IS-203

CHEMICAL SAFETY IN INDUSTRY

2022
State whether the following Statements are True or False (Any Ten)
i) High efficiency in mass transfer and heat transfer cause less heat hazards in
continuous process. False
ii) A MSDS does not contain information on the potential hazards of chemical False
iii) Mixture of premixed and non premixed flammable gas is the ideal condition for Fire
Ball creation.
iv) An ignition source is not needed to initiate the explosion in vapour cloud explosion.
False
v) Preparation of Hazardous chemical receiving SOP for each chemical as it is applicable
is not mandatory False
vi) A batch process in chemical Industry generally runs in very long time direction . True
vii) Transportation, handling and storing of chemicals are directly related to the chemical
hazard in the industry. True
viii) Dust is not a hazard in chemical industry False
ix) When a flammable vapour is released in open air it mix with air and may form a
flammable vapour cloud. True
x) In as continuous process, the raw material and the product is charged and discharged
simultaneously during the whole period of processing. True
xi) LPG is treated as a class –A hazardous product materials. True
xii) A reducing flame is a flame with insufficient oxygen. True
xiii) The most common exposure route to chemicals in the work environment is through
inhalation. True
xiv) Do not store chemicals alphabetically except within a grouping of compatible
chemicals. True
Fill in the blanks (any ten) :-
i) If a flame has too much oxygen, an oxidizing flames produced.
ii) A numerical "Fire and Explosion Index" is calculated based on the nature of the process
and the properties of the process materials.
iii) In pipeline transfer booster stations are pumping stations placed along the pipeline.
iv) In case of emergency, fire siren shall be wailing sound for 2 minutes.
v) An incident causing great and sudden damage is called as disasters.
vi) Pipeline transportation is the long-distance transportation of water, wastes, minerals,
chemicals, and industrial gases,
vii) A pool fire produces a type of turbulent non-premixed flame.
viii) A Material Safety Data Sheet is a document that contains information on the potential
hazards
ix) In some batch process operation old catalysts are...........................................
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x) The containers that hold liquids or gases at high pressure are called pressure vessel
xi) A flash fire produces..........................flame.
xii) An incident shall be treated as 'Major' if the loss occurs above Rs 20 Lac.
xiii) Gaseous chemicals are stored by liquefying those by high pressure and cooling are
called...................................storage.
xiv) Mock drill for Off-site (Level-III) emergency shall be carried once in 3and 12 months.
Note :- Mock drill for On site (Level –I or II) and Off site (Level-III) emergency shall be carried
once in three months and twelve months respectively in accordance with Typical Mock Drill
Reporting format provided in Annexure -3.
xv) The Off-site emergency exercise may be carried out in coordination with the concerned
District Authority
Answer the following questions (any five):
i) Write about pressurized storage vessel.
Ans :- A pressure vessel is a closed container designed to hold gases or liquids at a pressure
substantially higher or lower than the ambient pressure. Examples include glassware, autoclaves,
compressed gas cylinders, compressors (including refrigeration), vacuum chambers and custom
designed laboratory vessels.
Pressure vessels, autoclaves and steam sterilizers operating at pressures greater than 15 pounds
per square inch gauge (psig) and larger than five cubic feet (ft3) volume fall within the
Washington State Boiler and Pressure Vessel Code. As such, they have strict requirements for
design, testing and approval.

ii) Safety in handling of chemicals,

Ans :- 1. Study and identify chemical hazards using material safety data sheet (MSDS) and a
system of
classification, packaging and labelling should be developed.
2. Select safer technology.
3. Select safer sitting of chemical industry for minimum loss to men, material, environment etc.
4. Design and construct the factory with all safety precautions from the very beginning.
5. Workplace hazards inside the factory should be controlled by good engineering controls, safe
work methods or operating procedure and using personal protective equipment.
6. All requisite safety devices, fittings, instruments, equipment, machines etc., must be provided
and well maintained.
7. Workers must be properly trained for safe operation of the plant and their role in emergency
planning and control.
8. Safe transportation and handling of hazardous chemicals within and out-side factory premises.
9. Safe disposal of hazardous wastes within and outside factory premises.
10. Well monitoring and control of hazardous substances at work places and of occupational
illeffects and diseases by pre and periodical medical examinations of the workers.
iii) What is the meaning of BLEVE (Repeated)
iv) Explain Flash. (Repeated)
v) Write uses of MSDS
Ans :- A material safety data sheet (MSDS) is a form with data regarding the properties of a
particular substance. An important component of product stewardship and workplace safety, it is
intended to provide workers and emergency personnel with procedures for handling or working
with that substance in a safe manner, and includes information such as physical data (melting
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point, boiling point, flash point, etc.), toxicity, health effects, first aid, reactivity, storage, disposal,
protective equipment, and spill-handling procedures. MSDS formats can vary from source to
source within a country depending on national requirements. In India it is a statutory
requirement under R-41 D of West Bengal Factories Rules, 1958 as amended.
vi) Describe meaning of HAZOP in short(Repeated)
vii) Write note on Auto ignition point.
Ans :- A material's auto ignition or ignition temperature is the temperature at which a material
self-ignites without any obvious sources of ignition, such as a spark or flame. Most common
flammable and combustible liquids have autoignition temperatures in the range of 300°C (572°F)
to 550°C (1022°F).
Answer the following questions (any four):
i) What is Runway Reaction? State its precaution, preventive and control measures.
Ans :- RUNAWAY REACTIONS:
During the manufacture of a chemical, raw materials react together to give the product. Such a
chemical process often releases energy, in the form of heat, and the reaction is described as
exothermic. In chemical engineering, thermal runaway is a process by which an exothermic
reaction goes out of control, often resulting in an explosion. It is also known as a "runaway
reaction.
Thermal runaway:
An exothermic reaction can lead to thermal runaway, which begins when the heat produced by
the reaction exceeds the heat removed. The surplus heat raises the temperature of the reaction
mass, which causes the rate of reaction to increase. This in turn accelerates the rate of heat
production. An approximate rule of thumb suggests that reaction rate - and hence the rate of heat
generation
- doubles with every 10°C rise in temperature.
Examples
• It has contributed to industrial chemical accidents, most notably the 1947 Texas City disaster
from overheated
ammonium nitrate in a ship's hold.
• The disastrous release of a large volume of methyl isocyanate gas from a Union Carbide plant in
Bhopal, India in 1984, thermal runaway reaction was also one of the major cause of the disaster.
• Thermal runaway is also a concern in hydrocracking, an oil refinery process.
• Thermal runaway may result from exothermic side reaction(s) that begin at higher
temperatures, following an initial accidental overheating of the reaction mixture. This scenario
was behind the Seveso disaster, where thermal runaway heated a reaction to temperatures such
that in addition to the intended 2,4,5- trichlorophenol, poisonous 2,3,7,8- tetrachlorodibenzo-p-
dioxin-TCDD was also produced, and was vented into the environment after the reactor's rupture
disk burst.
Control, precaution and prevention of occurrence of runaway reactions
i) Chemical process risk assessment
ii) Evaluating reaction hazards
iii) Safety measures
• Safe operation may be ensured by using the following ways along with other:
• Inherently safer methods, which eliminate or reduce the hazard;
• Process control, which prevents a runaway reaction occurring; and
• Protective measures, which limit the consequences of a runaway
• Designing the plant to contain the maximum pressure-fit emergency relief vents and ensure
vented material goes to a safe place;
• Crash cooling the reaction mixture if it moves outside set limits;
• Adding a reaction inhibitor to kill the reaction and prevent runaway; or,
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• Dumping the reaction into a quenching fluid.
iv) Selecting the basis of safety-Whatever methods are chosen, they must cater
for all cases that can foresee ably occur and reduce the risk of runaway to a level
that is as low as reasonably practicable.
v) Safety management-
– operating and emergency procedures;
– consultation with employees;
– training and supervision of operators;
– maintenance of equipment; and
– control of modifications.
vi) Emergency planning and rehearsal-Preparation of emergency plan and adoption has
become a statutory requirement to prevent and control ill effects of runaway reactions. Properly
planning with regular rehearsal has been found very use ful.
ii) Discuss the safe work procedure in maintenance of pipelines. What are the precautions
to be taken in breaking pipelines?
Ans :- Following safe work procedure in maintenance of pipelines
1. Inspection by an experienced engineer for assessment of work.
2. written work permit specifying precautions to be observed and procedure to be followed.
3. The section of the pipeline shall be isolated, drained and purged with inert gas or steam or kept
filled with water or treatment approved by the CC.
4. Work of cutting or welding to be carried out by an experienced person in accordance with the
permit
5. Only mechanical cutters shall be used for cutting the pipeline or any connection thereof unless
it has been purged with an inert gas.
6. Separation of pipeline or valve fitted to it only after providing electrical bond between the
parts, to be separated and the bond shall not be broken till the parts have been rejoined.
7. Reuse of the repaired section only after hydrotest as stated .
Following precautions are necessary while opening or breaking any pipeline :
1. Prepare work permit. Tag the joint or portion to be broken.
2. Close or lock the isolation valves to stop flow in the line to be opened. Isolate the area.
3. Stop pump and motor. Remove fuse so that motor cannot be started.
4. Drain, vent and cool the line completely. See that the pressure is zero and the pipe is cool.
5. Wear PPE like hand gloves, face shield, apron, respirator etc. depending on chemical . Keep fire
extinguishers ready.
6. Support the line on both the sides of joint. If it can fall, hold it by a lifting machine. Flange nuts
and bolts should be opened slowly. A temporary flange guard should be put so as to protect from
splashes or dripping. First the farthest nut-bolt should be loosened so that splash if any, may not
come toward the body. Dripping, if any, should be allowed fully. Then the adjacent nut bolts
should be opened. To separate flanges, a metal wedge may be used if necessary. Final bolt will be
opened only after completion of dripping. Spark should be avoided.
7. After removing choking by scrapping, digging or drilling, the removed section of the line, valve
etc. should be decontaminated by water, air or purging inert gas. If this is not possible, it should
be tagged with warning, indicating the contaminant.
8. Use stable platform. Working by sitting on other pipelines, ladder or structure is risky.
9. Safety shower, running water hose, fire extinguisher, absorbent etc. should be kept ready for.
use.
10. More precautions should be taken while opening dead lines or pipes whose content is not
known.
11. Direct cutting by hacksaw or gas flame without knowing the content is hazardous. Flammable,
corrosive or toxic content must always be removed first.

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iii) Discuss how you will assess DOW Index, Make a Risk Analysis of chemical plant
operation.
Ans :- Various hazard indices have been developed to (1) Qualify the expected damage due to fire,
explosion or toxicity (2) Identify the equipment that would create or escalate an accident and (3)
Communicate such risk potential to management to take necessary remedial measures e.g.
increasing separation distance, erecting a blast wall or fireproof construction and revision of fire
fighting and gas control facilities. '
The most famous and widely used hazard index is the Dow Index developed by the Dow
Chemical Company of USA since 1964. The MOND Index is an extended Dow Index based on the
similar methodology with an useful extension e.g. to estimate fire load of an area and a unit
toxicity index. 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) was introduced.
For details the Company's Guide has to be referred.
To develop an F&EI and risk analysis summary, we need -
1. An accurate plot plan of the plant.
2. A process flowsheet.
3. An F& El Hazard Classification Guide.
4. An F& El Form.
5. An Unit Analysis Summary.
6. A Plant Risk Analysis Summary, and
7. A cost data for the installed process equipment under study.
schematic diagram of procedure to calculate F & El, MPPD, MPDO (Maximum Probable Days
Outage) and BI (Business Interruption loss) is shown below
As revealed from the figure, the procedure for assessment is summarized as under
1. Identify on the plot plan any Process Units that are considered pertinent to the process and
that
would have the greatest impact on the magnitude of a fire or explosion.
2. Determine the Material Factors (MF) for each process unit. It can be calculated from
flammability and reactivity, or from its ready table (some figures are given below).
3. Evaluate each of the contributing hazard factors listed on the F & El Form, under 'General
Process Hazards' and 'Special Process Hazards' and apply the appropriate penalties. This will give
F1 and F2.
4. Unit hazard factor F3 = F1 x F2. This gives the degree of hazard exposure of the process unit.
From the chart, using unit hazard factor with the MF to determine Damage Factor (DF) which
represents the degree of loss exposure.
5. F & El = MF x F,. From the chart, by using F & El, Area (radius) of Exposure surrounding the
process unit can be determined.
6. Determine the Rupee value of all equipment within the Area of Exposure. This value is used to
obtain the Base maximum Probable Property Damage (Base MPPD).
7. The Base MPPD can be reduced to an actual MPPD by applying various Credit Factors and/ or
'by relocating certain high value equipment outside the Area of Exposure.
8. Actual MPPD is used to obtain MPDO, from which Business Interruption (BI) can be calculated.

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iv) Discuss the safety measures in Insecticide and pesticide manufacturing plant Write
about the engineering control to prevent toxic release,
Ans : - Safety measures in Insecticide manufacturing plant :-
Every container package should be of the approved type. A leaflet should be put inside
containing particulars about the plant disease, insects, animals or weeds for which it is to be
applied, manner of application, symptoms of poisoning, safety measures and first-aid treatment
necessary, antidote, decontamination or safe disposal procedure, storage and handling
precautions, effect on skin, nose eye, throat etc. and common name of the insecticide (R. 18).
In labelling, warning and cautionary statement should be included.
(1) For category-I (Extremely toxic) insecticides, the symbol of a skull and cross-bones and the
word 'POISON' should be printed in red. Statement "Keep out of the reach of children and if
swallowed or if symptoms of poisoning occur call physician immediately" should be added.
(2) For category II (Highly toxic) insecticides, the word TOISON' in red and statement "Keep out
of the reach of children" should be printed.
(3) For category III (moderately toxic) the word 'DANGER' arid statement "Keep out of the reach
of children".
(4) For category IV (Slightly toxic) the word 'CAUTION' should be mentioned.
Protective Equipment and other Facilities for Workers :
All persons engaged in handling, dealing or otherwise coming in contact with insecticides during
manufacture/formulation or spraying shall be medically examined before employment and then
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periodically once in a quarter by a qualified doctor who is aware of risks of pesticides .For
persons working with organ phosphorous or carbonate compound, their blood cholinesterase
level shall be measured monthly. The blood residue estimation shall be done yearly
of persons working with organo-chlorine compound. Any person showing symptoms of poisoning
shall be immediately examined and given proper treatment.
First-aid treatment shall always be given before the physician is called. IS 4015 part I and II shall
be followed in addition to any other books on the subject. The workers shall be educated
regarding effects of poisoning and the first-aid treatment to be given.
Protective clothing which shall be washable (to remove toxic exposure) and not allowing
penetration by insecticide shall be given to workers. A complete suit shall consist
(a) Protective outer garment/overalls/ hood/hat,
(b) rubber gloves extending half-way up to fore-arm
(c) dust-proof goggles and
(d) boots.
For prevention of inhalation of toxic dusts, vapours or gases, the workers shall use
(a) chemical cartridge respirator,
(b) supplied air respirator .
(c) demand flow type respirator
(d) full or half face gas
mask with canister as per requirement. In no case the exposure in air should exceed the
maximum permissible level.
Sufficient stocks of first-aid tools, equipment, antidotes, medicines etc. should be kept.
The workers shall be trained for safety precautions and use of safety equipment.
The packages and surplus materials shall be safely washed and disposed to prevent pollution.
The packages shall not be left outside to prevent re-use. They shall be broken and buried away
from habitation.
safety measures in pesticide manufacturing plant :-
1. Pesticides are generally poisonous substances.
2. Therefore in rooms where these are handled(a) do not chew, eat, drink Or smoke; keep food or
drink away from pesticides. (b) use the protective wear supplied e.g. gloves, aprons, clothes,
boots, etc.
3. Before meals or when any part of the body has come in contact with the pesticides, wash with
soap and water.
4. Before leaving the factory, take a bath and change your clothing.
5. Do not use any container that has contained a pesticide as a pot for food or drink.
6. Do not handle any pesticide with bare hands; use a handled scoop.
7. Avoid spilling of any pesticide on body, floor or table.
8. Maintain scrupulous cleanliness of body and clothing and of your surroundings.
9. In case of sickness like nausea, vomiting or giddiness, inform the manager who will make
necessary arrangements for treatment.
Pesticides and agrochemicals enter into the body through inhalation, ingestion or skin
absorption. They are classified as toxic, harmful, corrosive, irritant, flammable, explosive or
oxidizing. Toxicity is mostly denoted by LD,, or LC,, values. All agrochemicals should be labelled,
transported safely and correctly stored in a room (locked and cool). Containers should be opened
only after wearing correct respirator (positive air pressure), neoprene or plastic hand gloves,
aprons, boots etc. Protective clothing are always essential while handling pesticides. Inhalation of
vapour should be avoided. Contact with skin, eyes and clothing should also be avoided.
Contaminated clothing should be immediately changed, the entire body .should be thoroughly
washed with soap and water. After working with pesticides, shower bath should be taken and
clothing should be changed. Contaminated equipment should be cleaned with soap or soda ash.
v) Describe the components of a pipeline. What is pipeline & instrumentation diagram?
Sate the safety devices of pipeline,
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Ans :- A pipeline is a system that consists of pipes, fittings (valves and joints), pumps
(compressors or blowers in the case of gas pipelines), booster stations (i.e., intermediate
pumping stations placed along the pipeline to house pumps or compressors), storage facilities
connected to the pipe, intake and outlet structures, flowmeters and other sensors, automatic
control equipment including computers, and a communication system that uses microwaves,
cables, and satellites. Booster stations are needed only for long pipelines that require more than
one pumping station. The distance between booster stations for large pipelines is on the order of
50 miles. Special pipelines that transport cryogenic fluids, such as liquefied natural gas and
liquid carbon dioxide, must have refrigeration systems to keep the fluid in the pipe below critical
temperatures.
A piping and instrumentation diagram (P&ID or PID) is a detailed diagram in the process
industry which shows the piping and process equipment together with the instrumentation and
control devices.
A piping and instrumentation diagram (P&ID) is defined as follows:

