous 2,3,7,8-tetrachlorodibenzo-p-dioxin was also produced, and was vented into the environment after the reactor's rupture disk burst.
[1]

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Thermal runaway is most often caused by failure of the reactor vessel's cooling system. Failure of the mixer can result in localized heating, which initiates thermal runaway. Similarly, in flow reactors, localized insufficient mixing causes hotspots to form, where thermal runaway conditions occur, which causes blowouts of reactor contents and catalysts. Incorrect component installation is also a common cause. Many chemical production facilities are designed with high-volume emergency venting to limit the extent of injury and property damage when such accidents occur. Some laboratory reactions must be run under extreme cooling, because they are prone to hazardous thermal runaway. For example, in Swern oxidation, the formation of the sulfonium chloride must be performed in a cooled system (–30 °C), because at room temperature the reaction undergoes thermal runaway explosively.

Exothermic reaction

An exothermic reaction is a chemical reaction that releases energy in the form of heat. It is the opposite of an endothermic reaction. Expressed in a chemical equation: reactants → products + energy

An exothermic reaction is a chemical reaction that is accompanied by the release of heat. In other words, the energy needed for the reaction to occur is less than the total energy released. As a result of this, the extra energy is released, usually in the form of heat. When using a calorimeter, the change in heat of the calorimeter is equal to the opposite of the change in heat of the system. This means that when the medium in which the reaction is taking place gains heat, the reaction is exothermic. The absolute amount of energy in a chemical system is extremely difficult to measure or calculate. The enthalpy change, ΔH, of a chemical reaction is much easier to measure and

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calculate. A bomb calorimeter is very suitable for measuring the energy change, ΔH, of a combustion reaction. For an exothermic reaction, this gives a negative value for ΔH, since a larger value (the energy released in the reaction) is subtracted from a smaller value (the energy used for the reaction). For example, when hydrogen burns: 2H2 + O2 → 2H2O ΔH = −483.6 kJ/mol of O2

Endothermic
In thermodynamics, the word endothermic ("within-heating") describes a process or reaction in which the system absorbs energy from the surroundings in the form of heat. Its etymology stems from the Greek prefix endo-, meaning “inside” and the Greek suffix –ther, meaning “heat”. The opposite of an endothermic process is an exothermic process, one that releases energy in the form of heat. The term endothermic was coined by Marcellin Berthelot (25 October 1827 – 18 March 1907). The concept is frequently applied in physical sciences to, for example, chemical reactions, where thermal energy (heat) is converted to chemical bond energy. Endothermic, also known as endergonic, refers to a chemical reaction in which a system receives heat from the surroundings. Q>0 When this occurs at constant pressure: ∆H > 0 and constant volume: ∆U > 0

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If the surroundings do not supply heat (e.g., when the system is adiabatic), an endothermic transformation leads to a decrease in the temperature of the cycle.

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MATERIAL HANDLING
a) General
i) When stacking material, be sure that the stacks are not over balanced, or lopsided and the foundation is level and solid. ii) Gloves must be worn when handling rough materials, such as barrels, drums, steel, boxes, brick, etc. iii) All operating personnel must wear safety shoes. These may be obtained though your block in charge and the safety section. iv) Two wheeled hand trucks should be pushed, not pulled, in order to avoid catching the heel of the operator. Only four wheeled trucks with swivel axles and long tongue handles are safe to be pulled. v) Drive ways, platforms, walks, stairways or ladders must not be obstructed with any materials, such as ropes, lines or supplies. vi) At the completion of a job all scaffolds, ladders, materials, scraps, tools, etc. must be removed. vii) viii) In moving drums, wear gloves and grip chimes on top, never roll drums with feet. To up-end drums, stand close to end, place feet slightly apart, grip underside of drum end with hands about eight inches apart. BEND KNEES AND LIFT WITH YUOUR LEGS. ix) Remove, cut off, or hammer down protruding nails, staples or steel strip in boxes or barrels before you reach site.

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b)

HANDLING OF SOLVENTS

Most of the organic solvents used in the factory are flammable liquids. These liquids are easily ignited and fairly difficult to extinguish, since they burn with great rapidity. Vapors of these low boiling liquids also pose a high inhalation risk and a majority of these solvents therefore warrants strict adherence to the instructions summarized below, in order to minimize fire hazards as well as to ensure operator safety.

GENERAL PRECAUTIONS
1. 2. 3. 4. Solvents must be stored in good containers and not in rusty/damaged drums. Do not expose drums containing low boiling liquids to direct sun. Do not store acids and other hazardous chemicals near or above solvents drums. Drums containing solvents should not be stored on the roads between the production buildings, since these are supposed to act as fire breaks, in the event of a major fire in any building. 5. Ensure that overhead build-up of pressure in the drums (particularly those containing low boiling liquids) is released periodically (once a week) 6. Contents from bulged-out or damaged drums must be emptied out on priority, without delay. 7. Empty, damaged, rusted or bulged-out drums should be transferred to disposal yard after adequate degassing. 8. 9. 10. Do not dispense solvents in the godowns without authorization. Use proper trolley for carrying solvent drums. Filled drums of heavy liquids should be handled by two persons.

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11. 12.

Leather gloves should be worn while handling the drums. Check the approved label on a fresh solvent drum and ensure identity and status of the material before its use in the process.

13.

Containers used for storing passed material or freshly distilled liquids should be appropriately stenciled by base plant for identification of the material, after defacing earlier markings. Do not affix MANILA TAGS (Yellow labels) which are likely to peel off/lose the identity markings.

14.

Ensure that Pass/identity labels affixed to the containers are removed/defaced as the material is emptied out.

15.

Use proper opener made of brass that engages the lid securely. Do not use a screwdriver or other implements for this purpose.

16.

A drum where the lid cannot be opened with normal force, due to either rusty nature or long standing of the drum should be opened in an open area under the instructions of the supervisor. Do not attempt to open such containers using chisel and hammer.

17.

Use metal containers for transferring/storing solvents and not polythene/PVC buckets or bins.

18. 19. 20.

Partially filled solvent drums or containers must not be left open. Never fill the containers up to the brim. During transfer operation, minimize free fall of the liquid to avoid excessive generation of the solvent of the solvent vapors and also build-up of static electricity.

21.

Flexible hosed and polythene tubes used for solvent transfer must be securely bonded/earther by copper or aluminum wire and clips, to prevent static build-up.

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22. 23.

Do not use compressed air to blow off flammable solvents from receivers or tanks. Operator must use safety wear such as face sheild, apron and gloves during hot/pressure filtration or solutions containing solvents.

24.

Solvents spillages on the floor should be dealt with promptly and the soiled overalls/suits washed with water. Change the wear, if necessary.

25. 26. 27.

The person attending to floor spillages of solvents must wear appropriate safety equipment. Solvents and their residues must not be thrown into sinks and the factory drains. Solvents residues and non-recoverable distillates should not be allowed to accumulate in large quantities but disposed of quickly by burning in designated areas (incinerator), following the factory procedure.

28.

Apply barrier cream on hands and face regularly after duty hours to prevent drying of the skin due to exposure or possible contact with solvents.

c)

HANDLING OF ACIDS AND ALKALIS

GENERAL
1. Avoid direct contact with acids and alkalis if contact takes place wash the affected part with large amount of water. Get treatment at Occupational Health Centre IMMEDIATELY.. 2. Use carbouys trucks for moving carbouys. Carbouys should never be handled by the closer on neck of the bottle or walked on the edge of the box. Carbouys should never be moved unless securely stoppered and wired. 3. When a carbouys is opened, the wire on the stopper of the carbouys should be cut. Do not twist the wire or pry the stopper.

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4. 5. 6.

When filling containers, leave ample air space above the liquid for expansion. Never add water to concentrated acids. Add the acid to water slowly. Tilters or siphons should be used in removing acids from carbouys. Never use air pressure or tilt by hand.

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Safety Interlocks
The interlock switch is a means of safeguarding that monitors the position of a guard or gate. An interlocked guard can be used to shut off power, control personnel access, and can prevent the machine from starting when the guard is open. You'll be interested in this tutorial if you are: • • • Exploring safeguards for your hazard Deciding between types of interlocking switches Planning on installing an interlocked guard or gate

Interlocking is a method of preventing undesired states in a state machine, which in a general sense can include any electrical, electronic, or mechanical device or system. In most applications an interlock is a device used to help prevent a machine from harming its operator or damaging itself by stopping the machine when tripped. Household microwave ovens are equipped with interlock switches which disable the magnetron if the door is opened. Similarly household washing machines will interrupt the spin cycle when the lid is open. Interlocks also serve as important safety devices in industrial settings, where they protect employees from devices such as robots, presses, and hammers. While interlocks can be something as sophisticated as curtains of infrared beams and photo detectors, they are often just switches.

Mechanical
Interlocks may be strictly mechanical, as in the internal safety of a firearm that prevents release of the firing pin unless the chamber is properly closed. In the operation of a device such as a press or cutter that is hand fed or the workpiece hand removed, the use of two buttons to actuate the device, one for each hand, greatly reduces the possibility of operation endangering the operator. No such system is fool-proof, and such

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systems are often augmented by the use of cable–pulled gloves worn by the operator; these are retracted away from the danger area by the stroke of the machine. A major problem in engineering operator safety is the tendency of operators to ignore safety precautions or even outright disabling forced interlocks due to work pressure and other factors. Therefore such safeties require and perhaps must facilitate operator cooperation. A Safety Instrumented System (SIS) is a form of process control usually implemented in industrial processes, such as those of a factory or an oil refinery. The SIS performs specified functions to achieve or maintain a safe state of the process when unacceptable or dangerous process conditions are detected. Safety instrumented systems are separate and independent from regular control systems but are composed of similar elements, including sensors, logic solvers, actuators and support systems. The specified functions, or safety instrumented functions (SIF) are implemented as part of an overall risk reduction strategy which is intended to reduce the likelihood of identified hazardous events involving a catastrophic release. The safe state is a state of the process operation where the hazardous event cannot occur. The safe state should be achieved within one-half of the process safety time. Most SIF are focused on preventing catastrophic incidents.

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Ventilation
Ventilating (the V in HVAC) is the process of "changing" or replacing air in any space to provide high indoor air quality (i.e. to control temperature, replenish oxygen, or remove moisture, odors, smoke, heat, dust, airborne bacteria, and carbon dioxide). Ventilation is used to remove unpleasant smells and excessive moisture, introduce outside air, to keep interior building air circulating, and to prevent stagnation of the interior air. Ventilation includes both the exchange of air to the outside as well as circulation of air within the building. It is one of the most important factors for maintaining acceptable indoor air quality in buildings. Methods for ventilating a building may be divided into mechanical/forced and natural types.[1] "Mechanical" or "forced" ventilation is used to control indoor air quality. Excess humidity, odors, and contaminants can often be controlled via dilution or replacement with outside air. However, in humid climates much energy is required to remove excess moisture from ventilation air. Kitchens and bathrooms typically have mechanical exhaust to control odors and sometimes humidity. Factors in the design of such systems include the flow rate (which is a function of the fan speed and exhaust vent size) and noise level. If ducting for the fans traverse unheated space (e.g., an attic), the ducting should be insulated as well to prevent condensation on the ducting. Direct drive fans are available for many applications, and can reduce maintenance needs. Ceiling fans and table/floor fans circulate air within a room for the purpose of reducing the perceived temperature because of evaporation of perspiration on the skin of the occupants. Because hot air rises, ceiling fans may be used to keep a room warmer in the winter by circulating the warm stratified air from the ceiling to the floor. Ceiling fans do not provide ventilation as defined as the introduction of outside air. Natural ventilation is the ventilation of a building with outside air without the use of a fan or other mechanical system. It can be achieved with openable windows or trickle vents when the 92

spaces to ventilate are small and the architecture permits. In more complex systems warm air in the building can be allowed to rise and flow out upper openings to the outside (stack effect) thus forcing cool outside air to be drawn into the building naturally through openings in the lower areas. These systems use very little energy but care must be taken to ensure the occupants' comfort. In warm or humid months, in many climates, maintaining thermal comfort solely via natural ventilation may not be possible so conventional air conditioning systems are used as backups. Air-side economizers perform the same function as natural ventilation, but use mechanical systems' fans, ducts, dampers, and control systems to introduce and distribute cool outdoor air when appropriate.

Definition
Ventilation is the intentional movement of air from outside a building to the inside. Ventilation air, as defined in ASHRAE Standard 62 and the ASHRAE Handbook, is that air used for providing acceptable indoor air quality. It mustn't be confused with vents or flues; which mean the exhausts of clothes dryers, and combustion equipment such as water heaters, boilers, fireplaces, and wood stoves. The vents or flues carry the products of combustion which have to be expelled from the building in a way which does not cause harm to the occupants of the building. Movement of air between indoor spaces, and not the outside, is called transfer air.

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An example of closed ventilation
In commercial, industrial, and institutional (CII) buildings, and modern jet aircraft, return air is often recirculated to the air handling unit. A portion of the supply air is normally exfiltrated through the building envelope or exhausted from the building (e.g., bathroom or kitchen exhaust) and is replaced by outside air introduced into the return air stream. The rate of ventilation air required, most often provided by this mechanically-induced outside air, is often determined from ASHRAE Standard 62.1 for CII buildings, or 62.2 for low-rise residential buildings, or similar standards.

Necessity
When people or animals are present in buildings, ventilation air is necessary to dilute odors and limit the concentration of carbon dioxide and airborne pollutants such as dust, smoke and volatile organic compounds (VOCs). Ventilation air is often delivered to spaces by mechanical systems which may also heat, cool, humidify and dehumidify the space. Air movement into buildings can occur due to uncontrolled infiltration of outside air through the building fabric (see stack effect) or the use of deliberate natural ventilation strategies. Advanced air filtration and treatment processes such as scrubbing, can provide ventilation air by cleaning and recirculating a proportion of the air inside a building.

Types of ventilation


Mechanical or forced ventilation: through an air handling unit or direct injection to a space by a fan. A local exhaust fan can enhance infiltration or natural ventilation, thus increasing the ventilation air flow rate.

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Natural ventilation occurs when the air in a space is changed with outdoor air without the use of mechanical systems, such as a fan. Most often natural ventilation is assured through operable windows but it can also be achieved through temperature and pressure differences between spaces. Open windows or vents are not a good choice for ventilating a basement or other below ground structure. Allowing outside air into a cooler below ground space will cause problems with humidity and condensation.



Mixed Mode Ventilation or Hybrid ventilation: utilises both mechanical and natural ventilation processes. The mechanical and natural components may be used in conjunction with each other or separately at different times of day. The natural component, sometimes subject to unpredictable external weather conditions may not always be adequate to ventilate the desired space. The mechanical component is then used to increase the overall ventilation rate so that the desired internal conditions are met. Alternatively the mechanical component may be used as a control measure to regulate the natural ventilation process, for example, to restrict the air change rate during periods of high wind speeds.



Infiltration is separate from ventilation, but is often used to provide ventilation air.

Ventilation rate
The ventilation rate, for CII buildings, is normally expressed by the volumetric flowrate of outside air being introduced to the building. The typical units used are cubic feet per minute (CFM) or liters per second (L/s). The ventilation rate can also be expressed on a per person or per unit floor area basis, such as CFM/p or CFM/ft², or as air changes per hour. For residential buildings, which mostly rely on infiltration for meeting their ventilation needs, the common ventilation rate measure is the number of times the whole interior volume of air is replaced per hour, and is called air changes per hour (I or ACH; units of 1/h). During the winter, ACH may range from 0.50 to 0.41 in a tightly insulated house to 1.11 to 1.47 in a loosely insulated house.

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ASHRAE now recommends ventilation rates dependent upon floor area, as a revision to the 62-2001 standard whereas the minimum ACH was 0.35, but no less than 15 CFM/person (7.1 L/s/person). As of 2003, the standards have changed to an addition of 3 CFM/100 sq. ft. (15 l/s/100 sq. m.) to the 7.5 CFM/person (3.5 L/s/person) standard.

Ventilation standards


In 1973, in response to the 1973 oil crisis and conservation concerns, ASHRAE Standards 62-73 and 62-81) reduced required ventilation from 10 CFM (4.76 L/S) per person to 5 CFM (2.37 L/S) per person. This was found to be a primary cause of sick building syndrome.



Current ASHRAE standards (Standard 62-89) states that appropriate ventilation guidelines are 20 CFM (9.2 L/s) per person in an office building, and 15 CFM (7.1 L/s) per person for schools. In commercial environments with tobacco smoke, the ventilation rate may range from 25 CFM to 125 CFM.

In certain applications, such as submarines, pressurized aircraft, and spacecraft, ventilation air is also needed to provide oxygen, and to dilute carbon dioxide for survival. Batteries in submarines also discharge hydrogen gas, which must also be ventilated for health and safety. In any pressurized, regulated environment, ventilation is necessary to control any fires that may occur, as the flames may be deprived of oxygen. ANSI/ASHRAE (Standard 62-89) sets maximum CO2 guidelines in commercial buildings at 1000 ppm, however, OSHA has set a limit of 5000 ppm over 8 hours. Ventilation guidelines are based upon the minimum ventilation rate required to maintain acceptable levels of bioeffluents. Carbon dioxide is used as a reference point, as it is the gas of highest emission at a relatively constant value of 0.005 L/s. The mass balance equation is:
Q = G/(Ci − Ca) • • •

Q = ventilation rate (L/s) G = CO2 generation rate Ci = acceptable indoor CO2 concentration

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Ca = ambient CO2 concentration[9]

Ventilation equipment
• • • • •

Fume hood Biological safety cabinet Dilution ventilation Room air distribution Heat recovery ventilation

Natural ventilation
Natural ventilation involves harnessing naturally available forces to supply and removing air through an enclosed space. There are three types of natural ventilation occurring in buildings: wind driven ventilation, pressure-driven flows, and stack ventilation. The pressures generated by 'the stack effect' rely upon the buoyancy of heated or rising air. wind driven ventilation relies upon the force of the prevailing wind to pull and push air through the enclosed space as well as through breaches in the building’s envelope (see Infiltration (HVAC)). Natural ventilation is generally impractical for larger buildings, as they tend to be large, sealed and climate controlled specifically by HVAC systems. Both are examples of passive engineering and have applications in renewable energy.

Demand-controlled ventilation (DCV)
DCV makes it possible to maintain proper ventilation and improve air quality while saving energy. ASHRAE has determined that: "It is consistent with the Ventilation rate procedure that Demand Control be permitted for use to reduce the total outdoor air supply during periods of less occupancy. CO2 sensors will control the amount of ventilation for the actual number of occupants. During design occupancy, a unit with the DCV system will deliver the same amount of outdoor air as a unit using the ventilation-rate procedure. However, DCV can generate substantial energy savings whenever the space is occupied below the design level.

