Chapter 1 Q) Explain the requirement for layout of hazardous chemical plant? Which statutory requirement is to be completed? OR Q) Write down the criteria for sitting & Layout of chemical plant? STATUTORY REQUIREMENT Planning AND layout are as per required u/s 6 of the Factories Act 1948 and. u/r 3 & 3A of the Maharashtra Factories Rules 1963. SITING CRITERIA 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
Land availability and its cost. Raw material availability. Labour availability. Infrastructure availability. Access to market. Transport facilities. Drinking and process water facilities. Sewage and Drainage. Place for solid and liquid waste disposal. Interlinking with other plants. Surrounding population density and distance from the public. Distance from highway and railway and from transport centres. Suitability of climate, environment and factors related to ecology, geology,
14.
meteorology, micro & macro biology. Government policy advantages like subsidies, incentives and zoning (area
15.
reservation e.g. SEZ) if prescribed. Other techno-economic criteria.
Some General Principles for good Layout are1.
Enough work space (2 m2 per 'person) should be provided for workers to work
2.
without restriction. Proper roads, walkways, tracks, alleys, catwalks etc. should be provided for free
3.
passage of men and materials to avoid delay and obstruction. Sufficient doors, windows, ventilators and open space must be provided for good
4.
ventilation and lighting. Installation of machinery, floors, stairs, lifting machines, electric wiring etc. must be done to ensure safety
5.
Keep the handling of materials to the minimum. Use mechanical means to reduce
6. 7. 8. 9.
manual strain. Provide safe means of access to all work places. Provide safe transport facilities for men and materials. Provide adequate emergency exits. Purchase and arrange in orderly manner machines and equipment with built-in
10.
safety. Isolate high noise, vibration, fire, explosion and toxic hazards. Design a work bench, table, booth, roof, ladder, platform, sheet, support etc. with safety
11. 12.
standards to avoid such hazards. Allow space for future expansion. Provide repair and maintenance workshop, welfare facilities and education and
13. 14.
training facilities. Use appropriate colours, notices, signs, labels, posters etc. for safety. Provide easy locations of fire alarms, fire fighting equipment, personal protective
15.
equipment, emergency assembly points, medical centre, safety office etc. Provide and maintain good housekeeping.
Other factors of plant layout and design from safety point of view are: 1.
Safe design and construction using safety standards and good engineering
2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14.
practices. Statutory requirements for plant layout and design. Containment of leakage and accidents. Segregation of different risks. Safe storage, process, utilities and waste disposal design. Safe control room location & design. Emergency control devices. Fire fighting and gas leak control facilities. Ample water storage. Auto controls, alarms, trips, interlocks and necessary safety devices. Railings and guarding at chances of fall cross over and on moving machinery. Roads of sufficient width and signs. Safe loading, unloading, transport and piping facilities. Security round the clock. Wind direction and speed indicator with recorder to know wind direction and
15.
speed. First aid centre and ambulance van.
Q) Plant area classification? Significance of plant area classification? In chemical, petrochemical, refinery and fertiliser factories and also in coal mines, combustible/explosive dust, vapour and gases may evolve during normal or abnormal operating condition IS'.5572 divides the hazardous area (containing flammable gas or vapour capable to be ignited) into following three zones
Zone 0 Areas: Here hazardous atmosphere exists continuously viz., the vapour space of closed process vessels, storage tanks or closed containers. Any spark will certainly lead to fire or explosion. Zone 1 Areas: Here hazardous atmosphere is likely to exist at any time. Therefore the fullest practicable measures should be applied to prevent a hazardous condition at any time and in any circumstances. Zone 2 Areas: Here hazardous atmosphere is likely to occur only under abnormal operating conditions. This classification is applicable only where a fire or explosion hazard is unlikely and may be caused only by the simultaneous and improbable occurrence of an arc or spark resulting from an electrical failure and a hazardous atmosphere arising through failure of the conditions of control. Significance1.
It helps to determine frequency and duration of the occurrence of an explosive
2.
atmosphere. To identify places where, because of the potential for an explosive atmosphere, special precautions over sources of ignition are needed to prevent fires and
3. 4. 5. 6.
explosions. To identify special precautions to protect the health and safety of workers To identify the hazardous properties of the dangerous substances involved To identify the amount of dangerous substances involved To identify the work processes, and their interactions, including any cleaning,
7.
repair or maintenance activities that will be carried out To identify the temperatures and pressures at which the dangerous substances
8.
will be handled;. Provide the information for Ventilation, either natural, or mechanically (e.g. produced by fans), can both dilute sources of release, and remove dangerous
9. 10.
substances from an enclosed area. To identify equipment suitable for a specific location. Following three zones for the purpose of appropriate electrical installation.
Q) UN Classification of hazardous chemical? The hazardous chemicals/dangerous goods are divided by the United Nation Committee of Experts on the Transport of dangerous goods into the following classes: CLASS 1
:
Explosives
Division 1
Substances and articles which have a mass explosion hazard.
Division 2
Substances and articles which have a projection hazards but not a mass explosion hazards. (Example-Ammonia nitrate, ammonia picrate)
Division 3
Substances and articles which have a fire hazard and either a minor blast hazard or a major projection hazard or both, but not a mass explosion hazard. (Example-Missile, Rocket)
Division 4
Substances and articles which present no significant hazard. (Example- hand granites)
Division 5
Very insensitive substances which have a mass explosion hazard.
CLASS 2
Gases compressed, liquefied, dissolved under pressure or deeply refrigerated.
Division 2.1
Flammable gases (Example-Hydrogen, LPG)
Division 2.2
Non flammable gases (Example-Fluorine, Nitrogen)
Division 2.2
Toxic gases (Example-Sulphur dioxide, Carbon monoxide)
CLASS 3
Inflammable liquids.
Division 3.1
Less flammable (Example- Thinner, paints)
Division 3.2
Highly flammable (Example-Petrol)
CLASS 4
Inflammable liquid
Division 4.1
self-reactive (Example-Sulphur)
Division 4.2
Substances liable to spontaneous combustion. (Example-yellow Phosphorus, activated carbon)
Division 4.3
Substances which on contact with water, emit inflammable gases. (ExampleSodium, potassium)
CLASS 5
Oxidising substances; organic peroxides.
Division 5.1
Oxidising substances. (Example- potassium permagnet, H2O2)
Division 5.2
Organic peroxides. (Example-benzoyl peroxide)
CLASS 6
Poisonous (toxic) and Infectious substances.
Division 6.1
Poisonous (toxic) substances. (Example-Cyanide)
Division 6.2
Infectious substances. (Virus, bacteria, parasite)
CLASS 7
radioactive substances (Example- Uranium, Radium)
CLASS 8
Corrosives. (Example- Hydrofluoric acid, sulphuric acid)
CLASS 9
miscellaneous dangerous substances.
Q) Describe the importance of instrumentation of safe plant operation? After understanding various types of chemical hazards in foregoing parts, we should proceed to know the instruments, equipment and other control measures. To maintain, control, measure, alarm and record process parameters, various industrial instruments and safety devices are used. Some instrument and there importance as follow-
Basic Instruments Name Anemometer
Importance Instrument for measuring the speed of wind
Atmometer
or any other moving gas. Evaporimeter. An instrument for measuring
Barometer Calorimeter
the rate of evaporation of water. For measuring atmospheric pressure. For determining quantities of heat evolved,
Hygrometer
absorbed or transferred. For measuring the relative humidity of the
Manometer
atmosphere. For measuring gaseous pressure.
Specific Instruments Gas/Fume/Vapour Detector & Alarm
Give warning when pre-set air-gas (toxic or explosive) mixture exceeds the set TLV or LEL/UEL limit. It detects flue gases, LPG, smoke,
petrol
hydrocarbons, Metal Detector
vapours,
paraffin
fumes,
ammonia,
Freon,
hexane,
acetone, benzene, chloroform fumes, It detects the metallic objects of ferrous and non-ferrous
materials
hidden
in
the
pocket/bag etc. and can locate the concealed Electronic Flasher
conducts or cables etc., A built-in solid state electronic flasher which can flash mains bulb or series lamps on
Electronic Air Cleaner :
mains at adjustable flashing rate. It deactivates dust particles suspended in air, reduces effects of secondary smoking and controls virus and retards growth of bacteria.
Alcohol Detecting Instruments
With electronic alarm to warn before drivers sit behind the wheels or workers on the machines, thus prevent them from alcohol consumption when they are on duty.
Chapter 2 Q) Describe hazards and safety measure in fertiliser industry? Hazards 1. 2. 3. 4.
In the warehousing stage, phosphate. Potassium-salt and other dusts are released. Toxic gases (Fluorine compounds, H2SO4, NO, HCI, CO and NH3, gases) and dust, High air temperature and noise are noticed. In finishing processes, weighing, bagging and storing, gaseous emissions and
5.
fluorine compounds are released. Phosphates and other raw materials contain 10% or more free silica which may
6. 7. 8. 9. 10.
cause pneumoconiosis. The dust of soluble fertilisers causes irritation. Ammonia gas leakage Poor lighting and illumination Poor housekeeping Material handling
The safety measures include: 1. Mechanisation and automation of production processes, provision of remote control, careful assembly and safe operation of equipment and heat insulation. 2. Process segregation and walls and floor covering to absorb fluorine compounds. 3. General ventilation, exhaust ventilation of enclosed plant, cleaning of exhaust air and waste water. 4. Safety measure for ammonia storage plant, CO detection and alarm. 5. Safety from synthesis gas and ammonia, 6. Keep the handling of materials to the minimum. Use mechanical means to reduce manual strain. 7. Education and personal hygiene. 8. Use of PPF and safety showers. 9. Safety and sanitary supervision. 10. Pre and post medical examination including radiographs of the loco motor system and lungs. Q) Describe hazards and safety measure in petrochemical industry? Hazards
1. 2. 3. 4. 5. 6. 7.
Fire & explosion Physical Hazard- Heat, noise, dust Electric Hazards- Electricity & Static Electricity Hot Works Sparks from vehicle Hot line/ furnaces Realised of toxic gases
Safety Measures in Petroleum Refinery _ 1. 2.
H2S generation should be used to get pure sulphur. Hydrocarbon vapours should be controlled by floating roof tanks, double
3.
mechanical seal and leak detectors. Safety distance should be maintained as per OISD, CCE and TAC norms.
4. 5.
Petroleum Act and Rules should be implemented: Computerized system to prevent overflow, over filling and leakages. Automatic detection and alarm systems for flammable and toxic gases throughout
6. 7. 8. 9. 10.
the plant. Deluge water spray system on tanks, pumps, critical vessels, air coolers etc. Aviation lights on all tall structures. Explosion proof control rooms. Use of HAZOP studies from design to operation stage. Zero effluent discharge and minimization of SOx, NOx, CO, H2S, NH2 and un-
11.
burnt carbon discharges. Efficient dust control measures for dusts of coal, coke, sulphur and other
12. 13.
materials. Efficient communication and fire fighting systems throughout the plant. On-sight and off-sight Emergency plans, SOPs, work permits, safety audits, risk assessment and control measures, safety policy, safety committee, medical examinations of workers, safety training and use of necessary PPE are all essential.
Q) Describe the safety measure that is to be adopted in chloro alkali plant? In the chlor-alkali plant 1.
In the chlor-alkali plant, safety measures refer in particular to the prevention of liquid chlorine spillage, using means such as: - overfilling protection systems - correct choice of construction material and regular inspection of vessels - Bonding for vessels containing hazardous material and also:
2. 3.
Preventing impurities to avoid any explosive mixture. Measuring and control of hydrogen concentration in the chlorine gas from the cell room and after each liquefaction step, and measuring and prevention of possible
4.
NCl3 accumulation. Prevention of failure of the electrical supply.
5.
Emergency generators for supply of power to vital equipment when/if grid power
6.
fails and also the prevention of failure of the instrument air supply. Prevention of chlorine releases by a collection of chlorine releases during
7.
maintenance operation to the absorption unit. The use of pneumatic valves with automatic shut down in case of failure of the
8.
link, at both ends of the link, is essential to limit the leak. Good pipe work design to minimise the length of pipeline containing liquid
9. 10.
chlorine Limitation of the overall liquid chlorine inventory to what is really needed. A simplified layout and a reduction in the number of valves, pipes and
11.
connections reduce the risk of leakage Improved chlorine detection and location and rapid isolation of sources feeding a
12. 13. 14. 15.
leak High-pressure alarms on stock tanks Two independent level/weight alarms on receiving tank Relief valves at appropriate settings and permanent monitoring of the installations under the responsibility of a designated
16.
person specially trained for chlorine hazards good compliance with safety parameters defined in the safety report, including
17.
periodic inspection and control of materials specified according to safety hazards maintenance programmes for the installations: for example, storage, maintenance of pipe work, pumps, compressors, monitoring of moisture
18. 19. 20.
concentrations, impurities in liquid chlorine Training of personnel Periodic mock drill exercise carried out. Pre medical and periodic medical examination of worker.