1. A diagram which shows the interconnection of process equipment and the

instrumentation used to control the process. In the process industry, a standard set of
symbols is used to prepare drawings of processes. The instrument symbols used in these
drawings are generally based on International Society of Automation (ISA) Standard S5.1
2. The primary schematic drawing used for laying out a process control installation.
They usually contain the following information:

 Mechanical equipment, including:

o Pressure vessels, columns, tanks, pumps, compressors, heat
exchangers, furnaces, wellheads, fans, cooling towers, turbo-expanders, pig traps (see
'symbols' below)
o Bursting discs, restriction orifices, strainers and filters, steam traps, moisture traps, sight-
glasses, silencers, flares and vents, flame arrestors, vortex breakers, eductors

 Process piping, sizes and identification, including:

o Pipe classes and piping line numbers
o Flow directions
o Interconnections references
o Permanent start-up, flush and bypass lines
o Pipelines and flowlines
o Blinds and spectacle blinds
o Insulation and heat tracing
 Process control instrumentation and designation (names, numbers, unique tag identifiers),
including:
o Valves and their types and identifications (e.g. isolation, shutoff, relief and safety valves,
valve interlocks)
o Control inputs and outputs (sensors and final elements, interlocks)
o Miscellaneous - vents, drains, flanges, special fittings, sampling lines, reducers and swages
 Interfaces for class changes
 Computer control system
 Identification of components and subsystems delivered by others

safety devices of pipeline

 Corrosion Protection
 Materials
 Welds
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  Valves
 Operating Pressure
 Monitoring
 Leak Detection
 Internal Inspections
 Integrity Management
vi) Discuss about the safe entry procedure to confined spaces, Describe the inspection
techniques of isolated storages.
Ans :- safe entry procedure to confined spaces :-
The area for which the confined space entry will occur, is responsible to ensure that all
preparations are in place for the safe entry of any worker.
 Ensure workers involved in the confined space are trained in the conditions of entry and the
nature of any hazards they may be exposed to.
 Ensure the appropriate PPE is available and in good working order.
 Ensure rescue procedures, equipment and trained rescue personnel are in place.
 Ensure a Confined Space “Safe Entry Tag” is completed.
 Identify the “Class” of Confined Space.
 Assign a safety watch person on the outside of the tank.
 Periodically check the confined space entry jobs to ensure all Health & Safety procedures are
being followed.
 To immediately shut down any unsafe confined space entry job.
 The worker prior to entering the confined space will ensure that all necessary precautions and
procedures are in place to their satisfaction and then sign the Confined Space “Safe Entry Tag”
.  Will wear all Personal Protective Equipment assigned to them, to ensure their safety and
health according to the hazards of the confined space job.
 Will inspect and use equipment and tools required to do the jobs inside the confined space,
according to safe work practices and procedures.
 Will monitor conditions inside the confined space and if conditions should change inside that
are not accounted for on the “Safe Entry Tag” they will discontinue the work and exit the confined
space until the new hazards have been addressed.
The inspection techniques of isolated storages
1. Identifying the work area as a confined space.
2. Conduct a hazard assessment of the confined space.
3. Classify the confined space as an A, B, or C confined space.
4. Post the confined space classification at/near the confined space.
5. Train the workers in confined space entry procedures and review the hazard assessment for
the confined space.
6. Prepare the confined space for entry by purging or ventilating the tank if there are hazardous
atmosphere toxins, lack of oxygen or oxygen enriched environment. Note; Oxygen content must
be between 19.5% and 21.4%.
7. Complete a “Safe Entry Tag” that will put into action Gas tests, Safety Procedures, Equipment to
be used i.e. (ventilation, electrical with (GFI), tools), Personnel Protective Equipment, Potential
hazards, Location of vessel/tank, Description of work, Lockout required, Safety watch required,

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Communication system to be used, Rescue equipment and personnel in-place, Duration of
confined work, Date and time of entry, Names of all workers entering the confined space,
Signature of qualified “Safe Entry Tag” issuer, Safety watch and the signature of a qualified
worker accepting the “Safe Entry Tag”.
8. Once all criteria on the “Safe Entry Tag” has been completed, the worker(s) can enter the
confined space.
9. Once the confined space work has been completed, the “Safe Entry Tag” issuer will inspect the
confined space to ensure all workers, tools and equipment have been removed.
10.The “Safe Entry Tag” issuer will then sign-off on the tag, that this confined space work has
been completed.
11. All completed “Safe Entry Tags” will be filed and kept by month and year.
vi) Discuss the safety in batch process operation and continuous process operation in
chemical industry.
Ans :- Generally in a chemical plant processes are classified as batch processes or continuous
processes or their combination. In a batch process relatively more man-power is required, the
workers are exposed to hazards more frequently and process automation and instrumentation
are possible only to a limited extent. A continuous process is carried out in a closed vessel or
circuit and good automation and instrumentation are possible. Many processes are operated at
high pressure and high temperature (as incase of petroleum and petrochemical industry) for
which automatic warning, monitoring and controlling devices are desired. Pressure and
temperature should be properly controlled by cooling and safety devices. Flammable, explosives
and solvent distillation processes should be carried out under inert atmosphere or vacuum and
toxic processes should be connected with appropriate scrubbers and neutralisers.
Study all unit processes arid unit operations with complete reaction documents i.e. all reaction
data of intermittent behaviour as well as escaping behaviour out of the controlled parameters.
This requires precise laboratory study and much details of side reactions, unwanted runaway
reaction, generation of any flammable or toxic vapour, fumes, gas etc. or generation of abnormal
pressure, temperature, expansion, contraction etc. at any stage of the process in control or out of
control and adversely affecting the people or environment. Based on this, all necessary safety
measures must be kept ready and provided to keep the reaction in control and to control again in
the event of their going out of control also. Processes of exothermic and high pressure reaction,
solvent distillation, distillation of toxic substance, polymerisation/chain reaction, , gas
generation, filling etc., petroleum processing, autocatalytic reaction, decomposition, undesired
reaction with other media, operating in or near explosive range, process of combustible material,
process of toxic material , dust/ fume/gas process and process difficult to control need much
attention.
vi) Describe the inspection techniques of a Reaction Vessel, Prepare a checklist for
inspection of compressor.
Ans : - Inspections are a crucial part of the maintenance process for pressure vessels.
This section covers information on the frequency with which inspections should happen, what is
done during inspections, the types of testing that can be used in inspections, and ends with a
checklist of what is generally covered during a pressure vessel inspection. Most pressure vessel
regulations provide specific requirements for the frequency of inspections. As a general rule of
thumb, pressure vessels should be inspected at least once every five years. An inspection should
also be conducted once the vessel is installed, prior to it being put into service.
Pressure vessel inspections can refer to an inspection of the vessel’s condition externally,
internally, or both.
In these inspections, inspectors may:

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  Collect visual data regarding the condition of the vessel, including the condition of
insulation, welds, joints, or structural connections
 Collect thickness data to determine whether the vessel has changed due to use
 Conduct a stress analysis to determine whether the vessel is still OK for use
 Inspect the vessel’s pressure release valves to make sure they functioning properly
 Conduct a hydrostatic pressure test.
TYPES OF PRESSURE VESSEL TESTING
There are five common types of tests inspectors perform during pressure vessel inspections:
1. VISUAL TESTING
Visual testing is the most common type of non-destructive testing (NDT) an inspector might
perform. The goal of a visual inspection is to visually review both the interior and exterior of the
vessel to look for any cracks or flaws (see the checklist just below for more details). Learn more
about visual inspections.
2. ULTRASONIC TESTING
Ultrasonic testing uses sound waves to measure the thickness of a material’s surface in order to
detect any defects that may have arisen. This kind of testing is volumetric, meaning it can detect
flaws inside the vessel as well as on its surface. Learn more about ultrasonic testing.
3. RADIOGRAPHIC TESTING
Radiographic testing uses radiography to detect defects near the surface or on the surface of a
vessel. This testing method is also volumetric. Learn more about radiographic testing.
4. MAGNETIC PARTICLE TESTING
Magnetic particle testing uses magnetic current run through the pressure vessel to identify
deformations or defects on the surface of the vessel, which will interrupt the flow of the magnetic
current and appear as a “flux leakage field.” Learn more about magnetic particle testing.
5. DYE PENETRANT TESTING
Dye or liquid penetrant testing uses liquid (i.e., the penetrant) sprayed onto the vessel to identify
defects or flaws on its surface. A fluorescent chemical can be added to the penetrant to make
flaws visible under U.V. light. Learn more about dye penetrant testing.
A pressure vessel inspection checklist is a document used to guide pressure vessel inspections.
The pressure vessel inspection checklist contains relevant information about pressure vessels,
such as pressure ratings, pressure relief valves, and other components. It also includes
instructions on how to carry out the pressure vessel inspection and any safety precautions that
must be taken during the inspection.
Not all pressure vessel inspection checklists are the same. In addition, some pressure vessel
inspection checklists may vary depending on the pressure vessel or pressure system being
inspected. However, pressure vessel inspection checklists, in general, should include the
following:

External Inspection
The external inspection covers the outer parts of pressure vessels. This includes the following
items:
 [ ] Leakage
 [ ] Coverings
 [ ] Corrosions
 [ ] Vessel mountings
 [ ] Potential cracks or other external damages

Internal Inspection
The internal inspection involves inspecting pressure vessels from the inside. This includes:
 [ ] Pressure rating

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  [ ] Interior surfaces
 [ ] Bolts and seals
 [ ] Pressure relief valves
 [ ] Tubing and connections
 [ ] Opening
 [ ] Special closures
 [ ] Corrosions, cracks, and other internal damages.

Pressure Test
Pressure tests are used to measure the pressure inside pressure vessels. This includes:
 [ ] Pressure pressure readings
 [ ] Leakage checks
 [ ] Valve pressure tests

Piping Systems
This section of your checklist covers pressure vessels connected to piping systems. This includes:
 [ ] Piping pressure rating
 [ ] Connections
 [ ] Ventilation system pressure tests
 [ ] Provision of support and expansion
 [ ] Cracking, Leakage, corrosion, and other potential damages

Documentation
Documentation is a crucial part of pressure vessel inspection. This includes:
 [ ] Test results
 [ ] Inspection dates and times
 [ ] Documentation of pressure vessel performance

Having a pressure vessel inspection checklist can help ensure that pressure vessel inspections are
done properly and efficiently. In addition, with a pressure vessel inspection checklist, you can
proactively catch pressure vessel issues before they become serious problems. Ultimately,
pressure vessel inspection checklists can help you maintain pressure vessels and systems for
optimal safety and performance.
Creating a pressure vessel inspection checklist is not as difficult as you think. You just need to
know the key information that you need to include in your pressure vessel inspection checklist.
You should gather key information about pressure vessels, such as pressure ratings and pressure
relief valves. You should also seek guidance from pressure vessel inspection specialists or an
expert.
Next, you must decide which sections to include in your pressure vessel inspection checklist.
Some pressure vessels may require additional sections; others may require fewer sections.
Finally, you should create your pressure vessel inspection checklist and ensure it complies with
pressure vessel safety regulations. Once your pressure vessel inspection checklist is complete,
you can use it to inspect pressure vessels properly and efficiently.

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 2019/2018
Answer the following questions (any ten):
a) What is Pool Fire? (Repeated)
b) What do you mean by flammability limits? (Repeated)
c) What is STEL? (Repeated)
d) Define hazard. Name two hazardous chemicals. (Repeated)
e) What do you mean by TNT equivalent? (Repeated)
f) What is Adiabatic Flame temperature? (Repeated)
g) What do you mean by off-site emergency plan? (Repeated)
h) State some of the toxic effects of lead? (Repeated)
i) What is hydro testing? (Repeated)
j) What is the function of a sprinkler? (Repeated)
k) What do you mean by deflagration? (Repeated)
l) State some of the probable causes of pipeline failure. (Repeated)
m) What is Fire Ball? (Repeated)

2015
1. Answer the following questions (any ten):
a) What is Jet Fire? Give an example.
Ans :- A jet fire occurs when a flammable liquid or gas is ignited after its release from a
pressurized, punctured vessel or pipe. The pressure of release generates a long flame, which is
stable under most conditions. A flash flame may take the form
of jet flame on reaching the spill point. The duration of the jet fire is determined by the release
rate and the capacity of the source. Flame length increases directly with flow rate. Typically a
pressurized release of 8Kg/s would have a length of 35m. The cross winds also the flame length.
b) What are the "Guide Words" of HAZOP study?
Ans :-
NO OR NOT -Complete negation of the design intent
MORE -Quantitative increase
LESS- Quantitative decrease
AS WELL AS -Qualitative modification/increase
PART OF -Qualitative modification/decrease
REVERSE- Logical opposite of the design intent
OTHER THAN -Complete substitution
c) What is STEL? :- (Repeated)
d) What do you mean by "On-site Emergency"?
Ans:- An On-site Emergency is one, which is having negligible effects outside the factory premises
and primarily be controlled

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by internal facilities and resources available. Some help may be required from external agencies
or local authorities. Once the on-site emergency plan is finalized, works management should
ensure that it is made known to all workers and to external emergency services where applicable.
Works managements should arrange for the emergency plan to be regularly tested, including the
following elements: i) Communications systems which would be in operation during an
accident: ii) Evacuation procedures
The plan should include the following information. However necessary addition or alteration may
be made according to the specific type of hazards and their control measures Purpose:
 To identify assess, foresee and work out the possible hazards To work out a plan with
detailed instruction to cope with the emergent situation arising out of the hazard
 The policy should be declared to cope up with the emergency which may arise due to own
operations, adjacent operation and out side forces at any time of day and night
 Declare the responsibility to protect all persons and property of the factory against
accident and emergencies
 Adequate emergency control procedure are to be laid down
 All personnel are to be well trained and informed for mitigating the emergencies
 System to inform the surrounding should be effective
 Provision for alarms and emergency equipment must be made Site plan: The site plan
should show the areas of various hazards such as fire explosion, toxic release and location
of assembly points, fire station, emergency control room, alternate emergency control
room, first aid or ambulance room, main gate, emergency gate, normal wind direction, out
side fire stations, police station, hospitals, communication facilities and other services-
mention their distances also.

e) What do you mean by "Vapor Balancing" during loading/unloading of petroleum

products?
Ans :- "Vapor Balancing" means a closed system that allows the transfer or balancing of vapors,
displaced during the loading or unloading of petroleum products, from the tank being loaded to
the tank being unloaded.
f) What are LEL and UEL of a fuel?
Ans :- Lower explosive limit (LEL): The lowest concentration (percentage) of a gas or a vapor in
air capable of producing a flash of fire in presence of an ignition source (arc, flame, heat). The
term is considered by many safety professionals to be the
same as the lower flammable limit (LFL). At a concentration in air lower than the LEL, gas
mixtures are "too lean" to burn.
Upper explosive limit (UEL): Highest concentration (percentage) of a gas or a vapor in air
capable of producing a flash of fire in presence of an ignition source (arc, flame, heat).
Concentrations higher than UFL or UEL are "too rich" to burn.
g) What do you mean by Auto Ignition Temperature?
Ans :- The autoignition temperature or kindling point of a substance is the lowest temperature at
which it spontaneously ignites in normal atmosphere without an external source of ignition, such
as a flame or spark. This temperature is required to supply the activation energy needed for
combustion.
h) What is Adiabatic Flame Temperature? :- (Repeated)
i) What do you mean by Deflagration? :- (Repeated)
j) Give examples of BLEVE, VCE and Detonation.
Ans :- BLEVE: Examples of BLEVE are LPG (propane), Vinyl Chloride and propylene
VCE – Vapour Cloud Explosion are two type CVCE (Confined Vapour Cloud Explosion), examples
are Isobutane, Hydro Carbon, Propane & Cyclo-hexane and UVCE (Un confined Vapour Cloud
Explosion. Examples of e.g. vessel, pipe, building, pit etc.)