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Local exhaust ventilation
Local exhaust ventilation addresses the issue of avoiding the contamination of indoor air by specific high-emission sources by capturing airborne contaminants before they are spread into the environment. This can include water vapor control, lavatory bioeffluent control, solvent vapors from industrial processes, and dust from wood- and metal-working machinery. Air can be exhausted through pressurized hoods or through the use of fans and pressurizing a specific area. A local exhaust system is composed of 5 basic parts 1. A hood that captures the contaminant at its source 2. Ducts for transporting the air 3. An air-cleaning device that removes/minimizes the contaminant 4. A fan that moves the air through the system 5. An exhaust stack through which the contaminated air is discharged

Ventilation and combustion
Combustion (e.g., fireplace, gas heater, candle, oil lamp, etc.) consumes oxygen while producing carbon dioxide and other unhealthy gases and smoke, requiring ventilation air. An open chimney promotes infiltration (i.e. natural ventilation) because of the negative pressure change induced by the buoyant, warmer air leaving through the chimney. The warm air is typically replaced by heavier, cold air. Ventilation in a structure is also needed for removing water vapor produced by respiration, burning, and cooking, and for removing odors. If water vapor is permitted to accumulate, it may damage the structure, insulation, or finishes. When operating, an air conditioner usually removes excess moisture from the air. A dehumidifier may also be appropriate for removing airborne moisture. Problems

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In hot, humid climates, unconditioned ventilation air will deliver approximately one pound of water each day for each cubic foot per minute of outdoor air per day, annual average. This is a great deal of moisture, and it can create serious indoor moisture and mold problems.


Ventilation efficiency is determined by design and layout, and is dependent upon placement and proximity of diffusers and return air outlets. If they are located closely together, supply air may mix with stale air, decreasing efficiency of the HVAC system, and creating air quality problems.



System imbalances occur when components of the HVAC system are improperly adjusted or installed, and can create pressure differences (too much circulating air creating a draft or too little circulating air creating stagnancy).



Cross-contamination occurs when pressure differences arise, forcing potentially contaminated air from one zone to an uncontaminated zone. This often involves undesired odors or VOCs.



Re-entry of exhaust air occurs when exhaust outlets and fresh air intakes are either too close, or prevailing winds change exhaust patterns, or by infiltration between intake and exhaust air flows.



Entrainment of contaminated outside air through intake flows will result in indoor air contamination. There is a variety of contaminated air sources, ranging from industrial effluent to VOCs put off by nearby construction work.[13]

Air Quality Procedures
Ventilation Rate Procedure is rate based on standard, and “prescribes the rate at which ventilation air must be delivered to a space and various means to condition that air.”[14] Air quality is assessed (through CO2 measurement) and ventilation rates are mathematically derived using constants.

Indoor Air Quality Procedure “uses one or more guidelines for the specification of acceptable concentrations of certain contaminants in indoor air but does not prescribe ventilation rates or

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air treatment methods.”[14] This addresses both quantitative and subjective evaluation, and is based on the Ventilation Rate Procedure. It also accounts for potential contaminants that may have no measured limits, or limits are not set (such as formaldehyde offgassing from carpet and furniture

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Fire safety
Sources of ignition
Sources of energy can be classed into 4 categories: Flames and smouldering Under this heading come all naked flames: as the evident ones such as welding torches, matches, and gas burners, and sporadic sources as for example the exhaust of an engine. Smouldering covers all forms of incandescent material such as cigarettes, and less obviously, catalysts. Hot surfaces Hot surfaces occur widely in industry and may cause ignition of flammable solvent/air mixtures either directly or indirectly. Direct ignition will occur if the surface is at a temperature above the auto-ignition temperature of the solvent –air mixture in the particular conditions considered. Indirect ignition results from the burning or smouldering of material initiated by a hot surface. Hot surfaces are widespread in industrial areas: as examples, walls of ovens and furnaces, electrical equipment, and heating pipes. Some operations can easily produce hot spots: as examples, grinding, cutting and welding operations. Safe Working with Industrial Solvents Friction and impact Hot surfaces and incandescent sparks mainly arise from friction, and depend largely on the materials: for example, sparks produced during impacts involving metals (magnesium and their alloys, iron) with grit or rock generate high heat.

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Electrical discharges There is specific legislation aimed at ensuring that operators have adequately considered the risks posed by electricity. The regulations require operators to classify their sites in terms of zones. Electrical discharges are widespread and often hidden. They usually arise from two basic sources:

Electrical power
"Main grid electricity as well as batteries are sources of sparks with sufficient energy to ignite solvent vapours-air blends: normal operations of transformers, motors, circuit breakers, switches, fuses as well as electrical failures such as damaged cables are common electrical ignition sources. Electromagnetic waves emitted by radio antennae may give rise to sparks in their vicinity or to a heat build-up of materials. Electrostatic discharges "Static electricity is a phenomenon of great importance when handling solvents, in articular hydrocarbon solvents. This is such an important source of incidents that the final part of this guide is fully dedicated to this aspect.

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Inertisation procedure
Inertisation is nothing but the removal of oxygen from the reactor vessel/flammable atmosphere and filling the vessel with inert gases viz. Nitrogen and Helium etc. In chemical manufacturing companies nitrogen is widely used inert gas to make inert atmosphere in vessel. Procedure for inertisation is give below. 1. Reactor and centrifuges handling flammable liquids / gases/ powders are provided with nitrogen supply 2. Before charging of flammable, static electricity prone materials in to the reactor containing air/oxygen it is to be inerted as below a. Remove all the existing gases in the reactors by vacuum and maintain 400 mm hg. b. Break the vacuum with nitrogen and pressure rise the reactor 0.5 kg/cm2 3. While withdrawing process mass from reactor to centrifuge required nitrogen flow shall be provided through rotometer to ensure that only nitrogen displaces process mass and atmospheric air is nit allowed in. 4. During centrifugation, we shall ensure that the vessel lid is closed in air tight manner such that atmospheric air is not sucked in and nitrogen bleed is maintained.

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Electrical safety
'Electricity is a good servant but a bad master'. Electricity is not all dangerous if it is properly used and if electrical equipments are properly installed operated and maintained. Electricity if not adequately controlled may present following hazards. Primary Hazards 1 Dangers from direct contact a. b. 2 Electric shock Internal burn

Hazards without current flowing through body a. b. Flash over burns - Air getting ionized Radiation burns - Electric Arcs

3

Fire and Explosion due to a. b. Electric Ignition Static electricity

4

Intense electromagnetic fields (Current flow induced in or near the human body) a. b. c. Electrocution of whole body temperature Cataract formation in the eye Burns due to metallic objects such as rings, dental metal etc.

Secondary Hazards Injury due to false starting of machine drives involuntary reflex actions. a. b. Persons falling from heights Dropping of tools and objects

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Electric Shock
Electric shock occurs when the body becomes part of the electric circuit. The current must enter the body at one point and leave at another. Shock may occur in one of the three ways. 1. 2. 3. With both wires of electric circuit. With one wire of an energized circuit & the earth With a metallic part that has become hot by itself being in contact with an energized wire. Factors Affecting Severity of Electric Shock The severity of injuries sustained in any given case due to use of electricity depends upon several factors. The Nature of Current - whether A.C. or D.C. Alternative current is more dangerous than Direct current for a given voltage since A.C. causes titanic contractions of muscles. The risk of electric shock is less with D.C. than with A.C. However, burn risk with D.C. may be greater. The Frequency of Alternating Current The frequency capable of causing electric shock can vary from 10 to 130 cycles per second. The Amperage of Current The range of amperage of current capable of causing ventricular fibrillation is between 70 mA and 4 A. The Circuit Voltage The resistance of the body depends upon the circuit voltage and tends to decrease as the voltage increases. High voltage rapidly cause high temperatures and can cause serious

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burns. In practice, the risk of fibrillation is greatest with shocks between 300 and 800 volts, but may be present from 60 to 2000 V. The Path of the Current through Body The most dangerous path from the point of view of ventricular fibrillation is right arm and left leg, though other limb path may also be dangerous because of derived currents. The Duration of Electric Shock A shock lasting 1 to 3 seconds is sufficient enough to cause ventricular fibrillation. Duration of shock that is not sufficient to cause ventricular fibrillation may cause spasm of respiratory muscles.

Resistance of the Subject This varies from 100 ohms to 6,00,000 ohms, depending upon the nature of the skin or the part affected, whether it is hard, soft, dry or wet and varies also with the covering of the skin, clothes, shoes, gloves safety helmets worn etc. The Phase of the Cardiac Cycle at which the Current Passes The heart normally beats at 70 rates per minute, each beat is composed of a number of events within the heart and after each beat, there is short rest period of about fraction of a second. A current passing through this rest period is more liable to cause ventricular fibrillation than one passing while the ventricles are beating.

Electrical Quantities Associated with Human Injury Flow of electricity through human body depends upon the voltage of the circuit and the quantum of the resistance offered by the body parts.

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a.

Human Resistance to Electric Current Resistance in Ohms 100,000 to 600,000 1,000 400 to 600 About 100

Body Area/condition Dry skin Wet skin Internal body (Hand to foot) Ear to Ear Effect of Electric Current on Man Effect 1 2 Slight sensation on hand Shock-not painful, muscular control not 3 lost Shock-painful, muscular control not 4 lost Shock-painful and severe muscular contraction, breathing difficult 90 60 62 41

Current in Millamperes Direct 60 Hz A.C. Men Women Men Women 1 0.6 0.4 0.3 9 6 1.8 1.2

9

6

23

15

The above values also depend on the frequency of alternating current; with lower frequencies the safe value of current would be higher. 24 Volts is the safest limit for voltage.

LIGHTNING PROTECTION:

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Lightning is a huge spark of very high potential lightning occurs when the clouds are attack each other by heavy force and friction, as a result there is a spark of very high potential and intensity. This is happens frequently during monsoon seasons. The lightning stock to earth (ground) is very dangerous, because due to lightning there is loss of property and damage the environment hence the protection against lighting is required to reduce its effect. The principle for the protection of property and environment against lightning is to provide a conducting path between the earth and atmosphere above property by which a lighting discharge may enter the earth without producing dangerous potential in or near by property. The installation of lightening arrestors is the most popular and effective way of protection against lightning. The required conditions for installation protection are met by placing all the terminals in the form of vertical horizontal conductor on the topmost part of the building / structure with lightning conductors. Connecting the terminal with the earth The material of lightning arrestor, conductors, earth electrode etc. of protective system shall be reliable resistant to corrosion. The following materials are recommended. 1. 2. 3. 4. Copper Galvanized steal Copper clad steel Aluminum

Generally copper and galvanized steel are used. The lightning protective system of direct path is the best to discharge the lightning stroke and should have as few joints in it. In the down conductor to ground level.

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There should be no joints. Where the joints are necessary. They shall be mechanically and electrically effective, maybe clamped, screwed, and bolted, crimped or welded. Where the overlap is come then clamped both surface first and then inhibited from oxidation with suitable non corrosive compound only the last point’s joint shall be of clamped or bolted. Other joints are soldered, welded or brazed. The properly made earth connections are essential to effective functioning of lightning protection system and every effort should be made provide ample contact with earth, the earth resistance also kept as low as possible. The each earth termination should have resistance in ohms to earth not exceeding10 ohms, and if the value exceeds 10 ohms the reduction may be achieved by installing addition earth electrodes by interconnecting the earth termination. As a last resort a temporary reduction in soil resistivity may be achieved by chemical treatment of soil to reduction of earth resistance below 10 ohms. The lightning protection system is required to reduce the loss of property as well as the environment. Hence lightning protection system essential in industries, buildings, generating stations substations etc.

Electrical zoning
Classification of Hazardous Area

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To determine the type of electrical installation applicable to a particular situation, the hazardous areas have been divided into three Zones viz. Zone 0, Zone 1 and Zone 2 according to the degree of probability of the presence of hazardous atmosphere. Typical examples are given below: Zone 0 areas Vapour space above closed process vessels, storage tanks and containers. It also includes areas containing open tanks of volatile flammable liquid. Zone 1 areas Zone 1 locations may be distinguished when any of the following conditions exists: 1. Flammable gas or liquid concentration is likely to exist in the air under normal operating conditions, 2. Flammable atmospheric concentration is likely to occur frequently because of maintenance repairs or leakage. 3. Flammable liquid or vapour piping system (containing valves, meters or screwed or flange fittings) is in an inadequately ventilated area. 4. The area below the surrounding elevation or grade is such that flammable liquids or vapours may accumulate therein. The classification typically includes (but not limited to): ♦ Reactor areas, Centrifuge areas ♦ Inadequately ventilated pump rooms for volatile flammable liquids or

flammable gases. ♦ Interiors of refrigerators and freezes in which volatile flammable materials

are stored in lightly stoppered containers ♦ ⇒ Storage and Loading / unloading areas of flammable materials Zone 2 areas

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Zone 2 locations may be distinguished when any one of the following conditions exists: ♦ Locations adjacent to Zone 1 areas ♦ Escape of flammable material or gas from a closed system, in an adequately ventilated area, during abnormal conditions such as failure of a gasket or packing ♦ Flammable vapours can flow to the location such as trenches, pipes or ducts ♦ Failure of positive mechanical ventilation

Areas not Classified In general following locations are considered safe from the point of view of electrical installations: ♦ Areas where the piping system is without valve, flanges, fittings etc. ♦ Areas where flammable liquids or gases are transported only in suitable containers or vessels ♦ Areas where permanent ignition sources like flare tips, other open flames, boiler and hot surfaces (Consideration should be given, however to potential leak sources in pumps, valves etc. and fuel lines feeding flame or heat producing equipment to avoid installing electrical devices which then become primary ignition source for such leaks. Lack of classification around unprotected fired vessel does not imply the safe placement of fired vessel in the proximity of other production equipment.) ♦ Diesel generator rooms having adequate ventilation

Properties of flammable material
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Flammable substances for electrical installations include non liquefiable gases, liquefied petroleum gases and vapours of flammable liquids. Flammable liquids are divided into three categories: ♦ ♦ ♦ Class A : Flammable liquids having flash point below 23 C Class B : Flammable liquids having flash point below 65 C Class C : Flammable liquids having flash point below 93 C

Normally Class A and Class B liquids will produce vapours considered to be in the flammable range for electrical design purposes. Class C liquids having flash point below 93 C should be considered as producing flammable vapours when handled, processed or stored under such conditions that the temperature of the liquid when released to the atmosphere could exceed its flash point.

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GENERAL SAFETY RULES & GUIDELINES          Keep the work place clean and tidy. Wear/Use the prescribed protective clothing/equipment. Report all accidents, however minor they may. Report all near misses, what ever you feel Learn to render first aid. Don’t start machinery or equipment unless authorized to do so. Use correct tools & equipment, which are in good condition. Don’t leave tools on the floor or from where they can fall on people below. Before starting a job, be sure that you know how to do it safety and efficiently. If in doubt, consult your superior. Always ask yourself: ”What can to wrong”? .    water coolers.   Do not walk through or cross any operating plant unless your duty requires to do so. Do not sleep in the plant premises. It could be dangerous. EVACUATION  It is the plants responsibility to have the building and site evacuation procedure posted at all times in conspicuous places.  EXITS  Fire doors, exits, stairways and aisles must be clearly marked and kept free of all obstructions. TRAVEL WITHIN SITE    Riding on hydraulic lifts, on rear of truck forks of the forklifts is prohibited. While driving any vehicle, observe the prescribed speed limits of 15 km/hr. Do not rest under or close to any vehicle. 113 Know the evacuation procedure of the building in which you are working. Don’t make changes with out clear instructions– follow the instructions. Report all unsafe conditions and unsafe acts. Do not use service water for drinking purpose. Drinking water should be taken only from



Place wheel-chocks on both ends of rear wheels of the parked vehicles. ELEVATORS Familiarize yourself and comply with the rules concerning the respective elevators. Do not clean elevator with water. FALL AND COLLISIONS  Watch your step on stairs. Use hand-rail .  Do not carry too much load on stairs.  Reading while walking or using stairs is dangerous.  Do not run-walk; it is safer for everybody. HOUSEKEEPING Good housekeeping and tidiness helps in:  Reducing accidents and incidents.  Keeping floors, passages and stairs clean.  Avoiding a tripping hazard by placing waste bins in the right place. INSTRUCTIONS Keep aisles and working areas clear. Do not block exits, safety showers, fire Do not leave hoses and tools on the floor. Do not keep nuts, bolts and gaskets on top of vessels. Keep them in proper places Soiled gloves, cotton waste and other disposable must be disposed in containers Stack empty drums in neat rows. Clean up any spillage immediately. Consult supervisor for proper method when in



equipment and panel rooms.   provided.  provided for this purpose.   doubt.

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FIRE Never fight with fire, unless you are well trained in fire fighting and usage of fire  Just escape from the fire area and shout “FIRE-FIRE-FIRE”  Familiarize your self with the location of fire alarms, fire extinguishers, fire hose and Do not block the fire fighting equipment or access to it.  Learn the use of extinguishers.  Before using a fire extinguisher make sure it is of the correct type.  After a fire extinguisher is used notify security officer.  Dial security 200/201 or sound alarm in case of fire.  In case of fire, collect outside at a safe spot.  Leave fire fighting to the properly trained persons. Do not create confusion.  Never dispose of smoking materials in the waste paper basket.  Keep the containers of flammable liquids tightly closed. TYPES OF FIRE & FIRE EXTINGUISHERS  Class A fires: Fires involving solid combustible materials of organic nature such as wood, paper, rubber, plastics, etc. Where the cooling effect of water is essential for extinction of fires.  Use water expelling type extinguishers.  Class B fires: Fires involving flammable liquids or liquefiable solids or the like where a blanketing effect is essential.  Use foam, dry powder or carbon dioxide extinguishers.  Class C fires: Fires involving flammable gases under pressure including liquefied gases, where it is necessary to inhibit the burning gas at fast rate with an inert gas.  Use dry powder, vaporizing liquid & carbon dioxide extinguishers. gas masks in your building. 

 extinguishers

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 Class D fires: Fires involving combustible metals, such as magnesium, aluminum, zinc, sodium, potassium, etc., when the burning metals are reactive to water and water containing agents and in certain ases carbon dioxide, halogenated hydrocarbons and ordinary dry powders. These fires require special media and techniques to extinguish.  Use special dry chemical powder for metal fires LUNCH ROOM/CANTEEN  The canteen is located on the ground floor of the administration building. Under no Always wash hands thoroughly before eating. Drinking water facility is provided in all the plants. NEVER DRINK WATER FROM A HOSE OR SINK WEARING APPAREL  dangerous.   Never carry rags or oily waste in your pockets. Hoods or face shields must be worn while transferring acid/alkalis or liquid chemicals Goggles or face shields, rubber aprons, rubber gloves and rubber over shoes must be Respirator or other special protective equipment must be worn where indicated in the The clothes you wear must be clean. Dirty or greasy clothing is unhealthy and circumstances should lunch be eaten in other than designated places.   

to or from drums, or any other open container.  used while handling liquids in other than permanent lines.  process or when instructed by supervisor to do so. REQUIREMENT OF PPE’S Consider the following factors before deciding upon the personal protective equipment:  Nature of the hazard.  Severity of the hazard.  Type of contaminant.  Concentration of the contaminant.