Q) Explain the process description and major accident hazards control adopted in DAP Manufacturing plant? Details of DAP Manufacturing Process 1. 2. 3.
Rock Phosphate, the raw material use for making phosphoric acid. Rock Phosphate is treated with sulphuric acid to form phosphoric acid. Phosphoric acid is then mixed with Ammonia, Furnace Oil, Sand & Sulphuric acid to form DAP.
Control measure adopted in DAP Manufacturing plant Environmental issues associated with phosphate fertilizer plants include the following: ¡ 1. 2. 3. 4. 5.
Air Emissions Wastewater Hazardous materials Wastes Noise
Air emission- Process emissions include gaseous fluorides in the form of hydrofluoric acid (HF) and silicon tetrafluoride (SiF4) Control measure 1.
Properly select the phosphate rock to minimize the amount of acid required in the wet production process, reduce emissions into the environment and increase
2. 3. 4. 5.
the possibility of phosphor gypsum reuse Select proper size of screens and mills (e.g. roller or chain mills) Use covered conveyor belts and indoor storage Apply good housekeeping measures ( Recover dust from phosphate rock grinding through use of properly operated and
6. 7. 8. 9.
maintained fabric filters, ceramic filters, and / or cyclones; Treat gaseous fluoride emissions using scrubbing systems Reduce aerosol emission by installing cyclones and scrubbers Reduce fluorides emissions by recycling of warm air. Installation of leak detection and continuous monitoring in all sensitive areas
Waste water- Emissions to water for the disposal of gypsum may contain a considerable amount of impurities, such as phosphorus and fluorine compounds, cadmium and other heavy metals Control measure 1. 2. 3.
Select phosphate rock with low levels of impurities Recycle water used for the transport of phosphor gypsum back into the process Where available, consideration should be given to use seawater
Noise - Noise is generated from large rotating machines, including compressors and turbines, pumps, electric motors, air coolers, rotating drum. 1. 2. 3. 4. 5.
Selecting equipment with lower sound power levels Installing silencers for fans Installing suitable mufflers on engine exhausts and compressor components Installing acoustic enclosures for equipment casing radiating noise Improving the acoustic performance of constructed buildings, apply sound insulation
General Safety measure 1. 2. 3.
Training of personnel Periodic mock drill exercise carried out. Pre medical and periodic medical examination of worker. Training of
4.
personnel Use appropriate PPE.
Q) Explain the unit process and unit operation? OR Define unit process and unit operation with example? OR Hazards in unit process/operation? Unit Process In such processes, by combination (chemical reaction) of two or more chemicals, a new product (compound) is formed. It indicates a chemical change. 1.
Alcoholic Caustic Fusion: Reaction carried out a lower temperature (1051300C) using caustic soda o) potash and alcohol (like ethanol, methanol,
2.
cellosolve, isobutanol). Amination: Introduction of amino group in the molecule using liquid ammonia or
3.
any other amination agent. Caustic Fusion: Reaction carried out in molten caustic potash/caustic soda at
4.
temperature above 1500C. Condensation: Reaction in which two or more molecules combine with the
5.
separation of water or simple substance. Halogenation: Introduction of chlorine or bromine in the molecule using calcium
6.
hydroxide etc. Hydroxylation: Introduction of hydroxyl group in the molecule using calcium
7.
hydroxide etc. Nitration: Introduction of nitro group in the molecule using nitric acid or mixed
8.
acid. Oxidation: Introduction of oxygen or removal of hydrogen from the molecule
9.
using oxygen liberated by the action of acid and substance rich in oxygen. Reduction: Introduction of hydrogen or removal of oxygen from the molecule
10.
using hydrogen liberated by the action of acid and metal. Sulphonation: Introduction of sulpha group in the. Molecule using sulphuric acid or oleum or chlorosulphonic acid.
Unit Operation In such operations, there is no chemical reaction to form a new product. It indicates no chemical change but mechanical or physical change like distillation, cutting, heating, cooling, drying, mixing, grinding, washing, packing, transferring, filtering, handling, radiation etc. Some general operations in a sequence are as follows 1.
Steam distillation: Live steam is passed in the still to recover the solvent. Vapours of solvent and water are passed in a shell-tube type condenser and
cooler. Then the cooled distillate are taken in a separator where solvent and 2.
water separate out and are diverted to respective storage. Heating: Heating operation can be done either directly or indirectly. In direct heating, steam is passed in the material directly to heat the material. In indirect heating, heating media (e.g. steam, hot oil, hot flue gases etc.) are passed in
3.
jacket / coil of the vessel. Cooling: It can be done directly or indirectly. In direct cooling, ice or cooled water is added to the material directly. In indirect cooling, cooling media (raw water, chilled brine, cold oil etc.) are passed in jacket / coil of the vessel.
4.
Drowning means transferring reaction mass from the reaction vessel to a tank
5.
which is containing water or other medium (e.g. dilute acid, dilute alkali etc.) Pulverisation: This operation is done to reduce size of the material. Usually
6.
crushers, pulverises, ST Mill are used. Blending: This operation is done in a blender to mix thoroughly two or more
7.
dried products. Washing: This operation is done in presses, nutches or centrifuge to remove
8.
soluble impurities and acid/alkali from the product. Packing is filling up of finished product in the containers.
Hazards associated with unit processes/ operations are: 1. 2. 3.
Mechanical hazards e.g. pressure release, leaks, burns, noise, . Equipment or utility failure. Reaction hazards due to failure to control isotherms, incompatible materials, side
4. 5. 6. 7.
reactions, feed ratio or rate variation etc. Environmental hazards such as air pollution, odour problems, spills etc. Toxicity and health effects Flammability hazards due to explosive mixture, static charge, auto ignition etc. Radiation hazards.
Q) Sampling of toxic and flammable substance in Chemical industry? OR Describe sampling technique for petrochemical? Types of Sampling: They are (1) Personal sampling (2) Area sampling (3) Grab sampling and (4) Integrated sampling. In personal sampling1.
The sampling device is worn by the worker near his breathing zone to evaluate personal or individual exposure to him.
2.
The measurement device (head) or dosimeter is kept in the breathing zone by attaching it to the collar. To monitor noise, the device should be placed close to the ear.
In area sampling – 1.
The air samples are taken at fixed places in a workroom or confined spaces to evaluate general concentrations of flammable, explosive or toxic material in air for
2.
the purpose of isolation or restriction to work or to design the control measures. It includes continuous monitors for leak detection, ventilation failure, equipment malfunction etc.
Grab sampling 1.
It is used to measure concentration at a particular time e.g. peak value of NH 3 or Cl2
2.
at a particular time. The sample is collected in evacuated flask or plastic bag, sealed and sent to a laboratory where trace analysis is carried out by gas chromatography,
Integrated air sampling 1.
It is carried out by direct reading instruments (e.g. gas detector tubes or digital
2.
meters) to measure STEL value for 15 minutes and TLV for 8 hr TWA limits. An air-sampling train consisting of air-inlet orifice, collection media (solid or liquid sorbent, filters and passive monitors), air-flow meter, flow-rate control valve and suction pump, is used by qualified and trained personnel. Direct-reading gas and vapour monitors include (1) Colorimetric devices - stain
3.
tubes and hand or battery operated pump (2) Colorimetric paper tape samplers (3) Electrical instruments (4) 0 monitors (4) CO monitors and (5) IR analysers. Chapter 7 Q) How will you transfer chemical by pipeline in chemical industry? First of all to transfer chemical from pipeline following point need to be consider as safety point of view1. Material of construction is selected depending on nature (corrosivity, toxicity, flammability etc.), quantity (weight, flow, pressure) and other parameters like temperature, viscosity, colour, expansion etc. 2. For extremely hazardous chemicals, pipes are tested for inter granular corrosion and certified before used. 3. Minimise pipe length, branches and joints, and flanges on vacuum lines.
4. 5. 6. 7. 8.
Provide welding joints for highly flammable or toxic chemical good gaskets and gland packing, flange guard to deflect leak downward, Bellows subjected to axial movement. adequate pipe supports, walkways, platforms or working place, Earthing and bonding to remove static charge due to flow, overflow return from
measuring vessel to a storage tanks. 9. painting with colour coding (IS:2379) for Identification of pipelines is necessary to avoid any mistake while operating any valve, taking connection or opening the line for repair c maintenance. 10. Cathodic protection where required. 11. More pipe work in dyke is not desirable, particularly with hazardous chemical, as it may be trapped in fire in the dyke. 12. Similarly pipelines of flammable or toxic chemical should not be laid in tunnel, as its leak may spread from one area to another. 13. Electric cables or hot lines and flammable gas or liquid lines should not run side by side. 14. Piping arrangement should be such that in case of failure at any point, the system can be quickly isolated by closing valves, without disturbing the rest of the system. 15. Flushing arrangement should be provided for easy start up and maintenance. Pipe 16. To allow for thermal expansion special joints or loops should be provided. 17. Emergency control valves should be easily accessible. 18. By-pass valves should be within easy reach. 19. Auto control valve should have bypass or manual valve which may be required in the event of failure of auto control valve. 20. Pressure relief device, liquid seal, manual vent valve etc. should be provided to depressurise the system where necessary. 21. Flexible pipes, joints and hoses should be safe, sound and properly tested 22. Semi-conductive material for hoses preferred over non-conductive or good conductive material to avoid static electricity. 23. In above ground pipe work which remains isolated during normal operations, thermal relief system should be provided to protect against increasing ambient temperature. Q)
Describe brief the colour coding of pipeline and the importance in chemical
industry? OR Colour coding and its needs? Colour Coding: 1. The piping in a Chemical plant may carry harmless or hazardous contents. Therefore it is highly desirable to identify them. Some standard colour coding is as follows: Content in the piping Flammable or water for fire protection Dangerous (hazardous chemical) Safe (water, air) Protective material (inert gas)
Colour Red Yellow Green Blue
2. The proper colour may be applied to the entire length of the pipe or in bands 20-25 cm wide near valves, pumps and at repeated intervals along the line. 3. The name of the specific material should be stencilled in black at readily visible locations such as valves and pumps. 4. Anti-resistant colours should be used where acids and other chemicals may affect the paints. 5. Entire length or a portion, more than 30 cm, of a pipeline should be painted so that it should not be mistaken for a colour band. 6. The colour bands are superimposed on the ground colour, applied at start, near valves, joints, bends and end points. 7. Following colour coding is also useful in identifying pipelines (IS:2379): Sr No 1. 2. 3. 4. 5. 6. 7. 8.
Material Water Steam Air Acids Alkalis Gases Hydrocarbons/ organic compounds Mineral, vegetable and animal oils, combustible
Colour Sea green Aluminum,IS 2339 Sky blue Dark violet Smoke grey Canary Yellow Dark admiralty grey Light Brown
9.
liquids. Other liquids / gases which do not need identification
Black
Significance of colour coding 1. Colour coding (IS: 2379) for Identification of pipelines is necessary to avoid any mistake while operating any valve, taking connection or opening the line for repair c maintenance. 2. To identify the harmless or hazardous contents carrying through pipline 3. The colour and lighting influence vision and contribute to ' the wellbeing, morale, attitudes, housekeeping, quality, productivity, health and safety. In industry colours are used to 1. Improve lighting conditions. 2. Decorate the environment. 3. Increase efficiency and productivity. 4. Improve quality of workmanship and normal skill. 5. Improve labour morale and interest in work. 6. Reduce accidents and increase safety. 7. Reduce absenteeism. 8. Raise standard of good housekeeping. 9. Improve building and machinery maintenance. 10. Reduce hidden costs of dull and gloomy atmosphere, and 11. Improve overall psychological and physiological effects on workers for better work performance.
What is man by confined space and its hazards Safety precaution required during working in confined space? 'Confined space' as any space by reason of its construction as well as in relation to the nature of the work carried therein and where hazards to the persons entering into working inside exist or are likely to develop during working. Example- Work in vessels and tanks below ground in pits, cellars and basements or inside confined spaces such as silos, tanks, vats, vessels, boilers gutter etc. Hazards of Confined Space can be classified as1. 2. 3. 4. 5. 6. 7. 8.
Poor lighting and ventilation. Oxygen deficiency. Contamination of toxic and/or flammable gases. Unexpected activation of machinery or flow. No way or no time available for exit. Engulfment (burying) in loose material. Non specific work practices. Other hazards are suffocation, burning, poisoning, explosion, drowning, freezing, crushing, entrapment, scalding, stroke, heat stress, radiation, physical trauma, injury by moving machinery, slipping or falling etc.