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Detonation: - Examples of Detonation are Acetylene, Ether and Hydrogen.
Detonation (from Latin detonare, meaning "to expend thunder") involves
a supersonic exothermic front accelerating through a medium that eventually drives a shock front
propagating directly in front of it. Detonations occur in both conventional solid and liquid
explosives, as well as in reactive gases. The velocity of detonation in solid and liquid explosives is
much higher than that in gaseous ones, which allows the wave system to be observed with
greater detail (higher resolution).

k) What do you understand by TNT equivalent? :- (Repeated)

l) What is the duty of operator of a facility containing hazardous chemicals as per MS&IHC
Rules,1989 as amended?
Ans :- The duty of operator of a facility containing hazardous chemicals as per MS & IHC Rules
1989 as amended:
1) The operator of a facility shall be responsible for proper collection,reception,treatment,
storage and disposal of hazardous wastage listed in schedule in 1,2 and 3
2) The operator or any other person acting on his behalf who intends to get his hazardous waste
treated by the operator of a facility under sub rule (1) shall give, to the operator of a facility, such
information as may be specified by the (state pollution control board or committee)
3) It shall be responsibility of the operator of a facility, to take all steps to ensure that the wastage
listed in schedule 1,2 and 3 are properly handled, and disposed of without any adverse effects to
the environment
2015 (oct)/2010
Answer the following questions (any ten): -
a) What is Pool Fire?
Ans :- A pool fire is a turbulent diffusion fire burning above a horizontal pool of vaporising
hydrocarbon fuel where the fuel has zero or low initial momentum. Fires in the open will be well
ventilated (fuel-controlled), but fires within enclosures may become under-ventilated
(ventilation-controlled)
b) How is Pool Fire different from Jet Fire?
Ans :- A pool fire is a turbulent diffusion fire burning above a horizontal pool of vaporizing
hydrocarbon fuel where the fuel has zero or low initial momentum. A jet or spray fire is a
turbulent diffusion flame resulting from the combustion of a fuel continuously released with
some significant momentum in a particular direction or directions.
c) What is BLEVE?
Ans :- The abbreviation of ‘Boiling liquid expanding vapor explosion’ an explosion phenomenon
caused by the rapid phase change of liquid (vaporization). A liquid substance stored in a
pressurized vessel is in a vapor liquid equilibrium condition. When it is heated to a temperature
that is higher than the boiling point of the substance at atmospheric pressure, pressure also rises
in the container. When the container is damaged under this condition and the gas escapes, the
pressure in the container drops to atmospheric pressure in an instant. The equilibrium state in
the container is broken and an explosion phenomenon results from the bumping of the liquid that
is rapidly changed into the gas phase. This is BLEVE. The large vapour that resulted became an
enormous fire ball. It is a combination of fire and explosion with an intense radiant heat emission
within a very short interval of time. Example- The Feyzindisaster
d) What is HAZOP?
Ans :- A hazard and operability study (HAZOP) is a structured and systematic examination of a
planned or existing process or operation in order to identify and evaluate problems that may
represent risks to personnel or equipment, or prevent efficient operation; it is carried out by a
suitably experienced multidisciplinary team (HAZOP team) during a set of
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meetings. The HAZOP technique is qualitative, and aims to stimulate the imagination of
participants to identify potential hazards and operability problems; structure and completeness
are given by using guideword prompts. The HAZOP technique was initially developed to analyze
chemical process systems, but has later been extended to other types of systems and also to
complex operations such as nuclear power plant operation and to use software to record the
deviation and consequence.
e) What do you mean by TLV?
Ans :- The threshold limit value (TLV) of a chemical substance is a level to which it is believed a
worker can be exposed day after day for a working lifetime without adverse health effects.
Strictly speaking, TLV is a reserved term of the American Conference of Governmental Industrial
Hygienists (ACGIH). However, it is sometimes loosely used to refer to other similar concepts used
in occupational health and toxicology. TLVs, along with biological exposure indices (BEIs), are
published annually by the ACGIH.
f) What do you mean by off-site emergency plan?
Ans :- The off-site emergency plan coincides with the purpose of on-site emergency plan of a
factory and will go through the on-site emergency plan of all factories in the jurisdiction and will
suggest the missing aspect if any. The on-site
emergency plan will be in advance while making the off-site /disaster management plan. Thus,
on-site and off-site plan together will be single cooperative package for the common purpose of
fighting the emergency.
Purpose-
• To save lives and injured persons
• To prevent or reduce property losses
• To provide quick resumption of normal situation
• To plan for safe evacuation, shelter in assembly point and transportation
• To contain, limit localize and minimize loss, damage to environment, equipment or injury to
person
• To provide for continuous monitoring system.
• To carry out mock drills to ensure efficiency of the plan.
• To arrange for distribution of copies of printed plan to all concerned.
Lay out plan of the area of jurisdiction-
The plan should include location of all industries and all necessary points should be shown for
guidance.
Risk assessment-
While carrying out the risk assessment, the past experience of accident should be considered.
Other unforeseen criteria i.e. explosion, missile attack, war, riots should be considered for the
preparation of dispersion models of toxic release. Map showing dispersion criteria, area and
population should be laid down.
g) Briefly describe Domino Effect.
Ans :- A domino effect or chain reaction is the cumulative effect produced when one event sets off
a chain of similar events.[1] The term is best known as a mechanical effect, and is used as an
analogy to a falling row of dominoes. It typically refers to a linked sequence of events where the
time between successive events is relatively small. It can be
used literally (an observed series of actual collisions) or metaphorically (causal linkages within
systems such as global finance or politics). It is the chronological order of five dominos are
i- Lack of control – Management,
ii- Basic causes – origins,
iii- Immediate causes – symptoms,
iv- Accident – contact,
v- Injury/damage – loss.
h) What is MAH installation?

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Ans :- As defined u/r 2(g) of the Chemical Accidents (EPPR) Rules, 1996, it means isolated
storage and industrial activity [u/r 2(c)] at a site handling (including transport through carrier or
pipeline) of hazardous chemicals [defined u/r 2(b)] equal to or in excess of the threshold
quantities specified in Schedules 2 and 3.
It is also similarly defined u/r 2 (ja) of the Manufacture, Storage and Impact of Hazardous
Chemicals Rules, 1989. Different rules (Safety Provisions) are applicable to such factories,
installations or sites depending on "Threshold quantity" of hazardous chemicals listed in
Schedule 1, 2, and 3, or processes mentioned in Schedule 4.
i) What is the difference between deflagration and detonation?
Ans :- A deflagration is characterized by a subsonic flame propagation velocity, typically far
below 100 m/s, and relatively modest overpressures, say below 0.5 bar. The main mechanism of
combustion propagation is of a flame front that moves forward through the gas mixture - in
technical terms the reaction zone (chemical combustion) progresses through the medium by
processes of diffusion of heat and mass. In its most benign form, a deflagration may simply be a
flash fire. In contrast, a detonation is characterized by supersonic flame propagation velocities,
perhaps up to 2000 m/s, and substantial overpressures, up to 20 bars. The main mechanism of
combustion propagation is of a powerful pressure wave that compresses the unburnt gas ahead
of the wave to a temperature above the auto-ignition temperature. In technical terms, the
reaction zone (chemical combustion) is a self-driven shock wave where the reaction zone and the
shock are coincident, and the chemical reaction is initiated by the compressive heating caused by
the shock wave.
Detonation(from Latin detonare, meaning "to expend thunder") involves a supersonic
exothermic front accelerating through a medium that eventually drives a shock front propagating
directly in front of it. Detonations occur in both conventional solid and liquid explosives, as well
as in reactive gases. The velocity of detonation in solid and liquid explosives is much higher than
that in gaseous ones, which allows the wave system to be observed with greater detail (higher
resolution).
j) Give names of a few toxic chemicals.
Ans :- A toxic chemical as any substance which may be harmful to the environment or hazardous
to your health if inhaled, ingested or absorbed through the skin. Examples of few toxic Chemicals
are i) Acetaldehyde ii)Acetone iii) Acrolein iv) Bromine v) Chlorine vi) Cyanogens vii) Isopropyl
alcohol v)L-limonene
k) What is the objective of a Safety Value?
Ans :- The objective of Safety valueare
i) Think about what is safety, what is its need, where it is required, what are its type and
application etc.
ii) Protect and serve the mankind, to search, suggest and apply
a) the safe ways of behavior (action)
b) the safe working conditions
c) the safe environment for the safety, health and welfare of all people.
l) What is DOW Index?
Ans :- Dow’s Fire and Explosion Index (F&EI) is the most widely used hazard index. American
Institute of Chemical Engineers (AIChE) describes F&EI as the quantitative measurements
which are based on historical data, energy potential of the materials under evaluation, and the
extent to which loss prevention practices are currently applied. F&EI
is valuable as a guide to decide whether it is necessary for process designers to consider other
less hazardous materials and/or other process routes. F&EI helps engineers to be aware of the
hazards in each process unit while making important decisions in reducing the severity and/or
the probability of the potential incident. F&EI relates process hazards to process information in
terms of “penalties” and “credit factors”. It should be borne in mind that not every penalty is
applicable to the process under evaluation so that careful judgment should be made and

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discussed with the expert if necessary. F&EI is based on the “worst case” which means only the
most hazardous material are evaluated at a time in a specific operational state. For example,
when a process unit has hazards posed by flammable liquids and dusts, F&EI must be determined
based on both flammable liquids and dusts. Then, the higher F&EI and business interruption
must be the one that is reported to the management as the worst case.
m) Define hazardous chemicals with two examples.
Ans :- Hazardous chemical defines any chemical that is a health hazard or a physical hazard. A
chemical hazard is a type of occupational hazard caused by exposure to chemicals in the
workplace. Exposure to chemicals in the workplace can cause acute or long-term detrimental
health effects. There are many types of hazardous chemicals, including neurotoxins, immune
agents, dermatologic agents, carcinogens, reproductive toxins, systemic toxins, asthmagens,
pneumoconiotic agents, and sensitizers.[1] These hazards can cause physical and/or health risks.
Depending on chemical, the hazards involved may be varied, thus it is important to know and
apply the PPE especially during the lab.Two examples of hazardous chemicals are silica dust and
carbon monoxide.
2014/2011
Answer the following questions:
a) Flash fire:- A flash fire is defined by CGSB 155.20-2000 and NFPA 2113 as: “A rapidly moving
flame front which can be a combustion explosion. Flash fire may occur in an environment where
fuel and air become mixed in adequate concentrations to combust flash fire has a heat flux of
approximately 84 kW/m2 for relatively short periods of time, typically less than 3 seconds.”
b) BLEVE :- (Repeated)
c) Fire ball :- The resulting size and shape of the fire ball following the BLEVE failure of a vessel
was dependent on the amount of fuel in the vessel and the mode of failure. The resulting external
radiation field and hence received dosage are dependent on fuel mass, wind speed and direction.
The duration of the fireball was seen to be dependent on the mas of fuel involved. Surface
emissive power is highest for the smallest release, because a smaller mass is superheated such
that, it flashes to vapour most rapidly, producing a highly radiative flame. The resultant fireballs
gave their maximum power output before the fireballs reached their maximum volume and close
to the lift off time
d) Pyrophoric iron :- Pyrophoric Iron (FeS) is a form of iron sulphide that combusts on
exposure to oxygen; in this case with air. It is formed by reaction of hydrogen sulphide with
carbon steel. The iron in the steel reacts with hydrogen sulphide to create an iron crust scale on
the metal surface.
Pyrophoric deposits frequently from in storage tanks and processing units when iron oxide (rust)
reacts with sulfur in the product being handled:
Fe2O3 + 3H2S’ 2FeS + 3H2O + S
Upon exposure to air, the iron sulfide will react with oxygen:
4FeS + 3O2’ 2Fe2O3 + 4S + Heat
The reaction between iron sulfide and oxygen is exothermic and can provide enough heat to
ignite any combustible material in or around the deposit.
e) DOW index :- (Repeated)
f) Sprinkler :- A Water sprinkler system is an active fire protection method, consisting of a water
supply system, providing adequate pressure and flowrate to a water distribution piping system,
onto which fire sprinklers are connected. Sprinkler systems are intended to either control the fire
or to suppress the fire. Control mode sprinklers are intended to control the heat release rate of
the fire to prevent building structure collapse, and pre-wet the surrounding combustibles to
prevent fire spread. Suppression mode sprinklers are intended to result in a severe sudden

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reduction of the heat release rate of the fire, followed quickly by complete extinguishment, prior
to manual intervention.
Water sprinklers are six types i) Wet Pipe ii) Dry pipe iii) Pre-action iv) Deluge v) Combined dry
pipe vi) pre-action& sprinkler
g) Toxic gases :- These are gases that are harmful to humans when inhaled or ingested in various
quantities. This includes gases such as ammonia, chlorine, Sulphur, and many other. The
definition of a toxic gas is:“ A compressed gas or vapor that has a median lethal concentration (LC
50) in air of 200 parts per million (ppm) by volume, or 2 milligrams per liter of mist, fume, or
dust, when administered by continuous inhalation for one hour (or less if death occurs within one
hour) to albino rats weighing between 200 and 300 grams each.”
h) Explosion :- Explosion is the result of rapid combustible with a sudden, violent change of
pressure involving the liberation and expansion of a large volume of gas. Thus, release of energy
in a rapid and uncontrolled manner gives rise to explosion. The released energy may appear as
heat, light, sound or mechanical shock. Its effect depends on the rate at which the
energy is released.
Three types of energy can be released: physical, chemical or nuclear.
Bursting of tyre, vessel, pipe etc. due to overpressure or brittle fracture and flushing of
superheated liquid (thermal energy) are examples of physical energy.
Chemical energy is released due to chemical reaction. If may be uniform as in case of a vessel, or
it may be propagating as in case of a long pipe. Exothermic or runway reaction, decomposition
and polymerisation are also examples of chemical explosion.
Nuclear energy release can cause nuclear explosion.
Explosion are two types i.e. deflagration and detonation
i) Limits of in flammability :- Flammability limits or explosive limits: Mixtures of dispersed
combustible materials (such as gaseous or vaporized fuels, and some dusts) and air will burn only
if the fuel concentration lies within well defined lower and upper bounds determined
experimentally, referred toes flammability limits or explosive limits. Combustion can
range in violence from deflagration, through detonation, to explosion. Limits vary with
temperature and pressure, but are normally expressed in terms of volume percentage at 25 °C
and atmospheric pressure. These limits are relevant both to producing and optimizing explosion
or combustion, as in an engine, or to preventing it, as in uncontrolled explosions of build-ups of
combustible gas or dust. Attaining the best combustible or explosive mixture of a fuel and air.
(explosion range in between LEL & UEL)
j) Threshold limits :- The threshold limit value (TLV) of a chemical substance is a level to which
it is believed a worker can be exposed day after day for a working lifetime without adverse health
effects. Strictly speaking, TLV is a reserved term of the American Conference of Governmental
Industrial Hygienists (ACGIH). However, it is sometimes loosely used to refer to other similar
concepts used in occupational health and toxicology. TLVs, along with biological exposure indices
(BEIs), are published annually by the ACGIH.
2012
Answer the following questions (any ten): -
a) What is Fire Ball :- (Repeated)
b) What do you mean by flammability limits? :- (Repeated)
c) What is STEL? :- A short-term exposure limit (STEL) is the acceptable average exposure over a
short period of time, usually 15 minutes as long as the Time weighted average is not exceeded.
STEL is a term used in occupational health, industrial hygiene and toxicology. The STEL may be a
legal limit in the United States for exposure of an employee to a chemical substance. The
Occupational Safety and Health Administration (U.S. OSHA) has set OSHA-STELs for 1,3
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Butadiene, benzene and ethylene oxide. For chemicals, STEL assessments are usually done for 15
minutes and expressed in parts per million (ppm), or sometimes in milligrams per cubic meter
(mg/m3). The American Conference of Governmental Industrial Hygienists publishes a more
extensive list of STELs as threshold limit values (TLV-STEL)
d) Define hazard Name Two hazardous chemicals. :- (Repeated)
e) What do you mean by TNT equivalent? :- TNT equivalent is a method of quantifying the
energy released in explosions. The "ton of TNT" is a unit of energy equal to 4.184gigajoules (1
gigacalorie), which is approximately the amount of energy released in the detonation of a ton of
TNT. The "megaton of TNT" is a unit of energy equal to 4.184 petajoules.
f) What is Adiabatic Flame temperature?:- Adiabatic flame temperature is the temperature
that results from a complete combustion process that occurs without any work, heat transfer or
changes in kinetic or potential energy. It is two type constant volume adiabatic flame
temperature &constant pressure adiabatic flame temperature.
g) What do you mean by Offsite Emergency plan? :- (Repeated)
h) State some of the toxic effects of Lead? :- If levels of lead in blood are high enough --
generally above 70 μg/dL – clinical signs and symptoms of lead poisoning and possibly acute
encephalopathy may be present. Early symptoms of lead poisoning include abdominal pain and
constipation. Acute lead encephalopathy is characterized by irritability, lethargy, coma, seizures,
and in some cases, death.
i) What is Hydrotesting? :- A hydrostatic test is a way in which pressure vessels such as
pipelines, plumbing, gas cylinders, boilers and fuel tanks can be tested for strength and leaks. The
test involves filling the vessel or pipe system with a liquid, usually water, which may be dyed to
aid in visual leak detection, and pressurization of the vessel to the specified test pressure.
Pressure tightness can be tested by shutting off the supply valve and observing whether there is a
pressure loss. The location of a leak can be visually identified more easily if the water contains a
colorant. Strength is usually tested by measuring permanent deformation of the container.
Hydrostatic testing is the most common method employed for testing pipes and pressure vessels.
Using this test helps maintain safety standards and durability of a vessel over time. Newly
manufactured pieces are initially qualified using the hydrostatic test. They are then re-qualified at
regular intervals using the proof pressure test which is also called the modified hydrostatic test.
Testing of pressure vessels for transport and storage of gases is very important because such
containers can explode if they fail under pressure.
j) What is the function of a sprinkler? :- (Repeated)
k) What do you mean by deflagration? :- (Repeated)
l) State some of the probable causes of pipeline failure.:- Causes of failure of pipelines are: a)
Inadequate allowance for expansion/contraction b) Inadequate supports/poor support c) Metal
thinning due to corrosion/erosion. d) Poorly made joints. e) Wrong choice of material of
construction or not conforming as prescribed; f) Inadequate inspection/use of old pipes. g) Water
hammering h) Dead end failure

2019/2018
1). What are the safety facilities that must be provided for designing a fixed roof storage
tank in a refinery? Give the classification of petroleum products that can be stored in fixed
roof and floating roof tanks according to their flash points.