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 Location of the contaminated area with respect to the source of repairable air.  Duration of work (exposure time).  Expected activity of the wearer.  Operating characteristics and limitations of the PPE.  The PPE should be appropriately chosen, depending on the situation & just check the PPEs before using. SAFETY SIGNS/TAGS  Comply with all warning signs and safety posters displayed at site.  Repair tags are placed on motor drivers pumps, reactors and other machinery to UNDER NO CIRCUMSTANCES OPERATE EQUIPMENT CARRYING A protect all workman. These tags can be removed only by those responsible for repairs.  REPAIR TAG. GENERAL ABOUT CHEMICALS  Chemicals must be recognized for what they are and must be respected as such, safe  All chemicals can be used and handled safely, provided that.  We keep in mind that many of them can cause personal injury.  We follow safe practices and established precautions. MATERIAL HANDLING  Before lifting, get a good grip, and make sure of your footing. Get help if needed.  Never carry a large object alone.  While walking with load, make sure that forward view is clear.  Never handle anything with greasy gloves.  In case of stacked material, take from top of the pile.  Make sure to use good condition pallets.  Store flammable materials in specified areas. LIFTING OF MATERIAL 118 working in a chemical plant requires acceptance of this rule without question.

Most of the back injuries can be prevented if correct lifting methods are employed by fully utilizing the strong leg muscles rather than weak back muscles. Remember the following guidelines. Size up the load. Do not try to lift/push objects, which are too heavy for you. When two or more employees are carrying an object, do not drop your share of load Keep arms close to the body. Bend knees and keep back straight. Look out for any sharp object. Use proper personal protective equipment. Position feet correctly,25-30 cm apart, close to the load with one foot ahead of the Take firm grip on the object. If possible, grasp the object from bottom, using your Lift the object by straightening the leg, by giving an upward thrust. Reverse the procedure while lowering the load. DRUM OR BARREL HANDLING   of drum.       injury to fingers. Check the label to find nature of material stores in drum. Use drum trolley or other mechanical equipment for transportation. Never roll the filled drum. Use always drum trolley Take the help of other, if required. If drum is to be placed in vertical position ask for assistance. Always allow enough space between barrels, drums, walls and columns to prevent Inspect, if there has been any spillage or leakage due to physical damage. If so, inform supervisor, seek instructions for removing spilled material and handling

  

without first warning the other.    

other in the direction of movement.  palm and not finger tips .  

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While removing bung from a drum loosens gradually, so as to allow pressure to While using open barrels do not fill more than two thirds. This shall help in reducing Empty drums which have contained hazardous / toxic material must have cover/bung Always follow special instruction listed on the manufacturer’s label. Never hammer the caps/lids of drums if you are unable to remove. Always use proper lid remover. Spark may cause severe explosion of drum CARBOYS Inspect each carboy to make sure that the stopper is securely fastened. Do not stack carboys on their sides or more than two high. Carboys are not to be dropped or “walked” by rolling. Use pallets and pallet truck or Carboys containing flammable liquids must be kept away from sparks and open Never handle a carboy by neck or remove stopper by prying. Never use air pressure to remove contents of a carboy. When emptying carboys into pails, a tilting device and pouring spout must be used. Drain carboys thoroughly and replace the stopper and cap. There is no such thing as a empty carboy. Handle each one with care. Always observe the special precautions listed on manufacturer’s lable. Don’t hit the carboy at any time USE OF FORK- LIFTS  Do not move with insecure loads. 120

escape before bung is finally removed.  spillage/hazards.  replaced and tightened snug so that small amount left in drum shall not spill out.    

  

fork lift to shift them.  flames.       

 Do not overload, it can result in a serious mishap.  Slow down at cross aisle, exits and blind corners.  Travel with load low and fully tilted back.  Keep clear view and look in the direction you are traveling.       Stop and start smoothly, look out for pedestrians. Travel at safe speeds, consistent with conditions. Stop at face of stack and raise load to stacking height with load still tilted back. Move load over the stack, bring must to vertical and lower until forks are free of load. Withdraw and lower forks just clear of floor before traveling away. When truck is to be left unattended set the parking brake, with forks on the ground. Only those familiar with operation should operate the fork – lift trucks. Be extremely cautious when driving on wet or slippery floors. Do not use fork – lifts to elevate employees to work at heights. Fork – lifts are designed to carry the operator only. CARRYING OF RIDERS IS

Remove starter key.    

STRICTLY PROHIBITED. OPERATING EQUIPMENT Do not operate any equipment with which you are not familiar, unless in an Do not turn on electricity, gas, steam, air, acid, or water, or set in motion any If any tool, fixture, machine, ladder or any other piece of equipment is not in safe



emergency that requires stopping it.  machinery, without making sure that no one is in a position likely to be injured.  working order, do not use it. GUARD & SAFETY DEVICES Machine guards and other safety devices are provided for your protection. Ensure that



they are operative and in position. 121



Learn the locations of safety showers and gas masks of each building you are

required to work in.

Handling of solvents
The workplace can be made safer by following these “top ten tips” for handling solvents. 1. Understand the solvent(s) you are using and its (their) properties. This is readily seen from your suppliers’ SDS (Safety Data Sheet) which must be supplied to you for each product you use. 2. Eliminate ignition sources e.g. No smoking, Safe Systems of Work, equipment selection, minimize static build up by using suitable equipment and earthing arrangements. 3. Ensure good ventilation by working in open atmospheres (e.g. keep doors and windows open) or by using forced ventilation. 4. Work at ambient temperatures. 5. Provide information, instruction and training to all persons handling solvents. 6. Report all incidents e.g. leaks and provide clean-up and disposal facilities. 7. Provide secondary containment solutions such as bunding or oversize drums. 8. Take special precautions when loading or unloading vehicles and containers. 9. Develop a short, succinct Emergency Plan. 10. Consider inert storage solutions such as nitrogen blankets.

KEY RECOMMENDATIONS
 Operators must be trained to understand the characteristics of, and safe handling methods for, the specific solvents in use in their workplace.  Read the material-specific safety data sheets, which must be made available by suppliers.  The occurrence of flammable solvent vapours can be estimated from the flash point and the limits of flammability. 122



"A low flash point (< 55ºC) indicates a more hazardous material and the need for more care in handling. "Note that there is no link between LELs (Lower Explosion Limits) and OELs (Occupational Exposure Limits). The Auto Ignition temperature (AIT) is a very rough guide to the maximum temperature that a mixture of a flammable solvent in air can reach before selfignition. A significant safety margin must be kept between the measured AIT and the operating temperature. "The AIT is well above the boiling point of the material and there is no link between AIT and flash point. Droplet mists of solvents can be flammable at temperatures well below the flash point of the liquid. In situations where mists and sprays cannot be avoided, specific safety measures must be taken. Consult a specialist. There is a wide range of sources capable of igniting mixtures of flammable solvent vapours in air. "Most sources of ignition encountered in industrial facilities can ignite a flammable solvent vapour/air mixture (examples: spark of a calculator, mobile phone, metal tool falling on the floor). "The least obvious source of ignition and the most common source of incidents is static electricity. Hydrocarbon solvents are particularly good static electricity accumulators. Working with hydrocarbon solvents may pose more of a hazard than oxygenated solvents, because they can in their own right accumulate static electricity which may provoke sparking and subsequent fire.

















Keep solvent vapours below the Lower Explosion Limit (LEL) by:   "Working at least 15 to 20ºC below the flash point wherever possible. "Ensuring adequate ventilation: Vapours should be diluted to a level of < 25 % of the LEL (Lower Explosion Limit) value to ensure safe operation. The easiest way to assure ventilation, where it is possible, is by opening doors and windows. 123



In many cases, mechanical ventilation is necessary. Ventilation is even more important when working below flash point cannot be avoided. The ventilation exhaust should be at least 3m above the ground level and 3m. from building openings. 6 complete air changes/hour should be provided. A detector should be used in the ducts, linked to the alarm, in case of a possible extraction system failure. "Applying basic housekeeping practices: prevent unnecessary vapours by using the right amount of solvent required, and not more, by keeping lids on containers, and by using sealed containers for solvent contaminated waste. Do not leave solvent impregnated rags lying around.





Eliminate oxygen: "Use inert gas (e.g. nitrogen blanketing) to remove oxygen from the system, in particular if ignition sources cannot be totally eliminated or if hot spots cannot be avoided. Eliminate sources of ignition: Do not smoke, weld, or use naked lights in area that may contain solvents vapors.      Work permit procedures must be followed scrupulously. Use explosion-proof equipment. Eliminate hot spots. Minimize the risk of static electricity build-up Earth and bond equipment (tanks, drums, trucks, small size metal containers, using electrically conductive hoses)      Check earth resistance: it should be less than 10 ohms No splash filling Limit pipe velocity Wait to allow dissipation of charges Use conductive hoses



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If a filter is used during filling operations, a relaxation chamber should be used Switch loading can be very dangerous if compartments have not been gasfreed Do not fill products with very low flash points (< 35ºC) into plastic containers Avoid the use of compressed air for the line clearance of flammable products Wear antistatic protective clothing and footwear When working in confined spaces is unavoidable, a company-approved safe system of work must be implemented with adequate emergency arrangements, including evacuation procedures. Bear in mind that solvent vapors are heavier than air and settle in low areas. Report fault and incidents, including minor spills or leaks. The subsequent evaluation of these reports by company management should help eliminate future occurrences! Safe Working with Industrial Solvents Each year there are incidents involving solvents. DNL has evaluated the root causes of incidents in the workplace and, most frequently a lack of understanding of the nature of the solvents used, and their hazards, is at the heart of the problem.



   

 

 

Common incident causes are identified below.  Lack of training, meaning insufficient Manager/Supervisor/Operator understanding, awareness and competence  Poor control of solvent use in hot areas  Badly designed equipment or installation, leading to unnecessary emissions or even leaks  Poor selection of equipment (not suited to job)  Equipment failure  Poorly managed maintenance activities (especially in dismantling or disposal)  Low understanding of the importance of guarding against electrostatic discharges

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 Poor implementation of control procedures such as elimination of ignition sources  Heating solvents without adequate controls  Badly managed transfer operations such as filling and emptying equipment  The loading and unloading of solvents without taking adequate precautions

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Capacities of equipments (Utilities)
1. Boilers Boiler – 10 TPH - coal fired Boiler – 8 TPH - Oil Fired 2. Cooling towers 1. 500 TR - 3 Nos 2. 250 TR – 2 Nos 3. 400 TR – 4 Nos 3. Nitrogen Plant - 20 TPD 4. Chilling plant – Range from -5 Deg. Centigrade to + 10 Deg. Centigrade 5. Vapours Absorption machine - 90 TR

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Safety Check lists
Manual handling
 Have you identified all tasks involving lifting, pushing, pulling and/or carrying and assessed the risk of injury at your workplace?

 Have your risk assessments taken into account posture, movement, forces, duration, frequency and
environmental factors? (Refer to Manual Handling Code of Practice for guidance)  Are objects handled easy to grasp, have no sharp edges and are not hot, cold, slippery or bulky?  Is lifting from ground level or above shoulder level avoided?  Is the work area, equipment and system of work designed to eliminate sideways twisting of the body, excessive bending or reaching?  Is the work area, equipment and system of work designed to minimise sustained or repetitive movements?  Are mechanical handling aids provided where possible to make the task safer?  Is there enough space to allow free movement while doing the task?  Is training provided about risk factors and the proper technique to do the task?

Equipment, machinery and tools
 Is the correct equipment always used for each job?  Are all tools and machinery properly guarded?  Are stop/start switches clearly marked and positioned within easy reach of the operator?  Are operators trained to use the tools, equipment and machinery safely?  Do operators hold current licenses to perform work that requires certification?  Has provision been made to safely store or dispose waste off-cuts?  Is there enough work space around machinery?  Are tools, equipment and machinery regularly maintained (in accordance with manufacturer’s instructions)?  Is there a process to ensure that tools and machinery are switched off before maintenance and cleaning is carried out and cannot be inadvertently started by other staff during maintenance and cleaning?  Are unsafe or faulty tools, equipment or machinery reported immediately?  Are unsafe or faulty tools, equipment or machinery removed from use until they are repaired or replaced?  Are repairs always carried out by authorised and competent persons?

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 Are health and safety risks considered before modification or alteration of any tools, equipment or
machinery?

Work environment
 Is the workplace kept clean and tidy? (rubbish bins suitably located and regularly emptied,  oily rags and combustible waste kept in covered metal containers)  Is there good storage for tools, equipment, stock, products? (storage designed to minimise

 manual handling problems, easy access, shelf racks and pallets in good condition)  Have you ensured that things cannot fall onto people? (goods cannot fall from height,  shelving securely fixed and not overloaded, stacks cannot fall over, people cannot walk under a suspended load, cargo barriers in vehicles)  Is adequate ventilation provided to ensure a supply of clean air?  Is air filtered to remove air-borne contaminants where necessary?  Are people protected from noise? (noise levels below 85dB(A))  Is there enough light to perform tasks without eye strain or glare?  Is the working temperature comfortable?  Do workers have access to clean and hygienic toilet and eating facilities?

Moving around
 Have you made sure people cannot slip or trip when they move around? (on oil, grease, water, leads, hoses, cables)  Have appropriate fall prevention methods been implemented for all tasks that are undertaken at height? (guard rails, scaffolds, harness systems)  Can traffic and people move safely around the work site? (walkways clearly marked, barriers to separate vehicles from walkways, unobstructed vision at intersections)  Is it easy to get in and out of the workplace safely? (exits clearly marked and unobstructed)  Are stairs, ladders and platforms safe? (fixed handrails, ladders secure when in use, anti-slip treads)  Are vehicle drivers trained and aware of hazards?  Do vehicle drivers have safe schedules and are all loads secure?

Chemicals and other hazardous substances
 Is there an up-to-date list of all chemicals used? (cleaning products, paints, solvents, degreasers, petrol, inks, toner, oil, adhesives, acids, acrylics, pesticides)

 Have you obtained Material Safety Data Sheets (MSDS) for all chemicals and made these available
to workers for information?

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 Have you assessed the risk of exposure (via inhalation, skin contact, ingestion) during transport, storage and use of the chemicals?  Are containers clearly labelled?  Are chemicals and other hazardous substances stored safely? (in specific storage rooms or cabinets, separated from other reactive substances, away from ignition sources)  Are workers trained in the safe use, handling, storage and transport of chemicals they use?  Is there adequate ventilation and fume extraction?  Have you ensured that chemicals and hazardous substances cannot spill, leak or otherwise escape into the environment during storage, handling and transport?  Are gas cylinders stored upright, secure, away from heat and ignition sources, in a ventilated area?  Is monitoring and health surveillance undertaken if required?  Are chemicals and hazardous substances disposed of correctly?  Is appropriate personal protective equipment provided? (gloves, respirators)

Electricity
 Are electrical leads, plugs, sockets and switches in good condition? (not frayed or damaged)  Have you ensured there are no electrical leads lying across floors ?  Have you ensured there are no double adaptors used?  Have electrical leads and power boards been inspected and tagged as safe?  Is the location of power lines and cables checked before digging, drilling, using cranes, ladders, erecting scaffolding? (Overhead, underground, behind walls)  Are portable electrical equipment fitted with residual current devices?

Emergencies  Have you developed procedures to cover the safety of employees, visitors, customers/clients,
children and persons with disabilities who may be at your workplace in the event of an emergency?  Have those in charge or responsible for specific duties during emergencies been appointed and trained?  Are evacuation plans and emergency phone numbers on display in a prominent area?  Are exit and assembly points easy to get to?  Do exit doors open easily from the inside, including cold store room doors?

 Have all employees practiced the emergency procedures?
 Is all emergency equipment in place and functioning? (Smoke or heat detectors,

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 sprinkler systems, fire extinguishers, duress and other alarms, security screens and doors, emergency lighting, eye wash stations and showers)

First Aid
 Have all possible types of injuries been considered in assessing first aid requirements?  Are first aid supplies and trained first aid officers easily accessible to all employees?  Do you keep records of any first aid provided?

Injury Recording and Reporting  Do you keep a Register of Injuries in your workplace that is easily accessible to the workers?  Are serious injuries and dangerous occurrences reported to ACT Work Cover?
 When something goes wrong, are the causes identified and actions taken to prevent recurrence, even after a near miss or after reports of pain or strain?

Workers Compensation and Workplace Rehabilitation
 Do you have a current workers compensation policy in place with an approved insurer to cover your workers?  Are all workers aware of the steps involved for making compensation claims?

 Do you have Injury Notices available for the purposes of early notification of an injury to your
insurer?  Are claim forms made available to your workers on request, and are they lodged with your insurer within 7 days?

 Have you developed a Return to Work Program to facilitate an early and safe return to work for
injured workers receiving workers compensation?

 Are workers aware of the Return to Work Program, and is a copy displayed at your workplace?  Is a copy of the Information Summary displayed for your workers to view?
 Do you have access to an ACT approved Rehabilitation Provider?

d)

HANDLING OF DRUMS  Drums are used throughout the plant to transport and store a wide variety of solvents, solutions, and solids. They are usually 200 lts when filled, weighing between 200 to 225 kgs.  Utilize the proper hoists, carries and tilting devices when handling drums.

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 Always use grounding wires on a drum when either withdrawing or adding flammable solvents.  When opening a drum, cautiously unscrew the bung cap to release gradually any pressure, which may have developed.  Two persons are required to open a full drum. Stand on opposite sides facing the middle of the drum. Grasp both the bottom and the top, then lift one end and press down on the other, straighten your body as the drum is raised.  When lowering a drum down a steep skid, slide it end-wise rather than allowing it to roll. When rolling a drum up a skid, two persons should stand at opposite sides of the skid.  Keep your hands near the middle of a drum when rolling it. Never use your feet. Beware of catching your hand between the drum end and some hard surface.

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BASIC REACTOR ELEMENTS Reactions are carried out as batches or with continuous streams through a vessel. Flow reactors are distinguished by the degree of mixing of successive inputs. The limiting cases are: (1) with complete mixing, called an ideal continuous stirred tank reactor (CSTR), and (2) with no axial mixing, called a plug flow reactor (PFR). Real reactors deviate more or less from these ideal behaviors. Deviations may be detected with residence time distributions (RTD) obtained with the aid of tracer tests. In other cases a mechanism may be postulated and its parameters checked against test data. The commonest models are combinations of CSTRs and PFRs in series and/or parallel. Thus, a stirred tank may be assumed completely mixed in the vicinity of the impeller and in plug flow near the outlet. The combination of reactor elements is facilitated by the concept of transfer functions. By this means the Laplace transform can be found for the overall model, and the residence time distribution can be found after inversion. Finally, the chemical conversion in the model can be developed with the segregation and maximum mixed models. Simple combinations of reactor elements can be solved directly.