Control Measure 1. Tanks, vats, pits, sumps, vessels, floor opening etc. should be protected by guard rails or cover. 2. Fixed ladder with handrail if possible, should be provided to step down safely. 3. Portable (rope) ladder may be used while working inside a tank or vessel for temporary work. 4. Check the concentration of toxic or flammable gas, dust, vapour etc., by a gas detector. Oxygen content should also be checked for safe proportion. It should be >18%. 5. Air line or self contained breathing apparatus and safety belt are essential. 6. Sump pumps with flameproof electric or pneumatic motors and air extraction fans (spark proof) and exhaust ducting to remove heavy vapours is necessary. 7. Complete isolation of the vessel, cleaning, purging and ventilation of the vessel, inspection and testing, safety permit and all rescue arrangements must be done before such work and only a trained worker will work under constant help and supervision. 8. Latest safety and rescue systems should be used. Winch arrangement connected with the worker's harness is useful to lower and pull out quickly.
9. Hand free communication system is available to keep the worker in the tank in constant touch with the supervisor outside. Hand operated clutch, cord and chair assembly can be used to lower the person while working at height or depth. 10. Bottom drain valve and other nozzles should be kept open to allow good ventilation and fresh air in a vessel or tank. 11. Wear helmet or hard hat, safety shoes and protective clothing necessary. Q) Write in detail the safe procedure for start up and shut down? Safe Start-up procedure 1. Starting sequence should be well defined, written and known to the workers involved in this work. 2. Starting in sequence of utilities like water, air, power; purging, charging, slow and gradual heating, monitoring of pressure, temperature, flow and reaction rate, cooling if necessary, starting of exhaust system, scrubber or condenser etc., observing noise, vibration, speed, alignment, synchronising etc. are all important. 3. During start-up check Ensure Housekeeping, No scrap material should be left over after completion
of work which may result in obstruction in the workplace leading to hazards Ensure the availability of Raw material and utility Check the instrument by Trial run which handed over by maintenance
department for safe operation function and direction Before receiving of Raw material check the Tank level Checking earthing bonding and insulation Ensure the removal of debris Ensure the purity of chemical Ensure the alarm system as per the requirement. Start up the operation as per given in manual. Ensure the quality of final product and its supply Ensure the plant running in specific capacity Ensure the quality of catalyst Check the leakages
4. Correct identification of pipelines, valves and gauges, correct sequence of control operation, correct charging or addition-rate and instead of relying on instruments only Counter-check of other parameters and strict manual observation and satisfaction are requisite precautions for safe start-up procedure. 5. Other points needing attention in start-up are removal of shutdown blinds, providing running blinds, opening of scrubber or discharge line valve, opening of isolation valve before safety valve, starting of local exhaust ventilation, pump cooling and priming, readiness of fire fighting equipment, leak detection etc
Safe Shutdown Procedure
Stoppage of all the process in the plant Empty out all the tanks, vessels in the process and in the storage area Preparation of equipment like Welding M/c, Grinding, Cutting tool, lectric supply. Stoppage of incoming utility Flushing and washing of the container Gas testing inside the container for toxic gases Checking for oxygen deficiency Used appropriate PPE Procedure, Norm, Work permit system should be followed Action in case of emergency potential hazards like first aid, assembly point, wind
direction socks. Fire fighting equipment must be keep ready. Testing of safety valve, pressure vessels, temperature, rupture disc RTD Get clearance certificate from all the concern department Follow the sequence of operation Good housekeeping is also must
Chapter 3-4-5-8 Health Hazards while handling Chlorine? 1. Chlorine is corrosive. It can burn moist body surfaces such as the eyes, nose, throat, lungs, and wet skin because it forms harmful acids when it reacts with moisture. 2. Repeated exposure to chlorine does not produce an immunity or tolerance. 3. Long-term exposure to low concentrations of chlorine may cause a gradual decrease 4. 5. 6. 7. 8. 9.
in lung efficiency. Can cause life-threatening accumulation of fluid in the lungs (pulmonary edema). Coughing, shortness of breath, difficult breathing and tightness in the chest. Exposure to a high concentration can cause a long-lasting condition like asthma. The skin may become waxy white or yellow. Blistering, tissue death and infection may develop in severe cases Direct contact with the liquefied gas can freeze the eye. Permanent eye damage or
blindness can result. 10. May harm the respiratory system. What are the safety precautions for the bulk storage of ammonia? 1. In case of multiple storage facilities, a plan should be prepared for readily and definitely approaching all shutoff valves to be used for isolating various parts of the storage facilities. 2. Each storage area should be protected at least by one standard fire hydrant. 3. Gauge of glass should be provided with excess flow check valves. The Gauge glasses should not be longer than 120 cm and more than 60 cm between supports.
4. Storage tank construction should be of integrity and double wall type known as 'can in tank' type. 5. Each storage tank shall be equipped with two relief valves mounted on a 3-way hand valve to provide means for repair of faulty valve. 6. Install remote controlled valves at the bottom of ammonia storage tank. 7. Facilities for creating water curtains around the ammonia storage tanks should be created to absorb
ammonia vapours if they leak .out, however, care should be
taken not to add water to the liquid ammonia else it will worsen the situation. 8. Non refrigerated ammonia shall be stored in gas tight containers. 9. In the event of power failure, provision should be made to run the holding compressors of all the ammonia storage by emergency diesel generating sets so as to compress excess vapour into liquid ammonia (for refrigerated bulk storage system ) 10. A flare stack should be provided to burr ammonia vapour in case safety valve fails to release ammonia pressure. 11. Trained first-aiders having the knowledge in the use of first aid equipment. 12. Provide necessary showers, eye-baths and oxygen administration apparatus 13. Provide adequate-and suitable personal protective equipment at all times e.g. gastight chemical goggles, self contained breathing apparatus, positive pressure hose masks, air line masks, chemical cartridge respirators, hard hats, soft-brimmed hats or caps, safety-toed rubber boots, rubber gloves, rubber apron or rubber coat, sleeves and trousers legs, etc. 14. Use large volumes of water directing on leak. 15. Leaks of an ammonia should be searched for, preferably with Hydrochloric acid solution or with a small cylinder of the compressed SO, gas. Q) What are the precaution to be taken while transportation of hazardous material? 1. Every owner shall display on goods carriage and on every package mark of class label 2. If the package represents two hazards, two labels shall be displayed on the package. 3. Such goods carriage shall carry safety equipment to prevent fire, explosion or escape of hazardous goods and shall be fitted 4. The tank carrying hazardous material cars should be properly designed and fabricated to meet the service condition. 5. Vent valves and arrangements to prevent static electricity build up when handling solvent, are a must. 6. Positioning of the hazardous chemicals away from the locomotive 7. Proper labelling of content and the hazardous nature of the chemicals. 8. Goods carriage carrying dangerous or hazardous goods to human life, shall be fitted with a spark arrester. 9. Every consignor shall supply to the owner of the goods carriage accurate and sufficient information about the hazardous goods so as to enable such owner and his driver to comply with and be aware of the risk to the health or safety of any person.
10. Valid registration to carry hazardous goods listed first aid, safety equipment, antidote; training to driver to control transport emergency are also necessary. 11. Driver 'shall observe at all times all the precautions to prevent fire, explosion or escape o hazardous goods, shall ensure parking in a safe place and under control and supervision of himself or some other competent person 12. Tramcard should be given to workers. The content of a 'Trerncard' should include name of cargo (material), nature of its hazard, protective devices including PPE and emergency action to (1) inform Police and Fire Brigade (2) Spill or gas control (3) Fire control and (4) First aid. 13. The transporter should carry 'Emergency kit' containing tool kit, emergency lighting, fire extinguisher, protective clothing, breathing equipment and first-aid kit 14. Proper training to drivers of hazardous chemicals is legally required. Safety checklist or transport vehicles shall be prepared and used. 15. The driver transporting any hazardous goods shall forthwith report any accident involving such goods to the nearest police station and also the owner of the goods carriage or the transporter. Define following Term Flammable substance Flammable substances are those gases, liquids and solids that will ignite and continue to burn in air if exposed to a source of ignition. Many flammable and combustible liquids and solids are volatile in nature; that is, they evaporate quickly and are continually giving off vapours. The rate of evaporation varies greatly from one liquid to another and increases with temperature. It is their vapours combined with air, not the liquid or solids themselves, that ignite and burn. In many instances, an increase in temperature creates a more hazardous condition because of the increase in the rate at which vapours are evolved Toxic substance Substances as defined in clause (i), Schedule 19 on Chemical Works u/r 102 of the Gujarat Factories Rules, mean those substances which cause fatality or serious health effect and which exceed their TLV specified in the 2nd Schedule of the Factories Act Explosive
An explosive material, also called an explosive, is a reactive substance that contains a great amount of potential energy that can produce anexplosion if released suddenly, usually accompanied by the production of light, heat, sound, and pressure. Dust Solid particles generated by handling, crushing, grinding, rapid impact, detonation of organic or inorganic materials such as rocks, ore, metal, coal, wood, grain etc. Dusts do not tend to flocculate except under electrostatic forces. They do not diffuse in air but settle under the influence of gravity. The particle size varies from O.I to 1000 microns. Fly ash from chimneys varies from. 3 to 80 microns. Describe safe storage, safe transportation, safe handling of hazardous chemical? Safe Storage 1. Storage tanks of dangerous chemicals must be constructed and controlled properly. 2. Safe inventory must be maintained. Content should be minimum possible. 3. Necessary safety fittings on the tanks should be provided. 4. LPG tanks and tanks of other flammable or toxic chemicals must have proper safety devices. 5. Toxic gases should be kept in liquefied state if possible. Cooling media and device, safety valves, pressure gauges, temperature-gauge, scrubber, level or content indicator, flare, water curtain, toxic exposure sensors and alarms, emergency bypass, 6. 7. 8. 9.
safe discharge and collection, etc. should be provided as per requirement. Name and quantity must be clearly mentioned to assess the hazard potential. Barrels, carboys, glass vessels must be kept, handled and used in safe manners. Use emergency kits, tools etc. where necessary. All the vents of storage ranks of low boiling chemicals should be connected to an
appropriate 10. Condenser or scrubber, Alternate power must be kept ready to run the cooling system, scrubber etc., in case the main power fails. Safe Handling (Liquid, solvent, gas) 1. Before handling, containers should be carefully inspected and damaged or leaky containers, if any, be segregated. 2. Containers should not be dropped, rolled or so handled as to risk damage to them. 3. Good housekeeping standards are-essential in storage areas 4. Such areas should be isolated by distance or constructions so that they do not expose important buildings to fire 5. Rooms to be well ventilated to safe guard against fire and explosion hazards as also against health hazards
6. Provision should be made for automatic sprinkler protection and all potential sources of ignition should be eliminated. 7. While transferring solvent, earthing and bonding of metal tanks and containers are necessary 8. Inert gas blanketing of vessels and flameproof electrical fitting and apparatus are essential 9. Solvent which can generate explosive peroxide upon exposure to air and light hence it should be stored in dark place 10. Adequate personal protective equipment should be provided. 11. Emergency shower and eye washer should be provided. 12. Training of personnel necessary. 13. Avoid mixing of chemicals. Take full precautions. . 14. Routine thorough check-up procedures. ****For Safe transportation SEE above**** What are the hazards present in the process and operation involving toxic substance and their precaution? Hazards associated with processes/ operations of toxic substance are: 1. 2. 3.
Mechanical hazards e.g. pressure release, leaks, burns, noise, Equipment or utility failure. Reaction hazards due to failure to control exotherms, incompatible materials, side
4. 5. 6. 7. 8. 9. 10. 11. 12. 13.
reactions, feed ratio or rate variation etc. Environmental hazards such as air pollution, odour problems, spills etc. Toxicity and health effects Flammability hazards due to explosive mixture, static charge, auto ignition etc. Radiation hazards health hazards (such as irritation, sensitization, and carcinogenicity) Physical hazards (such as flammability, corrosion, and reactivity). Fire and explosion Contact with other chemical Splashing of hot, corrosive or toxic liquid Pressure, temperature, flow, quantity, and other parameter creates process
14. 15.
hazards. The vessels and chemical in which toxic substance are stored Leak, spill, and splashes causes handling hazards
Control measure 1. 2. 3. 4. 5. 6.
Adequate personal protective equipment should be provided. Emergency shower and eye washer should be provided. Ensure that sufficient space is available in the receiving tank. Training of personnel necessary. Avoid mixing of chemicals. Take full precautions. . Routine thorough check-up procedures.