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Ans :- The following points should be taken care for the safety of the tanks containing
A. Flammable chemicals:
i) storage tanks should preferably installed in open air on ground or below ground level.
ii) They should be of good material, sound construction proper factor of safety.
iii) Tanks should be surrounded by a concrete dyke wall so as to contain entire hold up of the
tank in case of major or tank failure.
iv) Flammable chemicals spill from tank should be connected to treatment system and spill can
never mix with storm water channels.
v) Flammable chemicals spill from tank should be connected to treatment system and spill can
never mix with storm water channels.
vi) All equipments needed for pumping loading and un loading including electrical installation
should be flame proof /explosion proof type.
vii) Adequate fire fighting equipment-fixed or mobile should be provided in the storage area.
viii) For highly inflammable liquid storage tank, provision for foam pouring system in to the tank
should be made.
ix) Storage tank and all other equipments should be bonded and suitably earthed to maintain
electrical continuity and arrest accumulation of static charges.
x) Tanks should be provided with level gauges, temperature and pressure indicators/recorders.
xi) Tanks should be provided with vent/relieve vent opening fitted with flame arrester.
xii) Warning signs as per MSDS should be posted near the tank.
B.TOXIC CHEMICALS:
i) Pressurised tanks must have two independent relief valves fitted at the top-each having
capacity to relieve the pressure exceeding the operating pressure.
ii) Temperature control arrangement should be in operation all time for cryogenic fluids.
iii) The tank should be insulated if it works below ambient temperature.
iv) Atmospheric storage tanks have two peripheral walls and insulating materials are kept in
between.
v) Wind direction indicator should be fixed at the top of the tank.
vi) The relief vents should terminate to vent stack or flare.
vii) Construction of tank should be made as per design to withstand the severe operating
condition with adequate factor of safety.
viii) The vessel should have name plate details indicating the full storing capacity, safe filling
capacity, name of the manufacturer and date of testing.
ix) The storage area must be well ventilated and illuminated at all times.
x) Arrangement for emergency power supply to refrigeration system and other vital equipments
is to be ensured.
xi) In order to avoid dependence on promptness of person to control emergency, mechanisation
through modern control system(DCS-PLC) should be incorporated.
xii) Emergency planning has to be made in advance to mitigate any emergency within least
possible time and incurring minimum loss.
2) . Natural gas (assumed to be pure methane, mol. Wt. 16g/mol) flows along a pipe of
inner diameter 0.5m at a speed of 3m/s. The pressure of the gas in the pipe is 1 bar and the

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temperature 300K. Calculate - (a) the mass flow rate. (b) the molar flow rate, (c) the
volumetric flow rate, (d) the Reynold's number.(2015 Feb)
Ans :-

Molecular Wt. of methane = 16 gm/mol

U = (velocity) = 3 m/sec
Pressure of gas (P) = 1 bar = 1 atmosphere
= 1 kg/cm2
Temp. = 300 k
Sol-C- Volume flow rate = velocity c Area
= 3 m/sec x π/4 d2= 3 x π/4 x (0.5)= 0.588 m3/Sec
Sol-a-22.4 liter of methane at 273 k & 1 atm = 16 gms.
Therefore, 1 litter will weight = 16/22.4gm
( At 00C & 1 atmosphere Vol. is 22.4 litter)
P1V1 / T1 = P2 V2/T2
=(1 x 0.59)/300 =1 x V2
= V2 = 0.55 m3
=550 litter will weight = 16/22.4 x 550 gm
= 392.86 gm
Hence, Mass flow rate = 392.86 gm/Sec.
Sol-b-
Molar flow rate = 392.86/16 = 24.55 moles/Sec
Sol-d-
Re = D v ꝭ
µ
µ⇾ Viscosity
D ⇾ 1 meter V ⇾ m/sec
ꝭ ⇾ kg/m 3
ꝭ = m/volume = 392.86 gm/0.588 m3
= 0.392 kg/0.588 m3
= 0.67 kg/m3
1 poise = 100 centipoise = 1/10 pas. Second
= 1/10 kg/m.sec
D = 0.5 m.
∴ Re = (0.5 x 3 x 0.67)/ 1 x 10-5{ Viscosity of any gas is (1/10) x (10-4) = 10-5 }
= 1.005 x 105
3) . What are safety valves? Sketch the elements of a pressure safety valve. How high
temperature safety release is designed and constructed?
Ans :- Safety valve is a valve which has the function of increasing the safety of a thermal
hydraulics plant. An example of a safety valve could be a pressure safety valve (PSV), that is a

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pressure release valve (PRV) which automatically releases substance from a boiler, pressure
vessel, or other system, when the pressure or temperature exceeds present limits. Also,
pilot -operated relief valves could have the function of safety valve. Safety valves were first used
on steam boilers during the industrial Revolution. Early boilers operating without them were
prone to accidental explosion. Vacuum safety valves (or combined pressure/vacuum safety
valves) are used to prevent a tank from collapsing while it is being emptied, or when cold rinse
water is used after hot CIP (clean in place) or SIP (sterilization-in-place) procedures. When sizing
a vacuum safety valve, the calculation method is not defined in any norm, particularly in the hot
CIP/ cold water scenario, but manufacture have developed sizing simulations.
Temperature and pressure relief valves, also called T&P valves, are emergency safety limit
devices that will prevent or relief over heated water and pressure. Without a relief valve during
an unsafe condition, the pressure inside the tank would rise to the point the tank may rupture or
explode. This would cause potential damage to both people and property. Rheum water heaters
are pressure tested to 300 pounds per square inch (PSI) and have a working pressure of
150(PSI). The TNP valve is designed to open when the pressure inside the tank exceeds 150PSI,
allowing pressure to vent safely. The T&P valve will also open if the water temperature reaches to
100F. The valve will remain open allowing cold water into the tank until the unsafe condition is
over.

Components of a Relief Valve.

4) . A plant contained two identical spherical containers for propane storage at ordinary
temperatures (25°C) each designed to hold 750 tonnes. The diameter of each sphere is
15m. If such a sphere contains its nominal payload of 750 tonne, calculate (a) the vapor
pressure, (b) the volume of the voltage space, (c) the weight of propane in the vapor phase
and the proportion of propane in the vapor phase. Data required: latent heat of
vaporization of propane 18.5 KJ/mol, density of liquid propane at 25°C - 493 kg/m³,
normal boiling point of propane -42°C (231K). .(2015 Feb)
Ans :-

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 2017/2013
5. What is a run-away reaction? Give some examples of a few run-away reactions? What
are precautions must be taken for design and operation of such reactors?
Ans :- (Repeated)
6. What is a process piping and instrumentation diagram? Draw such an instrumentation
diagram for inbuilt safety of a high temperature vessel without using any controller?
Ans :- Piping and Instrumentation Diagrams (P&IDs) use specific symbols to show the
connectivity of equipment, sensors, and valves in a control system. These symbols can represent
actuators, sensors, and controllers and may be apparent in most, if not all, system diagrams.
P&IDs provide more detail than a process flow diagram with the exception of the parameters, i.e.
temperature, pressure, and flow values. "Process equipment, valves, instruments and pipe lines
are tagged with unique identification codes, set up according to their size, material fluid contents,
method of connection (screwed, flanged, etc.) and the status (Valves - Normally Closed, Normally
Open)."[1] These two diagrams can be used to connect the parameters with the control system to
develop a complete working process. The standard notation, varying from letters to figures, is
important for engineers to understand because it a common language used for discussing plants
in the industrial world.
P&IDs can be created by hand or computer. Common programs, for both PC and Mac, that create
P&IDs include Microsoft Visio (PC) and OmniGraffle (Mac). As with other P&IDs, these programs
do not show the actual size and position of the equipment, sensors and valves, but rather provide
a relative positions. These programs are beneficial to produce clean and neat P&IDs that can be
stored and viewed electronically. See below for P&ID templates for these programs.
This section covers four main types of nomenclature. The first section describes the use of lines to
describe process connectivity. The second section describes letters used to identify control
devices in a process. The third section describes actuators, which are devices that directly control
the process. The final section describes the sensors/transmitters that measure parameters in a
system.
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A piping and instrumentation diagram displays the piping components (for example
equipment, valves, reducers and so on) of an actual physical process flow and is often used in the
engineering projects, such as setting up steam boilers, heat exchangers, electric boilers and more.
To read a piping and instrumentation diagram, simply break down the overall diagram into
smaller parts and then trace from a single equipment and follow the pipeline. The latter type
shows a picture of the separate steps of a process in sequential order.
Main purpose of using piping and instrumentation diagrams are:
 To better understand the design conditions of an engineering project;
 To operate, maintain and modify the process system efficiently;
 To conveniently layout out and demonstrate the physical sequence of systems with the
focus on the control and shutdown schemes, safety and regulatory requirements, and the
basic start-up and operational details.
Advantages
 A well-prepared Piping and Instrumentation Diagram enables the personnel to evaluate
the construction process almost accurately
 Helps in forming a strong foundation for control programming
 Serves as a generic symbolic language that can be used by the designers from all regions
across the globe to communicate with each other and share their ideas related to the
industrial automation
 Helps in preparing and implementing safety control systems
Disadvantages
 P&ID charts are not completely reliable as they do not contain accurate details
 It is challenging to draw Piping and Instrumentation Diagrams independently, and require
a Process Flow Diagram (PFD) as a referral illustration
 Cannot be reused in multiple projects, and a separate Piping and Instrumentation Diagram
must be tailored for each company
 Correct symbols and icons must be used while drawing a Piping and Instrumentation
Diagram failing to which, the engineers may end up preparing a faulty piece of equipment
Piping and instrumentation diagrams have been used in many fields such as metallurgical sector,
air conditioning industry, power generator sectors and so on. The key usages of such diagrams
are:
 For designing a manufacturing process for a physical plant with complex chemical or
mechanical steps. This is especially important for a safety check.
 For training new workers and contractors before they start work in the plant.
 To derive project capital cost estimate and develop project contract specification, for
example, the guidelines and standards for facility operations.

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7. What are the safety norms followed in transporting chemicals through pipelines? Briefly
point out the start-up and shut-down procedures to be adopted for reaction vessels?
Discuss about the standard schedule of maintenance of reaction vessels?
Ans :- Pipelines are required to carry a variety of materials such as water, steam, air, oil, gas (inert
or toxic, vapour or compressed), brine, solvent and other liquid and gaseous chemicals. From
storage tanks to process vessels, from process vessels to product tanks and from there to filling
(loading) points, pipelines are required. They may be above ground, underground or as per
requirement. Some 20 to 30% costing is estimated in pipelines and their fittings like flanges,
valves, gauges, nipples, glands, bends, elbows, plugs, reducers, joints, couplings, ferules, vents,
drains etc. Pipework may be of cast iron, mild steel, stainless steel, lead, copper, plastic i.e. PVC,
PP, HDPE, rubber, canvas, glass, FRP, glasslined, rubber lined, teflon coated, asbestos cement,
RCC, stone, ceramic etc. '
1. Inspection by an experienced engineer for assessment of work.
2. written work permit specifying precautions to be observed and procedure to be followed.
3. The section of the pipeline shall be isolated, drained and purged with inert gas or steam or kept
filled with water or treatment approved by the CC.
4. Work of cutting or welding to be carried out by an experienced person in accordance with the
permit
5. Only mechanical cutters shall be used for cutting the pipeline or any connection thereof unless
it has been purged with an inert gas.
6. Separation of pipeline or valve fitted to it only after providing electrical bond between the
parts, to be separated and the bond shall not be broken till the parts have been rejoined.
7. Reuse of the repaired section only after hydrotest as stated in rule 93.
Safety Aspects of Pipe work :
Generally probability of leakage from pipelines is proportional to the length of pipelines, number
of joints, valves, vents, bleeds, drains etc. and complexity such as number of pump connections,
recycle streams, hours of working, etc. Therefore it is advisable to
1. Minimise pipe length, branches and joints, and flanges on vacuum lines.
2. Provide welding joints for highly flammable or toxic chemical, good gaskets and gland packing,
flange guard to deflect leak downward, flexibility to allow thermal expansion, bellows subjected
to axial movement, drains and traps at visible places, removable plugs on sample points,
adequate pipe supports, walkways, platforms or working place, proper slopping for draining,
overhead clearance for vehicle movement (about 6 m), ergonomic design for valves to be
operated and gauges to be seen, earthing and bonding to remove static charge due to flow,
overflow return from measuring vessel to a storage tanks, painting with colour coding (IS:2379)
and cathodic protection where required.
More pipework in dyke is not desirable, particularly with hazardous chemical, as it may be
trapped in fire in the dyke. Similarly pipelines of flammable or toxic chemical should not be laid in
tunnel, as its leak may spread from one area to another. Electric cables or hot lines and flammable
gas or liquid lines should not run side by side. Solvent line should not be laid below the corrosive
line. Seam joints of rubber lined pipes should be kept upward.
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. Flushing arrangement should
be provided for easy start up and maintenance. Pipe alleys should not run over the walking alleys,
normal layout should be near the walls or in sides. To allow for thermal expansion special joints
or loops should be provided.
Emergency control valves should be easily accessible. By-pass valves should be within easy
reach. Autocontrol valve should have bypass or manual valve which may be required in the event
of failure of autocontrol valve. Particularly at the outlet of bulk storage of hazardous chemicals,
manual and remotely controlled auto isolation valve both should be provided as near as possible
to the outlet.