Fire safety and zoning
⇒ Explosive Gas Atmosphere: A mixture with air, under normal atmospheric conditions, of flammable materials in the form of gas, vapours or mist, in which, after ignition, combustion spreads through out the unconsumed mixture. ⇒ Hazardous Area:

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An area in which an explosive gas atmosphere is present or likely to be present, in quantities such as to require special precautions for the construction, installation and use of electrical apparatus. ⇒ Non Hazardous Area: An area in which an explosive gas mixture is not expected to be present in quantities such as to require special precautions for the construction, installation and use of electrical apparatus. Zones: Hazardous areas are classified in Zones based upon the frequency of appearance and the duration of an explosive gas atmosphere as follows: ♦ Zone 0 An area in which an explosive gas atmosphere is present continuously or is present for long periods. ♦ Zone 1 An area in which an explosive gas atmosphere is likely to occur in normal operating conditions. ♦ Zone 2 An area in which an explosive gas atmosphere is not likely to occur in normal operation and if does occur it will exist for a short period only. Normal Operation The situation when the plant equipment is operating within its designed parameters.  Minor releases of flammable material may be part of normal operation. For example, releases from seals which rely on wetting of fluid being pumped are considered to be minor release.  Failures (such as the breakdown of pump seals, flange gaskets or spillages caused by accidents) which involve repair or shut-down are not considered to be part of normal operation.

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Explosive Limit ♦ Lower Explosive Limit (LEL). The concentration of flammable gas, vapour or mist in air below which an explosive gas mixture will not be formed. ♦ Upper Explosive Limit (UEL) The concentration of flammable gas, vapours or mist in air above which an explosive gas mixture will not be formed. ⇒ Flammable Material Material consisting of flammable gas, vapour, liquid and or mist. ♦ Flammable gas or vapour Gas or vapours, which, when mixed with air in certain proportions, will form an explosive gas atmosphere. ♦ Flammable liquid A liquid capable of producing a flammable vapour or mist under any foreseeable operating conditions. ♦ Flammable mist Droplets of flammable liquid, dispersed in air, so as to form explosive atmosphere. ♦ Flash point The temperature at which the liquid gives so much vapour that this vapour, when mixed with air, forms an ignitable mixture and gives a momentary flash on application of a source of ignition. ♦ Boiling point The temperature of a liquid boiling at an ambient pressure (101.3kPa) ♦ Auto Ignition temperature

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The lowest temperature at which ignition occurs in a mixture of explosive gas and air without any source of ignition.

Adequate Ventilation Adequate ventilation is that which is sufficient to prevent accumulations of significant quantities of gas air mixtures in concentration over one fourth of the lower flammable limit. Adequately ventilated area could be naturally ventilated or artificially ventilated.

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PERSONAL PROTECTIVE EQUIPMENT
LEGAL REQUIREMENT: In the factories Act 1948 there are specific provisions for providing the personal protective equipment to the workers who are exposed to unsafe and unhealthy environment. The provisions of law relating to use of personal protective equipment in different operations and process are framed in such a spirit that the workers working in the operations and in the process are protected against possible hazards. It is also the intention of the law that this personal protective equipment shall be of such type and made of such materials that it can withstand to such specific hazards for which it is actually being used. NEED FOR PERSONAL PROTECTIVE EQUIPMENT: In industry it may be possible to substitute a dangerous substance with a safer substance, to isolate the process, to have automatic and mechanical handling of the substance or to have controlled ventilation of the process or to plan and arrange operation that personal protective equipment are not necessary, but sometimes it may not be possible to introduce such measure or there might be a breakdown in the plant or in the control measure. Under such circumstance it will become necessary to use personal protective equipment. It must be borne in mind that personal protective equipment does not eliminate a hazard. These devices are designed to interpose an effective barrier between a person and harmful objects, substances or radiations. REQUIREMENT OF PERSONAL PROTECTIVE EQUIPMENT: Requirement of suitable personal protective equipment can be listed as under: a) b) c) d) e) f) Nature of the hazard : Severity of the hazard : Type of contaminant : Concentration of the contaminants : Duration of work : Location of the contaminated area with respect to a source of clean air :

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g) h) i) j) k)

Expected activity of the wearer : Operating characteristic and limitations of the equipment : Reliability of the equipment : Acceptance of the wearer : Cost of the equipment :

TYPES OF PERSONAL PROTECTIVE EQUIPMENT: Personal protective equipment may be divided into two broad groups: (i) (ii) Non-respiratory protective equipment Respiratory protective equipment

Non-respiratory Protective Equipment: Personal protective equipment for various parts of the body can be divided into Five broad groups. Head Protection : Head protectors may be hard hats and caps made of aluminum, PVC fiberglass, laminated plastic or vulcanized fiber. They may be fitted with brackets for fixing welding masks, protective face screen, or a lamp. The hats and caps provided with replacement harness which provide sufficient clearance between the top of the head and shell. Splashing of liquids gases and fumes Reflected light, glare and radiant energy Foundry work, glass furnace, gas welding and cutting are welding. Handling of acids and other chemicals

Eye protectors may be safety spectacles, mono-goggles, impact goggles, welding goggles, foundry goggles, chemical goggles, gas tight goggles, face shields, welding helmets, etc. Hand and Arm Protection: 138

Protection of hands and arms becomes necessary when workers have to handle materials having sharp end, sharp edges or hot and molten metals, chemicals and corrosive substances have to be handled. The protective equipment may be gauntlet gloves, wrist glove mittens, hand pads and thumb and finger guards and sleeves. It is important not only that the various parts of arm and hand are adequately covered, but that they should be covered by a material suitable for withstanding the specific hazard involved. I. Equipment : Sleeves, Wristlets Hazard Sparks, hot materials and heat Sparks, hot materials, hot liquids flying particles cuts and abrasions. Sparks, hot materials, heat flying particles and machinery Hot liquids, moisture, acids and alkalis and dermatitis. Hot liquids moisture, acids and alkalis, electric shock and dermatitis Acids and alkalis Hot liquids

Material 1) 2) 3) 4) 5) 6) 7) Heat Resistant Chrome leather Flame proofed duck Plastic Rubber Chemical Resistant material Reflective fabric

II.

Equipment : Gloves, Mittens, Hand and finger Fuards Material Heat Resistant Chrome leather Rubber Hazard Sparks, hot materials and heat Sparks, hot materials, hot liquids, flying particles, cuts and abrasions. Hot liquids, moisture, acids and

1) 2) 3)

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4) 5) 6)

Plastic rubber coated fabric Metal mesh Cotton canvas

alkalis electric shock and dermatitis. Cuts and abrasions Cuts and abrasions Cuts and abrasions

Foot and Leg Protection : Adequate protection may have to be provided to the workers employed in certain jobs. Risk of injury may be in handling of heavy materials, etc. common foot and leg protective equipment are safety and boot, legging, foot-guards and leg guards. III. 1) 2) 3) 4) 5) 6) 7) 8) Material Heat Resistant Chrome leather Flame-proofed duck Plastic rubber Rubber Fiber metals Equipment : paints, Knee Pads, Legging Hazard Sparks, hot materials and heat Sparks, hot materials, hot liquids, flying particles, cuts and abrasions. Sparks, hot materials, heat flying particles and machinery Hot liquids, moisture, acids and alkalis. Dermatitis, hot liquids, moisture acids and alkalis, electric shock and dermatitis. Sparks flying objects, flying particles, cuts, and

abrasions and machinery. Chemical resistant Acids and alkalis Reflective fabric Hot liquids IV. Equipment : Shoes and Boots Material Steel toe caps Non-skid shoes Wooden soles Hazard Flying objects Moisture Hot materials, heat, hot liquids, moisture, acids and alkalis, slips and falls and cuts and abrasions. Sparks, hot materials, head and hot liquids. Hot liquids, moisture, acids and alkalis, electric shock and dermatitis. Explosive

1) 2) 3)

4) 5) 6)

Chrome leather Rubber Conductive rubber

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Body protection Sometimes it becomes necessary to provide special protective equipment for the body in the form of aprons, overall, jackets and complete head to toe protective suits. Nature of potential hazards degree of the hazard involved and nature of activities of the user concerned are important considerations in the selection of safety clothing. Although complete coverage of the body and leg is not needed in many cases and unnecessary safety clothing may hamper the efficiency of the user, no compromise should be made with strict safety requirement. If a user needs complete coverage, he should have it. V) Equipment : Coats, Aprons & Waist Hazard Sparks, hot materials and heat Sparks, hot materials, hot liquids, flying particles, cuts 3) Plastic and abrasions. Hot liquids, moisture, acids and alkalis, electric shock, 4) Rubber dermatitis and machinery. Hot liquids, moisture, acids and alkalis, electric shock, 5) 6) 7) Canvas Chemical resistant fabric Reflective fabric dermatitis and machinery. Flying particles, cuts and abrasions. Acids and alkalis Hot liquids

1) 2)

Material Heat Resistant Chrome leather

Respiratory Protective Equipment Atmospheric contaminants range from the relatively harmless substances to toxic dusts, fumes, smokes, mists, vapor and gases. Processes which present hazards of exposure to

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harmful substances should if possible, be closed or ventilated to eliminate or minimize the hazard. If enclosure, ventilation or other engineering means of control are not possible or become very costly to apply to the degree required to ensure absolute safety, respiratory equipment should be provided to the workers exposed to possible hazard. Even though engineering means of control are applied satisfactorily, a supply of appropriate protective equipment should be readily available for use, as there will be plant breakdown and repairs may have to be carried out in contaminated environment, respiratory protective equipment should be considered a last resort, or as stand by protection and never a substitute for effective engineering control.

Classification of Hazards : Type of hazards to which a worker is exposed is the basis of selection of the right type of respiratory protective equipment. The hazards may be classified as under: Oxygen deficiency: Atmosphere in confined spaces such as tanks holds of the ships, etc. may contain air with oxygen content much lower than the normal (21% by volume). This may be due to dilution on displacement of the air by other gases or vapors or because of loss of oxygen due to decay of organic matter, chemical reaction and natural oxidation over a long period of time. A person breathing air with oxygen content of 16% or less may exhibit symptoms ranging from increased rate of breathing, acceleration of pulse rate to unconsciousness and death. Such oxygen deficiency condition can easily be detected as the flame of a safety lamp will be extinguished in such atmosphere. The respiratory protective equipment, in such conditions, should either supply normal air or oxygen to the wearer. Listed below are some of the signs and symptoms when person at rest are exposed to air / atmosphere containing less than the normal oxygen content. Oxygen Content

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12%-14% 10%-12% 8%-10% 6%-8% 4%

Respiration deeper, pulse up, coordination poor. Respiration fast and shallow, giddiness, poor judgment, lips blue. Nausea, vomiting, unconsciousness, ashen face. Eight minutes, 100% fatal; six minutes, 50% fatal; four to five minutes, all recover with treatment. Coma in forty seconds, convulsions, respiration ceases, death

Entering a confined space whose oxygen content is less than atmospheric air should only be made under supervision and with an independent air supply.

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Gaseous Contaminants These may be toxic or inert gases. The toxic gases may produce harmful effect even if they are present in relatively low concentrations. The inert gasses produce undesirable effects primarily by displacement of oxygen. Gaseous contaminants immediately dangerous to life: The gaseous contaminants present in concentrations that would endanger life of worker breathing even for a short period of time. In other words, a gas is 'immediately dangerous to life' if it is present in certain concentration. Where it is not possible to determine the extent of concentration or the kind of gas is not known all gases should be considered as 'immediately dangerous to life'. Gaseous contaminants not immediately dangerous to life These contaminants are gases present in concentration that could be breathed by a worker for a short time without endangering his life but which may cause possible injury after a prolonged single exposure or repeated short exposure. But even after the concentration of the contaminant is known, no exact formula can be applied to determine if the contaminant is immediately dangerous to life or not.

a)

Particulate contaminants (Dusts, Fumes, Smokes, Mists, Fogs)

Majority of particulate contaminants are not immediately dangerous to life. They may be solid, liquid, or a combination of solid and liquid and may be classified into three broad groups. i) These when inhaled may pass from the lungs into the

blood stream and are then carried to the various parts of the body. The effect may be chemical irritation, systemic poisoning or allergic reactions. Common contaminants in this group are antimony, arsenic, cadmium, chromic acid and chromates, lead and manganese.

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ii)

Fibrosis - Producing dusts These dusts do not pass into the blood stream but remain in the lungs and may cause pulmonary impairment. The common examples under this group are asbestos, coal, bauxite and free silica. iii) Nuisance dusts

These may dissolve and pass directly into the blood stream or may remain in the lungs producing local systemic effects.

b)

Combination of gaseous and particulate contaminants The gases and particulate contaminants may be entirely of different substances like carbon monoxide and oxides of nitrogen produced by blasting and the dust from the blasted material or they may be some substances in liquid and vapor form like volatile liquids.

Types of respiratory protective equipment Airline Respirator Airline respirator consists of a face-piece (half or full mask or a loose fitting helmet and hood) to which air is supplied through a small diameter hose. It may be continuous flow type or a demand type.

a)

In a continuous flow type, air is supplied continuously to the

face piece helmet or hood. Exhaled air and the excess air entering the facepiece escapes to the atmosphere. Air supplied should be at least 110 liters of air per minutes to enter the face and at least 170 liters per minutes to enter the helmet or hood.

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Airline respirators provide protection so long as the air supply is maintained but the wearer's travel is restricted by length of the air supply hose. Care should be taken to ensure that the air supply is without oil or water mist and dust particles from the supply line. b) In a demand type respirator, air is supplied to a face-piece

when the wearer inhales and the rate are governed by his volume rate of breathing. Air from an air compressor compressed from a cylinder air is supplied to the face piece through a demand valve which is actuated by the slight negative pressure created when the wearer inhales. On exhalation the demand valve closes and exhaled air escapes to the surrounding atmosphere through exhalation valve. Helmets or hoods are not used with demand type respirator. 1) Suction Hose Mask

It consists of a full face piece connected to a large diameter flexible hose. The worker draws in air by his own breathing effort, the hose is attached to the wearer's body by a suitable safety harness with safety line and the air inlet end of the hose if provided with a filter to arrest particulate matter. Air can be drawn in by respiratory effort of the wearer unto 30ft. length of the hose. 2) Pressure Hose Mask

This hose mask is similar to suction hose mask except that, air is forced through a large diameter hose by a hand or meter - operated blower. The blower is to be operated continuously while the mask is in use. 3) Self-contained compressed air or oxygen breathing

apparatus This is an equipment by means of which wearer obtains clean air or oxygen form compressed air or oxygen cylinder which is an integral part of the apparatus.

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In a demand type self-contained breathing apparatus, air enters only when the wearer inhales and the quality of air or oxygen admitted is governed by his breathing. The wearer's exhaled air escapes to the surrounding atmosphere. In compressed oxygen cylinder recirculation type breathing apparatus, high pressure oxygen from the cylinder passes through a pressure reducing and regulating valve into a breathing bag. The wearer inhales this oxygen through a one-way breathing valve and his breath passes into a canister containing chemicals to absorb exhaled carbon dioxide and moisture and then through a cooler into the same breathing bag. Oxygen enters the breathing bag from the supply cylinder only when the volume of gas in the bag has decreased sufficiently to allow the supply valve to open. From respiratory point of view, self-contained breathing apparatus has no limitations as to the concentration of the gas or deficiency in the surrounding atmosphere but other factors may limit the time that water can remain in a contaminated atmosphere. Many gases are very irritating to the skin and many can be absorbed in dangerous amounts through the unbroken skin. Oxygen regarding re circulating type self : In this apparatus moisture content from the wearer's exhaled breath reacts with granular chemical in a canister to liberate oxygen. Also the exhaled carbon dioxide is absorbed by the chemicals in the canister. This oxygen enters the breathing bag from which the wearer inhales through a corrugated breathing tube connecting the bag to the face-piece. Air purifying respirator 1) Canister gas mask

This consists of a canister, containing appropriate chemical, a full face-piece and body harness to hold the canister in place on the body of the wearer. Air is drawn through the canister by the wearer and during its passing through the

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canister the contaminant present in the incoming air is absorbed in the chemical. The canisters are designed for specific gases and it is very important that the appropriate type is used. The canister gas mask can only be used in atmosphere not deficient in oxygen and not containing more than 2% by volume of most toxic gases. Also the life of the canister will depend upon the type of canister, the concentration of gas and the activity of the wearer. Like canister gas mask, chemical cartridge respirator provides respiratory protection for a period that depends on the type of cartridge used the concentration of the gas or vapor and the wearer's activity. It is recommended for low concentration gases and vapors (maximum of 0.1% of organic vapor). 2) Self-Rescue type respirator

This is designed to provide the greatest possible respiratory protection consistent with the practicability of carrying the device at all times so that it is always available for use during escape. It consists of a filter element a mouth piece, a nose clip and means of carrying conveniently on the body. The filter elements are similar to chemical cartridge. The extent of protection afforded is between that provided by canister gas mask and that provided by a chemical cartridge respirator. 3) Mechanical filter respirators

These remove particulate matter form the air which passes through a filter. These filters may be of the single use or reusable type. If these respirators are used in heavy concentration of particulate matter, the filter will be clogged with dust particles too quickly and they may have to be replaced every now and then. Micro filters are special filters designated to arrest ultra microscope size of dust particles and those are used where extremely fine dusts are encountered.

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Accident investigation report

Accident/Incident/Near Miss Investigation form Incident Information Type of Time Incident Details of Injured person Name Age Phone Supervisor Length of employment at Job Worker Casual Employee Chemical Other (Specify) Injured part of Inhalation body Address

Date

Shift

Department

Job Title Length of Employment at company Employee Classification Staff Nature of Dislocation Injury (tick

appropriate) Strain sprain Internal First Aid Fracture Burns Hospitalization Cut Scratches Bruising Name and Address of treatment hospital Damaged Property Property, Equipment or material Damaged

Description of damage

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Incident Description Describe what happens in specific steps (can be in local language):

Root Cause Analysis Unsafe Acts Improper work techniques Safety rule violation Selection of Improper tool Operating with out authority Not wearing PPEs Operating at improper speed Unauthorized entry Working with out work permits and working on electrically charged items Horse play Drug/alcohol Use Improper loading Improper placement of materials Improper lifting Others (Specify

Unsafe Conditions Poor design of work station Congested work place Poor lighting Poor ventilation Hazardous substances Fire and explosion hazard Unguarded equipments Working at hot surfaces

Other failures Inadequate instructions In sufficient worker training Improper maintenance Lack of written procedures and policies Non availability of PPE In sufficient supervisor training Safety rules not enforced Lack of supervision

Poor house keeping Excessive noise Inadequate fall protection Slippery floor conditions Working at electrically charged machines Others (Specify)

Un realistic scheduling Poor process design Inadequate equipment Inadequate hiring practices Hazards not identified Others (Specify)

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Incident Analysis (Using the above root cause analyses, explain the causes of the incident in as much detail as possible) (can be in local language):

Preventive Actions Sl.No Actions that will be taken to avoid recurrence

Responsibility

Target Date

Status

Name

Investigation Team Position

Signature/date

Color coding :
1.0 Identification of line and equipment:

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Identification of line and equipment is most desirable and useful for safety purpose. Lack of uniformity in identification of pipeline and equipment in industrial installations has often been responsible for mal-operation and major hazard which can lead to an accident. Uniformity in identification promotes better safety and prevents chances of error in the handling of material inside the pipeline, equipments. 2.0 Method of Identification: Identification of the particular contents of the pipelines is achieved by having suitable color bands on the ground color. Fixing tags or lettering as a mode of identification is also recommended for chemical factory, as this will reduce the possibility of mistakes in identification. Tag / lettering may include the contents by name, chemical formula or by simple and commonly understood abbreviations.