7. Vessel containing toxic substance should be sound construction of material. 8. Fir fighting equipment must be kept ready and placed at accessible area 9. Suitable posters showing dangerous properties of these chemicals and safe working procedure should be prominently displayed. 10. Suitable scrubbers, absorbers or neutralisers for inorganic gas or vapour and condenser for organic vapour should be provided and well maintained. 11. the reactor should have safety valve to take care of any pressure built-up due to closer of the scrubber line valve or any choking 12. Leak detector with alarm, ventilation according to the vapour density of the material, open working space, local exhaust ventilation on toxic (e.g. pesticide) fumes 13. Interlocks, trips and alarms, auto controllers, automatic process correction device, computer controls, DCS system, direct reading, display and correction system etc. should be provided as per process requirement. 14. While transferring toxic substances, earthing and bonding of metal tanks and containers are necessary 15. For handling poisonous gases such as chlorine, ammonia, sulphur dioxide, phosgene, phosphine etc., workers must be trained before assigning them responsible jobs. 16. Periodic medical examination of workers exposed to hazardous chemicals should be carried out. What is MSDS? What it the importance or significance? What information you get it from it OR content of MSDS? MSDS A Material Safety Data Sheet (MSDS) is a document that contains information on the potential hazards (health, fire, reactivity and environmental) and how to work safely with the chemical product. MSDSs are prepared by the supplier or manufacturer of the material. Importance /Significance 1. It is an essential starting point for the development of a complete health and safety program. 2. Provide information on the use, storage, handling and emergency procedures all related to the hazards of the material. 3. It is intended to tell what the hazards of the product are, how to use the product safely, what to do if accidents occur, how to recognize symptoms of overexposure, and what to do if such incidents occur. 4. MSDS provide the following information 
Product Information: product identifier (name),

manufacturer names,
and
suppliers
addresses,
emergency phone numbers
and
Physical Data & chemical data
Preventive measure.
Fire or Explosion Hazard Data
Preventive Measures
Reactivity Data
First Aid Measures
Health hazards data
Content of MSDS
Chemical Identity:
1. 2. 3. 1. 2. 3. 4.
Name of the Chemical Formula Synonyms Trade name Chemical Classification Regulated identification Shipping Name, Codes/Label
1. 2. 3. 4. 5. 6.
CAS No. UN No. ADR No. Hazchem (EAC) No. Hazardous Waste ID No. Hazardous Ingredients and CAS No.
2. Physical & Chemical Data:
1. Appearance, State, Odour etc. 2. Specific gravity (Water = 1) 3. Vapour density (air = 1) 4. Boiling point
5. 6. 7. 8.
Melting/Freezing point Vapour pressure Solubility in water pH
1. 2. 3. 5. 6. 7.
3. Fire & Explosion Hazard Data:
Flash point Auto ignition Temperature Flammable limits : LEL/.UEL TDG Flammability Explosion Sensitivity to Impact Explosion Sensitivity to static
electricity 8. Explosive material 9. Flammable material
10. Combustible
and
flammable
Liquid 11. Pyrophoric material 12. Hazardous Combustion products 13. Hazardous Polymerisation 14. Corrosive material 15. Organic Peroxide 16. Oxidiser 17. Others
1. 2. 4.
Reactivity Data:
3. Chemical stability 4. Incompatibility (Materials to avoid)
5. Reactivity 6. Hazardous reaction products
7. 8. 5.
Health Hazard Data:
1. TLV (ACGIH) 2. STEL/SET 3. LC50 or LD50
2. Odour threshold
3. Chromogen? Poison? Liberates poisonous fume? 4. Routes of entry 5. Body parts that may be affected 6. Effects of exposure and symptoms
7. Emergency and first aid treatment 1. Engineering controls necessary for safe handling. 2. NFPA Hazard signals 3. Special Health hazards.
1. 2. 3. 6.
Preventive Measures:
4. Ventilation required and type 2. Personal protective equipment
3. Handling and storage precautions
required and type 1. 2. 7. 3. 4. 5. 6.
Emergency and First-aid Measure:
Steps to be taken in case material is released or spilled. Waste disposal method for solid, liquid and gaseous waste. Fire, extinguishing media, special procedures and unusual hazards. Exposure - First-aid measures. Antidotes, Dosages.
1. 2. 8. 3. 9.
Additional Information / References Manufacturer / Supplier's Data:
4. Name of Firm 7. Mailing address 8. Telephone/Telex/Fax Nos. 9. Telegraphic address 10. Contact person in emergency
11. Local bodies involved 12. Standard packing 13. Tremcard Details / Ref. 14. Other
1. 2. 10.
Disclaimer:
3. 4. Q) Precaution needs to be taken in the process involving dust and gases? 5. 6. Dust Control Method: 2. Know the exposure limits of dusts. Dust below 5 microns size is invisible. Depending on toxicity, exposure limits vary from 0.1 to 10 mg/ m 3 See 2nd Schedule under the Factories Act and Employ effective measures based on this safe limit and nature of the dust. 1. 3. Elimination of dusty process e.g. Improved casting technique to eliminate dusty fettling process. 1.
4. Substitution by a less toxic or non-toxic dust, e.g. shot-blasting in place of sand blasting, metal moulds in place of sand moulds and glass fibre or slag wool in place of asbestos insulation. 5. Segregation and enclosure of the process if dust generation cannot be prevented. Dusty process should be enclosed in a room and be connected with effective exhaust and dust collector. -
Complete enclosure is the best segregation, e.g.
blasting cabinet, fuming cupboard. 1. 5. Wet methods prevent particles becoming airborne. Powdered material is suspended or dissolved in a liquid. The correct degree of wetting should be maintained and it should not be allowed to dry out. 2. 6. Local exhaust ventilation should be applied to collect the dust from the nearest possible distance. The smaller enclosure gap requires smaller exhaust rate. Suction flow should be away from the worker's breathing zone. Dust collection, filtration and disposal are the subsequent steps. Various kinds of air cleaning devices are also available. 3. 4. Flammable/ compressed Gas control method 1. Toxic gases should be kept in liquefied state if possible. 2. Cooling media and device, safety valves, pressure gauges, temperature-gauge, scrubber, level or content indicator, flare, water curtain, toxic exposure sensors and alarms, emergency bypass, safe discharge and collection, etc. should be provided as per requirement. 3. Name and quantity must be clearly mentioned to assess the hazard potential. 4. Necessary safety fittings on the gas storage tanks should be provided. 5. Gases are generally contained in cylinders, in the compressed liquefied or dissolved state. In handling and storage it must be ensured that the cylinders are protected from damage or deterioration and heat 6. Storage room for the cylinders should be dry, cool and well ventilated. 7. Highly flammable solvents, combustion waste materials, corrosives and cylinders of oxygen should not be stored near cylinders containing flammable gases. 8. fire resistant construction 9. Fire fighting equipment must be ready. 10. Warning labels are required for compressed and liquefied gas shipping containers. Similar warning signs are placed at the approaches to areas in which the gases are regularly stored and used. 11. Or unusually toxic gases, automatic devices can be purchased or built to monitor the gas concentration constantly and set off alarms if the concentration approaches a danger point. 12. Adequate personal protective equipment should be provided.
13. Training give to personnel 14. Follow MSDS 5. 6. Explain Compatibility of chemical? 7. 8. Compatibility means the ability of two or more materials to exist in close and permanent association indefinitely. Liquids and solids are compatible if the solid is soluble in the liquid. Water is compatible with alcohol (because it is miscible) but not with gasoline (e.g. petrol). 9. 10. Incompatibility means disability to co-exist permanently. Therefore incompatible materials should not be stored or kept together. For example, toluene reacts violently with some acids, plastic or rubber, therefore, these substances should be kept away. 11. 12. Incompatible materials can cause a fire, explosion, toxic release, violent reaction, and polymerisation or destroy the structure or function of a product. This information is useful for storage and handling purposes. 13. Explain the safety precaution that can b recommended for the transportation of NAPTHA by pipeline? 14. 15. Hazards: 1. Extremely flammable liquid and vapour. 2. May be fatal if swallowed and enters airways 3. Suspected of causing blood cancer if repeated over-exposure by inhalation and/or skin contact occurs. 4. Causes eye irritation. Can be absorbed through skin. 5. Repeated or prolonged skin contact can cause irritation and dermatitis. 6. May cause drowsiness or dizziness. 7. Extreme exposure such as intentional inhalation may cause unconsciousness, asphyxiation and death. 16. 17. Safety Precaution: 18. 1. 2. 3. 4. 5. 6. 7.
Keep away from heat, sparks, open flames, welding and hot surfaces. No smoking. Keep container tightly closed. Ground and/or bond container and receiving equipment. Use explosion-proof electrical equipment. Use only non-sparking tools (if tools are used in flammable atmosphere). Take precautionary measures against static discharge.
8. Wear gloves, eye protection and face protection (as needed to prevent skin and eye contact with liquid). 9. Wash hands or liquid-contacted skin thoroughly after handling. 10. Do not eat, drink or smoke when using this product. 11. Use only outdoors or in a well-ventilated area. 12. In case of fire: Use dry chemical, CO2, water spray or fire fighting foam to extinguish. 13. If on skin (or hair): Take off immediately all contaminated clothing. Rinse skin with water/shower. 14. If in eye: Rinse cautiously with water for several minutes. 15. Post hazards warning information in the work area. In addition as part of an ongoing education and training effort, communicate all information on the health and safety hazards of NAPHTHA to potentially exposed worker 16. Workers whose clothing has been contaminated by Naphtha should change into clean clothing promptly. 19. 20. Q) Importance of storage, handling and labelling of chemical? 21. 22. Importance of labelling of chemical: 1. Chemical containers must be labelled to identify their contents, and sometimes their associated hazards. 2. Labelling is important to prevent accidental misuse and inadvertent mixing of incompatible chemicals. 3. Proper labelling also facilitates quick decision-making and action in the event of an emergency (i.e., spillage, exposure, etc.), and avoids the expense associated with handling, management, and disposal of unknown chemicals. 4. Provide the Instructions and information on the safe storage, handling, use and disposal of the chemical. 5. May be used to inform hazard and risk assessments in the workplace, and establish appropriate work practices and processes to control the risks during use. 6. Distinguish between hazardous and non-hazardous chemicals. 7. Use the physical state of the hazardous chemical (dry, liquid or gas) to determine general storage location guidelines: 8. Distinguish between hazardous and non hazardous area. 9. To identify nature of chemical ( Flammable, explosive, non flammable) 10. Correct labelling determine the action to be taken in emergency 23. 24. How you handle the leakage of the chlorine being as the safety officer? 25. 1. Chlorine leaks should be investigated by authorized, trained personnel 2. Evacuate immediate area. 3. Uncontrolled releases should be responded to by trained personnel using preplanned procedures.
4. Proper protective equipment, should be used in the event of a significant release from a single cylinder. 5. Use only non-sparking tools. 6. Attempt to close the main source valve prior to entering the area. 7. If this does not stop the release (or if it is not possible to reach the valve), allow the gas to release in-place or remove it to a safe area and allow the gas to be released there. 8. Protect personnel attempting to shut-off with water spray. 9. Monitor the surrounding area for the level of Chlorine and Oxygen. 10. The atmosphere must have at least 19.5 percent Oxygen before non-emergency personnel can be allowed in the area without Self-Contained Breathing Apparatus. 11. Use with adequate, ventilation 12. Follow MSDS provided by manufacture 13. Check designing of layout of area with due consideration for adequate natural or mechanical ventilation, 14. Check availability and use of adequate and suitable personal protective equipment 15. Water shall never be used on a chlorine leak as it always makes the leak worse due to the corrosive effect. 16. Chlorine is heavier than air; therefore persons should be instructed to keep above and upwind of the leak. 17. If a leak occurs in equipment in which chlorine is being used, the supply of chlorine shall be shut off and chlorine which is under pressure at the leak shall be disposed off safely. 18. It is important to keep above and to the windward side of escaping chlorine gas. 19. Leaks around valve stems usually may be stopped by tightening the packing nut or gland. If this does not stop the leak, the container valve shall be closed and the chlorine, which is under pressure in the outlet piping, shall, be disposed off. If a container valve does not shut off tight, the outlet13. 20. Cap or plug should be applied. In case of a valve leak on a ton-container, the container shall be rolled so that the valves are in a vertical plane with the leaking valve on top; this is important. 26. 27. Chapter 6-9-14 28. Q) What is corrosion and Erosion? (4M) 29. Q) What is corrosion and the factor responsible for it? Mention different corrosion and mention any one corrosion in detail? (8M) 30. Q) What is corrosion and erosion? What are the causes and preventive measure? (8M) 31.