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Pressure relief device, liquid seal, manual vent valve etc. should be provided to depressurise the
system where necessary.
Many different types of valve exist. It is essential to choose the type best suited for the particular
operation it has to perform. For instance, if ball valves are to be fitted in a high pressure position,
they should be trunnion mounted. Where positive segregation of products is required, say at a
multi-product manifold, it is essential to provide block and bleed valves for continuous
monitoring of valve seats and seals. For positive isolation some form of soft .seat with a wedge
gate action is desirable.
Pumps must be designed not only to suit the immediate pipeline requirements, but should take
into account future developments. Thus, it may be necessary to stipulate a pump casing pressure
much higher than the pump can generate, if series or boosting pumping is envisaged. Care should
be taken to ensure that additional or larger impellers can be fitted as the system demand grows.
The maximum operating pressure for the pump mechanical seals should match the pump
capabilities. It may be necessary to provide product filtration to protect the minimum clearance
of the pump moving parts, particularly on modern high efficiency pumps.
Flexible pipes, joints and hoses should be safe, sound and properly tested. Bolted clips are
preferred to jubilee clips. Proper supports or hangers are necessary.
Glass piping, equipment or gauge needs external protection to protect against external impact or
internal bursting and flying fragments coming out.
Layout drawings of piping and fittings should be maintained and corrected when any changes are
incorporated.
Use of plastic piping is increasing. When it is used for hazardous gas like hydrogen, LPG,
chlorine etc., utmost care is required to ensure safe joint. Normally metal compression fittings
(rings and nuts) are used. Softer ring is preferred over hard compression ring. Nut should not be
loosened. It should be frequently checked for leakage. When any leakage is noticed, first the
supply cylinder valve should be closed instead of operating any electric switch or spark
generating device.
Semi-conductive material for hoses preferred over non-conductive or good conductive material
to avoid static electricity. The conductance should be between in 10-4 to 10-8 mho.
Failure of packing in valves, stems or flange gaskets, opening the wrong valve or failure to
depressurise the system before opening the joint and un insulated steam or hot lines can cause
accidents.
Remedial measures are splash guard, replacement of gasket, tagging and work permit procedure,
colour coding and proper training and supervision.
In above ground pipe work which remains isolated during normal operations, thermal relief
system should be provided to protect against increasing ambient temperature.
8. What are the safety valves? Sketch the elements of a pressure safety valve? How high
temperature safety release is designed and constructed?
Ans :- (Repeated)

2015 (Feb)
9. In a vessel used to store acrylonitrile out of doors where the temperature is 5°C, there is
a space above the liquid surface of volume 50 lit (0.05 m³). This contains air and an
equilibrium quantity of acrylonitrile, total pressure 1 bar. The contents of the space are
accidentally discharged into the surrounding atmosphere, and it is estimated that
occupants of the nearest buildings will experience, in the short term, a conc. of
acrylonitrile equal to that in 50 lit space diluted, because of dispersion, by a factor of 10³.
What level of acrylonitrile in ppm, will the occupants of the building area be exposed to?
The heat of vaporization of acrylonitrile is 31 KJ/mol.
ADIS/2022-23/RAKESH KUMAR GUPTA/ROLL NO: -30 Page 27 of 60
Ans :-

10. Water, for subsequent use in process temperature control, is initially at 20°C and is to
be cooled to 7°C by means of a refrigerator which uses refrigerant R-12
(dichlorodifluoromethane). 150kg per minute of water so cooled are required. Neglecting
the temperature step between refrigerant and water, determine the pressures of
refrigerant in the compressor and in the evaporator. Determine also the circulation rate of
the refrigerant necessary. [Use steam table for saturated pressures at 20°C and 7°C,
specific entropies.
Ans :- (Do Yourself)

2015 (oct)
11. Elaborate the mathematical evaluation of diameter, duration and temperature of a
fireball based on given values of calorific value, molecular weight and Stephan Boltzmann
constant.
Ans :-

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12. What are the safety facilities those must be provided for designing a fixed roof storage
tank in a refinery? Explain also the classification of petroleum products which can be
stored in fixed roof and floating roof ranks according to their flash points.
Ans :- The following points should be taken care for the safety of the tanks containing
A. Flammable chemicals:
i) storage tanks should preferably installed in open air on ground or below ground level.
ii) They should be of good material, sound construction proper factor of safety.
iii) Tanks should be surrounded by a concrete dyke wall so as to contain entire hold up of the
tank in case of major or tank failure.
iv) Flammable chemicals spill from tank should be connected to treatment system and spill can
never mix with storm water channels.
v) Flammable chemicals spill from tank should be connected to treatment system and spill can
never mix with storm water channels.
vi) All equipments needed for pumping loading and un loading including electrical installation
should be flame proof /explosion proof type.
vii) Adequate fire fighting equipment-fixed or mobile should be provided in the storage area.
vili) For highly inflammable liquid storage tank, provision for foam pouring system in to the tank
should be made.
ix) Storage tank and all other equipments should be bonded and suitably earthed to maintain
electrical continuity and arrest accumulation of static charges.
x) Tanks should be provided with level gauges, temperature and pressure indicators/recorders.
xi) Tanks should be provided with vent/relieve vent opening fitted with flame arrester.
xii) Warning signs as per MSDS should be posted near the tank.
B. TOXIC CHEMICALS:
i) Pressurised tanks must have two independent relief valves fitted at the top-each having
capacity to relieve the pressure exceeding the operating pressure.
ii) Temperature control arrangement should be in operation all time for cryogenic fluids.
iii) The tank should be insulated if it works below ambient temperature.
iv) Atmospheric storage tanks have two peripheral walls and insulating materials are kept in
between.
v) Wind direction indicator should be fixed at the top of the tank.
vi) The relief vents should terminate to vent stack or flare.
vii) Construction of tank should be made as per design to withstand the severe operating
condition with adequate factor of safety.
viii) The vessel should have name plate details indicating the full storing capacity, safe filling
capacity, name of the manufacturer and date of testing.
ix) The storage area must be well ventilated and illuminated at all times.
x) Arrangement for emergency power supply to refrigeration system and other vital equipments
is to be ensured.
xi) In order to avoid dependence on promptness of person to control emergency, mechanisation
through modern control system(DCS-PLC) should be incorporated.
xii) Emergency planning has to be made in advance to mitigate any emergency within least
possible time and incurring minimum loss.

13. What is a run-away reaction? Give some examples of a few run-away reactions. What
are precautions must be taken for design and operation of such reactors?
Ans :- (Repeated)
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14. What are the safety valves? Sketch the elements of a pressure safety valve. How high
temperature safety release is constructed?
Ans :- (Repeated)
15. What is a process piping and instrumentation diagram? Draw such an instrumentation
diagram for inbuilt safety of a high temperature vessel without using any controller.
Ans :- (Repeated)

2014/2011
16. Elaborate the mathematical evaluation of diameter, duration and temperature of a
fireball based on given values of calorific value, molecular weight and Stephan Boltzmann
constant. (Repeated)
17. What are the safety facilities those must be provided for designing a fixed roof storage
tank in a refinery? Explain also the classification of petroleum products which can be
stored in fixed roof and floating roof ranks according to their flash points. (Repeated)
18. What is a run-away reaction? Give some examples of a few run-away reactions. What
are precautions must be taken for design and operation of such reactors?
Ans :- (Repeated)
19. What are the safety valves? Sketch the elements of a pressure safety valve. How high
temperature safety release is designed and constructed?
Ans :- (Repeated)

20. What is a process piping and instrumentation diagram? Draw such an

instrumentation diagram for inbuilt safety of a high temperature vessel without using
any controller. (Repeated)

2013
21) Name the different classes under UN classification of chemicals Give an example of
each.
Ans :- The hazardous chemicals/dangerous goods are divided by United Nation Committee of
Experts on the Transport of dangerous goods into the following classes:
 CLASS 1 : Explosive
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.
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.
Division 4 – Substances and articles which present no significant hazard.
Division 5 – Very insensitive substances which have a mass explosion hazard.
CLASS 2 : Gases compressed, liquefied, dissolved under pressure or deeply refrigerated.
CLASS 3 : inflammable liquids.
CLASS 4 : Inflammable solids, substances liable to spontaneous combustion substances which on
contact with water emit inflammable gases.

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Division 4.1 – Inflammable solids.
Division 4.2 – Substances liable to spontaneous combustion.
Division 4.3 – Substances which on contact with water, emit inflammable gases.
CLASS 5 : Oxidising substances, organic peroxides.
Division 5.1 – Oxidising substances.
Division 5.2 – Organic peroxides.
CLASS 6 : Poisonous (toxic) and Infectious substances.
Division 6.1 Poisonous (toxic) substances.
Division 6.2 Infectious substances.
CLASS 7 : Radioactive substance.
CLASS 8 : Corrosives.
CLASS 9 : Miscellaneous dangerous substance.
See IS:1446 for classification of dangerous goods.
Arrangement for loading and unloading of the liquid have to be well designed. It is preferred to
load toxic and flammable material from the bottom. It is preferable to provide a discharge pump
on the tank.
Drums, crates and cylinders are also transported by trucks. The important thing to see is that the
chemical is securely packed so that spillage do not occur on the road and the toxic vapours are
not released.
The cylinders or drums should be securely lashed so that they do not fall off the truck and cause
danger. The driver and the attendant should be fully conversant wiyh the nature of the material
and the hazards involved and trained to handle the situation.
22) Give a brief note on 'Emergency Information Panel"
Ans :- Emergency information Penal (R. 134) :
Such panel (marked on goods carriage i.e. vehicle shall contain -
1. The correct technical name of the hazardous goods in letters bigger than 50 mm size.
2. Class label of more than 260 mm2 size.
3. Telephone number of emergency services to I contacted in case of fire or any accident with
letters
and numbers of more than 50 mm size an also the name and telephone number of consignor or
other person to receive advice c emergency measures.
4. A sticker on vehicle showing goods being carried on in that trip.
See fig. 28.1 for dimensions of "Emergency Information Panel" and fig. 28.2 for its placement on
goods carriage.

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 EMERGENCY INFORMATION PANELS

Driver to be instructed (R. 135) :

The owner of goods carriage shall ensure the satisfaction of the consignor that the driver has
received adequate instructions and training to understand -
1. Nature of the goods.
2. Nature of the risks there from.
3. Precautions while driving or parking.
4. Action to be taken in case of emergency.
Report of Accident (R. 136) :
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.
ADIS/2022-23/RAKESH KUMAR GUPTA/ROLL NO: -30 Page 32 of 60
23) What is a Material Safety Data Sheet? (Repeated)
24) What information is available in a data sheet for a toxic chemical?
Ans :- 1. Chemical Identity:
1. Name of the Chemical
2. Formula
3. Synonyms
4. Trade name
5. Chemical Classification
6. Regulated identification
7. Shipping Name, Codes/Label
8. CAS No.
9. UN No.
10. ADR No.
11. Hazchem (EAC) No.
12. Hazardous Waste ID No.
13. 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. Melting/Freezing point
6. Vapour pressure
7. Solubility in water
8. Scrubbing/Neutralising/Inactivating media
9. pH
10. Others
3. Fire & Explosion Hazard Data :
1. Flash point
2. Autoignition Temperature
3. Flammable limits : LEL/.UEL
4. TDG Flammability
5. Explosion Sensitivity to Impact
6. Explosion Sensitivity to static electricity
7. Explosive material
8. Flammable material
9. Combustible and flammable Liquid
10. Pyrophoric material
11. Hazardous Combustion products
12. Hazardous Polymerisation
13. Corrosive material
14. Organic Peroxide
15. Oxidiser
16. Others
4. Reactivity Data:
1. Chemical stability
2. Incompatibility (Materials to avoid)
3. Reactivity
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4. Hazardous reaction products
5. Health Hazard Data :
1. TLV (ACGIH)
2. STEL/SET
3. LC50 or LD50
4. Odour threshold
5. Carcmogen ? Poison ? Liberates poisonous fume?
6. Routes of entry
7. Body parts that may be affected
8. Effects of exposure and symptoms
9. Emergency and first aid treatment
10. Engineering controls necessary for safe handling.
11. NFPA Hazard signals
12. Special Health hazards.
6. Preventive Measures:
1. Ventilation required and type
2. Personal protective equipment required and type
3. Handling and storage precautions
7. Emergency and First-aid Measure :
1. Steps to be taken in case material is released or spilled.
2. Waste disposal method for solid, liquid and gaseous waste.
3. Fire, extinguishing media, special procedures and Unusual hazards.
4. Exposure - First-aid measures. Antidotes, Dosages.
8. Additional Information / References
9. Manufacturer / Supplier's Data :
1. Name of Firm
2. Mailing address
3. Telephone/Telex/Fax Nos.
4. Telegraphic address
5. Contact person in emergency
6. Local bodies involved
7. Standard packing
8. Tremcard Details / Ref.
9. Other
25. What statutory requirements are to be fulfilled during transporting Hazardous Cargo
by all modes?
Ans :- Hazardous goods can be defined as materials or items with hazardous properties which if
not properly controlled, may present a potential hazard to human and animal health and safety,
the environment and infrastructure.. Hazardous goods must be classified, packaged, marked,
labelled and packed as per the regulations set out by the IMDG Code by the International
Maritime Organisation and also needs to be handled with utmost care and consideration of its
dangerous nature..
The transportation of hazardous goods both locally and internationally is subject to various
regulations depending on the origin and destination country.. The entities undertaking the
transportation of dangerous goods must strictly adhere to these regulations..
For intermodal transport, these rules and regulations may be related to transport within a
political or economic union or trading zone etc.. Most of these regulations may be based on
the United Nations Recommendations on Transport of Dangerous Goods (the Orange book)..

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However, international rules like the ADR and national rules like the CFR49 may differ from the
United Nations Recommendations on the Transport of Dangerous Goods..
The carriage of dangerous goods by sea is day by day increasing. About 4000 million tonnes
cargo enters world seaborne trade every year, of which about 100 million tonnes are dangerous
goods in packaged form. More than 1 lac types of hazardous chemicals are transported by sea.
They include solid, liquid and gases in bulk. While cutting oil-tanks and pipelines on ships at
Alang shipyard (Bhavnagar) many fatal accidents have taken place. Thus these are the end
problems even after transportation by sea.
International maritime Organisation (IMO), International Convention for the Safety Of Life At
Sea, 1974 (SOLAS 74) and International Convention for the Prevention of Pollution from Ships,
1973 (MARPOL 73) have developed guidelines and codes for carriage of dangerous goods in
packaged form by sea.
IMO has formulated International Maritime Dangerous Goods (IMDG) Code and 'Emergency
Procedures for Ships carrying dangerous goods (EmS)'.
SOLAS has formulated 'Code of safe Practice for the Shipment of Bulk Cargoes (BC Code)' for
transportation of dangerous solid goods in bulk.
Medical First Aid Guide (MFAG) for use in accidents involving dangerous goods, is available in
IMO/WHO/ILO publication. IMO/ILO guidelines for packing cargo in Freight Containers or
Vehicles and IMO recommendations on safe use of pesticides in Ships are also available.
SOLAS have classified dangerous goods in 9 classes [see UN Classification stated in foregoing
para].
Main information required are proper shipping name and UN No., chemical name, formula,
properties and observations, classification, packing, labelling, stowage and segregation, angle of
repose, MFAG table number and special emergency procedure and action to be taken.
Training courses for ship's officers and crew are also recommended.
26. What do you understand from the term 'Risk'? Name a few techniques for assessment
of risk in chemical industry. Explain in brief any of the risk assessment techniques?
Ans:- Risk is the probability of an outcome having a negative effect on people, systems or assets.
Risk is typically depicted as being a function of the combined effects of hazards, the assets or
people exposed to hazard and the vulnerability of those exposed elements.
1.Make a list (inventory)
Walk around your workplace, check your purchase orders and make a list of all the chemicals you
bring in and those generated by work activities or waste (welding fume, dust, residues).
2. Identify chemical hazards
The most important sources of information on the hazards of the chemicals brought into your
workplace are the label and safety data sheet (SDS). All chemical containers should be supplied
with a label which clearly identifies the chemical and its hazards. Where a chemical is hazardous,
the label should contain a signal word (danger or warning) and may include an associated
pictogram and a hazard statement giving more detailed information on the hazard (e.g. causes
serious eye irritation, causes skin irritation). It should also contain precautionary statements
giving advice on safety precautions to be taken (e.g. keep out of reach of children, wear protective
gloves / protective clothing / eye protection / face protection). Additional precautionary
information may be provided in the safety data sheet. The safety data sheet is a document that
should be provided by the supplier with all hazardous chemicals. The safety data sheet is a key
tool for risk assessment as it includes detailed hazard information, advice on safe handling, use
and storage, and the emergency measures to be followed in case of an accident.
3. Assess exposure
Once you have identified your chemical hazards you then need to assess what the potential
exposure is to your employees. This involves looking at each chemical which you have identified
as hazardous and considering the following questions:

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  How is the chemical used (e.g. sprayed, poured) and how often is the chemical used?
 How will the user be exposed? (e.g. breathing it in, contact with skin?)
 How much is used /generated ?
 How long is each user exposed to the chemical? (e.g. full shift or a few minutes?)
 Who uses the chemical? (e.g. how many people?)
 Are any vulnerable groups potentially exposed? For example, identify if reprotoxins are in
use.
 Is the chemical mixed with other chemicals or exposed to high temperatures or pressure?
 Can non-users be exposed? (e.g. people working nearby, visitors, cleaning or maintenance
staff?)
4. Control your chemical risks
Once you have assessed the risk associated with your chemicals, control measures must be put in
place in order to keep your employees, your workplace, and the environment safe.
You should first consider if you can eliminate the hazard by changing the process or removing the
hazardous chemical.
If you cannot eliminate the chemical(s), can you substitute the hazardous chemical with another,
non-hazardous or less hazardous chemical? For example, you could replace isocyanate based
paints with water based paints or you could use a less hazardous form of the same chemical (e.g.
using a pellet rather than a powder form of the chemical could have a significant effect on
reducing inhalable dust levels).
Where the above options are not possible, exposure to hazardous chemicals should be minimised
and additional control measures must be put in place to remove or reduce the risks to employees:

 Engineering controls e.g. local exhaust ventilation (LEV), on tool extraction, isolation /
containment hoods or booths
 Review of current work practices or procedures to reduce the frequency and length of
exposure
 Training for employees on the chemicals currently used in the workplace, what the
chemical hazards are and the potential risks to their health, and how to handle chemicals
safely
 Hygiene arrangements e.g. separate meal and wash facilities, designated smoking areas or
a no smoking policy
 Specific Storage arrangements so that chemicals are stored correctly, safely and securely.
(Information on storage is available in section 7 of the SDS)
 Personal protective equipment (PPE), e.g. eye protection, gloves, masks and respiratory
masks (RPE). As these are the last line of defence, they should not be used without first
considering the other controls above. Information on the correct PPE and RPE is provided
in section 6 of the SDS, but contact the supplier if unclear (Specify in your risk assessment
the exact glove type, filter type etc.)
 A good level of housekeeping
 Correct disposal of waste
 Emergency procedures in case of an accident, incident or spillage, e.g. eyewashes,
showers, spill kits
5. Record and review
Write down your findings (this can be part of a work instructions) and discuss them with your
employees. Consultation with your employees is necessary at every step and especially when
implementing the findings of your chemicals risk assessment.
You may need to draw up an action plan, detailing who is responsible, for what action and when
will it be carried out.
As no workplace remains the same, review your risk assessment at least once per year, and
update if necessary. When changes such as new employees, machinery, equipment or materials
occur in the workplace it is necessary to review the risk assessment. Change in work patterns
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such as overtime or shift work, the needs of pregnant/nursing employees and those with special
needs must also be included.