As per IS 2379:1990 color code defined at DNL for proper identifications of various utilities, Toxic / corrosive / flammable chemical transferring lines as under;

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Sr. No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 22 21

Pipeline of chemical Cooling Water Boiler Feed Water Soft Water Chilled water Fire Water Steam HP Steam LP Compressed Air above 5 kg/ cm2 Plant Air Instrument Air Vacuum Nitrogen Ammonia Chlorine Sulfur Dioxide Benzene Methanol Hydrochloric Acid Sulphuric Acid Nitric Acid Sodium Hydroxide Solution

Ground Color
See Green See Green See Green See Green Fire Red Aluminum Cladding Aluminum Cladding Sky Blue Sky Blue Sky Blue White Canary Yellow Canary Yellow Canary Yellow Canary Yellow Dark Admiralty Grey Dark Admiralty Grey Dark Violet Dark Violet Dark Violet Smoke Gray

1st color band French Blue Gulf Red Light Grey Black Crimson Red French Blue Canary Yellow Signal Red Silver Grey French Blue -Black Dark Violet Dark Violet Dark Violet Canary Yellow Deep Buff Signal Red Brilliant Green French Blue Light Orange

2nd color band --Signal Red Canary Yellow ---------Light Orange Golden Brown --Light Orange Light Orange Light Orange --

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Management of change
Assessment of Change

Degree of Hazard
Yes No Sl. No. 1. Does the change introduce or affect a source of chemical, mechanical, thermal, or electrical energy? (EG: Installation/modification of 100 hp motor, increase in line pressure, etc) 2 Does the change result in any increase in the inventory of toxic, flammable, or reactive materials? If so, what is the maximum anticipated site inventory? ______________ Kgs. 3 4. . Does the change introduce a new chemical? Does the change introduce a chemical which is designated or carcinogenic?

Hazard rule:
Degree of hazard

Two or more “YES” answers constitutes a high degree of hazard.
 High  Low

Significance of Proposed Change:

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Yes No Sl. No. 1. Could the change take the process or system outside previous limits of normal operation (outside the well understood and documented ”safe operating envelope“) during steady state or transient conditions ? 2. Does the change alter the processing sequence (SOP) and as a result introduce a hazard ? 3. Does the change alter , affect, or bypass a safety device or critical control system or component? 4. Does the change necessitate significant or unique training for operators or technical personnel?

Significance Rule: Two or more “YES” answers constitutes a high significance of change Significance of change  High  Low

Risk Level
Significance of proposed Change Low High Level 1 Level 2 Level 3 Level 4

Degree of Hazard

Low High

Required task according to the risk level
MOC Form 2 DNL_ HAZOP PSSR Approval of plant Approval Chief

of site Mgr. Executive-

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Level 1 Level 2 Level 3 Level 4

   

 

 

Mgr.    

Technical.    

 

Management of change Form
1.Safety, Health and Environmental Review
Y Process safety review (DNL HAZOP) Pre-startup Safety Review(PSSR) Occupational Risk Assessment Environmental Assessment
Complete=Action items with immediate impact are

7.Implementation of Required Task
Due date Date Completed Date/Signature

N

Person in charge

2. SOP/Procedure/Manual Revised
Y Start up/Shut down/Emergency Stop Normal operation Maintenance Emergency response Others*1( ) N Person in charge Due date

resolved prior to start up and the plan is in place to address long range items

Date Completed

Date/Signature

*1 administration etc 3. Briefing and Training

Complete= Revised procedures issued . Any obsolete procedure discarded.

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Y Plant operator Maintenance person Contractor Others( )

N

Person in charge

Due date

Date Completed

Date/Signature

Complete = All specified personnel have received and understood training. Responsibility for any change to permanent training materials.

4.Process Safety Information(PSI) revised Y N Person in Charge P&ID PFD Electrical system documentation Relief system documentation MSDS Documented Operating Limits Safety Devices Others( ) Person in Charge PCB Due date Date Completed Date/Signature Due date Date Completed Date/Signature

5.Application to Authorities Y N

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Factory inspectors CCOE Others( )

6.Approval of the change
This change has met the appropriate review requirements and has been approved ______________________________ Date/Signature(plant Manager) ________________________________ Date/ Signature(Safety Manager)

8. Confirmation of task completion. All required tasks have been completed appropriately.

______________________________ Date /Signature (Site Manager)

_________________________________ Date/ Signature(Chief executive-Technical) Date /Signature (MOC Coordinator)

After the approval of concerned managers, this form should be kept by MOC coordinator. MOC coordinator should manage the progress of required tasks. Date /signature (site Manager) After the confirmation of MOC Coordinator this form should be kept with other related document by originating department. Date/Signature (plant Manager)

Training and other safety & health measures
1. Training of first aid fire fighting and accident prevention is imparted twice every year to all the employees, by the officers of fire and safety section. Sufficient numbers of employees have also been trained by St. John Ambulance Association on ‘First aid to the injured’. 2. case of major disaster. 3. Emergency instructions are displayed at required places indicating actions to be taken in case of any leaks of Ammonia, Chlorine and Naphtha. Hoarding of hidden hazards are also displayed in different plants along with the control measures to be adopted while working there. Twice in a year, Fire and safety section exercised Disaster ONSITE Mock Drill with information to all Local authorities, for proper readiness in

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4.

Wind socks are provided in Ammonia Plant, Ammonia Storage and handling area, Chorine handling area and other strategic locations to indicate wind direction in case of any toxic gas leak.

5.

Portable oxygen meters and Explosive meters/Combustible Gas Indicators are also available in fire and safety section for checking the area or vessel, before entry and job to be carried out.

6. 7. 8.

Periodic medical examination is being done for the employees Proper hygiene and decontamination facilities have been provided and being done regularly By putting the objectives and targets in OHSAS-18001like various trainings on Fire & Safety ,environment and health matters, periodic health check of the employees, training of Truck drivers and transporters and Importantly to contract and casual labour. and then follow up is being done rigorously to meet the objectives

9. 10. 11.

All chemicals MSDS (Material Safety Data Sheet) are kept at easily available places to know about the properties and other values. Each chemical antidotes are also kept available in the hospital and at various places. In order to create sense of safety consciousness safety section organises, various competitions every year like safety essay, slogan, debate and quiz competitions for regular employees and safety drawing competition for their children. Prizes are also given to the winners for motivation.

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Do’s and Don’t for centrifuges
Centrifuges are dangerous unless operated correctly and properly maintained. An accident can have destructive effects, not only to the user but also to the laboratory. The hazards are: Physical contact with the rotating head; Mechanical breakage of rotors caused by overloading or corrosion; and Severe vibration caused by an unbalanced rotor. Careless balancing of the load can cause the heads of even bench centrifuges to disintegrate during use. A further hazard, the formation of aerosols, arises when microbiological samples are centrifuged, where this is a potential hazard, sealed centrifuge buckets are necessary. General Precautions with Centrifuges The manufacturer's operating instructions should be followed, particularly regarding:  Balancing tolerances;  Operating speeds for different rotors; and  Loads and rotor maintenance. High speed centrifuges require careful supervision, and prior training of users. Records of use must be kept for each rotor so that it can be de-rated when necessary. Centrifuges should be inspected and serviced at regular intervals by the manufacturer, or a competent engineer Operation

The centrifuge lid must be closed whenever the rotor is in motion, and should be interlocked so that it cannot be opened when the rotor is in motion. The centers of gravity of paired tubes should be equidistant from the centre of rotation e.g. it is not acceptable to counterbalance 10 g of water against 10 g of mercury, or a solution with a density gradient against a homogeneous solution. Certain types of apparatus e.g. zonal rotors require extreme care during assembly. In all cases, the manufacturer's instructions must be followed carefully.

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The speed should be increase slowly. If any abnormal symptoms develop, the centrifuge should be stopped at once. The maximum speed for the rotor should not be exceeded. The centrifuge should be stopped by returning the speed control to zero and not by switching off the mains supply. It is very dangerous to stop the rotor by friction applied direct by hand or indirectly via a bung or other implement. A warning notice should be affixed to each machine to the effect that the lid of the centrifuge must not be opened until the head has stopped rotating.

Corrosion
Since corrosion is the main cause of rotor failure, it is crucial that the manufacturer's instructions for the care and maintenance of rotors are followed. Liquid spilt in the centrifuge should be removed immediately and the use of water in the buckets for balancing is to be avoided. Rotors and accessories should be cleaned regularly and inspect for signs of corrosion.

Definitions
• Laboratory centrifuge: An apparatus used in the laboratory for separating substances of different density or particle size, when suspended in a fluid, by spinning them about an axis in a suitable container. • Rotor: Primary component of a centrifuge which holds the material to be subjected to centrifugal force (in some form of tube/container) and which is rotated by the drive system.

Hazards
    Mechanical failure of rotating parts (often violent). Contact with rotating parts. Sample leaks causing aerosols, stress corrosion, contamination. Sample imbalance causing machine movement / walking (or stress failure of Fire or explosion.

component parts). 

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Health (contact with contaminated components / vapours).

Operation of centrifuge
  Only suitably trained persons may operate a centrifuge. Where necessary, the machine log book must be filled in (a log book must be kept Before use the rotor, its lid and seals must be examined for cleanliness and damage (a

for ultra centrifuge rotors as the hours run determine the life of the rotor).  build-up of chemicals from spillages may cause a tube to jam in the rotor or cause corrosion that could lead to a rotor failure). Damaged rotors must not be used and should be reported to the Supervisor, dirty rotors must be cleaned by the approved method. (see rotor care).  Never fill centrifuge tubes above the maximum recommended by the manufacturer. Never exceed the maximum stated speed for any rotor. Derate the rotor speed whenever:The rotor speed/temp combination exceeds the solubility of the gradient The compartment load exceeds the maximum specified. (see manufacturers catalogue).   o o

material and causes it to precipitate.

Failure to reduce rotor speed under these conditions can cause rotor failure.  Balance the rotor to within the limits specified (take care that materials of similar Do not operate the centrifuge without the appropriate rotor cover securely fitted and Check compatibility of tube material to solvent medium.(some solvents may cause Use only correctly fitting tubes. Clean up spillages immediately. (use appropriate PPE if necessary). Do not use chemicals that are explosive, highly flammable or have vigorous chemical

densities are in opposite positions of the rotor).  its seals in place.  the tubes to swell or crack in the rotor)   

interaction without observing the appropriate safety precautions to minimise risk of vapour build-up.

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Never attempt to open the lid of a centrifuge or slow the rotor by hand or open the lid Only authorised and suitably trained persons may service or repair a centrifuge,

while rotor is in motion as serious injuries may be incurred.  report all faults promptly, do not attempt repairs yourself. Do not use the centrifuge until the fault has been inspected or repaired.

Rotor Care
 Stress corrosion is thought to be initiated by certain combinations of stress and chemical reaction. If the rotor is not kept clean and chemicals remain on the rotor, corrosion will result. Also, any moisture left for an extended time can initiate corrosion. It is important that the rotor is left clean and dry. (Wash with mild detergent and warm water, careful use of a nylon bottle brush when necessary). Dry the rotor thoroughly and store upside down with the cover and tubes removed.   Do not autoclave at temperatures above 100°C. Do not expose aluminum rotor components to strong acids or bases, alkaline lab

detergents or salts (chlorides) of heavy metals (e.g. caesium, lead, silver or mercury.) Use of these can initiate corrosion.

Pre-run safety checks
  Make sure each tube compartment is clean and corrosion free. Make sure the rotor itself is clean, corrosion and crack free and that there are no Check centrifuge chamber, drive spindle and tapered mounting surface of the rotor Wipe drive surfaces prior to installing the rotor. If the temperature of the chamber is below room temperature, pre-cool the rotor to the

scratches or burrs around its rim.  are clean and free of scratches or burrs.  

lower temperature before securing the rotor (this will minimise the chance of it seizing to the tapered spindle).  Make sure that any rotor lid securing device and any rotor to spindle securing device is fully secured before starting the machine.

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Training
All new users of centrifuges must be trained by an appointed instructor (who may be an appropriately qualified or experienced member of staff) before attempting to use a centrifuge. It is strongly recommended that the film "Principles and Practices of Centrifugation" should be watched.

Level of Risk Remaining
Centrifuges are potentially lethal pieces of equipment and care and vigilance need to be exercised at all times. Following the procedures outlined here will reduce risk to a low level. Safety Audit by external agency There is a Safety Audit by external agency which once in a year conduct thorough audit of entire complex, in line with guidelines mentioned in IS 14489: 1998, and submit recommendations for improvement. Internal Safety Audit There are Internal Safety Audits by core group members of ISO-9001, ISO-14001 & OHSAS-18001 covering the plant area, workshops and stores quarterly. Each core group members visit their allotted other than their working area quarterly in a year and give recommendations for improvement of safety standards and compliances of other sections according to above ISO standards. These recommendations are circulated to all concerned department for implementation. Responsibility of monitoring implementation of recommendations of different committees is that of Safety department.

Motivation for Safety
For motivating safety, DNL unit management has introduced following schemes for enhancing safety consciousness of employees: 1) Safety slogan competition. 2) Safety essay competitions 164

3) Safety films screening 4) Safety suggestion schemes 5) Safety debate competition 6) Safety drawing competition among employees and their children 7) Safety quiz competition. 8) Marathon run four times a year to increase awareness on health and safety. 9) Conducting various training programs on health and safety topics. 10) Publishing informative articles in each issue of in-house magazine

House keeping committee
There is House keeping committee constituted by unit head. This committee is chaired by any Senior Management level employee and constituted of equal members from officers and workers of different plant of mechanical and production personnel. This committee visits each plant quarterly with one surprise visit in a year and allocated marks on their good house keeping. On that basis of these marks, plants have been declared as Winner & Runner in Good house Keeping in two groups during Safety Week celebration Closing Ceremony. This competition made DNL unit as one of the best clean and green plant among chemical industry.

Safety Poster
To arouse Safety consciousness among the employees different posters and banners related to safety are displayed at relevant locations in the factory. These related to safety are rotated and changed from time to time to educate all the employees about the followings: 1) About home safety 2) About road safety 3) About working on machines and guarding 4) About working with dangerous chemicals 5) About working on heights 6) About electrical safety

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7) About use of LPG 8) About static electricity 9) About Fire 10) About Noise pollution 11) About Air / Dust pollution 12) About eye and head safety 13) About toxic substances

Safety Contests
Following safety contests are arranged to motivate the employees and their family members towards safety: 1.Good house keeping competition 2.Safety slogan 3.Safety essay 4.Safety quiz 5.Safety debate&Safety drawing In all the above competitions, attractive prizes are given to the winners, and to the wining team (Good house keeping) a shield is given on rotation basis. Safety Week At DNL unit, Safety Week is celebrated every year with great enthusiasm and the function is started from 4th March unto 10th march and prizes are distributed to the winners of the various safety competitions which are organized during that week. Safety Articles In each issue of in-house magazine “UJALA” informative articles are published for enhancing safety awareness of all employees as well as their family members.The papers which were presented by Safety staff got several awards in the various forums Safety Calendars

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Safety Calendars received from National Safety Council, Bombay having 07 pages of different safety pictures is distributed for putting on the wall at conspicuous places in offices, canteen, and control rooms of the plant for educating employees on safety aspects. Celebration of National Safety Day Every year on 4th March National Safety Day is celebrated. This is accompanied with different activities in that week as mentioned below in the detailed report Safety Inspection and Audit Programme Routine inspections of the Safety equipments are carried out by the Safety department. Internal safety audit is carried out twice a year. The recommendations of internal audits are implemented. Third parties having required expertise, are also commissioned, to conduct safety audit. The recommendations made, are implemented to the extent practicable.

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Critical equipments and kettles
The critical equipments in safety point of view and the basic functions of the equipments are given below Sl.No 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. Equipment Rector Centrifuge Tray Drier Fluidized bed drier Receivers Condensers Boilers Cooling towers Vapour absorption machine (VAM) Nitrogen Plant Nutch filters Carbon filters Millers Pelletisers Granulator Autoclave Basis function of equipment To carry out the reactions To carry out filtration For Drying of material For drying of materials Temporary storage of material For cooling of hot gases generated for reaction process For steam For cooling For chilling Nitrogen gas for inertisation For filtration For filtration of final products For milling For making pellets For making granules To carryout pressure reactions

Unloading of mobile tankers
168



Check the level in the storage tank to accommodate the quantity of the mobile tanker.

  

If, the unloading is done from mobile tanker to drums, avoid PVC / HDPE drums. Ensure that the drums are cleaned properly. Use conductive hoses with control valves and should have adequate length to reach the bottom of the drum (to avoid splash filling).



Connect the spark arrestor to the mobile tanker exhaust while entering the factory premises.



After parking in the correct position, turn off the mobile tanker engine and remove the ignition key and provide stoppers to the vehicle tyres

 

.Provide earthing to the mobile tanker body and connect it directly to the earth pit. Connect only conductive hoses between the mobile tanker & the FLP motor and between the FLP motor & the storage tank to be loaded.

 

Ensure that all the flanges and motor shaft seal should be leak proof. Connect crocodile earth continuity bonding wires between the mobile tanker and to the suction flange of the pump & from delivery flange to the storage tank. All the flanges in the pipeline transferring the solvent should be provided with bonding (jumpers).



The dip-rods used for measuring the level should be earthed properly. Do not check the level frequently with high speeds.



Workers should wear adequate/suitable PPEs while handling the chemicals / solvents.