32. Corrosion- Corrosion is an electrochemical reaction between a metal and its environment. It results in a loss of metal or weakening of it Corrosion reaches deeply, creates maintenance problems and incurs cost of loss in lacs of rupees over the years. 33. Erosion- Erosion is type of corrosion is a degradation of material surface due to mechanical action, often by impinging liquid, abrasion by slurry, particles suspended in fast flowing liquid or gas, bubbles or droplets, cavitations, etc. 34. Types of Corrosion 1. General and local corrosion- General corrosion takes place due to a corrosive chemical or impurity over the exposed surface. 2. External corrosion- External corrosion occurs by material of insulation. 3. Galvanic- corrosion happens due to current flowing between tow dissimilar metals which form a galvanic cell. 4. Crevice- Crevice or contact corrosion occurs at the point of contact of a metal and non-metallic material, e.g. threaded joints. 5. Knife-line- Knife-line corrosion takes place between parent and weld metals, e.g. austenitic stainless steels. 6. Intergranular - corrosion occurs in stainless steels heated upto 500-800 °C and then exposed to corrosive conditions. 7. Scaling- Corrosion due to oxidation at high temperature is called scaling, e.g. steam boilers. 8. Exfoliation- is a type of scaling caused by oxidation in steam atmosphere e.g. feed water heaters. 9. Corrosion pitting- Corrosion pitting results from electrochemical potential set up by differences of oxygen concentration inside and outside the pit. 10. erosion - Erosion is a type of corrosion and is caused by flow restriction or change of direction 35. Galvanic Corrosion 1. Galvanic corrosion is an electrochemical process in which one metal corrodes to another when both metals are in electrical contact, in the presence of an electrolyte. 2. Dissimilar metals and alloys have different electrode potentials, and when two or more come into contact in an electrolyte, one metal acts as anode and the other as cathode. 3. The electro potential difference between the dissimilar metals is the driving force for an accelerated attack on the anode member of the galvanic couple. The anode metal dissolves into the electrolyte, and deposit collects on the cathodic metal. 4. The presence of an electrolyte and an electrical conducting path between the metals is essential for galvanic corrosion to occur.
5. A common example of galvanic corrosion is the rusting of corrugated iron sheet, which becomes widespread when the protective zinc coating is broken and the underlying steel is attacked. 36. 37. Preventive measure Electrically insulate the two metals from each other. Ensure there is no contact with an electrolyte. Using antioxidant paste is beneficial for preventing corrosion between copper 38.
and aluminium electrical connections. Choose metals that have similar electro potentials. Cathodic Protection
The main factors which affect corrosion are /Causes of corrosion
39. 1. More the reactivity of metal, the more will be the possibility of the metal getting corroded. 2. The impurities help in setting up voltaic cells, which increase the speed of corrosion 3. Presence of electrolytes in water also increases the rate of corrosion 4. Presence of CO2 in natural water increase rusting of iron. 5. A rise in temperature (within a reasonable limit) increases the rate of corrosion. 6. Spillage of corrosive chemical, Scale formation on plates and tubes and poor housekeeping 7. Rain water and plant water 8. Two incompatible material increase the rate of corrosion. 9. The rate of the corrosion is greatly influenced by the relative sizes of cathodic and anodic areas. If the metal has smaller the anodic area and larger the cathodic area exposed to corrosive atmosphere, more intense and faster is the corrosion occurring at anodic area 10. A metal with low hydrogen over voltage on its surface is more susceptible for corrosion. 40. 41.
Corrosion Prevention:
42. 1. Substitution of non-corrosive or less corrosive material (e.g. SS instead of MS) 2. Selection of such material from the design and erection stage avoids most of the corrosion problems. 3. Then selection of powder coated metal parts (sheets, structural members, machine parts, guards, covers etc.) instead of painted, give long life.
4. Mild steel parts of tanks structures piping, machines and vessels must be regularly painted by anti-corrosive paints. 5. Protection from rain and plant water, dripping and leaking of corrosive chemicals, oxidation and contact of zinc and copper is necessary. 6. Rapid cleaning of spillage, good housekeeping, 7. control of flow, fluctuations and vibrations, 8. water softening and removal of salts, checking of scale formation on plates and tubes, thickness measurement and defect monitoring by NDT methods 9. Two compatible metals prevent or slow down the rate of corrosion. 10. A strategically placed gasket i.e. to provide insulating material between the two metals. 11. Cathodic protection and conversion coating. 12. Crevice corrosion can be avoided by choosing materials having corrosion resistance. Stainless steels are prone to crevice corrosion and not recommended for such use. 13. Use of non-metallic material like plastic. 14. Applying monomolecular film (inhibitor) of grease, paint, synthetic organic coating or a plastic sheet (liner) over the surface. 15. Inhibitors like phosphonates are used in cooling water for corrosion control. 16. Use of acid pickling as corrosion inhibitors. 43. Explain the work permit system? Gives the different work permit in the chemical plant? Explain the Hot work permit system? 44. 45. Work permit system- This is a formal written system document used to closely control certain types of activities, tasks, processes or work that have specific hazards or are potentially hazardous. 46. 47. Types of work permit system in chemical plant: 48. 1. 2. 3. 4.
General and cold work permit Hot work permit Confined (Vessel) work permit Excavation permit
5. Electrical work permit 6. Working at height permit 7. Chemical area work permit
8. 9. Objective of work permit system: 10. 1. 2. 3. 4. 5. 6. 7.
To provide the information about hazards involved in operation To provide safety precautions need to be taken to mitigate them For safe working operation To reduce accident Suggest to do not violate the standard operating procedure. To improve the efficiency of the worker and productivity To increase the worker interest towards work
11. 12. Hot Work Permit: 1. PURPOSE- The main purpose of hot work permit is to identify the hazards in welding, cutting etc. And what is the control measure need to adopt to mitigate them. 2. For welding and cutting, working with open flames or sparks due to grinding, chiselling etc. or where hot work is dangerous or may cause fire. 3. Hot work or Fire Permit is necessary for the safe work operation. 4. The area must, first, be made free from hazards of fire and explosion. 5. Tests for explosive air mixture or possibility should be carried out. 6. All lines to the vessel shall be blinded or' disconnected. 7. Sufficient vents and flameproof light shall be provided. 8. Fire protection and alarm shall be kept ready. 9. Dangerous work shall not be allowed in the vicinity. 10. Water facility shall be used to extinguish sparks, hot slugs etc. 13. 14. Q) What is safe work permit system prepare safe work permit system for working in confined space? 15. Vessel (Confined) Entry Permit: 1. Under section 36 (2) of the Factories Act 1948, no person in any factory shall be required or allowed to enter any confined space (chamber, tank, vat, pit, pipe, flue etc. having dangerous fumes likely to involve risk) until all practicable measures have been taken to remove any fumes which may be present and to prevent any ingress of fumes and unless a certificate in writing has been given by a competent person based on a test carried out by himself that the space is free from dangerous fumes and fit for persons to enter. 2. Such person is wearing suitable breathing apparatus and a safety belt securely attached to a rope (life line) die free end of which is held by a person outside the confined space. 3. Isolation of the vessel from sources of energy or harmful substance by way of cooling, 4. Disconnection, blinding, blanking etc., draining, cleaning, washing and purging to make free from toxic gases. 5. Testing the air for oxygen or toxicity content, opening top and bottom connections for good ventilation, lighting. 6. Exit, wearing safety belts, helmet and suitable breathing equipment, allowing low voltage (24 volts) light, standby arrangement etc. are essential requirements. 16. Format
***See page no 16-18***
17. Chapter 12 -13
18. What are the statutory requirements for fired and unfired pressure vessel under the Maharashtra factory rules 1963? 19. 65. Safety measures for pressure plant and vessels operated under pressure over atmospheric pressure – 20. 21. (1) In this rule,22. 23.
(a) 'competent person' means person who has experience of conducting a
thorough examination and pressure tests, of a pressure vessel or plant and of making a full report on its condition; 24.
(c) 'Pressure plants' means the pressure vessel along with its pipings and
other fittings operated at a pressure greater than the atmospheric pressure 25.
(d) 'Pressure vessel' means any vessel subjected to or operated at a
pressure greater than the atmospheric pressure. 26. 27. (2) Every pressure plant or pressure vessel used in any factory shall beA. Designed on sound engineering practice; B. sound construction and material and of adequate strength and shall be free from any defect; and C. properly maintained in a safe working condition: 28. (3) 29. (i) Every pressure plant or pressure vessel shall be fitted with30. (a) a suitable safety valve or other effective device, to ensure not exceeding maximum safe working pressure (b) a suitable pressure gauge , to ensure not exceeding twice the maximum safe working pressure (c) a suitable stop valve or valves , pressure vessel isolated from other vessels (d) a suitable nipple and globe valve, for checking the accuracy of pressure gauge (e) A suitable drain cock or valve or a plug to ensure effective draining of liquid that may be collected in the pressure vessel. 31. 32. (ii) Every pressure gauge, stop valve, nipple and globe valve, shall be mounted at a height not more than 1.5 metres from the working level. 33. (iii) Every pressure plant or pressure vessel not constructed to withstand the maximum possible working pressure
34. (iv) In case of a jacketted vessel in which heat is transmitted by means of steam or other media in the jacket causing pressure rise controlled by a suitable device as not to allow the safe working pressure of the vessel being exceeded. 35. 36. (4) Ever pressure plant in service shall be thoroughly examined by a competent person,(a) Externally once in every period of six months; (b) Internally, once in every period of twelve months, and (c) Hydraulic test once in a period of four years. 37. 38. (6) 39. (i) The maximum safe working pressure and the date of the last examination shall be plainly marked on every pressure vessel 40. (ii) No pressure plant or pressure vessel has remained isolated or idle for a period exceeding 6 months 41. (iii) No pressure vessel or pressure plant shall be taken into use for the first time in any factory unless42.
(a) A certificate specifying the maximum safe working pressure and the tests
43.
(b) It is thoroughly examined by a competent person
44. 45. Q) Define terms of pressure vessels and its safe operation? 46. 47. 'Pressure vessel' means any vessel subjected to or operated at a pressure greater than the atmospheric pressure. 48. Safe operation of pressure vessel 1. Designed on sound engineering practice; 2. sound construction and material and of adequate strength and shall be free from any defect; and 3. properly maintained in a safe working condition 4. Suitable safety valve or other effective device, to ensure not exceeding maximum safe working pressure 5. Suitable pressure gauge , to ensure not exceeding twice the maximum safe working 6. 7. 8. 9.
pressure Suitable stop valve or valves to ensure pressure vessel isolated from other vessels Suitable nipple and globe valve for checking the accuracy of pressure gauge Spring loaded safety valves with oil seals are desirable. For high pressures, rupture or bursting disc or rupture diaphragm should also be
provided. 10. Pressure reducing or pressure control valves are necessary.
11. Safety valve should be connected nearest (close) to the vessel. It should not be connected where pulsating pressure fluctuates. 12. Suitable drain cock or valve or a plug to ensure effective draining of liquid that may be collected in the pressure vessel. 13. Every pressure plant or pressure vessel not constructed to withstand the maximum possible working pressure 14. In case of a jacketted vessel in which heat is transmitted by means of steam or other media in the jacket causing pressure rise controlled by a suitable device as not to allow the safe working pressure of the vessel being exceeded. 15. Ever pressure plant in service shall be thoroughly examined by a competent person,a. Externally once in every period of six months; b. Internally, once in every period of twelve months, and c. Hydraulic test once in a period of four years. 16. The maximum safe working pressure and the date of the last examination shall be plainly marked on every pressure vessel 17. No pressure plant or pressure vessel has remained isolated or idle for a period exceeding 6 months 18. No pressure vessel or pressure plant shall be taken into use for the first time in any factory unless(a) certificate specifying the maximum safe working pressure and the tests (b) it is thoroughly examined by a competent person 49. 50. Q) Describing brief about reliability of pressure vessel and precaution against over pressure vessels? 51. 52. Reliability of pressure vessel- It is defined as the probability that a pressure vessels will perform a required function under below stated condition. 1. Every pressure plant or pressure vessel not constructed to withstand the maximum possible working pressure 2. Pressure of the pressure vessel should not exceed beyond maximum permissible limit. 3. Material and of adequate strength and shall be free from any defect; and 4. properly maintained in a safe working condition 5. Pressure relief devices such as, safety valve, relief valve, fusible plug, stop valve, 6. 7. 8. 9.
nipple and globe valve etc should be provided and regularly checked Drainage valve provided to drain the vessel. Suitable pressure gauge with dial range 1.5 times MPWP. Pressure vessel should not be idle more than 6 months The maximum safe working pressure and the date of the last examination shall be
plainly marked on every pressure vessel 10. Periodically maintenance has been carried out to check for any abnormalities. 11. Pressure vessel are to be tested for there assessment of reliability. Two types of test 1) pressure test and 2) NDT test 53.