27) What is the need of permit in a chemical plant?

Ans :- Site Location Permits – These include the Environmental Impact Reports (EIRs), the
various planning and zoning public review procedures, and the evaluations on the impacts to the
area. The effort at this level usually requires a well thought out compliance strategy to meet the
various detailed regulatory program elements that will be triggered by this site location effort.
These generalized state or federal agency permits require involvement with the local political
infrastructure.
Agency Permits – The major agency permits usually include:
Employee Protection Agencies (OSHA, and state equivalents) – These agencies usually do not
have permits per se, but they have many regulatory requirements that must be put in place by
practice and policy for the project. For example: OSHA promulgates the regulations for the
Hazardous Communications Programs (Workers Right to Know), Hot Work Permits, Lock Out Tag
Out, and Confined Space Entry Programs.
OSHA Process Safety Management (PSM) – Any flammable that will be stored in excess of its
PSM planning threshold limit then triggers the full compliance with the federal Process Safety
Management program. These are good practices even if not subject to formal compliance, but
consideration must be given to the amount of time and effort it will require to insure compliance.
Methanol on site in storage in excess of 10000 lbs (1500 gallons) will trigger this regulatory
requirement.
Environmental Protection Agencies – Agencies such as the EPA, the state EPA equivalent, and
the state Department of Toxic Substance Control (DTSC) typically have a myriad of requirements
that are administered through the local building permit process. The establishment of good
relationships with these agencies in the early phase of a project is critical to reducing schedule
delays down the line. This is specifically evident as submitted information works through various
building departments’ compliance processes.
Wastewater Agencies – The primary focus is compliance with the National Pollutant Discharge
Elimination System (NPDES). In many cases an industrial facility does not directly pull an NPDES
permit, but is subject to the rules and regulations as the wastewater agency into which the
industrial site discharges will be subject to the NPDES regulation and permitting structure.
Solid Waste Permits – The interest here is to control the solid waste streams that exit the plant
site. These agencies usually were created by the continuing RCRA legislative suite of the federal
and state governments. In many cases where there is a high re-purposing of the generated waste
this is simply compliance with the characterization of the solid waste that can be transferred to
the local landfill. In many cases however, the interest is in the possible hazardous waste that can
be generated from the facility. In these instances, evaluation and compliance with the elements of
the Resource Conservation and Recovery Act (RCRA) gain importance. The hurdle here is
compliance with hazardous waste disposal permitting processes.
Water Districts – In many drought stricken areas or areas where the draw on local water sources
is significant, the plant must justify its use of the various proposed water sources.
Air Permitting Authorities – Compliance with the various EPA promulgated air emissions
standards are reviewed and regulated by type of hazard and characterization of effect on the
atmosphere present. Many local agencies have overlapping jurisdiction depending upon specific
location and the various restrictions or special district compliance requirements that may exist.
These include details regarding Hazardous Air Pollutants (HAPs), Volatile Organic Compounds
(VOCs), ozone depletion chemicals, toxic gases, and poisonous gases. A greenfield plant has a
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more difficult task in justifying its compliance with the various air programs versus a site that has
an established registered emission profile.
Other AHJs - There remain other associated state and federal agencies such as Fish and Wildlife
and the USDA that may require information submittals that support permits, compliance, or
understanding on a site or project specific basis. These will depend upon the information and
identified jurisdictions from the site location permit efforts in the first phase of the permit
pursuit.
Building Permits – The third grouping of permits come from the local building departments and
all the discipline and detailed local agencies funnel through the building permit issued by the
local AHJ. This is a summary permit that includes the local code enforcement officials’
requirements, the local fire prevention program requirements, and any other check point design
and discipline authority that might exist. Building permits always involves the submittals of
stamped and sealed: 1. Detailed civil and structural drawings 2. Detailed fire protection system
drawings 3. Detailed site drawings
28) What preparations have to be made before issuing a permit for entry in to confined
space?
Ans :- 1. 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%.
2. Air line or self contained breathing apparatus and safety belt are essential.
3. Sump pumps with flameproof electric or pneumatic motors and air extraction fans (spark
proof) and exhaust ducting to remove heavy vapours are necessary.
4. 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.
5. Latest safety and rescue systems should be used. Winch arrangement connected with the
worker's harness is useful to lower and pull out quickly. Handfree 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.
6. Bottom drain valve and other nozzles should be kept open to allow good ventilation and fresh
air in a vessel or tank
29) Prepare a format of permit to work in your industry.
Ans :- Name & Address of the Factory : _________________________________ Sr. No. : _____________
Name & Address of the Contractor : ________________________________ Date. : _____________

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30). The Bhopal gas disaster is considered to be the worst chemical disaster the world has
ever witnessed. Give your views to prevent recurrence of such disaster in future.
Ans :- (Do Yourself)

2012
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31. What are the safety, facilities that must be provided for designing a fixed roof storage
tank in a refinery? Give the classification of petroleum products that can be stored in fixed
roof and floating roof tanks according to their flash points. (Repeated)
32. Natural gas (assumed to be pure methane, mol. wt. 16g/mol) flows along a pipe of
inner diameter 0.5m at a speed of 3mvs. The pressure of the gas in the pipe is I bar and the
temperature 300K. Calculate - (a) the mass flow rate. (n) the molar flow rate, (e) the
volumetric flow rate, (d) the Reynold's number.
Ans :- (Repeated)
33. What are safety valve, Sketch the elements of a pressure safety valve. How high
temperature safety release is designed and constructed?
Ans :- (Repeated)

34. A plant contained two identical spherical containers for propane storage at ordinary
temperatures (25°C) each designed to hold 750 tonnes. The diameter of each sphere is
15m. If such a sphere contains its nominal payload of 750 tonne, calculate - (a) the vapor
pressure, (b) the volume of the voltage space, (c) the weight of propane in the vapor phase
and the proportion of propane in the vapor phase. Data required: latent heat of
vaporization of propane 18.5 KJ/mol, density of liquid propane at 250C=493 kg/m³,
normal boiling point of propane -42°C (231 K). (Repeated)

2010
35. A tank containing gasoline is surrounded by a circular dyke of diameter 10m. The
gasoline leaks and occupies the area bounded by the dyke. If there is ignition, calculate - (i)
the total radiative flux from the flame, (ii) the flame temperature, (iii) the radiative flux a
person standing 15m from the circumference will experience. Data given:
λ (fraction of total combustion heat transferred as radiation) = 0.4
Mass loss rate per unit pool area = 0.1kg/m2s
Density of air at ambient temperature = 1.17kg/m³
Calorific value of fuel = 45 MJ/kg
Ans :-

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36. A quantity of 60t propane stored as liquid under pressure escapes and forms a fireball.
Calculate the following (a) total heat released, (b) radiative heat released, (c) diameter of
the fireball, (d) duration of the fireball, (e) corresponding temperature under conditions
of radiative heat released. Data given:
Calorific value of propane = 50MJ/kg, Molar Mass = 0.044 kg/mol, a = 5.7×10 W/m²k4.
Ans :-

37) What do you mean by isolated storage of petroleum products?

Ans :- "isolated storage" means storage of a hazardous chemical, other than storage associated
with an installation on the same site specified in Schedule 4 where that storage involves atleast
the quantities of that chemical set out in Schedule 2;
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38) Define fixed roof and floating roof storage tanks. What are the different types of
floating roof storage tanks used in practice?
Ans :- Fixed roof storage tanks are pretty straight forward, and are generally considered the
minimum acceptable equipment for storing liquids. They are often the most practical and least
expensive option when storing products with a low vapor pressure (close to atmospheric
pressure). A typical fixed roof tank consists of a steel shell with a cone or dome shaped roof that
is permanently fixed to the tank shell. They are usually fully welded and designed to be both
liquid and vapor tight. Some designs allow installing a breather valve (pressure/vacuum valve)
that prevent the build-up of excessive pressure or vacuum
A 'Floating Roof', as its name implies, actually floats on the surface of the liquid in the tank. As
the liquid level changes the roof is designed to move up and down with the liquid level - i.e.
Filling, Emptying, Expansion and Contraction due to temperature changes. This type of tank roof
minimizes the vapor space between it and the liquid surface. Since there is no large vapor space
for the liquid to evaporate into, vapour losses are also minimized. In its simplest form, the
floating roof is merely a large, flat pan (or disc), slightly smaller in diameter than the tank shell.
It is fitted with a system of flexible 'shoes' to close the space between the edge of the roof and the
tank shell in order tominimisevapour loss. These tanks have a cylindrical steel shells equipped
with a roof that floats on the surface of the stored liquid; rising and falling along with the liquid
level.
External Floating Roof Tanks
This floating roof system is comprised of a deck, fittings, and a rim seal system.
Floating roof decks are constructed of welded steel plates and have three main types:
 Pan deck
 Pontoon deck
 Double deck
There is a annular space with seal gland between the floating roof and the tank wall, to separate
air when stored liquid float up or down on the roof, greatly reducing evaporation loss in the
storage process. Compared with fixed roof tank, using a floating roof tank to store oil product can
reduce evaporation loss to 80% approximately.
Internal Floating Roof Tanks
Internal floating roof tanks have a floating roof that moves up and down above the product level,
while at the same time include a fixed permanent roof above the tank’s shell. The internal floating
roof tank (IFRT) was developed in the mid-1950s to provide protection of the floating roof from
the elements, including lightning strikes to the floating roof. The tank vapor space located above
the floating roof and below the fixed-roof includes circulation vents to allow natural ventilation of
the vapor space reducing the accumulation of product vapors and possible formation of a
combustible mixture. Internal floating roof tanks provide the best option for controlling volatile
losses compared to fixed and external floating roof tanks.
39) Explain in details of use of fixed roof and floating roof storage tanks taking into
consideration of losses of products from the tanks.
Ans :- Product vapor control with floating roof tanks
In general, the floating roof covers the entire liquid surface except for a small perimeter rim
space. Under normal floating conditions, the roof floats essentially flat and is centered within the
tank shell. There should be no vapor space underneath a welded-steel floating roof. Under normal
conditions, the amount of product vapor that might become trapped beneath the floating roof
should be insignificant. However, if large quantities of flash vapor or other noncondensable
vapors become trapped, the floatation stability of the roof can be affected. These conditions
should be avoided if possible.
It is important to understand how a floating roof works and why details are so important in the
design of a floating-roof storage tank. The study of evaporative emissions from storage tanks and
possible methods to control or eliminate these emissions has been the focus of an extensive

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series of analytical studies, field, and laboratory testing programs sponsored by the American
Petroleum Institute.
40) What is the colour code in pipeline safety?
Ans :- IS-2379:Pipelines –Identification-Color-coding:-
Pipes and pipelines are fluid carrying media in the form of closed conduits .The system of colour
coding consists of a ground colour and colour bands superimposed on it .The ground colour
identifies the basic nature of the fluid carried and also distinguishes one fluid from another .The
different ground colours are:

SlNo. Fluid Ground Colour

1 water Sea grean
2 Fire water Fire red
3 Steam Aluminum
4 Mineral, vegetables oil, combustible liquid Light brown
5 Acids Dark violet
6 Alkaline Smoke-grey
7 Air Sky-blue
8 Gases Canary Yellow
9 Hydro carbons, organic compounds Dark admiralty grey
10 Other fumes black

41) In an autoclave operating at 80°C and initially containing 3t of VCM (Vinyl Chloride
Monomer) there is continuous passage of the unreacted monomer vapor, a: 80°C and its
saturated vapor pressure at that temperature, through a shell-and-tube heat exchanger.
The other fluid in the exchanger is water which enters at 25°C and exits at 60°C. The
autoclave conditions are maintained for 5 hrs and the polymerization goes to 90%
completion. Determine - (i) at what rate the VCM must recirculate through the heat
exchanger? (ii) at what rate the water must flow?

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Ans :-

42) There was an accident due to leakage of 60t Dimethyl Ether (DME) [Heat of
combustion = 31MJ/kg]. Calculate the blast energy assuming 5% of the total heat released
is the blast energy of DME.
Ans :- ( Do Yourself)

43) Describe the "Mock-Drill Procedure" that is necessary for an "On-site Emergency"
incident.
Ans :- The main objective of mock drill is to review emergency preparedness plan as well as
evaluate standard operation protocols in any places mainly on larger organizations, schools,
places where hazardous materials are used (chemicals, acids, LPG ) etc. which helps concerned
people to act in accordance with the emergency situation to safeguard life and property.
Example: During an outbreak of fire, the following steps should be followed
1. Try to get out from the burning building
2. Assist fire victims
3. To put down fire, utilize sand/wet cloth/clay
The ultimate goal of mock drill is to test and improve entire capability of an organization/
community by means of strengthening the relevant policies, plans and protocols. Preparing and
practicing on particular roles and responsibilities will give save number of lives, assets and
surroundings. Organization that create and constantly maintain feasible and practical exercises
mostly prepared to face such events.

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Mock drill exercises developed should be flexible and planned in accordance with the needs of
concerned organization. Mock drills conducted are not solutions for crisis but an efficient
approach towards implementing important priorities that would lead to innovative solutions.
Necessity of mock drill:
 To make people aware of hazards around them
 Ways to handle hazardous substances
 Inculcate preparedness among common public
 Know the value of resources belongs to various departments
 Examine SOPs and plans of industries
 Enhance resource capabilities

44) Describe the flammability region with a hypothetical sketch of fuel concentration
vs. temperature, clearly indicating the flash point, UEL, LEL and vapor pressure.
Ans :- (Do Yourself)

2019/2018
Write short notes on the following (any three):
a) Fukusima nuclear plant disaster :- The Fukushima Daiichi Nuclear Power Plant Fukushima
Daiichi GenshiryokuHatsudensho?) is a disabled BWR nuclear power plant located on a 3.5-
squarekilometre (860-acre) site[1] in the towns of Okuma and Futaba in the Futaba District
of Fukushima Prefecture, Japan. First commissioned in 1971, the plant consists of six boiling
water reactors (BWR). These light water reactors[2] drove electrical generators with a combined
power of 4.7 G We, making FukushimaDaiichi one of the 15 largest nuclear power stations in the
world. Fukushima was the first nuclear plant to be designed, constructed and run in conjunction
with General Electric, Boise, and Tokyo Electric Power Company (TEPCO). The plant
suffered major damage from the magnitude 9.0 earthquake and tsunami that hit Japan on March
11, 2011. The incident permanently damaged several reactors making them impossible to restart.
Due to the political climate, the remaining reactors will not be restarted. The disaster disabled the
reactor cooling systems, leading to releases of radioactivity and triggering a 30 km evacuation
zone surrounding the plant; the releases continue to this day. On April 20, 2011, the Japanese
authorities declared the 20 km evacuation zone
b) Lone Canal Tragedy :- Although the disposal of hazardous waste as a lone canal dated back to
the early 1940, the contamination of homes located near the sites did not become evident until
the mid-1960, when residents complain of fumes and minor explosion, doing the construction of
the LASALLE express-way, noxious fumes, corrosive waters and oily materials encountered,
according to states p[personal and local resident. When read avenue was installed some thirteen
years ago drums were exposed during the excavation works. Which allowed the release of
noxious fumes and oily liquids, causing several works stoppage. Noxious fumes and hazardous
liquid chemicals were detected in various storm sewers mostly to the west of the site, and the
outfall which collected the flow from both the 97 and 99 street sewer lines. In addition to this
problems, land subsidence in the grammar school playground occurred regularly, and the holes
are periodically filled with soil. School personnel reported to the County Health Department that
school children handled waste phosphorous and receive burns. In 1976, the New York
Department of Environment conservation NYDEC conducted its first investigation of suspected
leaching into nearby sewers and basement sumps. Based on these and subsequent testing the
following year, NYDEC hired an environment consulting firm, Calspan Corporation, to conduct its
own studies and later enlisted the help of the New York Department of Health NYDOH.