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Hydrogenation Hydrogenation is the addition of H2 to a multiple bond (C=C, C=C, C=O, C=N, C=N, N=O, N=N, N=N, etc) to reduce it to a lower bond order. The most common and simple type of hydrogenation is the reduction of a C=C double bond to a saturated alkane: Reactor safety aspects in Handling of heavy metal Reactor safety aspects in Handling of explosives Reduction Reactor safety aspects in Handling of toxic gases Storage of chemicals (compatibility charts) Emergency Facilities: Assembly points Refuge rooms Emergency Control Centre Location of wind socks Existing Emergency Communication facility Mutual Aid List of hospitals providing medical assistance Fire Emergency Facilities and Fire Crew: Fire hydrant system Fire Extinguishers Spray System Fire Pump Details Fire hydrant points Reservoir capacity Capacity of foam Fire tenders Number of fire crew per shift Foam capacity

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PPE s  The need for the PPE in the work environment is identified by EHS Department and the Department concerned .  After identification of the need the requirement of PPE is informed to the Stores

Department.  Stores department will check the availability of PPE in the stores and will raise the

Purchase requisition if needed.  same .   All the employees will be issued PPEs depending on their nature of work. The Incharges of the respective departments should ensure that the workers are The EHS department will inspect the PPE available in the stores and will certify the

wearing adequate PPEs At a minimum, each employee using PPE must know:   When PPE is necessary What PPE is necessary and which PPE has been selected for each process the

employee operates      How to properly put on, take off, adjust and wear PPE The limitations of the PPE How to determine if PPE is no longer effective or is damaged How to get replacement PPE How to properly care for, maintain, store, and dispose of PPE

After employees have been trained, periodic assessment of the process/equipment should be conducted to ensure that the PPE is adequate and training is appropriate. List of safety provisions Safety aspects in pressure vessels

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Safety aspects in exothermic reactions FACETS OF SAFETY & HEALTH IN A CHEMICAL INDUSTRY Risk of accidents and / or harmful exposures : areas of concern ii) iii) iv) v) vi) vii) viii) ix) x) xi) xii) xiii) 1. 2. 3. 4. 5. 6. 7. 8. 9. Dangerous Materials Hazards of Pressure Vessels Hazardous Chemical Reactions Hazardous of Unit Operations Flammable Gases, Vapours And Dust Hazards Health Hazards Hazards due to corrosion Entry in To Confined Spaces Working with Pipelines Plant Alteration and modification Sampling and Gauging Hazards due to Instrument Failures. Dangerous Materials Explosives Gases Inflammable Liquids Inflammable Solids Oxidising substances Toxic and Infectious substances Radio Active Substances Corrosive Substances Miscellaneous Dangerous Substances

Hazards Of Pressure Vessels 1. 2. Leakage or Bursting of Pressure Vessels Design defects

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3. 4. 5. 6. 7. 8. 9.

Failure of Relief Systems Lack of hydraulic testing. Lack of Proper Instrumentation or Instrumentation Failure Lack of N.D.Tests Corrosion of Vessels. Lack of routine inspections Attempt of Pneumatic testing

Hazardous Chemical Reactions Understanding about the behaviors of reactions and adopting precautionary and emergency Hazards of Unit operations Understanding the hazards inherent in each unit operation and adopting precautionary and emergency measures. examples 2 Heat Transfer Size Reduction Surface Fouling & Leakage, Miscalculation in scaling, Mixing of fluids etc. Dust Explosions, Dust release, etc. Flammable Gases, Vapours And Dust Hazards  Identification of potential areas, where possibility of flammable mixture are possible.  Efforts to avoid hazardous mixtures, by inert gas purging and other methods.  Declaring hazard zones and providing flame proof electrical fittings and equipments.  Providing Explosion Vents in spaces with possibility of air-vapour mixtures.  Explosive meter testing.  Providing adequate fire control devices.  Providing arrangements to avoid static sparks. Etc. Health Hazards  Identification of potential health hazards.  Assessment of levels of physical and chemical health hazards.

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 Control of hazards by various techniques  Adequate awareness among the workers.  Periodic medical examination of the workers.  Personal protection for occasional exposures.  Proper hygiene and decontamination facilities. etc. Hazards Due To Corrosion  Weakening and falling of structures and sheds.  Falling of workers from height due to breaking of raised platforms, hand rails, toe boards, stairs and ladders.  Spills and toxic releases from pipelines due to corrosion.  Leakages and bursting of vessels due to corrosion.  Corrosion monitoring and control.  Testing and inspection of vessels and structures to ensure safety Hazards of Entry into Confined Spaces 1. Oxygen Deficiency 2. Toxic Contamination 3. Flammable Environment 4. Possibility of Electrocutions through electric equipments 5. Possibility of Toxic gas generation during the work 6. Lack of Ventilation 7. Difficulty in welfare monitoring 8. Failure to escape on emergency 9.Combustible Substances Safety While Entry into Confined Spaces  Thorough cleaning and purging before hot work.  Safety belt with one end outside.  Life line to monitor welfare.  On going ventilation.  A person to watch the welfare.

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 Low voltage electric appliances.  Self contained breathing apparatus.  Environmental monitoring for oxygen, toxic gases and flammable gases before entry.  Pipeline isolation before entry  Electric isolation before entry.  Proper ladder for entry. Safety in Use of Pipelines  Hazards due to inadequate Identification of Pipelines.  Hazards due to leakages and bursting of pipelines.  Hazards due to collision of vehicles with pipelines.  Hazards due to improper materials of construction of pipelines.  Hazards while breaking of pipelines.

SAFETY MANAGEMENT SYSTEM
There exists a well organized safety management system at DNL unit with well defined “Safety, Health & Environment Policy ”. Besides DNL has well defined Quality policy (ISO-9001), Environmental policy (ISO-14001) & Occupational

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Health and Safety policy (ISO-18001). DNL has all three systems of above mentioned topics which were certified by external agencies of international repute. The brief description of activities of safety management system is as follows:Safety Committees At DNL unit, there are following safety committees who meet regularly to discuss safety problems. These are – Central Safety Committee There is a central safety committee. The Joint General Manager (Production) chairs meetings of central Safety Committee, which meets once every quarter. Manager (EHS) is the secretary. This central Safety Committee meets with an agenda. Minutes of the meetings are drawn and circulated to all members. Departments responsible for implementation of various recommendations of this committee are decided in meeting itself. This committee mainly talks on procedural matters of safety and reviews overall Safety Management System. Plant Level Safety Committees There are 7 such committees’ viz. Ammonia-1 &2, Urea-1 &2, Power Plant, offsite and Bagging Plant. These committees are headed by the concerned Department Incharge and include equal participation of officers, workers from plants maintenance, production. It deals with plant safety problems and follows up to identify accidents causes and implementation of remedial measures. Safety Audit by external agency There is a Safety Audit by external agency which once in a year conduct thorough audit of entire complex, in line with guidelines mentioned in IS 14489: 1998, and submit recommendations for improvement. Internal Safety Audit There are Internal Safety Audits by core group members of ISO-9001, ISO-14001 & OHSAS-18001 covering the plant area, workshops and stores quarterly. Each core group members visit their allotted other than their working area quarterly in a year and give recommendations for improvement of safety standards and compliances of

176

other sections according to above ISO standards. These recommendations are circulated to all concerned department for implementation. Responsibility of monitoring implementation of recommendations of different committees is that of Safety department. Motivation for Safety For motivating safety, DNL unit management has introduced following schemes for enhancing safety consciousness of employees: 1) Safety slogan competition. 2) Safety essay competitions 3) Safety films screening 4) Safety suggestion schemes 5) Safety debate competition 6) Safety drawing competition among employees and their children 7) Safety quiz competition. 8)Marathon run four times a year to increase awareness on health and safety. 9) Conducting various training programs on health and safety topics. 10) Publishing informative articles in each issue of in-house magazine (vi) House keeping committee There is House keeping committee constituted by unit head. This committee is chaired by any Senior Management level employee and constituted of equal members from officers and workers of different plant of mechanical and production personnel. This committee visit each plants quarterly with one surprise visit in a year and allocated marks on their good house keeping. On that basis of these marks, plants has been declared as Winner & Runner in Good house Keeping in two groups during Safety Week celebration Closing Ceremony. This competition made DNL HSD unit as one of the best clean and green plant among fertilizer industry.

177

Safety Poster To arouse Safety consciousness among the employees different posters and banners related to safety are displayed at relevant locations in the factory. These related to safety are rotated and changed from time to time to educate all the employees about the followings: 1) About home safety 2) About road safety 3) About working on machines and guarding 4) About working with dangerous chemicals 5) About working on heights 6) About electrical safety 7) About use of LPG 8) About static electricity 9) About Fire 10) About Noise pollution 11) About Air / Dust pollution 12) About eye and head safety 13) About toxic substances

Safety Contests
Following safety contests are arranged to motivate the employees and their family members towards safety: 1. Good house keeping competition 2. Safety slogan 3. Safety essay 4. Safety quiz 5. Safety debate&Safety drawing In all the above competitions, attractive prizes are given to the winners, and to the wining team (Good house keeping) a shield is given on rotation basis. (ix) Safety Week

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At DNL HSD unit, Safety Week is celebrated every year with great enthusiasm and the function is started from 4th March unto 10th march and prizes are distributed to the winners of the various safety competitions which are organized during that week. (xi) Safety Articles In each issue of in-house magazine “informative articles are published for enhancing safety awareness of all employees as well as their family members. The papers which were presented by Safety staff got several awards in the various forums NSC Safety Calendars Safety Calendars received from National Safety Council, Bombay having 07 pages of different safety pictures are distributed for putting on the wall at conspicuous places in offices, canteen, control rooms of the plant for educating employees on safety aspects. Celebration of National Safety Day Every year on 4th March National Safety Day is celebrated. This is accompanied with different activities in that week as mentioned below in the detailed report Work Permit System In this Plant the Safety Work Permit system covers general work permit, Hot work and Vessel entry and a separate permit form is for Excavation work, Work at height & Work inside drains. For major jobs including Hot jobs and Vessel entry, permit is counter signed by Plant Manager as well as officer of EHS Department. The Safety department personnel countercheck each permit issued as well as job sites, to ensure safety.

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Validity of the permit is for the duration of shift (8hrs) in which it is issued. However its validity can be got extended shift wise. The total validity of work permit is for 24 Hrs. (xv) Safety Inspection and Audit Programme Routine inspections of the Safety equipments are carried out by the Safety department. Internal safety audit is carried out twice a year. The recommendations of internal audits are implemented. Third parties having required expertise, are also commissioned, to conduct safety audit. The recommendations made, are implemented to the extent practicable

180

Incident/ Accident Investigation And Reporting We have a written accident investigation procedure. This investigation procedure is included in safety manual, which has been issued to all employees. The company has adopted the policy that all incidents and accidents should be reported and investigated. For reporting accidents there is a standard format. Whenever an accident takes place, the initiation of the format is done by the Shift-incharge of the particular area. Logging is done. The Safety department investigates minor accidents and the major ones by suitably constituted committees, "Near-miss" cases are also investigated, and actions are taken to prevent recurrence. All accident/ Near-miss cases are discussed in Central Safety Committee Meetings. Recommendations of Safety Committee are percolated down to the shop floor and ensures their implementations. Disaster Prevention Action Plan A detailed Disaster Prevention Action Plant along with duties of all the Key persons has been prepared and distributed to all concerned. It is printed in flip chart booklet form and a copy of it has been displayed at all the Control Rooms for ready reference. It also contains all important phone numbers of DNL officials as well as of all the external agencies including Government officials. MAINTENANCE AND INSPECTION SCHEDULES: Daily inspection schedule is there to check the various types of compressors, pumps, fans, blowers & turbines and to monitor the vibration levels. If any abnormality found the corrective action by both production and maintenance people will be initiated at the utmost priority.

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Compliance of Statutory Regulations related to Factory Act  Hydro test of Boilers  All Pressure Vessels testing and records maintained in Form-9.  Witnessing load testing of all lifting tools and tackles -yearly and maintenance of records by mech. maint. Turnaround Activities  Ultrasonic thickness measurement of selected High pressure and Vessels for assessment of corrosion / Erosion.  Radiography of high pressure critical weld joints  Ultrasonic testing of high Pressure weld joints and thick ness of storage tanks  Internal Visual Inspection, D.P. testing & thickness measurement of Static Equipments.  Hydraulic and pneumatic testing of pressure vessels, heat exchangers and piping are being carried out by maintenance dept. after maintenance activities as per requirement.  Inspection of heat exchangers  Welder qualification test  Magnetic Particle Testing for detecting sub-surface defects. Other Need Based Activities  RPM measurement of Rotary machines  In-Situ Balancing as well as balancing on hard bearing dynamic balancing machine  Vibration measurement / analysis  Sound level measurement  Thickness measurement by ultrasonic thickness meter  Skin temperature measurement as per requirement 182

 Thermal insulation survey of pipe lines Plant Alterations and Modifications Alteration in plant, equipment, component, process, operating procedure, etc. due to some difficulty. Followed by failure in some unforeseen aspect of the system.   If any alteration is inevitable, Design intention of each and every component of the system should be well Refer the matter to the designers. Carry out HAZOP study by expert team. Pass it through plant modification approval committee (Management of Change)

understood by every person concerned.   

Sampling and Gauging       Exposures of gases, vapours and dust while collecting samples. Approaching odd locations. Splashes and spillages while collecting samples. Exposures due to breaking of sight glasses and glass level indicators. Dip gauging of flammable liquids. Dip gauging of corrosive liquids. Hazards Due To Instrument Failures     Absence of fail safety instruments. Lack of interlocks and trip systems. Human failures in manual and semi automatic operations. Need for safety analysis of the instrumentation systems

For evaluation of safety aspects, the following steps are narrated: o Source of hazard. o Type of hazard

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o Control procedure o Contingency plan

Possible sources of hazard:  Handling and processing of inflammable and combustible raw materials  Handling of compressed gases.  Handling and processing of toxic substance  Handling of corrosive substances  Handling of oxidising substances  Operating electrical & mechanical - operated machineries for manufacture and testing of products  Handling of dust-producing equipment and also dust  Handling of boiler  Handling of various microorganisms in manufacture and also in testing of drugs  And several other operations in Pharmaceutical Industry for production and testing of drugs. Types of hazards:  Electrical shock.  Injury and death  Fire.  Chemical burn.  Infection.  Intoxication. Control Procedure:

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The framing of the control-procedure is an essential criterion in manufacturing houses so as to provide safe work environment in working place as well as to prevent accident. In pharmaceutical industry the manufacturing control procedures are prescribed in elaborate way as per the provision of Schedule M of the Drugs & Cosmetics Acts & Rules. Besides this the provisions of GMP (Good Manufacturing practices) and GLP (Good Laboratory Practices) are also adopted in to which covers total aspects of the factory i.e. building, plant set-up, process, personnel, Quality assurance, manufacturing control procedures, documentation etc. which certainly provide safe work environment. However the lapses or deviation in procedures lead to accidents hence the concerned personnel should always be alert to avoid lapse / deviation of even slight nature. Hence for ensuring total safe work environment and to prevent accident, the under mentioned control procedures may be adopted. a) Standard Operating Procedure (SOP) b) Safety Policy c) Monitoring d) Safety Audit e) Risk Analysis f) Preventive Maintenance g) Involvement of Personnel Standard Operating Procedure (SOP) :In the chemical industry SOP is prepared in more elaborate manner for manufacture of each formulation. All the processes are carried out within the prescribed operational parameters. It is of utmost importance to adhere to the SOP and all parameters, which automatically provide safety. Hence for total safety it is required to include critical points and relevant corrective 185

measures for all processes and also include the facilities provided in SOP with operating instructions. The SOP complete in all respects, ensures total safety in chemical industry.

Safety Policy:Besides processing, there are several sources (stated above) which may create accident. Hence it is imperative to define a safety policy and assigned the task to a safety officer. The safety policy is to be made as accident prevention and control programme to provide safety in factory and in office, too to each employee. This is drawn by considering all phases of company’s activities with the followings:  acceptable level of operational risks  standard of industrial hygiene  delegation of responsibility to employees as staff function  Process of alternation, modification or change in procedure in case of deviation or apprehension of accident  Steps to be taken in case of accident The Company’s safety policy should be hanged - up in notice board for information to all employees. Monitoring It is essential to monitor each & every operation for getting success. Hence all the processes & safety aspects must be monitored. It is also required to closely monitor the effectiveness of all safety tools on regular basis. On getting deviation or lapses, the cause is detected and the remedial measures are recommended for immediate implementation. Safety Audit Audit is an essential step to check the application of systems in true manner. Hence safety audit is to be done at regular interval so as to ensure the following-up of SOP with 186

parameters, critical points, safety aspects and all steps for prevention of accidents. In this respect, it is better to draw a ''safety audit format'' which will be helpful during auditing by ''safety officer'' or their authorized representative. Risk Analysis There are chances of occurring of several types of unwanted accidents in factory premises including office which may be fatal. (The sources of hazards have been already discussed above1.0) analysis in systemic manner by considering all aspects covering men, machine, processing, activities, building and all events including hazard due to human error or failure of any of the operation or tool. After evaluation of ''Risk Analysis'' the ''Safety measures'' are developed. Accordingly the safety aspects are incorporated in SOP and safety policy. Preventive maintenance Several accidents are avoidable by taking precautions and timely maintenance of machineries, building, pipelines etc. So effective maintenance programme will certainly eliminate accident. Accordingly preventive maintenance must be planned to overtone any dangerous situation. These aspects should be incorporated in SOP, Safety Audit format, safety Monitoring format and safety policy. Involvement of Personnel Most of the accidents are caused due to lapses on the part of person concerned. So it is imperative that the person concerned must be alert during work, which will present accident certainly. Hence it is most essential to involve all personnel in safety programme. All employees must be informed of safety policy and the concerned employees should be made fully aware about concerned safety aspects involved with him. (Processing/Machines/Chemicals/Microrganisms handled by him). It is also required to motivate employees by arranging workshop/Seminar on safety aspects and also by presentation of awards for accident free performance. Time to time all employees should be 187

appraised about new development on safety and also about accident prevention programme. They should be provided with preprinted instruction sheets and checklist for their operation and working area.

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Contingency Plan: There is a need to prepare ''Contingency Plan'' for dealing with accidents in factory, which may occur and are likely to affect life and property, both within the industry and in the immediate neighborhood. So each industry has to formulate an on-site "Emergency Management Plan" detailing explicitly action to be taken and by whom in the event of accident occurring on site. It should contain in detail the problem, rapid control, action to prevent from further escalation, and all control procedures so as to prevent damage to life, Property and environment. In a nutshell it is concluded that safety / aspects must be considered by pharmaceutical manufacturer in the interest of employees, firm property and immediate neighborhood. The source of possible hazards, risk analysis, control-procedures, preventive measures & contingency plan are the main five essential steps for ensuring accident free as well as complete safe environment in factory. Documentation is also a supportive tool in safety programme. All the manufacturers should follow safety aspects in their factory.

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SAFE OPERATING PROCEDURE COMPRESSED AIR 1. 2. Before starting the compressor, be sure the manual and all warning signs have been completely read. Pipes should be properly labeled that carry compressed air and the direction of air flow correctly labeled with an arrow. Shutoff valves should be properly labeled and identified so air can be shut off quickly in an emergency situation. 3. 4. compressed air. 5. fail. 6. 7. High pressure jacketed lines should be anchored at several points to prevent them from whipping. Quick disconnect fittings should be installed on flexible air hoses in high fire hazard areas; the hoses can be disconnected quickly, preventing whipping actions that might not only cause injury and damage but also stoke a fire. 8. whenever possible. 9. compressor does. 10. DO NOT use compressed air to:  Transfer flammable liquids.  Static electricity build-up can discharge and ignite the liquid.  Empty containers. The container could rupture due to excessive internal pressure.  Clean clothes, hair, or skin. When using compressed air, direct air away from eyes and skin. Vacuuming stirs up less dust and other particles than an air Use a vacuum system rather than compressed air for cleaning Flexible air hoses should be kept as short as possible to minimize tripping hazards and to reduce whipping action in the event a hose would Hoses, fittings, regulators, and valves should be inspected periodically for leaks, damage, and other defects. Goggles must be worn over safety glasses when cleaning with

190

12.