54. If pressure inside a tank rises due to any reason, it may burst the tank from its weakest part or cause leakage from where it is possible. it may create fire, explosion or toxic hazard. Therefore to avoid such situation a following pressure relief device is necessary. 1. A safety valve is a common pressure relief device. It can be set to a predetermined (desired) pressure and when pressure exerted on it exceeds that pre-set value, it automatically opens and allows the pressure to release in the atmosphere 2. Relief valves do not full open at set pressure like safety valve, but open slightly and then open further as the pressure increases. 3. It is better and safer to keep the pressure under control by controlling heat source, temperature or the rate of reaction. 4. Bursting (Rupture) Discs are preferred where pressure rise is fast like explosion. 5. Stop or isolation valve to shutoff the pressure source. 6. Suitable pressure reducing valve (PRV) or automatic pressure regulator to disallow the pressure greater than the MPWP 7. Vacuum breaker is also a type of pressure relief device and works like a spring loaded safety or relief valve but in the reversed direction. 8. Double Safety Valves are required for bulk storage tanks of chlorine, ammonia, LPG, ethylene oxide etc. 9. If addition is controlled, pressure can also be controlled. In nitration process addition of nitric acid should be at a slow or controlled rate, otherwise rapid pressure rise can burst the vessel. 55. Q) Describe the importance of assessment of reliability of vessel and their text check? 56. Importance of assessment of reliability of vessel 1. To find out or to identify the
pressure vessel not constructed to withstand the
maximum possible working pressure 2. To instruct that the Pressure of the pressure vessel should not exceed beyond maximum permissible limit. 3. Provide the information about Material and of adequate strength and shall be free from any defect; and 4. To ensure the pressure vessel properly maintained in a safe working condition 5. To ensure Pressure relief devices such as, safety valve, relief valve, fusible plug, stop 6. 7. 8. 9.
valve, nipple and globe valve etc should be provided and working properly To ensure the Drainage valve provided to drain the vessel. To check Suitable pressure gauge with dial range 1.5 times MPWP. To provide information that the Pressure vessel not be idle more than 6 months To provide the information of the maximum safe working pressure and the date of the last examination shall be plainly marked on every pressure vessel
10. To instruct periodically maintenance has been carried out to check for any abnormalities. 11. Pressure vessel are to be tested for their assessment of reliability. Two types of test 1) pressure test and 2) NDT test 57. 58. Q) Pressure relief valve and rupture Disc? (4M) 59. Pressure Relief Valve 1. A pressure relief valve is a common pressure relief device. 2. It can be set to a predetermined (desired) pressure and when pressure exerted on it exceeds that pre-set value, it automatically opens and allows the pressure to release in the atmosphere 3. It automatically closes down also, after release of the excess pressure. 4. Safety valves are of four types - spring loaded, weight lever, solenoid and pilot. 5. Safety valves are used to release gas or vapour but not the liquid. 60. Rupture Disc: 1. A Rupture Disc is required for the fast release or more flow from a bigger size hole or if internal pressure is too high and chokes the safety valve. 2. This disc is selected based on many parameters (e.g. type of chemical, working pressure, temperature, reaction, material of the tank, viscosity, corrosivity, toxicity and flammability of the content etc.) 3. One disc can be used for one pressure i.e. its set-pressure cannot be changed like safety valve, and after rupture the same disc cannot be reused. 4. Once opened, it cannot reset at the lowered pressure like safety valve, and will allow the whole mass to come out till the hole is closed or the disc is replaced. This is its disadvantage. 5. Therefore, it is inadvisable on tanks containing flammable gases or liquids. 61. Q) What are the different inspections technique used in chemical plant? Elaborate any one technique in detain? 62. There are three different inspection technique used in chemical plant 1. Planned inspection. 2. Continuous inspection. 3. Statutory inspection. 63. 64. Planned Inspection- Further classified in four steps65. 1. Periodic Inspection : 66.
Plant, machinery, equipment, lifting machines, pressure vessels, apparatus, procedures, methods and health of the workers should be examined at regular
pre-planned period. Statutory forms, checklists, tables and period of inspections, if any, must be
strictly followed. It should be deliberate, thorough, detailed and systematic. Safety committee, safety officer, competent person, safety consultant, industrial hygienist, doctors and other safety and health personnel should carry out such
inspections. Storage and pressure vessels are to be tested and checked for the assessment of their reliability. Testing of pressure vessels and their parts is most essential. Mainly two types of tests are in practice, pressure test and non-destructive tests (NDT). Pressure tests include hydraulic, pneumatic and combined. NDT includes radiography, dye penetrant, magnetic particle and ultrasonic. NDT methods can be used before or after pressure test methods. Mechanical tests are also
employed for fusion welded seams and test plates. Following inspection also been the part of periodic inspection carried by competent personI.
Ultrasonic test for creep damage detection and evaluation.
II.
Eddy current test for detection and evaluation of Cracking
III.
Ultrasonic test for the detection of fatigue and stress corrosion cracks
IV.
Electromagnetic testing (RFT) of ferromagnetic heat exchanger tube bundles for detection and evaluation of corrosion damage
V. VI.
Residual stresses measurement for heat treatment reliability Suitable compatibility test of material of construction with chemical
67. 2. Intermittent Inspection:
It is carried out at irregular intervals to check new
equipment installations, procedures and workers; modifications, accident analysis etc. Some partial inspections are also carried out at uncertain intervals. 68. 3. General Inspection: It is general or routine' inspection to check places which are not covered by .other inspections. Isolated areas, parking places, side - walks, fencing, and light - illumination, reporting after long shutdown etc. are checked by such general or overhead inspections. 69. 4. Special Inspection : Safety or hazard analysis, accident investigation, checking of dangerous operation or vessel, building safety, subjects of complaint only, inspection during special campaigns and new installations, and only for storages, processes,
methods, hand-tools, scaffolds, guards, facilities, protective equipment etc., fall within this category. 70. 71. Continuous
(ongoing)
Inspection:
Some personnel like safety officer,
maintenance men, electricians etc. spend their all time in observing certain equipment, vessels, processes, operations, safety devices, personal protective equipment etc., to maintain them in safe and efficient working condition. 72. 73. Statutory Inspection: This is carried out by Factory Inspectors and other authorities under various safety statutes (See Chapters 27 & 28) to check the implementation of statutory provisions. Strict and timely compliance is necessary. Breach of law may attract prosecutions. For most of the factories where there is no system of internal inspection, statutory (government) inspection is the only effective inspection and therefore it should be carried out in detail and the governments must employ sufficient staff to achieve better safety inspections. 74. 75. Q) Explain the importance of safety checklist? Design safety checklist for preventive maintenance of chemical plant? 76. 77. Importance of Safety checklist 1. Process or system checklists are used to identify common hazards and ensure compliance with standard procedures. 2. Checklist is a convenient means of communicating minimum acceptable levels and hazard evaluation. It can be as detailed as necessary to satisfy the specific situation. 3. Checklists should be regularly audited and updated. They provide results quickly. 4. Checklists are complementary to the inspection technique and makes the 5. 6. 7. 8. 9.
inspection more perfect, speedy and systematic To reduce the no of accident To develop safe working environment. To improve the worker efficiency and productivity. To reduce accidental cost. To reduce the loss of time.
78. 79. Safety checklist for chemical plant 80. 81. Checklist82. Name
&
Address
of
_______________________________________________
the
Factory:
83. Inspected on
Date:
Time:
__________ 84. Inspected by _________________________________
1. Chemicals Safety
Are appropriate labels and hazard warnings applied on all chemicals containers?
Are Material Safety Data Sheet (MSDS) available for all chemicals used in the plant site?
Are these MSDS up-to-date?
Are these chemicals placed separately in the warehouse?
Is emergency procedure (spillage, splash, poisoning) available and easy to read?
Is chemical handling training provided for the workers?
2. House Keeping
Where cleanliness required?
Lifting machinery safe moving?
Tools etc. in safe position?
Safety posters, precautionary notices in all rooms, floor displayed? Where more necessary?
Motors, gears, pulleys, belts, chains, coupling etc. guarded? What not guarded?
3. Gas Cylinders Safety
Are gas cylinders placed in a special room, fenced and locked?
Are gas cylinders properly labelled?
Are empty gas cylinders separated from new ones?
Are gas cylinders protected from falling and mechanical damage?
Earthing, FFE, & PPE, Cautionary notice provided?
Inorganic & organic liquid separated?
4. Electrical Safety
Are electrical equipments, fittings and tools in the plant site regularly checked and maintained?
Is access to the high voltage electrical equipments restricted to authorize persons only?
Are electrical safety signs and warnings available and easy to read?
Are power panels, controls, receptacles and wiring covered?
Is power cable rack condition good?
Are power tools properly grounded?
Is temporary lighting installed securely?
5. Lighting
Are lighting for every workplace and workstation enough according to the regulation and working requirements?
Is lighting regularly checked and monitored and the record kept?
Is emergency lighting available and reliable?
6. Machinery
Is preventive maintenance of machinery regularly carried out?
Are machine guards properly installed and maintained?
Have the workers been trained about machinery operation and maintenance?
Are there enough safety signs around these machines?
Are safety equipments installed on the machinery and function properly?
7. Pressure vessels
Is all the pressure vessels periodically checked and monitored?
Are appropriate pressure and temperature gauges installed on it?
Are normal operating pressure and temperature ranges indicated on the gauges?
Is safety relief valve installed on the pressure vessel?
Is the pressure gauge periodically calibrated?
Is calibration record kept?
Are records of hydrostatic pressure test kept?
8. Personal Protective Equipments
Is personal protective equipment (PPE) provided and free of charge?
Is provided PPE effective, comfortable and well fitting?
Is PPE condition regularly checked and monitored?
Is area that requires PPE wearing clearly described?
Is PPE implemented based on hazards assessment results?
Is PPE selection, implementation and maintenance procedure established?
9. First Aid
Is a first aid box provided at every workplace and easily accessible?
Is the first aid box content complete and regularly checked?
Is the usage of its content recorded?
Is there a clear sign for the first aid box?
10. Fire Precautions
Are there enough fire precaution signs throughout the plant site?
Are fire alarms and smoke detectors function well and regularly checked and maintained?
Is fire pump regularly tested run and maintained?
Are fire hydrants availability and coverage area adequate for the plant site?
Are fire hydrants accessories regularly checked and maintained?
Are fire extinguishers properly placed and protected?
11. Emergency Response
Does the plant site have an Emergency Response Procedure (ERP)?
Has everyone in the plant site been trained about ERP?
Is ERP training carried out periodically?
Are emergency response teams determined?
Can exit and evacuation routes signs be easily readable?
85. Q) Explain the importance of preventive maintenance in petrochemical industries? Design safety checklist for preventive maintenance of chemical plant? 86. Importance of Preventive maintenance 87. 1. Equipment downtime is decreased and the number of major repairs are reduced 2. Better conservation of assets and increased life expectancy of assets, thereby eliminating premature replacement of machinery and equipment 3. Reduced overtime costs and more economical use of maintenance workers due to working on a scheduled basis instead of a crash basis to repair breakdowns
4. Timely, routine repairs circumvent fewer large-scale repairs 5. Improved safety and quality conditions for everyone. 6. To improve the performance and safety of the equipment at your property. 7. Preventative maintenance assures the efficiency and speed of your equipment. 8. Regularly scheduled preventative maintenance can confirm that the machine is working properly and avoid emergency situations and outages. 9. Saves Money 10. Saves Time 11. Helps Safeguard Your Data 12. Maintenance Improves Performance 13. Provides increased component operational life and availability 14. Allows for pre-emptive corrective actions 15. Results in decrease in equipment and/or process downtime 16. Lowers costs for parts and labour 17. Provides better product quality 18. Improves worker and environmental safety 19. Raises worker morale 20. Increases energy savings 88. Q) Importance of emergency maintenance? 89. Others 90. 91. Q) Draw the sketch of emergency control panel and explain th meaning of HAZCHEM code? 92. 93. Emergency control panel- It contain the following information 1. 2. 3. 4. 5. 6.
Correct technical name of dangerous good United Nation Class no. Class Label HAZCHM Code Name and telephone no of emergency service Specialist advice
94.
95. 96. 97. HAZCHEM CODE- "Hazchem Code" is a very simple and effective communication device to enable personnel to know at once what precautions or actions are required to deal with emergencies like spills, leaks or fire 98. 99. It Contain: 1. 2. 3. 4. 5.
Firefighting Number PPE Risk of violent reaction Spillage Evacuation 100. 101.
For fire-fighting response:
102.
1. Jets / Coarse Spray
103.
2. Fog / Fine.
104.
3. Foam
105.
4. Dry Agent for personal
106. 107.
Protection against a fire or spill response, the following codes apply
108.
C
ategory
109.
Re
activity
110. n
Protectio
111.
Spill
Response
112.
P
113.
116.
R
117.
120.
S
124.
S
128.
T
132.
T
136.
W
137.
140.
X
141.
144.
Y
148.
Y
152.
Z
156.
Z
160. 162.
E
163.
121.