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c) Emergency preparedness :- "Emergency Preparedness is the discipline of dealing with and
avoiding both natural and manmade disasters." It involves mitigation, preparedness, response
and recovery in order to lessen the impact of disasters. Emergency management requires a
partnership among all levels of government (local, State, and Federal) and the private sector
(business and industry, voluntary organizations, and the public). Successful preparedness
requires detailed planning and cooperation among each sectors. Emergency preparedness ranges
from the Federal Emergency Management Agency (FEMA) developing an all inclusive plan to
mitigate natural disasters to the individual ensuring their car has plenty of fuel for a possible
evacuation. The following principles illustrate the emergency preparedness concept. Emergency
preparedness at all levels considers and takes into account all hazards, all phases, all
stakeholders and all impacts relevant to disasters. Anticipation of future disasters and
preventive and preparatory measures build disaster-resistant and disaster-resilient
communities. Sound risk management principles (hazard identification, risk analysis, and impact
analysis) are used in assigning priorities and resources. Unity of effort among all levels of
government and all elements of a community are integrated. Broad and sincere relationships
among individuals and organizations are incorporated to encourage trust, advocate a team
atmosphere, build consensus, and facilitate communication. Activities of all relevant stakeholders
are synchronized to achieve a common purpose. Creative and innovative approaches are used to
overcome disaster challenges. Emergency preparedness uses a science and knowledge-based
approach; based on education, training, experience, ethical practice, public stewardship and
continuous improvement. Management consists of four phases: Mitigation, Preparedness,
Response, and recovery.
d) HAZOP study:- A hazard and operability study (HAZOP) is a structured and systematic
examination of a planned or existing process or operation in order to identify and evaluate
problems that may represent risks to personnel or equipment, or prevent efficient operation; it is
carried out by a suitably experienced multidisciplinary team (HAZOP team) during a set of
meetings. The HAZOP technique is qualitative, and aims to stimulate the imagination of
participants to identify potential hazards and operability problems; structure and completeness
are given by using guideword prompts. The relevant international standard [1] callsfor team
members to display 'intuition and good judgement' and for the meetings to be held in 'a climate of
positive thinking and frank discussion'. The HAZOP technique was initially developed to analyse
chemical process systems, but has later been extended to other types of systems and also to
complex operations such as nuclear power plant operation and to use software to record the
deviation and consequence. HAZOP-type studies may also be carried out by considering
applicable guide words and identifying elements to which they are applicable[1] or by
considering the parameters associated with plant elements and systematically applying guide
words to them; although this last approach is not mentioned in the relevant standard, its
examples of output include a study (B3) recorded in this way.[1] The following table gives an
overview of commonly used guide word – parameter
2017/2013
Write short notes on the following (any three):
a) Fukusima nuclear plant disaster (Repeated)
b) Bhopal gas tragedy :- The Bhopal Gas Tragedy, 1984 was a catastrophe that had no parallel
in the world’s industrial history. In the early morning hours of December 3, 1984, a rolling wind
carried a poisonous gray cloud from the Union Carbide Plant in Bhopal, Madhya Pradesh (India).
Forty tons of toxic gas (Methy-Iso-Cyanate, MIC) was accidentally released from Union Carbide’s
Bhopal plant, which leaked and spread throughout the city. The result was a nightmare that still
has no end, residents awoke to clouds of suffocating gas and began running desperately through
the dark streets, victims arrived at hospitals; breathless and blind. The lungs, brain, eyes, muscles
ADIS/2022-23/RAKESH KUMAR GUPTA/ROLL NO: -30 Page 46 of 60
as well as gastro-intestinal, neurological, reproductive and immune systems of those who
survived were severely affected. When the sun rose the next morning, the magnitude of
devastation was clear. Dead bodies of humans and animals blocked the street, leaves turned black
and a smell of burning chili peppers lingered in the air. An estimated 10,000 or more people died.
About 500,000 more people suffered agonizing injuries with disastrous effects of the massive
poisoning. None can say if future generations will not be affected.
c) HAZOP study (Repeated)
d) Seveso disaster :- The Seveso disaster was a chemical accident on 10 July 1976, at the small
Italian town of Meda, 20 km from Milan in Lombardy. There was an explosion at a chemical
factory which released a lot of the toxic poison dioxin, TCDD, into the air.[1] The cloud of poison
gas covered an area 6 km long and 1 km wide. It was named after the municipality of Seveso.
It resulted in the highest known exposure to 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD) in
residential populations. There were many studies and new regulations after the accident. The
European Union directive covering the protection against such accidents is known as Seveso-II-
directive today. The company where the accident happened was called Icmesa. It was owned by
Givaudan, who is owned by Roche. Icmesa produced Trichlorophenol, which is used to produce
the disinfectant Hexachlorophene. The company was located in four communes; one of them
Seveso. None of the 20,000 people who lived in Seveso died, but the poison killed 3,000 farm
animals and pets. Another 70,000 animals had to be killed to stop the dioxin from getting into the
food chain. Thirty years after the accident, scientists reported that babies born in the area
affected by the dioxin were six times more likely to have thyroid problems. The affected children
are being studied to see if this has stopped them growing properly, or having problems with
intellectual development (IQ).
e) Minimata disease :- It is a neurological syndrome caused by severe mercury poisoning.
Symptoms include ataxia, numbness in the hands and feet, general muscle weakness, narrowing
of the field of vision, and damage to hearing and speech. In extreme cases, insanity, paralysis,
coma, and death follow within weeks of the onset of symptoms. A congenital form of the disease
can also affect foetuses in the womb. Minamata disease was first discovered in Minamata city in
Kumamoto prefecture, Japan, in 1956. It was caused by the release of methyl mercury in the
industrial wastewater from the Chisso Corporation's chemical factory, which continued from
1932 to 1968. This highly toxic chemical bio-accumulated in shellfish and fish in Minamata
Bay and the Shiranui Sea, which, when eaten by the local populace, resulted in mercury
poisoning. While cat, dog, pig, and human deaths continued for 36 years, the government and
company did little to prevent the pollution. The animal effects were severe enough in cats that
they came to be called "dancing cat fever."
f) Chemical spillage control procedures

2015(Feb)
. Write short notes on the following (any three):
a) Lone canal Tragedy (Repeated)
b) HAZOP study (Repeated)
c) MAH installation :- As per to MAHC Rules, 1997 “major accident” means an incident involving
loss of life inside or outside the site or 10 or more injuries inside and / or one or more injuries
outside or release of toxic chemical or explosion or fire or spillage of hazardous chemicals
resulting in ‘on-site’ or ‘off-site’ emergencies or damage to equipment leading to stoppage of
process or adverse effects to the environment and
“hazardous chemical” means,
- any chemical which satisfies any of the criteria laid down in Part I of Schedule 1 or

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is listed in Column 2 of Part II of this Schedule; or
any chemical listed in Column 2 of Schedule 2; or
any chemical listed in Column 2 of Schedule 3;
Major Accident Hazard Control Rules, 1997 framed to supplement the Rules already notified
under Chapter IV-a of the
Factories Act, 1948underd Rule shall apply to –
an industrial activity in which a hazardous chemical, which satisfies any of the criteria laid down
in Part I of Schedule 1 or
is listed in Column 2 of Part II of this Schedule is or may be involved; and
isolated storage in which there is involved a quantity of a hazardous chemical listed in Column 2
of Schedule 2 which is equal to or more than the threshold quantity specified in this Schedule for
that chemical in Column 3 thereof.
d) Off-site Emergency Planning. :- The offsite emergency plan coincides with the purpose of
onsite emergency plan of a factory and will go through the onsite emergency plan of all factories
in the jurisdiction and will suggest the missing aspect if any. The onsite emergency plan will be in
advance while making the offsite /disaster management plan. Thus, on site and off-site plan
together will be single cooperative package for the common purpose of fighting the emergency.
PURPOSE-
• To save lives and injured persons
• To prevent or reduce property losses
• To provide quick resumption of normal situation
• To plan for safe evacuation, shelter in assembly point and transportation
• To contain, limit localize and minimize loss, damage to environment, equipment or injury to
person
• To provide for continuous monitoring system.
• To carry out mock drills to ensure efficiency of the plan.
• To arrange for distribution of copies of printed plan to all concerned.
LAY OUT PLAN OF THE AREA OF JURISDICTION
The plan should include location of all industries and all necessary points should be shown for
guidance.
RISK ASSESSMENT
While carrying out the risk assessment, the past experience of accident should be considered.
Other unforeseen criteria i.e. explosion, missile attack, war, riots should be considered for the
preparation of dispersion models of toxic release. Map showing dispersion criteria, area and
population should be laid down.
2015 (oct)
Write short notes on the followings:
a) Fukusima nuclear plant disaster (Repeated)
b) MINIMATA disease (Repeated)
c) Bhopal gas tragedy (Repeated)
d) 'Stephen Court' fire in Kolkata :- This is a list of historic disastrous urban fires are the most
numerous due to loss of life and property, but also included are lists of fires in individual
structures, ships and other transportation, and mines. A few of the most of important wildfires
are included but this list is not the primary resources for the most severe wildfires, which is
summarized in the list of forest fires.
This is an incomplete list that may be able to satisfy standards for completeness. You can help by
expanding it with reliably sourced entries.

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e) Toxic effect of lead and its compounds :- If levels of lead in blood are high enough --
generally above 70 μg/dL – clinical signs and symptoms of lead poisoning and
possibly acute encephalopathy may be present. Early symptoms of lead poisoning include
abdominal pain and constipation. Acute lead encephalopathy is characterized by irritability,
lethargy, coma, seizures, and in some cases, death.
2014/2011
Write short notes on the followings:
a) Fukusima nuclear plant disaster(Repeated)
b) MINIMATA disease :- (Repeated)
c) Bhopal gas tragedy (Repeated)
d) ‘Stephen Court' fire in Kolkata (Repeated)
e) Toxic effect of lead and its compounds (Repeated)

2013
Write short notes on any two of the following
a) BLEVE (Repeated)
b) MSDS (Repeated)
c) Criteria for the plant to be under MAH unit
Ans :- As per to MAHC Rules, 1997 "major accident" means an incident involving loss of life inside
or outside the site or 10 or more injuries inside and / or one or more injuries outside or release
of toxic chemical or explosion or fire or spillage of hazardous chemicals resulting in 'on-site' or
'off-site' emergencies or damage to equipment leading to stoppage of process or adverse effects
to the environment and "hazardous chemical" means, -
any chemical which satisfies any of the criteria laid down in Part I of Schedule 1 or is listed in
Column 2 of Part II of this Schedule; or
any chemical listed in Column 2 of Schedule 2; or
any chemical listed in Column 2 of Schedule 3;
Major Accident Hazard Control Rules, 1997 framed to supplement the Rules already notified
under Chapter IV-a of the Factories Act, 1948underd Rule shall apply to -
an industrial activity in which a hazardous chemical, which satisfies any of the criteria laid down
in Part I of Schedule 1 or is listed in Column 2 of Part II of this Schedule is or may be involved; and
isolated storage in which there is involved a quantity of a hazardous chemical listed in Column 2
of Schedule 2 which is equal to or more than the threshold quantity specified in this Schedule for
that chemical in Column 3 thereof.

d) Colour coding of pipe lines. (Repeated)

e) Runaway reactions (Repeated)

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 2010
Write short notes on any three of the following:
a) Seveso disaster (Repeated)
b) Bhopal Gas tragedy (Repeated)
c) Flixborough disaster :- The Flixborough disaster was caused by an Unconfined Vapour Cloud
Explosion. At 16:53 on Saturday 1 June 1974, a 20 inch temporary bypass pipe (containing
cyclohexane at 150°C (302°F) and 1 MPa (10 bar)) ruptured, which may have been caused by a
fire on a nearby 8 inch pipe for nearly an hour. Within a minute, about 40 tonnes of the plant's
120 tonne store of cyclohexane leaked from the pipe and formed a vapour cloud 100–200 metres
(320–650 feet) in diameter. The cloud, on coming in contact with an ignition source (probably a
furnace at a nearby hydrogen production plant) exploded, completely destroying the plant.
Around 1,800 buildings within a mile radius of the site were damaged.
d) Emergency preparedness (Repeated)
e) Safety audit :- Audit is a systematic and, wherever possible, independent examination to
determine whether activities and related results conform to planned arrangements and whether
these arrangements are implemented effectively and are suitable to achieve the organization's
policy and objectives. (BS8800: 1996 Guide to Occupational health and safety management
systems)The health and safety management audit our members adopted is a structured process
of collecting independent information on the efficiency, effectiveness and reliability of the total
H&S management system and drawing up plans for corrective action. Auditing examines each
stage in the H&S management system by measuring compliance with the controls the
organization has developed, with the ultimate aim of assessing their effectiveness and their
validity for the future. (Successful H&S Management, HS(G)65)
Types of safety audit:Health and safety audits, Walk around audit, Health and safety
management audit, Project Health, Safety &Environment auditing, Process safety auditing,
Product safety audit, The Safety & Health Audit Recognition Programme.

2017/2013
1. Answer any thirty questions:
Expand the followings: -
i. MSDS :- Material Safety Data Sheet
ii. DMP :- Disaster Management Plan
iii. UNO :- United Nations Organization
iv. MSIHC :- Manufacture, Storage, and Import of Hazardous Chemicals
v. NIOSH :- National Institute for Occupational Safety and Health
vi. OISD :- Oil Industry Safety Directorate
vii. UCVE :- unconfined vapor cloud explosion
viii. BLEVE :- Boiling-Liquid-Expanding-Vapor Explosion
ix. HAZOP :- hazard and operability study
x. EIA :- Environmental Impact Assessment

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 2012
Write short notes on the followings (any three),
a) Fukusima nuclear plant disaster (Repeated)
b) Lone canal tragedy (Repeated)
c) Emergency preparedness (Repeated)
d) HAZOP study (Repeated)

2017/2013
State whether the following statements are True or False:
xi) Chemical accident cannot be classified. False
xii) In modem chemical industries plant safety inspection are exempted by Factories
Act. True
xiii) Release of toxic gas is not a chemical hazard. False
xiv) Highly inflammable chemicals for a flash point higher than 60°C but lower than 90°C. False
xv) Dilution of a toxic chemical reduces exposure. True
xvi) No standard & codes of practice are available for isolated storage. False
xvii) MSDS shall be accessible to all employees at all level. True
xviii) Colour coding of pipe lines is not mandatory for chemical process plant. False
xix) Minimum two safety valves are required for the storage tank handling toxic
substances. True
xx) All vessels meant for storage of compressed gasses shall be installed entirely above
ground. True
xxi) The system of colour coding consists of a ground colour and colour bands super
imposed on it. True
xxii) Work permit system is not essential for maintenance/repair of chemical plants.
False

2013
Write True or False against each statement:
i. Construction of a building storage/process vessels should be as per NFPA standard No. 86.
False
ii. Regular rehearsal of emergency preparedness is to be ensured and such exercises should
be done once in six months as per relevant rules. True
iii. Bhopal gas disaster was caused by an unconfined vapour cloud explosion in the year 1974.
False
iv. The 3500ppm of CO and 600ppm of 112S may be immediately fatal to life. True
v. Benzene poisoning is a notifiable disease U/S 89, 90 of Factories Act. True
vi. Chlorine cylinders should be stored up-right. True

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vii. Bulk storage tanks and vessels have to be approved and licenses under the static and
mobile pressure vessels(unfired) Rules. 1987. False
viii. The MSDS in respect of hazardous substances should be updated as and when necessary.
True
ix. A pressure vessel shall be thoroughly examined by a competent person internally once in
a period of six months. False (12 months)
x. As per rule no.377 of 1.R.B. every boiler shall be hydraulically tested in the presence of an
Inspector or Inspecting Officer. True

2017/2013
Fill in the blanks
xxiii) Section 41G of the Factories Act deals with hazardous process.
xxiv) First Schedule of the Factories Act is the LIST OF INDUSTRIES INVOLVING HAZARDOUS
PROCESSES
xxv) HAZOP study is suitable for identify and address potential hazards
xxvi) A dyke wall is required surrounding the be Concentrated acid storage tanks.