To reduce noise exposure and prevent exhaust from the equipment or tool, direct the pressure relief valve away from work areas.

Photographs of mock drill

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192

Statutory obligation as per Factories Act
Factories rules in Andhra Pradesh.
Sec-21 All the moving parts of the machinery to be fenced / guarded. Sec-22 (1) Trained adult workers register. Adult workers register NA Periodical inspection on Machine guarding. Issue records.

Obligation /Requirements in brief.

Documents To be submitted / Legal Requirements.

Internal Records

Sec-29

Lifting machines (Hoist and Lifts)

Form-37 Certified by a competent person once in 12 Months. Form-8, External inspection once in 6 months/ Thorough internal inspection once in 12 months and hydrostatically testing once in 4 years.

Form-37

Sec-31

Any equipment operated at above atmospheric pressure. Should be certified by a competent person.

Form-8

Sec-32

Floors ,Stairs, means for access should be kept free from obstructions.

NA

Floor wise plans

Sec-33

Pits, Sumps, openings in the floor are to be covered /fenced.

NA

NA

Sec-34

No person is allowed to lift heavy weights that are likely to cause injury.

Sec-35

Goggles are to be provided for protection of eyes where there is a risk of injury or exposure to excess light.

Selection procedure for procuring the PPE.

Issue records at stores/Production Blocks.

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Sec-36

No person is allowed to work in confined space where dangerous fumes, gasses etc may present.

Vessel entry permits system in practice.

Vessel entry permits record.

Sec-37(4)

Permit for Welding / Hot Jobs.

Hot work permit system in practice.

Hot work permit records.

Sec-38(1)

Practical measures adopted to prevent fire, Safety measures for escape in case of fire.

Earthing/Earth continuity /FLP elecrical equipments/Emergency escape routes/Lightening arrestors/Storage of flammable chemicals.. Fire Buckets/ Fire extinguishers/Fire hydrant system/Fire alarm system. Lay-outs of the emergency exits on the plans of each floor. Structural stability certificates duly certified by a third competent person.

Earth continuity/Earth pit records/Emergecny escape routes.

Sec-38(1)

Precautions in case of fire.

Maintenance records.

Sec-38(2)

Every worker should be made familiar with means of escape in case of fire.

Lay-outs with emergency exits marking. Repairs and maintenance of the Buildings including white wash or color wash. NA

Sec-40

Safety of the Buildings and Machinery, Maintenance of the Buildings.

Sec-40 B

1000 or more employees or processes involves any risk of bodily injury are liable to maintain a Safety officer on the recommendation of factories inspectorate. Compulsory disclosure of the information by occupier regarding dangers and health hazards due to exposure in the work environment.

Qualifications and experiences of the Safety officer must match with the act and rule recommendations.

Sec-41(B)

Safety and Health Policy.

Safety and Health Policy.

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Sec-41(b)

Preparation of on-site emergency plan and training the employees on the same by doing the mock drills.

OSEP

OSEP / Emergency response team members training and mock drills.

Sec-41 C (a)

Health records of the persons exposed to chemicals are to be available for employees.

Health Records of the individual employees.

Health Records of the individual employees.

Sec-41 C (b)

Qualified and experience persons to be appointed for handling hazardous substances. Medical examination of every worker in hazardous area is to be done. Before engaging on hazardous process and while ceasing from the works interval time is not less than 12 months. Monitor permissible exposure limits of chemicals and toxic substances in manufacturing process.

List of the qualified personnel working over the hazardous substances. Medical records of the individual employees.(Health surveillance Records)

List of the qualified personnel working over the hazardous substances. Medical records of the individual employees.(Health surveillance Records)

Sec-41 C (c)

Sec-41-F

LEL,UEL/TLV Monitoring records.

LEL,UEL/TLV Monitoring records.

Sec-41-G

Equal participation of employees in safety committee comparing with the management staff. Notice of certain dangerous occurrence. Notice of certain accidents causing bodily injury.

Safety committee minutes.

Safety committee minutes.

Sec-88 Sec-88A

Form-18 Form-18

Form-18 Form-18

Sec-89

Notice of certain diseases in Third Schedule contracted by employees.

Sec-108

Display of abstract of Factories Act and rules.A

Abstract.

Abstract

Check lists for operation
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SAFETY AND HEALTH PROGRAM

Do you have an active safety and health program in operation that deals with general safety and health program elements as well as management of hazards specific to your worksite? Is one person clearly responsible for the overall activities of the safety and health program? Do you have a safety committee or group made up of management and labor representatives that meets regularly and reports in writing on its activities? Do you have a working procedure for handling in-house employee complaints regarding safety and health? Are you keeping your employees advised of the successful effort and accomplishments you and/or your safety committee have made in assuring they will have a workplace that is safe and healthful? Have you considered incentives for employees or workgroups who have excelled in reducing workplace injuries/illnesses?

Hazard communication

An explanation of what an MSDS is and how to use and obtain one? MSDS contents for each hazardous substance or class of substances? Explanation of "Right to Know?" Identification of where an employee can see the employers written hazard communication program and where hazardous substances are present in their work areas? The physical and health hazards of substances in the work area, and specific protective measures to be used? Details of the hazard communication program, including how to use the labeling system and MSDS's? How to recognize tasks that might result in occupational exposure?

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How to use work practice and engineering controls and personal protective equipment and to know their limitations? How to obtain information on the types selection, proper use, location, removal handling, decontamination, and disposal of personal protective equipment? Who to contact and what to do in an emergency?

Elevated Surfaces

Are signs posted, when appropriate, showing the elevated surface load capacity? Are surfaces elevated more than 30 inches above the floor or ground provided with standard guardrails? Are all elevated surfaces (beneath which people or machinery could be exposed to falling objects) provided with standard 4-inch toeboards? Is a permanent means of access and egress provided to elevated storage and work surfaces? Is required headroom provided where necessary? Is material on elevated surfaces piled, stacked or racked in a manner to prevent it from tipping, falling, collapsing, rolling or spreading? Are dock boards or bridge plates used when transferring materials between docks and trucks or rail cars?

Stairs and Stairways

Are standard stair rails or handrails on all stairways having four or more risers? Are all stairways at least 22 inches wide?

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Do stairs have landing platforms not less than 30 inches in the direction of travel and extend 22 inches in width at every 12 feet or less of vertical rise? Do stairs angle no more than 50 and no less than 30 degrees? Are step risers on stairs uniform from top to bottom? Are steps on stairs and stairways designed or provided with a surface that renders them slip resistant? Are stairway handrails located between 30 and 34 inches above the leading edge of stair treads? Do stairway handrails have at least 3 inches of clearance between the handrails and the wall or surface they are mounted on? Where doors or gates open directly on a stairway, is there a platform provided so the swing of the door does not reduce the width of the platform to less than 21 inches? Where stairs or stairways exit directly into any area where vehicles may be operated, are adequate barriers and warnings provided to prevent employees stepping into the path of traffic? Do stairway landings have a dimension measured in the direction of travel, at least equal to the width of the stairway? Floor and Wall Openings

Are floor openings guarded by a cover, a guardrail, or equivalent on all sides (except at entrance to stairways or ladders)? Are toeboards installed around the edges of permanent floor openings (where persons may pass below the opening)? Are skylight screens of such construction and mounting that they will withstand a load of at least 200 pounds? Is the glass in the windows, doors, glass walls, etc., which are subject to human impact, of sufficient thickness and type for the condition of use?

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Are grates or similar type covers over floor openings such as floor drains of such design that foot traffic or rolling equipment will not be affected by the grate spacing? Are unused portions of service pits and pits not actually in use either covered or protected by guardrails or equivalent? Are manhole covers, trench covers and similar covers, plus their supports designed to carry a truck rear axle load of at least 20,000 pounds when located in roadways and subject to vehicle traffic? Are floor or wall openings in fire resistive construction provided with doors or covers compatible with the fire rating of the structure and provided with a self-closing feature when appropriate? Walkways

Are aisles and passageways kept clear? Are aisles and walkways marked as appropriate? Are wet surfaces covered with non-slip materials? Are holes in the floor, sidewalk or other walking surface repaired properly, covered or otherwise made safe? Is there safe clearance for walking in aisles where motorized or mechanical handling equipment is operating? Are materials or equipment stored in such a way that sharp projectives will not interfere with the walkway? Are spilled materials cleaned up immediately? Are changes of direction or elevation readily identifiable? Are aisles or walkways that pass near moving or operating machinery, welding operations or similar operations arranged so employees will not be subjected to potential hazards? Is adequate headroom provided for the entire length of any aisle or walkway?

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Are standard guardrails provided wherever aisle or walkway surfaces are elevated more than 30 inches above any adjacent floor or the ground? Are bridges provided over conveyors and similar hazards?

General Work Environment

Is a documented, functioning housekeeping program in place? Are all worksites clean, sanitary, and orderly? Are work surfaces kept dry or is appropriate means taken to assure the surfaces are slipresistant? Are all spilled hazardous materials or liquids, including blood and other potentially infectious materials, cleaned up immediately and according to proper procedures? Is combustible scrap, debris and waste stored safely and removed from the worksite properly? Are accumulations of combustible dust routinely removed from elevated surfaces including the overhead structure of buildings, etc.? Is combustible dust cleaned up with a vacuum system to prevent the dust from going into suspension? Is metallic or conductive dust prevented from entering or accumulating on or around electrical enclosures or equipment? Are covered metal waste cans used for oily and paint-soaked waste?

ELECTRICAL

Are all employees required to report as soon as practicable any obvious hazard to life or property observed in connection with electrical equipment or lines?

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Are employees instructed to make preliminary inspections and/or appropriate tests to determine what conditions exist before starting work on electrical equipment or lines? When electrical equipment or lines are to be serviced, maintained or adjusted, are necessary switches opened, locked-out and tagged whenever possible? Are portable electrical tools and equipment grounded or of the double insulated type? Are electrical appliances such as vacuum cleaners, polishers, and vending machines grounded? Do extension cords being used have a grounding conductor? Are multiple plug adaptors prohibited? Are ground-fault circuit interrupters installed on each temporary 15 or 20 ampere, 120 volt AC circuit at locations where construction, demolition, modifications, alterations or excavations are being performed? Are all temporary circuits protected by suitable disconnecting switches or plug connectors at the junction with permanent wiring? Is exposed wiring and cords with frayed or deteriorated insulation repaired or replaced promptly? Are flexible cords and cables free of splices or taps? Are clamps or other securing means provided on flexible cords or cables at plugs, receptacles, tools, equipment, etc., and is the cord jacket securely held in place? Are all cord, cable and raceway connections intact and secure? In wet or damp locations, are electrical tools and equipment appropriate for the use or location or otherwise protected? Is the location of electrical power lines and cables (overhead, underground, underfloor, other side of walls) determined before digging, drilling or similar work is begun? Are metal measuring tapes, ropes, handlines or similar devices with metallic thread woven into the fabric prohibited where they could come in contact with energized parts of equipment or circuit conductors? Is the use of metal ladders prohibited in areas where the ladder or the person using the ladder could come in contact with energized parts of equipment, fixtures or circuit conductors?

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Are all disconnecting switches and circuit breakers labeled to indicate their use or equipment served? Are disconnecting means always opened before fuses are replaced? Do all interior wiring systems include provisions for grounding metal parts of electrical raceways, equipment and enclosures? Are all electrical raceways and enclosures securely fastened in place? Are all energized parts of electrical circuits and equipment guarded against accidental contact by approved cabinets or enclosures? Is sufficient access and working space provided and maintained about all electrical equipment to permit ready and safe operations and maintenance? Are all unused openings (including conduit knockouts) in electrical enclosures and fittings closed with appropriate covers, plugs or plates? Are electrical enclosures such as switches, receptacles, and junction boxes, provided with tightfitting covers or plates? Are disconnecting switches for electrical motors in excess of two horsepower, capable of opening the circuit when the motor is in a stalled condition, without exploding? (Switches must be horsepower rated equal to or in excess of the motor hp rating.) Is low voltage protection provided in the control device of motors driving machines or equipment which could cause probable injury from inadvertent starting? Is each motor disconnecting switch or circuit breaker located within sight of the motor control device? Is each motor located within sight of its controller or the controller disconnecting means capable of being locked in the open position or is a separate disconnecting means installed in the circuit within sight of the motor? Is the controller for each motor in excess of two horsepower, rated in horsepower equal to or in excess of the rating of the motor it serves? Are employees prohibited from working alone on energized lines or equipment over 600 volts?

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CONFINED SPACES

Are confined spaces thoroughly emptied of any corrosive or hazardous substances, such as acids or caustics, before entry? Are all lines to a confined space, containing inert, toxic, flammable, or corrosive materials valved off and blanked or disconnected and separated before entry? Are all impellers, agitators, or other moving parts and equipment inside confined spaces locked-out if they present a hazard? Is either natural or mechanical ventilation provided prior to confined space entry? Are appropriate atmospheric tests performed to check for oxygen deficiency, toxic substances and explosive concentrations in the confined space before entry? Is adequate illumination provided for the work to be performed in the confined space? Is the atmosphere inside the confined space frequently tested or continuously monitored during conduct of work? Is there an assigned safety standby employee outside of the confined space. when required, whose sole responsibility is to watch the work in progress, sound an alarm if necessary, and render assistance? Is the standby employee appropriately trained and equipped to handle an emergency? Is the standby employee or other employees prohibited from entering the confined space without lifelines and respiratory equipment if there is any question as to the cause of an emergency? Is approved respiratory equipment required if the atmosphere inside the confined space cannot be made acceptable Is all portable electrical equipment used inside confined spaces either grounded and insulated, or equipped with ground fault protection? Before gas welding or burning is started in a confined space, are hoses checked for leaks, compressed gas bottles forbidden inside of the confined space, torches lighted only outside of the confined area and the confined area tested for an explosive atmosphere each time before a lighted torch is to be taken into the confined space? If employees will be using oxygen-consuming equipment-such as salamanders, torches, and

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furnaces, in a confined space-is sufficient air provided to assure combustion without reducing the oxygen concentration of the atmosphere below 19.5 percent by volume? Whenever combustion-type equipment is used in a confined space, are provisions made to ensure the exhaust gases are vented outside of the enclosure? Is each confined space checked for decaying vegetation or animal matter which may produce methane? Is the confined space checked for possible industrial waste which could contain toxic properties? If the confined space is below the ground and near areas where motor vehicles will be operating, is it possible for vehicle exhaust or carbon monoxide to enter the space? LOCKOUT/TAGOUT PROCEDURES

Is all machinery or equipment capable of movement, required to be de-energized or disengaged and locked-out during cleaning, servicing, adjusting or setting up operations, whenever required? Where the power disconnecting means for equipment does not also disconnect the electrical control circuit: Are the appropriate electrical enclosures identified? Is means provided to assure the control circuit can also be disconnected and locked-out? Is the locking-out of control circuits in lieu of locking-out main power disconnects prohibited? Are all equipment control valve handles provided with a means for locking-out? Does the lock-out procedure require that stored energy (mechanical, hydraulic, air, etc.) be released or blocked before equipment is locked-out for repairs? Are appropriate employees provided with individually keyed personal safety locks? Are employees required to keep personal control of their key(s) while they have safety locks in use?

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Is it required that only the employee exposed to the hazard, place or remove the safety lock? Is it required that employees check the safety of the lock-out by attempting a startup after making sure no one is exposed? Are employees instructed to always push the control circuit stop button immediately after checking the safety of the lock-out? Is there a means provided to identify any or all employees who are working on locked-out equipment by their locks or accompanying tags? Are a sufficient number of accident preventive signs or tags and safety padlocks provided for any reasonably foreseeable repair emergency? When machine operations, configuration or size requires the operator to leave his or her control station to install tools or perform other operations, and that part of the machine could move if accidentally activated, is such element required to be separately locked or blocked out? In the event that equipment or lines cannot be shut down, locked-out and tagged, is a safe job procedure established and rigidly followed? Powder-Actuated Tools

Are employees who operate powder-actuated tools trained in their use and carry a valid operator's card? Is each powder-actuated tool stored in its own locked container when not being used? Is a sign at least 7 inches by 10 inches with bold face type reading "POWDER-ACTUATED TOOL IN USE" conspicuously posted when the tool is being used? Are powder-actuated tools left unloaded until they are actually ready to be used? Are powder-actuated tools inspected for obstructions or defects each day before use? Do powder-actuated tool operators have and use appropriate personal protective equipment such as hard hats, safety goggles, safety shoes and ear protectors? PERSONAL PROTECTIVE EQUIPMENT

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Are employers assessing the workplace to determine if hazards that require the use of personal protective equipment (for example, head, eye, face, hand, or foot protection) are present or are likely to be present? If hazards or the likelihood of hazards are found, are employers selecting and having affected employees use properly fitted personal protective equipment suitable for protection from these hazards? Has the employee been trained on ppe procedures, that is, what ppe is necessary for a job task, when they need it, and how to properly adjust it? Are protective goggles or face shields provided and worn where there is any danger of flying particles or corrosive materials? Are approved safety glasses required to be worn at all times in areas where there is a risk of eye injuries such as punctures, abrasions, contusions or burns? Are employees who need corrective lenses (glasses or contacts) in working environments having harmful exposures, required to wear only approved safety glasses, protective goggles, or use other medically approved precautionary procedures? Are protective gloves, aprons, shields, or other means provided and required where employees could be cut or where there is reasonably anticipated exposure to corrosive liquids, chemicals, blood, or other potentially infectious materials? See 29 CFR 1910.1030(b) for the definition of "other potentially infectious materials." Are hard hats provided and worn where danger of falling objects exists? Are hard hats inspected periodically for damage to the shell and suspension system? Is appropriate foot protection required where there is the risk of foot injuries from hot, corrosive, or poisonous substances, falling objects, crushing or penetrating actions? Are approved respirators provided for regular or emergency use where needed? Is all protective equipment maintained in a sanitary condition and ready for use? Do you have eye wash facilities and a quick drench shower within the work area where employees are exposed to injurious corrosive materials? Where special equipment is needed for electrical workers, is it available?