V
V
114.
Full
122.
BA
126.
BA for fire
only 129.
130.
BA
134.
BA for fire
115.
Dilute
139.
Contain
only
145.
V
V
138.
Full
146.
BA
150.
BA for fire
only 153.
154.
BA
158.
BA for fire
only 161.
Consider evacuation
For Example
164. 165.
Class
substance
UN No.
HAZCHM
166.
2
Ammonia
1005
2PE
167.
2
Chlorine
1017
2XE
168.
2
Hydrogen
1049
2SE
169. 170. 171.
Q) Detail about the TREM Card?
172. 1. As per the Central Motor Vehicle act 1988 and rule 1989, The driver of the dangerous 2. 3. 4. 5. 6. 7. 8.
and hazardous goods carrying vehicle is supposed to carry TREM Card with him It provides very useful information about the properties of chemical This card provide the various information in the case of spillage of material take place It should be in three different languages. Hindi, English and Local language. Rule 181- its responsibility of consigner to prepare TREM card of a particular chemical Rule 133- Its responsibility of driver to carry TREM Card According to CMV rule, Driver undergo training of three day from recognised institute TREM Card Contain Nature of the chemical Nature of the hazards Fire and explosion data
Physical and chemical properties PPEs First Aid Emergency Action Address of the owner Emergency contact no
173. 174.
Q) Earthing & Bonding?
1. Bonding - A way of reducing the risk of getting an electric shock. 2. Earthing - A way of preventing electric shocks. 3. Tanks and piping containing flammable substance should have double earthings of appropriate type. 4. Earthing pit should be recharged periodically for easy flow of the current. 5. Resistance should be measured (below 10 K-ohm) and recorded. 6. IS: 3043 is useful for earthing code. 7. Filling (inlet) pipe should be extended up to bottom or an inner limpet coil should be provided to avoid free fall and static charge due to material flow. 8. Pipe joints/flanges should have copper bonding to maintain electric continuity. 9. Flange-guard is useful to divert the leakage downwards. 10. While loading or unloading flammable liquids or gases, the vehicle (road or rail tanker) should also be earthed during such operation. 175.
Q) Spark Arrestors?
176. 1. A spark arrestor is any device which prevents the emission of flammable debris from combustion sources, such as internal combustion engines, fireplaces, and wood burning stoves. 2. Spark arrestors play a critical role in the prevention of wildland fire and ignition of explosive atmospheres. 3. According to central motor vehicle act 1989, rule 129-A, all the good carriage carrying dangerous or hazardous good to human life shall be fitted with the spark arrestor.
4. Types 1. Centrifugal
1. Centrifugal type spark arrestors employ stationary vanes, baffles, or other devices to trap large particles by centrifugal force.
2. These spark arrestors are typically found on heavy agricultural and construction equipment (tractors, combines, bulldozers, etc.) 2. Screen
1. Screen type spark arrestors use a physical mesh to prevent large particles from leaving the exhaust system. 2. This is the simplest and most common type of spark arrestor. Screen type devices are used on most motorcycles, ATVs, and small engines. 177.
Q) Explain the onsite emergency plan in chemical industry?
178.
The purposes of this plan are:
1. To protect persons and properly of your factory in case of all kinds of accidents, dangerous occurrences at any time. 2. To inform people and surroundings about above happening if it is likely to adversely affect them. 3. To inform authorities including helping agencies (doctors, hospitals, fire, police, transport etc.) 4. To identify, various kinds of possible hazards, their places, potential and damaging capacity 5. Review, revise, redesign, replace or reconstruct the process, plant, vessels and control measures if so assessed. 179.
Some model guidelines are given below.
180.
Site Plan of the Factory and Surrounding:

Prepare a plan of the factory premises and surroundings showing therein the areas of various hazards such as fire, explosion, toxic release etc., and also location of assembly points, fire station of equipment room, personal protective equipment room, telephone room, first aid or ambulance room, emergency control room, main gate, emergency gates, normal wind direction, north direction, outside fire station, police station, hospital and other services.
181.
Types of Overall Emergencies:
3. Describe types of emergency and how it can arise in or near your plant. Fire (small and big), explosion, toxic exposure, strike, storm, flood and other hazardous possible situations shall be described with reasons. 182.
Assessment of In-plant Hazards:
4. Give details of assessment of in-plant hazards and control measures 183.
Emergency Organisations and Functions:
5. Prepare the organisation and mention their responsibilities and duties in case of emergency or dangerous occurrence. 184.
Telephone Operators' Guide:
6. Telephone is the essential communication system. Tabulate all your internal telephone numbers and outside emergency numbers for information and help 185.
Emergency Shutdown Procedure:
7. Looking to the gravity of emergency, if it seems necessary to shut down the process or plant, detailed instructions shall be laid down for plant/area. 186.
Link with Off-site Emergency Plan:
8. To deal with the emergencies extending outside the factory premises and affecting neighbouring area, off-site emergency control procedure and public warning procedure shall be laid down and followed. 187.
Pre-information to Doctors and Hospitals:
9. Antidotes, medicines and remedial measures shall be conveyed to surrounding doctors and hospitals who will verify them before their use. 188. 189.
Q) Transportation of Chemical and importance of Tremcard?
190. 191.
Transportation of chemical
1. Transportation is by road, rail, water or air. 2. Containers are mostly standardised to ensure safety during transit. 3. When a truck or tanker meets with accidents or leaks on the way, it creates problem. 4. Fire or explosion can cause harm to public or property.
5. Corrosive or toxic chemical can cause harm to public, animals, birds and environment. 192.
Below are the safety precautions need to be taken to overcome the
above problem 1. Goods carriage carrying dangerous or hazardous goods to human life, shall be fitted with a spark arrester. 2. Every consignor shall supply to the owner of the goods carriage accurate and sufficient information about the hazardous goods so as to enable such owner and his driver to comply with and be aware of the risk to the health or safety of any person. 3. Valid registration to carry hazardous goods listed first aid, safety equipment, antidote; training to driver to control transport emergency are also necessary. 4. Driver 'shall observe at all times all the precautions to prevent fire, explosion or escape o hazardous goods, shall ensure parking in a safe place and under control and supervision of himself or some other competent person 5. Tremcard should be given to workers. The content of a 'Tremcard' should include name of cargo (material), nature of its hazard, protective devices including PPE and emergency action to (1) inform Police and Fire Brigade (2) Spill or gas control (3) Fire control and (4) First aid. 6. The transporter should carry 'Emergency kit' containing tool kit, emergency lighting, fire extinguisher, protective clothing, breathing equipment and first-aid kit 7. Proper training to drivers of hazardous chemicals is legally required. Safety checklist or transport vehicles shall be prepared and used. 8. The driver transporting any hazardous goods shall forthwith report any accident involving such goods to the nearest police station and also the owner of the goods carriage or the transporter. 193. 194.
***** For importance of Tremcard See above**** Q) Important provision of factories act 1948 related to chemical
industry? 195.
The Factories Act contains specific provisions on chemical safety.
1. Section 2 (cb) defines 'hazardous process'. 2. Section 7A and 7B specify general duties of occupiers and manufacturers for health and safety. 3. Sections 11 to 20 regarding cleanliness, disposal of wastes and effluents, ventilation and temperature/dust and fume, overcrowding, lighting, drinking water, latrines, urinals and spittoons are all useful for chemical factories also. 4. The whole chapter-IV (Sections 21 to 41) on safety is also relevant. Provisions of hoists and lifts, lifting machines, revolving machinery, pressure plant, floors, stairs and means of access, pits, sumps, openings in floors, excessive weights, and
protection of eyes, precautions against dangerous fumes, use of portable electric light, explosive or inflammable dust, gas etc., fire and building safety are also useful in chemical factories 5. Chapter IV A (Sections 41 A to 41 H) regarding hazardous processes provides for site appraisal committees, disclosure of information, health and safety policy, medical examination (pre and post employment) of workers, health records, supervision, emergency standards, permissible limits of toxic exposure (Second Schedule), safety committee, duty to warn about and remove imminent danger. 6. Chapter V (Sections 42 to 50) on welfare provides for washing facilities, cloak room, first-aid, ambulance room, canteen, rest and lunch room, and welfare officer. 7. Sections 87 to 91 A regarding dangerous operations, notice of accidents and diseases, inquiry, samples and health surveys are also useful. 8. Section 87A prohibits employment on account of serious hazard. 9. Section 96A for penalty for breach of section 41B, 41C or 41H is very severe. 10. By section 104A burden of proof is shifted on a person who fails to fulfil the duty under this Act. 11. Section 111A creates worker's right to get information relating to their health and safety and to get trained for that. 12. The Third Schedule lists 29 occupational diseases most of which are due to chemicals. 196.
Q) Write down the onsite emergency plan in chemical industry? Its
importance roles and responsibility of people involved? Mention under which legal requirement it is required? 197.
Statutory Provision
1. Section 41B(4) of the Factories Act, 1948 requires an onsite emergency plan and detailed disaster control measures for the safety of the factory workers and the general public living in the vicinity of the factory. 2. The occupier is required to inform the workers and the public about the safety measures to be taken in the event of an accident. 3. Rule 13, 14 and Schedule 11 & 12 of the Manufacture; Storage and Import of Hazardous Chemicals Rules, 1989 and Rule 5,7,9 and 10 of the Chemical ' Accidents (Emergency Planning, Preparedness and Response) Rules, 1996 also provide for on-site and off-site emergency plans. 198.
Importance of on-site planning
1. Helps To protect persons and properly of your factory in case of all kinds of accidents, dangerous occurrences at any time. 2. Helps To inform people and surroundings about above happening if it is likely to adversely affect them.
3. Helps To inform authorities including helping agencies (doctors, hospitals, fire, police, transport etc.) 4. Help To identify, various kinds of possible hazards, their places, potential and damaging capacity 5. Planning reduces the thinking time for necessary steps at the time of accident 6. Planning helps to contain the incident and to minimise the loss 199.
Roles & Responsibility
200.
In Case of Fire and toxic release:
1. All persons are responsible to report section in charge about details of any incident of fire or any toxic release (slight, minor, major etc.) The section-in-charge will work as incident controller. 2. The incident controller shall a. Order the 'Fire Team' or “Gas team� to control it with all its available means. b. Assess the nature of fire and report in details to the site main controller. 3. The site main controller shall a. Take all actions to remove/control the fire or reduce the toxic effect. b. Ask Gas Team and fire -fighting services of the factory for necessary control and evacuation in the plant c. Take help of mutual aid services to fight fire, if it is uncontrolled. d. Report the off- site fire fighting services for help and action, e. Report to control room for necessary action, f. Co-ordinate with offsite fire services to control the fire. g. Operate alarm to warn the surrounding people before it is likely to effect, 4. Traffic control, rehabilitation and evacuation team (TERT) - To control the traffic toward and near places of disaster to maintain law and order. 5. Utility and Engineering services Team (UEST) - To check , regulate, divert the flow of electricity, water, petrol, gas for the purpose of cutting of sources of danger. 6. Medical help team- To give medical help to all injured person as soon as possible 201. 202.
Q) Safety Audit?
203. 1. It is a critical examination of all or part, of a total operating system with relevance to safety and to suggest improvements and up gradation. 2. A safety audit is intended to measure the effectiveness of a company's safety programs in every respect. 3. The objectives should be clearly defined such as-' 204. 1. To carry out a systematic and critical appraisal of all potential hazards involving personnel, plant, services and methods of operation. 205.
2. To ensure that the occupational health and safety standards fully satisfy the legal requirements and those of the company's written safety policies, objectives and programs. 206. 4. The word 'safety audit' is also used for 'safety inspection' intended for 207. 1. 2. 3. 4. 5.
Identification of possible loss situations. Measurement of the potential losses associated with these risks. Selection of methods to minimize the losses. Implementation of the selected methods within the company and Monitoring of the result and suggesting further improvement based on review.
208. 209.
Q) Runaway Reaction?
210. 1. A runaway reaction is a chemical reaction over which control has been lost. 2. It continues to accelerate in reaction speed until it either runs out of reactants or the vessel containing it overpressures, losing containment – frequently with high risk of injury and equipment damage. 3. Is the reaction phenomenon when the reaction rat very fast at uncontrollable leading to situation of overpressure of reaction vessels and causes explosion. 4. Run away reaction are mostly encountered for exothermic reaction and its promoted by high concentration of reactant, high pressure and high temperature 5. Presence of impurities by product and catalyst increase the reaction rate. 6. Runaway reaction can be controlled by dumping large quantity of water for rapid dilution or limiting the quantity of reactant or reactable material in the process. 7. Limiting the pressure and temperature. 8. Explosion due to runaway reaction can be reduced by providing, safety valve, rupture disc, automatic shutdown 211.
Fire & Explosion
212.