2017/2013
Match the pair:
xxvii) Chlorine. a) Poisons and Flammable
xxviii) L.P.G. b) Toxic
xxix) Methane- c) Flammable
xxx) Electrical Fire- d) Foam
xxxi) Jute Fire e) CO₂
xxxii) Chemical Fire. f) Water
ANS: - xxvii)-b, xxviii)-c, xxix-a, xxx)-e, xxxi)-f, xxxii-d

2013
Write any fifteen of the followings: -
i. in UN classification of chemicals corrosives belong to which class? Class VIII
ii. In how many classes chemicals are grouped as per UN classification? Nine Classes
iii. The Seveso disaster occurred in which year and on what date? July 10, 1976
iv. What is the full abbreviation of BLEVE? Boiling Liquid Expanding Vapour Explosion
v. What chemical was involved in Flixborough disaster? cyclohexane
vi. Should oxygen be introduced inside a confined space for oxygen deficient atmosphere?
Give hazards of excess oxygen. increased risk of fire and explosion
vii. What is the width of bands in colour coding? Minimum 25mm

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Note :- Colour bands are superimposed on the ground colour. Minimum width of colour band is
25 mn Width ratio of first band to second band should be 4:1 Size of lettering should be as under :
Outer Dia of Pipe Letter size
Covering (mm) (mm)
20 to 30 10
30 to 50 20
50 to 80 30
80 to 150 40 etc.
viii. What is the recommended colour code for firefighting equipment’s? Fire red.
ix. Who is authorized to issue work permit? Responsible person
x. On which day the Seveso disaster occurred? Saturday, Weekend
xi. Who are required to prepare the “onsite” and “offsite” emergency plans? Onsite-occupier
& Offsite-Concern Authority
xii. In which year the MAHC rules were enacted?
Note :- (1) These Rules may be called The Major Accident Hazard Control Rules, 1997
(2) They shall come into force on the date of their publication in the Official Gazette as per
the procedure laid down under the Factories Act, 1948.
(3) These Rules supplement the Rules already notified under Chapter IV-a of the Factories
Act, 1948
xiii. The MAHC rules supplement the rules framed under an act name is? Factories Act, 1948
xiv. Which toxic chemical is responsible for Seveso disaster? - 2,3,7,8-tetrachlorodibenzo-p-
dioxin (TCDD)
xv. Work permit has become mandatory under WB Factories Rules. Name relevant clause and
schedule the said rules?
Ans :- According to WB Factories Rule 1958, Schedule-XVIII , Chemical Work ,Part-II (General
Requirement)
20. Permit to work system. - The 'permit to work system' shall inter-alia include the observance
of the following precautions while carrying out any specified work to be subjected to the permit
to work system,
(a) all works subject to the permit to work system shall be carried out under the control and
direct supervision of a knowledgeable and responsible person;
(b) all parts of plant or machinery or equipment on which permit to work system is carried
out, shall remain isolated from the other parts throughout the period of permit to work and
the place of work including the parts of plant, machinery shall be rendered safe by cleaning,
purging, washing etc., as may be necessary;
(c) all work subject to the permit to work system shall have predetermined work procedures
which integrate safety with the work. Such procedures shall be reviewed whenever any
change occurs in material or equipment so that continued safety is ensured;
(d) it shall be ensured that workers who are assigned to carry out the permit to work system
are physically fit in all respects taking into consideration the demands and nature of the
work before allowing or requiring entry or work into the confined space. Such workers
shall be adequately informed about the work procedures as well as the precaution to be
observed while carrying out the permit to work system.
(e) adequate rescue arrangements wherever considered necessary, and adequate first aid
rescue and rescurrection arrangement available in good working condition near place of
work while carrying out the permit to work system, for use in emergency;
(f) appropriate personal protective equipment duly certified by Indian Standards Institute be
provided and used while carrying out 'permit to work system';

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 (g) after completion of work subject to the 'permit to work system' the person responsible for
control and supervision shall ensure to remove all the equipments and tolls and restore to
the original condition so as to prevent danger while carrying out regular process.
xvi. What is the normal validity of a permit? works. (Do Yourself)
xvii. What is the meaning of 'No' in HAZOP guide word?
Ans :- The complete negation of these intentions
xviii. What is the value of penalty for combustion reaction under GPH in compiling Dow index?
(Do Yourself)
xix. Write the famous law of probability to find the chance of accident(Do Yourself)
xx. Use of dispersion model is an essential criterion under which plan? (Do Yourself)

Examination –Internal Assessment

Paper Code-IS-203
Chemical Safety in Industry
Years- 2020-21

Total Marks -20 Time : 1 Hr

Note: Solve any Four Question

Q.1. Explain the importance of pipeline in chemical safety

Ans:- i) Pipelines are used extensively to transport liquids, gases and also solids by converting
them into a slurry, such as water, petroleum end natural gas.
ii) Pipelines are also used to transport liquidities coal.
iii) Pipelines are effective in connecting remote regions to supply networks and offers an
uninterrupted flow of goods.
The following paints to be taken into account:
i) The pipelines are ideally suited to transport the liquids and gases.
ii) Pipe lines can be load, thorough difficult tarring as well as water.
iii) It involves very low energy consumption
iv) The initial cost of laying pipelines is high but subsequent running costs are minimum
v) It rules out trans shipment losses as delays.
Pipeline may be above ground, underground or as per requirement, some 20 to 30% costing is
estimated and pipelines and their fittings like flange, valves, gauges, nipples, glands, lends,
allows, plugs, reducers, joint, couplings, vents, drains etc. pipe work may be of cast Iron, mild
steel, stainless steel, lead, copper, plastic, rubber, glass ete.

Q.2. Describe various methods of identification of hazards

Ans :- A "hazard" is any source f potential damage or harm or adverse health effect on something
as someone under certain condition of work. Basically hazard can cause harm as adverse health
effect (to individual as health effect an organization as property or equipment losses.
Main ideology of hazard identification is to identify all possible strings of events leading up to the
event life threatening the safety of the unit. The common methods of identifying hazard are:
HAZOP, FTA, ETA, EMEA etc.
i) The technique of HAZOP: One of the commonly used analytical methods,
otherwise known as the " technique of key words. The set of words used in the
hazard identification based on HAZOP techniques are: No an NOT, MORE, LESS,

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 PART OF, OTHER THAN, EARLY, LATE BEFORE, AFTER ete.. Hazop technique
can be applied to each stage of the construction as operation of the technology.
ii) The technique of FTA: The construction of fault tree starts from identification of
the effect of the event and passes in the direction of the events of earlier.
Indicates the possible combination of events that may lead to which is
specified. Event f events that tree is used for qualitative and quantitative
analysis.
The main steps in FTA :- i) Determine the initial events
ii) Determine the events in direct damage
iii) Construct of tree damage, using event leading logical gats
iii) ETA technique - Building of event tree analysis is leased on the graphical model
depicting the relationship of cause and effect in the event. Hazard identification
begins with determining the initialization event. The probability of the effect is
determined by multiplying by the probability of all the events.
ETA is method used to build the object model of probability for risk analysis.
Three two forms of this technique :
i) Before the accident and
(ii) After the accident.

iv) The technique of FMEA : It is used to determine. the damage, that have a significant impact on
the operation of the entire system. Evaluate the reliability of individual components of the
system. Analysis of the types and effect of damage to the FMEA is look up table elements of the
system, equipment their –Possible damage and effect on other components, systems or the state.
The propose of the FMEA is to identify specific short comings of the process and their exclusion
or minimize their effects.

Q.3. Write down the UN Classification of hazardous substances

Ans :- The hazardous substances divided by united Nation Committee of Expert
on the transport of dangerous goods into the following classes:
1) Class: Explosive
Division 1: Substances and articles which have a mass explosion hazard.
Devision 2: Substances and articles which have a projection hazardous but not a mass explosion
hazards
Division 3: Substances and articles which have a fire hazard and either a miner blast hazard or a
major projection hazard or both
Division 4: Substances and articles which present no significant hazard.
Division 5: very insensitive Substances which have a mass explosion hazard...
Class-2: Gases compressed, liquefied, dissolved under pressure or deeply refrigerated .
Class-3: Inflammable liquids
Class – 4 Inflammable solids, substances liable to spontaneous combination substances which on
contact with water emit inflamable gases.
Class-5 Oxidising substances organic peroxide.
Class-6: Poisonous and infections substances.
Class-7: Radioactive substances.
Class-8: corrosives
Class-9: Miscellaneous dangerous substance Arrangement for loading and unloading of the liquid
have to be well designed. It is preferred off to the load toxic and flammable material from the
bottoms. It is preferable to provide a discharge pump on the tank.
Q.4. write down the chemical safety in storage of bulk quantity

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Ans :- In order to fully understand the hazardous associated with stored chemicals we first need
to know what chemicals are being stored. Safe storage begins with an up to date inventory of a
chemical and knowledge of the hazards each posed by each chemicals .
The requirement of Generals storage of bulk quantity
1) All chemical must be stored in a safe, secure Location
2) store chemicals away from direct sunlight sources of heat and egress pathways.
3) Hazardous chemicals must be stored below eye level.
4) Do not store chemicals on the floor, window ledges or balconies.
5) keep containers closed unless we are dispensing a chemical or adding to the
container.
6) Provide secondary containment for liquids whenever possible..
7) label containers and be sure container is compatible with the chemical.
8) use rated storage cabinets or safety cans whenever possible.
9) Cold rooms, refrigerators and freezers have additional requirements, particularly
for flammables.
10)Chemicals should always be segregated according to their specific hazard to
prevent unintended reactions.

Examination –Internal Assessment

Paper Code-IS-203
Chemical Safety in Industry
Years- 2021-22

Total Marks -20 Time : 1 Hr

Note: Solve any Four Question

1) How to do emergency planning and preparedness with different hazards?

Ans :- Emergencies can create a variety of hazards for workers in the impacted area. Preparing
before an emergency incident plays a vital role in ensuring that employers and workers have the
necessary equipment, know where to go, and know how to keep themselves safe when an
emergency occurs. These Emergency Preparedness and Response pages provide information on
how to prepare and train for emergencies and the hazards to be aware of when an emergency
occurs. The pages provide information for employers and workers across industries, and for
workers who will be responding to the emergency.
The actions taken in the initial minutes of an emergency are critical. The first step when
developing an emergency response plan is to conduct a risk assessment to identify potential
emergency scenarios. An understanding of what can happen will enable you to determine
resource requirements and to develop plans and procedures to prepare your business. The
emergency plan should be consistent with your performance objectives.
Developing the Emergency Response Plan
1. Review performance objectives for the program.
2. Review hazard or threat scenarios identified during the risk assessment.
3. Assess the availability and capabilities of resources for incident stabilization including people,
systems and equipment available within your business and from external sources.
4. Talk with public emergency services (e.g., fire, police and emergency medical services) to
determine their response time to your facility, knowledge of your facility and its hazards and
their capabilities to stabilize an emergency at your facility.
5. Determine if there are any regulations pertaining to emergency planning at your facility; address
applicable regulations in the plan.
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 6. Develop protective actions for life safety (evacuation, shelter, shelter-in-place, lockdown).
7. Develop hazard and threat-specific emergency procedures using the Emergency Response Plan
for Businesses.
8. Coordinate emergency planning with public emergency services to stabilize incidents involving
the hazards at your facility.
9. Train personnel so they can fulfill their roles and responsibilities.
10. Facilitate exercises to practice your plan.

2) Explain bulk storages and safe entry procedures to confined spaces

Ans :- bulk storages :-Bulk storage is equipment and supplies stored in large quantities, typically
in a warehouse setting. Goods are often stored in original containers and without packaging. Bulk
storage may refer to liquid products such as petroleum or industrial supplies such as
construction materials. It can also refer to food storage. In general, bulk storage requires fewer
physical storage bins and allows for fast access to containers, with storage layout in blocks and
rows.
Types of Bulk Items & Containers
Storage Tanks, Vats, Drums & Silos – Ideal for liquid storage
Super Sacks – Typically for dry, flowable material. These can be stored on a pallet but with
caution due to weight, movement and product overhang.
IBC Containers – Intermediate Bulk Containers (IBC) are designed for a variety of materials from
food grade bulk liquids to hazardous materials.
Building Materials / Lumber
Large Equipment / Assembly Parts
Furniture / Appliances
safe entry procedures to confined spaces :- Generally speaking, a confined space is a fully or
partially enclosed space that:

is not primarily designed or intended for continuous human occupancy

has limited or restricted entrance or exit, or a configuration that can complicate first aid, rescue,
evacuation, or other emergency response activities
can represent a risk for the health and safety of anyone who enters, due to one or more of the
following factors:
its design, construction, location or atmosphere
the materials or substances in it
work activities being carried out in it, or
the mechanical, process and safety hazards present
Confined spaces can be found in almost any workplace. Confined spaces can be below or above
ground. A confined space, despite its name, is not necessarily small. Examples of confined spaces
include silos, vats, hoppers, utility vaults, tanks, water supply towers, sewers, pipes, access shafts,
truck or rail tank cars, aircraft wings, boilers, manholes, pump stations, digesters, manure pits
and storage bins. Ditches, wells, and trenches may also be a confined space when access or egress
is limited (but they still have “blue sky” above). Barges, shipping containers and fish holds are
also considered as possible confined spaces.

Tunnels Wells Manholes

Cold Storage Ship Holds Subcellars
Tanks Culverts Silos
Vaults Open Ditch
Many other situations or hazards may be present in a confined space. Be sure that all hazards and
risks are identified and controlled, for example:

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Any liquids or free-flowing solids should be removed from the confined space to eliminate the
risk of drowning or suffocation.
All pipes should be physically disconnected or isolation blanks bolted in place. Closing valves is
not sufficient.
Use two blocking valves, with an open vent or bleed valve between the blocking valves when
isolating pipelines or similar conveyances to prevent entry of materials and hazardous
contaminants.
A barrier is present to prevent any liquids or free-flowing solids from entering the confined
space.
The opening for entry into and exit from the confined space must be large enough to allow the
passage of a person using protective equipment.
Making sure no work is being performed outside of the space that could impact the safety or air
quality inside the confined space.
3) How you will achieve Pipeline safety?
Ans :- There are always risks involved when working with high-pressure equipment such as
pipelines. Some risks involved with pipeline handling include suspended loads and hazardous
terrains as well as the ubiquitous human error factor in operations. It’s essential for all personnel
to understand the required safety procedures to ensure proper and safe handling of equipment.
These procedures will help to minimize hazards and consequently, the rates of accidents on site.
Important Pipeline Safety Topics
Below are some critical safety precautions for working on pipelines.
1. Carry Out Frequent Safety Training
To raise awareness about on-site safety and reinforce learning in employees, employers should
schedule safety training frequently. During training, employees, supervisors, and managers
should all participate. Bolstered learning is an effective way to create a consistent mindset in
everyone.

All training carried out in the U.S. must comply with national standards and industry best
practices from recognized associations. For example, the American Gas Association provides
pipeline safety guidelines for enhancing pipeline safety in the natural gas industry.
2. Foster a Corporate Safety Culture
Safety is crucial at pipeline installations to prevent hazardous conditions that may cause harm to
employees. Safety must come before the job, and not the other way around. Managers and
supervisors have a responsibility to instill this consciousness in employees by showing the
example, giving rewards, and applying consequences where necessary.
All employees working on the site should possess STOP WORK authority to enable them to halt a
procedure they identify as unsafe.
3. Ensure Proper Pipeline Excavation Procedures
Proper pipeline excavation procedures must be followed judiciously to prevent hazardous
conditions at the site. Excavators used should be serviced as at when due and operators
adequately trained. Explosions or environmental contamination can occur when an excavator
damages an underground pipeline. Therefore, all utilities buried underground must be identified
and marked before commencing operations.
Operators can also call 181 to confirm when it is safe to begin excavation. Proper benching and
sloping techniques are essential during excavation. OSHA specifies that employees working in
trenches that are 5 feet deep or more (4 feet deep in some states) should use a Trench Protecting
System.
4. Use Appropriate and Adequate PPE While Working Onsite pipeline safety topics
When working with heavy equipment like pipelines, employees must use appropriate and
adequate personal protective equipment (PPE). Although PPE is widely considered to be the last

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line of defense against hazards, they can be the difference between a safe and an injured or dead
employee. Some parts of the body PPE should cover include the face (eyes), hands, and feet.
Standard PPE for ensuring onsite safety includes safety goggles, hard hats, safety boots (with
steel toes), and gloves. Every employee has a responsibility of managing their safety and that of
others by using appropriate PPE to mitigate risks while working with pipelines. PPE can be
especially important during pipeline cleaning services such as pipeline pigging or nitrogen
purging in pipelines where both equipment and chemical dangers are present.
5. Ensure Adequate Training for Operators of Heavy-Duty Machinery
All workers operating heavy-duty machines such as excavators, forklifts, and trucks should be
adequately trained and briefed on the correct job procedure and practices at the job site. Also,
place Operations and Maintenance manuals (OMMs) of the types of machinery they work with
within reach of employees at all …
There are always risks involved when working with high-pressure equipment such as pipelines.
Some risks involved with pipeline handling include suspended loads and hazardous terrains as
well as the ubiquitous human error factor in operations.
It’s essential for all personnel to understand the required safety procedures to ensure proper and
safe handling of equipment. These procedures will help to minimize hazards and consequently,
the rates of accidents on site.
4) Explain transportation of hazardous chemical with different mode of Transportation.
Ans :- Transporting chemicals and hazardous materials requires a process that must comply with
strict federal, state, and local regulations. The method also demands choosing the right coating
powerful enough to stop corrosion, ensure cargo purity, and maximize your uptime.
Who regulates hazardous material transportation?
The Hazardous Materials Transportation Act (HMTA) is the principal federal law regulating the
transportation of hazardous materials in the United States.
Its purpose is to "protect against the risks to life, property, and the environment that are inherent
in the transportation of hazardous material in intrastate, interstate, and foreign commerce"
under the United States Secretary of Transportation authority.
Hazards and Prevention When Transporting Chemicals
There are different modes of transportation in the industry and each requires safety standards
when transporting chemicals. We pulled together a checklist for transporting chemicals in each
mode of transportation.
 Over the Road Transport Hazards
 Rail Transportation of Dangerous Materials
 Transportation of Hazardous Chemicals by Water
5) Explain U. N. and other classification for Chemicals( Repeated)
6) Explain various points of Material Safety Data Sheet
Ans :- 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.
Following are the information that must be present on an MSDS:-
i) Product Information: product identifier (name), manufacturer and suppliers names, addresses,
and emergency phone numbers
ii) Hazardous Ingredients
iii) Physical Data
iv) Fire or Explosion Hazard Data
v) Reactivity Data: information on the chemical instability of a product and the substances it may
react with
vi) Toxicological Properties: health effects
vii) Preventive Measures

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vii) First Aid Measures
ix) Preparation Information: who is responsible for preparation and date of preparation of MSDS

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