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Where food or beverages are consumed on the premises, are they consumed in areas where there is no exposure to toxic material, blood, or other potentially infectious materials? Is protection against the effects of occupational noise exposure provided Are adequate work procedures, protective clothing and equipment provided and used when cleaning up spilled toxic or otherwise hazardous materials or liquids? Are there appropriate procedures in place for disposing of or decontaminating personal protective equipment contaminated with, or reasonably anticipated to be contaminated with, blood or other potentially infectious materials? Portable (Power Operated) Tools and Equipment Are grinders, saws and similar equipment provided with appropriate safety guards? Are power tools used with the correct shield, guard, or attachment, recommended by the manufacturer? Are portable circular saws equipped with guards above and below the base shoe? Are circular saw guards checked to assure they are not wedged up, thus leaving the lower portion of the blade unguarded? Are rotating or moving parts of equipment guarded to prevent physical contact? Are all cord-connected, electrically operated tools and equipment effectively grounded or of the approved double insulated type? Are effective guards in place over belts, pulleys, chains, sprockets, on equipment such as concrete mixers, and air compressors? Are portable fans provided with full guards or screens having openings ½ inch or less? Is hoisting equipment available and used for lifting heavy objects, and are hoist ratings and characteristics appropriate for the task? Are ground-fault circuit interrupters provided on all temporary electrical 15 and 20 ampere circuits, used during periods of construction? Are pneumatic and hydraulic hoses on power operated tools checked regularly for deterioration or damage?

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FLAMMABLE AND COMBUSTIBLE MATERIALS Are combustible scrap, debris, and waste materials (oily rags, etc.) stored in covered metal receptacles and removed from the worksite promptly? Is proper storage practiced to minimize the risk of fire including spontaneous combustion? Are approved containers and tanks used for the storage and handling of flammable and combustible liquids? Are all connections on drums and combustible liquid piping, vapor and liquid tight? Are all flammable liquids kept in closed containers when not in use (for example, parts cleaning tanks, pans, etc.)? Are bulk drums of flammable liquids grounded and bonded to containers during dispensing? Do storage rooms for flammable and combustible liquids have explosion-proof lights? Do storage rooms for flammable and combustible liquids have mechanical or gravity ventilation? Is liquefied petroleum gas stored, handled, and used in accordance with safe practices and standards? Are "NO SMOKING" signs posted on liquefied petroleum gas tanks? Are liquefied petroleum storage tanks guarded to prevent damage from vehicles? Are all solvent wastes and flammable liquids kept in fire-resistant, covered containers until they are removed from the worksite? Is vacuuming used whenever possible rather than blowing or sweeping combustible dust? Are firm separators placed between containers of combustibles or flammables, when stacked one upon another, to assure their support and stability? Are fuel gas cylinders and oxygen cylinders separated by distance, and fire-resistant barriers, while in storage? Are fire extinguishers selected and provided for the types of materials in areas where they are to be used? Class A Ordinary combustible material fires. Class B Flammable liquid, gas or grease fires.

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Class C Energized-electrical equipment fires. Are appropriate fire extinguishers mounted within 75 feet of outside areas containing flammable liquids, and within 10 feet of any inside storage area for such materials? Are extinguishers free from obstructions or blockage? Are all extinguishers serviced, maintained and tagged at intervals not to exceed 1 year? Are all extinguishers fully charged and in their designated places? Where sprinkler systems are permanently installed, are the nozzle heads so directed or arranged that water will not be sprayed into operating electrical switch boards and equipment? Are "NO SMOKING" signs posted where appropriate in areas where flammable or combustible materials are used or stored? Are safety cans used for dispensing flammable or combustible liquids at a point of use? Are all spills of flammable or combustible liquids cleaned up promptly? Are storage tanks adequately vented to prevent the development of excessive vacuum or pressure as a result of filling, emptying, or atmosphere temperature changes? Are storage tanks equipped with emergency venting that will relieve excessive internal pressure caused by fire exposure? Are "NO SMOKING" rules enforced in areas involving storage and use of hazardous materials? Hand Tools and Equipment Are all tools and equipment (both company and employee owned) used by employees at their workplace in good condition? Are hand tools such as chisels and punches, which develop mushroomed heads during use, reconditioned or replaced as necessary? Are broken or fractured handles on hammers, axes and similar equipment replaced promptly? Are worn or bent wrenches replaced regularly? Are appropriate handles used on files and similar tools? Are employees made aware of the hazards caused by faulty or improperly used hand tools?

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Are appropriate safety glasses, face shields, etc. used while using hand tools or equipment which might produce flying materials or be subject to breakage? Are jacks checked periodically to ensure they are in good operating condition? Are tool handles wedged tightly in the head of all tools? Are tool cutting edges kept sharp so the tool will move smoothly without binding or skipping? Are tools stored in dry, secure locations where they won't be tampered with? Is eye and face protection used when driving hardened or tempered spuds or nails?

Different types of Reactor photos

MS Coiled reactor with motor and gear box

Measuring receiver

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SS Coiled reactor with motor and gear box

Inside the reactor

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Thermal Resisting reactor

SS reactor with MS Jacket

Glass reactors

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Reactors
Reactor is a vital piece of equipment commonly used in industries for carrying out chemical reactions and is the heart of any process Industry. There are various types of reactors used in chemical industry, depending on the requirement. These Include batch reactors, semi continuous reactors, continuous reactors etc. Here in our factory we are using Batch Reactors to meet our requirements. Generally a batch reactor is a vessel fitted with heating/cooling jackets/coils, agitation arrangements as per requirements of the reactions. General safety guidelines regarding batch reactor? are; The operations carried out in a batch reactor need dose monitoring of process Parameters from both in safety and quality view of angle. Non-adherence to set parameters In a batch reactor operation can sometimes lead to dangerous situations like runaway reactions, release of flammable/toxic gases in the work place, spoilage of the batch, etc.  Follow the instructions in 'Batch Production Report' (BPR).  Provide belt coupling drive guards and motor fan covers. Reactors should be provided with temperature and pressure/vacuum gauge according to the working condition. Steam line should also be provided with pressure and temperature gauge to indicate the same.

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Since the Production Block working atmosphere contains flammable vapours, use 'flame proof electrical appliances like FLP Motor, FLP Temperature indicator, FLP Starter, FLP View lamp, FLP Light fixtures including Emergency Lamp. Use Boro silicate glass as view glass, which can with stand pressure up to 15 Kgs/Cm2. Since there is splashing/Turbulence of materials inside the reactor with solvent media, there is a chance of static generation, in the shell of the reactor. So In order to drain out that charges proper equipment earthing should be done. Also provide proper electrical earthing to avoid electrical shocks. 1. Safety pressure relief valve and rupture disc should be provided in Order to relieve the excess pressure generated in case of exothermic 'runaway reactions. 2. Monitoring and controlling of temperature is an important and critical element because it is observed that a rise in temperature of about 10DC can double the rate of reaction, which can lead to runaway situations and resulting in loss of control in operation, fire and explosion. 3. Vent termination of the reactor should be taken outside of the production block to avoid the accumulation of fumes in side of production blocks. If the concentration and generation of the fumes are more, it should be passed through a scrubber in which a suitable scrubbing media may be maintained. 4. Keep the reactor clean, because the presence of contaminants can cause over pressurization in the reactor due to undesirable reactions. The contaminants that normally enter into the reactor are moisture, water, metal oxides and other impurities. The presence of water content even in a small quantity can be dangerous, while handling chemicals like Sodium Hydride. The route of entry of contaminants into the reactor are transfer tines such as flexible metal hoses, materials stored for a prolonged period and charged, open manholes or even when the reactor remains idle for a long period, 5. For water sensitive reactions,  It is necessary to remove the moisture from the reactor by steam heating and rinsing with suitable solvents before charging the reactor.  Manhole covers should be kept closed to avoid the entry of contaminants.

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 Hose pipes (Use only metallic, PVC and Other rubber pipes will generate static charges while transferring the solvents through them.) used for charging should be property maintained and stored,  Care should be taken to ensure that the hoses are free of water or other chemicals. • The roof of the building where the batch reactors are installed should be maintained properly to avoid the ingress of water and other contaminants. • Heating or cooling of batch reactor should be done gradually to avoid thermal stresses in the shell of the reactor.

Inspection and Maintenance
Periodical inspection and maintenance are essential for the safe and efficient working of the reactor. Inadequate and faulty maintenance may cause failure of the reactor resulting into major accidents and huge losses due to escape of hazardous chemicals into the atmosphere. Some of the points to be followed are; 1. Excessive tightening of gland packing of agitators (anchors) seats can lead to early wear and tear, may create fire due to friction, resulting generation of toxic gases/vapours from the reactor to the atmosphere. 2. Inspect anchor and shaft of the reactor after every batch. Damaged anchor and/or shaft can lead to Improper mixing of the reactants in the reactor and can develop hot spots or uncontrolled exothermic reactions. 3. Safety valves and pressure relief valves should be kept free of corrosion or fouling. Also, they are to be tested periodically as per the statutory norms, it is must to ensure their effective functioning. A. Periodical calibration of pressure and temperature gauges are also essential in order to avoid faulty readings. 5. Thickness of the reactor shell is to be done periodically, as the thickness can get reduced over a time due to corrosion/erosion leading to failure of the reactor, 6. Pressure/Vacuum testing of the reactor needs to be done at a regular interval to check the strength of the reactor working under pressure or vacuum. 7. Proper maintenance should be there for the heating/cooling system, In order to

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avoid temperature fluctuations in the rector and w prevent the thermal stresses, which will weaken the reactor shell.

Centrifuge:
High speed centrifugal equipment is frequently used in the manufacturing process to separate solids from Liquids or for other duties such as extraction- When flammable liquids are involved, the potential hazard form Ignition by factional heat, spark or static electricity is very high. It is essential to protect from these hazards. Centrifuge can be operated safely by Inerting with nitrogen. Nitrogen inertisation provision is to be used for this purpose. As the equipment is running at high speed the lid should not be opened for charging or it should not be opened In between die centrifuge operation unless it is stopped. For this purpose the lid is equipped with lid interlock which cut of the power supply to the motor when the lid is open. This provision should not be misused or tapped under any circumstances. Break also has this type of interlocking to prevent applying break while motor is running. In addition to this all centrifuges are equipped with inertisation provision to inert the centrifuge before stating of centrifuge. All operating personnel should thoroughly trained to understood the safety concept behind providing interlocks and to maintain properly, filtered mother liquors are to be collected in a closed tub to prevent escape of solvent vapours from the centrifuge- All centrifuges are well equipped with earthling to prevent accumulation of static generation. Mechanical hazards: Out of balance, bearing failure, metal to metal contact at high speed, compatibility of material are the general causes which can cause friction and generate spark. In the flammable atmosphere spark may create fire. Fire and explosion hazards: Dangerous concentrations of vapours can accumulate rapidly within a centrifuge system after a flammable liquid is introduced either In the feed or as a wash medium. Risk is high the hazardous conditions can persist throughout entire cycle of operations and even after the rotor has come to nest. A fire or Explosion can occur if an ignition source is present

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Safety precautions for operation of centrifuge
1. Always follow nitrogen purge cycle when starting up a centrifuge handling flammable solvents. 2. Never run the unit with the cover In the Open position, and the interlock bypassed. An open cover allows the escape of solvent vapours, which may be flammable and /or irritating. It also provides the possibility for a tool to fall into the spinning basket and then be flung dangerously through the air. 3, Never put your hand inside a centrifuge while the basket is in motion. Ensure zero stop before opening of the lid. 4, Proper balance of the load in the basket is of great Importance. If there is excessive vibration as the basket gains speed during start up or while it is being loaded, stop the machine promptly and re-distribute the load. 5. 6. Report any roughness of operation or signs of corrosion to your supervisor. Dynamic balance test must be done before commissioning or after every major maintenance.

Filters
Filters are not widely used by the industry, preference being given to centrifuges. However, in those instances where they are preferred on flammable liquid duties,, they should be fully enclosed. Pressure filters, such as plate and frame leaf, should be provided with guards to prevent leakage spraying in to the atmosphere. Pressure relief in the form of a bursting disc should be provided. If liquor is to be driven out of the filter partially to dry the solids, inert gas should be used. The equipment should be situated in a well ventilated plant area, and closely supervised during Operation.

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DRIERS
Virtually all types of driers are used by the chemical Industry. Fire and explosion hazards exist whenever flammable solvents or explosive solids are processed.

Tray Driers:
The air flow through tray driers should be single pass and sufficient at all times to ensure that the solvent concentration remains below 25% of the lower explosive limit at all points. The practice of recirculation of air should be avoided; it is rarely justified by increase in efficiency. By encouraging the solvent vapours level to increase and by depositing dust on to the heaters where it may decompose to form a source of Ignition, It can create a hazardous situation. Tray Driers operating with hazardous materials should be fitted with an alarm to indicate air flow failure, based on an air flow measurement. They should also be explosion vented, but it is rarely possible to regard the exhaust stack as an explosion vent, since it is neither large enough nor correctly oriented. Tray Driers are normally rectangular, and consequently unable to resist even slight explosion pressures. They have large doors and even with strengthening will only resist pressures of very little. A very large vent is required to protect them, often equal in area to almost one whole side of the drier. The vent must discharge to a safe isolated area outside the building in which the drier Is Installed. All the driers are equipped with break limit switch and temperature Indicator along with explosion flap to take care of emergency. Care is taken while loading and unloading of material inside die drier.

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Rotary cone vacuum drier:

 Demarcated by a barrier.  Vacuum should be released by using filtered nitrogen.

 Earthing should be intact  Interlocking, of guard should be intact

Special precautions for chemical industries
Working with flammable liquids: Hazards:
Charging of the liquid when it flows along with the walls of transfer lines (pipes) or flexible tubes. Charging of pipe or tube or adjacent parts outside the pipe. Discharge of sparks between metal pats e.g, tube fittings and containers.

Measures;
 Avoid formation of explosive mixtures within the pipe by having the pipe (tube,pipe) completely filled.  Keep velocity low when discharging liquids into containers. It should never be more than 30 L/mt through the hose pipe of 25 mm die & not more than 115 L/mt through 50 mm hose pipe.  Keep the liquids pure, Dust and droplets of water are charge earners and can generate considerable change.

Filling and Emptying Drums by Hand:
Transfer of flammable liquids to other smaller containers.

Hazards :

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Charging of liquid and the container due to separation (flow ). Discharge of sparks between metal parts of drum and the can or between can and funnel

Measures
 Earth metal drum or place them on earthed metal grating-Take filling pipe of funnel right down to the bottom to avoid free fall to minimize splashing & spraying. Employee has to wear conductive shoes.  When filling it in HDPE drums/ small cans, earth rod must be kept inside the drum before startup of filling operation. It is to be removed at the end of Operation.

Transfer of solvents from vehicle (tankers) to storage tanks : Hazards:
Charging of the liquid due to flow and charging of the vehicle. Discharging with sparks between conductive parts e.g, between hose fittings and vehicle or between driver and tank or vehicle-

Measures:
   Connect vehicle and tank with earthed conductor. Use conductive tube/hose. Wear conductive shies.

Filling of Agitator vessels with flammable solvents: Hazards: Charge develops in liquid due to splashing, whirling. Discharge with sparks above liquid surface is possible, Measures:
 Inertise vessel with N2. Use of CO2 is not recommended due to formation of dry ice.

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 Extend filling cube right down to the vessel or let it be as near to the side wall.  Draw the solvent with the aid of vacuum/air operated double diaphragm pump.

Feeding of solid material to an agitator vessel or reaction tank pre-loaded with flammable solvent. Hazards:
Charge develops due to stirring process, feeding of the material, Discharges with sparks at the manhole or above the surface of the liquid,

Measures:
 If possible, load solids first.  If possible cool solvent at least 10°C below its flash point.  Add powder through rotary valve or such equipment which prevent direct fall of a large quantity of powder.  Wear fire retardant suit while charging.  Inertise vessel with NZ. Use of CO2 Is not recommended due to formation of dry Ice.

Operations at the open manhole of a filled vessel; Hazards:
Charged reaction masses, inside the vessel/agitator tank can discharge with sparks via a metal object such as. Sampler or measuring nod introduced in the tank. The higher ignition hazard is near the man hole where solvent vapours mix with air.

Measures:
 Before opening the manhole, stop the agitator and wait for five minutes. Inertise the vessel or /switch or exhaust ventilators, if fitted on the vessel, for a few seconds before opening the manhole  Use sample beaker or measuring rods made of insulating material. Wooden measuring rods are acceptable. Keep sampling beakers clean.

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Centrifuge:
Hazards:
High charge develop due to  High speed of the rotating parts,  Use of non-conductive liners or coatings e.g, synthetic fiber cloths, rubber-Fined bins  Intensive separating process between solid and liquid components. The presence of flammable vapours or aerosols with high turbulence. sparks capable of ignition with cause fire or explosion.

Measures:
 Centrifuge machines with insulation internal coating must riot be used with flammable solvents  All metal parts must be earthed.  Inertise the centrifuge, when called for.  With draw cloth (synthetic fibers) slowly in order to prevent charging. Any abnormality in function of equipment after changing over shall be immediately reported to the concerned. Emergency lights which are on standby UPS provided in the production block shall light up instantaneously with power failure. Any delay in the system must be reported immediately to the shift electrical engineer on duty.

MATERIAL HANDLING
Raw Materials Raw materials by virtue of its physical properties will be classified as  Solids (Lumps, Crystals, Flakes and Powder]  Semi solids   Liquids Gases

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By virtue of the chemical characteristics, they can be classified as  Explosives  Flammable  Non-flammable  Toxic   Oxidizers Corrosive

Mode of receipt: Raw materials are received by goods vehicles and mobile tankers. Mode of packing:
  Sacs Drums  Tins  Carboys  Cylinders (liquid, gases)

Safe handling of Raw Materials
1. Before handling a chemical know its physical and chemical properties. 2. Procure Material Safety Data Sheet (M5DS) of the new material from the manufacturer. 3. Compulsorily use PPEs like hand gloves, goggles, aprons, gumshoes, helmets etc. 4. Store the chemicals away from heat sources like reactors, boilers, steam lines, heat exchangers, ovens, NFLP power switches, etc 5. Do not store incompatible chemicals together to avoid reactions. 6. Ensure proper ventilation and lighting in the chemical storage. 7. Store the chemical drums/carboys/chemical bags etc on pallets.

Cylinders containing compressed gases

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Cylinders containing compressed gas may only be stored in open and they are to be protected against excessive variation of temperature, direct rays of sun, or continuous dampness. Such cylinders shall never be Stored near highly flammable substances, furnaces or hot processes. The room where such cylinders are stored shall have adequate ventilation.

General guidelines
 When stacking material, be sure that the stacks are not over balanced or lopsided and the foundation is level and solid  Gloves must be worn when handling rough materials, such as barrels, drums; steel, boxes, brick, etc.  All operating personnel must wear safety shoes. These may be obtained btock in charge and the safety section.  Two wheeled hand trucks should be pushed, not pulled, in Order to avoid catching

the heel of the operator. Only four wheeled trucks with swivel axles and long tongue handles are safe to be pulled.  Drive ways, platforms, walks, stairways or ladders must not be obstructed with

any materials, such as ropes, lines or supplies.  be removed.  feet.  LEGS.  Remover cut off, or hammers down protruding nails, staples or steel ship in To up-end drums, stand dose to end, place feet slightly apart, grip underside In moving drums, wear gloves and grip chimes on top, never roll drums with At the completion of a job all scaffolds, ladders, materials, scraps, tools, etc. must

of drum end with hands about eight inches apart. BEND KNEES AND LEFT WITH YOUR

boxes or barrels before you reach site.

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