Q) Explain BLEVE and briefly discussed one of the industrial accident
happened due to BLEVE? 8M 213.
Q) Explain BLEVE? How it is happened? 4M
214. 215.
BLEVE:
1. Boiling liquid expanding vapour explosion (BLEVE), also referred as a fireball, 2. It is the combination of fire and explosion with an intense radiant heat emission within a relatively short time interval. 3. When a tank or pressure vessel containing liquid or liquefied gas above its boiling point (so heated) fails or ruptures the contents release as a turbulent mixture of liquid and gas, expanding rapidly and dispersing in air as a cloud.
4.
When this cloud is ignited, a fireball occurs causing enormous heat radiation
intensity within a few seconds. 5. This heat is sufficient to cause severe skin burns and deaths within a few hundred metres depending on the mass of the gas involved. 6. A BLEVE involving a 50- tonne propane tank can cause '"third-degree burn at @ 200 MT and blisters at @ 400 MT 216.
Causes of BLEVE:
1. Road/rail accident to a tank car/wagon or due to weakening of structure can cause a BLEVE 2. Physical impact on an overstressed vessel/tank can cause a BLEVE. 3. external fire near the storage vessel causing heating of the contents and pressure build-up 4. liquid or liquefied gas above its boiling point (so heated) fails or ruptures 5. Failure of pressure relief valve, result in build up the pressure inside 217.
ACCIDENT:
1. The Feyzin Disaster occurred in a refinery near the town of Feyzin, 10 kilometres south of Lyon, France on 4 January 1966. 2. An LPG spill occurred when an operator was draining water from a 1,200mÂł pressurised propane tank. 3. The resultant cloud of propane vapour spread, until it was ignited by a car on an adjoining road. 4. The pool of propane in the bund caused the storage tank to be engulfed in flames, which produced a Boiling Liquid Expanding Vapour Explosion (BLEVE) when the tank ruptured. 5. This resulted in a fireball which killed and injured firemen and spectators. 6. Flying missiles broke the legs of an adjacent sphere which later BLEVE'd. 7. Three further spheres toppled due to the collapse of support legs which were not adequately fire protected. 8. These vessels ruptured but did not explode. 9. A number of petrol and crude oil tanks also caught fire. 10. The conflagration took 48 hours to bring under control. 11. This incident resulted in the deaths of 18 people, the injury of 81 and extensive damage to the site. 218.
Q) Explain the fire detector and alarm system used in chemical
industry? 1. Various types of detectors are available operating on principles of thermal expansion, thermoelectric sensitivity, thermo conductivity or photosensitivity to detect presence of smoke, increase in temperature, light intensity or total radiation. 2. Their types are :
3. 4. 5. 6.
Thermal expansion detectors. Radiant energy detectors. Light interference detectors and Ionisation detectors. They should be properly located depending upon their range. They simply give alarm and cannot extinguish fire. They make us alert for fire fighting. Though fire detection and alarm systems are separate systems but Both are
interconnected Therefore they are considered together. 7. Two main functions of any fire detection system are To give alarm to start up extinguishing procedure, and To give early warning to area occupants to escape. 8. It is wrong to speak 'fire detectors'. Actually they detect sensible heat, smoke density or flame radiation to operate before actual fire occurs. 9. Selection of the type of detector is important For example, Low risk areas need thermal detectors, A ware house may have infrared and ionisation detectors and A computer area requires ionisation detectors. 9. Location and spacing should be determined to obtain the earliest possible warning. 10. Sensitivity, reliability, maintainability and stability are important factors for selection. 11. Thermal detectors are of Fixed temperature detectors, rate-compensated thermal detectors, rate of rise thermal detectors, line thermal detectors 12. Smoke detectors are of photoelectric type and are of two classes - The beam photoelectric or reflected beam photoelectric detectors. 13. Flame detectors are of infrared (IR) or ultraviolet (UV) type. 14. Ionisation (combustion products) detectors are the single chamber or dual chamber ionisation detector and the low-voltage ionisation detector. 219.
Fire Alarm System
1. Fire Alarm system may be separate to run manually or connected with fire detectors and operable automatically. 2. All workers must be made aware of the sound pattern and its meaning. 3. Fire alarm sound should be distinguishable from other sound m that area. 4. It should be clearly audible to all facility personnel. 5. Sound for beginning of fire and end of fire should be kept different. 220.
Q) Fire Load Determination?
1. After fire detection and alarm system and before fire suppression or extinguishing system, it is necessary to know the fire load so that based on that, amount of fire extinguishing system can be designed and number of fixed and portable fire extinguishers can be calculated.
2. Fire load is the concentration or amount of combustible material in a building per sq. mt. of floor area. 3. It is defined as the amount of heat released in kilo calories by the fuel per square meter area of the premises. 4. Fire loads are useful to calculate the water requirement to quench the fire, as when water comes in contact with burning surface it absorbs heat. 5. 1 cc of water absorbs 1 cal of heat when the' temperature is raised by 1°C. 6. The fact should also be considered that all the fuel does not burn at a time and all the water does not absorb heat as it flows away. 7. Fire loads are calculated to assess potentiality of fire hazard, need of amount of fire prevention and protection systems (e.g. water or other agent) and amount of 8.
premiums required for fire insurance. Fire load classification is as follows: 221.
Low fire load
-
Less than 1 lakh B.Th. U.
222.
Moderate fire load
-
Between 1 to 2 lakhs B.Th. U.
223.
Higher fire load
-
More than 2 lakhs B.Th. U
224. 225.
Q) Fire Extinguishers? 4M
1. Mainly three methods are used in all such systems : 226. (1) Starvation or isolation i.e. shutting off or preventing the flow of fuel and blanketing the fire surface with form 227. (2) Cooling by application of water, foam or dry chemical powder and 228. (3) Smothering by applying inert gas (to reduce oxygen), steam, dry chemicals 229. 2. Two types of extinguishers are used, portable and fixed. 230. 231.
Portable Fire Extinguishers Soda Acid (Water Type) Extinguisher Foam Extinguisher CO2 (Compressed gas) Extinguisher Dry Chemical Powder (DCP) Extinguisher Halon Gas Extinguisher (Halon Alternatives) 232.
233.
Fixed Fire Extinguishers Fire Hydrants Automatic Water Sprinklers Water Spray System Foam System Carbon dioxide systems Dry Chemical Powder (DCP) Inert Gas System
234. 235.
Steam System
Q) Sprinkler system? 4M
1. They are of six types.
Wet pipe dry pipe pre-action
deluge combined dry pipe and
Pre-action and sprinklers for limited water supply system. 2. Automatic alarms operated by the flow of water should be a part of sprinkler 3. 4. 5. 6.
installation. Such an alarm may be connected to a central fire station. The sprinklers should be regularly checked to avoid their failure to work. Automatic sprinklers are most efficient and widely used. Its basic function is to spray water automatically to a fire, the system can also work as a fire alarm. This can be done by installing an electrical water flow alarm
switch in each main riser pipe. 7. Sprinklers should be selected on the basis of temperature rating and occupancy. 8. In deluge system, water is admitted to sprinklers that are open at all times. 9. Deluge valves (water supply valves) can be operated manually or automatically by an automatic detection system. 10. Maintenance and inspection of water supply valves, system piping for obstruction, nozzles and water supply tests etc. are necessary.
Q) Explain the DCP fire extinguishers with neat sketches? Mention for which type of fires it is used?
1. This can be used on any class of fire. Therefore it is known as 'universal type 2. 3. 4. 5.
extinguisher'. It is generally used on fire of flammable liquid. It is not effective on fire of benzene, ether, EO and CS2 For metal fire, special powder extinguishers are available. 1, 2, 5 and 10 kg extinguishers in cylinders and 68 kg in wheel models are
6. 7. 8. 9.
available. A 10 kg cylinder is consumed within 12 to 15 seconds and its range is 3 to 6 mt. A 68 kg cylinder is consumed within I to 1.5 minute and its range is 6 to 8 mt. Both should be checked at 3 months interval. By standing 6 to 8 mt near the fire, the cylinder is shacked twice by turning 180°, a safety clip is removed and plunger is pressed or struck so that CO, bottle breaks
and it throws dry chemicals out. 10. The dry powder blankets the burning surface, stops O2, contact and CO2, coming out also diminishes 0 proportion. 11. Therefore fire is controlled by double action.
Q) What is Dow fire and explosion index? How it is calculated? How the information is useful to the management to protect the assets?
Fire and Explosion index
1. This is a method of identifying and ranking of hazards present in a process plant. 2. It was developed by Dow Chemical, USA and is usually known as Dow Fire and Explosion Index 3. The most famous and widely used hazard index is the Dow Index developed by the Dow Chemical Company of USA since 1964. 4. In the first three editions the methods of determining the Fire and Explosion Index (F & El) were developed and in the fourth edition, the method of calculating Maximum Probable Property Damage (MPPD) from the F & El was suggested and a Toxicity Index (n) were introduced. 5. The index provides weightage for inventory, flammability, reactivity, toxicity and hazards due to reaction exotherm, operating condition, corrosivity, plant drainage, access, rotating equipment, leaky joints etc.
Calculation of Fire and Explosion Index
1. Identify any Process Units that are considered pertinent to the process 2. Determine the Material Factors (MF) for each process unit. It can be calculated from flammability and reactivity 3. Calculate F1 , general process hazards 4. Calculate F2, Special process hazards 5. Determine unit hazards factor F3=(1+F1)X(1+F2 )
6. Determine Fire and explosion index, F&EI=Material Factor X F3
Material Factor
1. Material Factor (MF) is the basic starting value in the computation of the F & El and other risk analysis values. 2. The MF is a number in the range from 1 to 40 and higher number indicates higher hazard. MF and Heat of combustion HC 3. Higher MF indicates high hazard potential and higher H C. Indicates high heat generation while burning, which in turn, indicates more quantity of fire fighting material (e.g. water, foam, DCP etc.) and equipment.
Toxicity Index
1. The Toxicity Index is used to evaluate process exposure level for toxicity hazard and is defined as – TI = (TH+TS) (1+P+S) 100 Where, Th = Toxicity factor TS= Supplement for mac value P the total GPH (General Process Hazards) penalties used and S the total SPH (Special Process Hazards) penalties used.
Importance information to protect Asset
1. MOND Index is an extended Dow Index based on the similar methodology with an useful extension e.g. to estimate fire load. 2. Fire loads are help to calculate amount of premiums required for fire insurance. 3. Determine the Rupee value of all equipment within the Area of Exposure. 4. This value is used to obtain the Base maximum Probable Property Damage (Base MPPD). 5. The Base MPPD can be reduced to an actual MPPD by applying various Credit 6. Actual MPPD is used to obtain MPDO, from which Business Interruption (BI) can be calculated.
Q) Importance of DOW Index?
1. To identifying and ranking of hazards present in a process plant. 2. Qualify the expected damage due to fire, explosion or toxicity 3. Identify the equipment that would create or escalate an accident and 4. Communicate such risk potential to management to take necessary remedial measure
5. The index provides weightage for inventory, flammability, reactivity, toxicity and hazards due to reaction exotherm, operating condition, corrosivity, plant drainage, access, rotating equipment, leaky joints etc. 6. to estimate fire load 7. To calculate maximum probable property damage (MPPD) and maximum possible days outage (MPDO) 8. Business Interruption (BI) can be calculated.
Q) Deflagration and detonation?
Deflagration It is an explosion with a resulting
shock
wave
resulting
the
than the speed of sound in
speed
of
sound
in
unreacted medium.
Deflagration is very rapid
Detonation
of explosive as a surface
decomposition
phenomenon.
explosive accompanied by
It
may
be
initiated
by
self-propagating
high
of
an
pressure-
temperature wave It may be initiated
by
contact of a flame or spark
mechanical impact, friction
but may be caused by
or heat.
impact or friction. It is a characteristic of low
It is a characteristic of high explosives
Less Destructive
A detonation generates high destructive
Peak pressure caused by a deflagration
in
a
closed
80 kPa (8 bar), A deflagration can turn into
and
is
more
than
a
deflagration. Peak pressure in case of detonation it easily reaches
vessel can reach up to 70
extremely
rapid,
pressure
is
auto combustion of particles
explosives.
wave'
moving at a speed more
a
shock
moving at a speed less than unreacted medium.
Detonation It is an explosion with a
up to 200 kPa (20 bar).
Detonation usually occurs
a detonation while travelling
at well below the upper
through a long pipe
explosive limits.
Q) Vapour cloud Explosion?
4M Q) Chemistry of Fire
4M Q) What are causes of industrial fire and its prevention?
8M Q) Fire Triangle?
4M Q) Classification of fire and write down the causes of fire?
8M Q) What is fire? Explain classification and media used for fighting?
8M Q) Describe the use of fire hydrant system? 4M