1. Siting of Hazardous Industries – Role of Risk Analysis
Capacity Building Programme on
“New Techniques and Strategies in Prevention and Management of Industrial Disasters”
to the Karnataka Factory Inspectorate Oct 2010
Siting of Hazardous Industries – Role of Risk Analysis
Dr. A. Koshy Oct 2010, Bengaluru, Karnataka
ORGANIZERS
Karnataka State Safety Institute®
Department of Factories, Boilers, Industrial Safety & Health, Bengaluru
SPONSORS
Disaster Management Institute

2. Concerns and issues in Siting/ Layout
Strategic Principles in the determination of safe location and layout for a new or a expansion project
Key information to be considered before selecting a site location
How are siting issues managed when limited space is available?
How are security concerns in a new site addressed ?
Explain Siting and Layout
Industrial dev comes price

3. An Ideal Situation
A site location and layout that will minimize risk to the surrounding and community/ personnel and property while maximizing the ease of safe operation and maintenance.
Appropriate siting and layout establishes a foundation for a safe and secure operation.
Eg BPCL LPG sites established in and ( Policy in acquiring appropriate land )
Basis for Facility Siting and Layout
Building a new site or adding equipment to an existing one is often an exciting, but daunting, proposition. If it is done well, capital is well invested, goals are met, and the future looks promising. If it is done poorly, money may be wasted, goals unachieved, and the future could be unwittingly compromised
Appropriate siting and layout establishes a foundation for a safe and secure site. A site that is well laid out will have a lower risk level than a poorly laid out site. The potential for toxic impacts, fire escalation, and explosion damage will be lower. The risk to personnel and the surrounding community will be reduced. Additionally, maintenance will be easier and safer to perform. However, these benefits do not come without associated costs. Separation distances translate to real estate that costs money. Tradeoffs between initial capital investment, life cycle costs, and risk reduction are inherent in siting and layout decisions
site location and layout that will minimize risk to site and community personnel and property while maximizing the ease of safe operation and maintenance. This approach may reduce the total life cycle cost.

4. Hazard Management in Life Cycle of an Engineering Project
Site Lay-out of installation
Employing HAZID early in Project cycle
Understanding the hazards is the first step
Consists of three parts
Hazards of Materials
Process Design Basis
Equipment Design Basis

5. Hazard Techniques for Site evaluation
Techniques of Fire Explosion Index and Toxicity Index
Dow’s Index
Mond’s Index
Codes ( OISD)
Allowing objective spacing distances to be taken into account at all stages

6. Major Accident Hazard Group
“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.
THE MAJOR ACCIDENT HAZARD CONTROL RULES, 1997
Major accident means an ‘Uncontrolled Occurrence’ in the operation of a site which leads to severe or catastrophic consequences to people, assets, the environment and/or company reputation.
The consequences may be immediate or delayed and may occur outside as well as inside the site. There will also be a high potential for escalation.
Examples :
loss of containment of flammable and/or toxic fluids leading to fire, explosion and/or toxic injury
events resulting in structural failure which could lead to further progressive collapse
loss of stability of mobile offshore installation
well blowouts
Transport vessels colliding with installations used for bulk loading explosive, flammable or toxic substances.
service vessel colliding with or otherwise affecting offshore installations
other external hazards affecting offshore and onshore sites e.g. accommodation/work barges alongside fixed installations, helicopters and aircraft, road/marine product tankers
The definition of ‘Major Accident’ specifically excludes ‘Occupational Accidents’ which have bounded, albeit possibly severe or catastrophic consequences. This means that one or more pedestrian fatalities resulting from a road accident on a site (however regrettable and tragic) would not be defined as a ‘Major Accident’. Similarly, one or more fatalities resulting from a fall from a scaffolding platform (again regrettable and tragic) would not be defined as a ‘Major Accident’

7. Features of Well Laid out Site
The potential for toxic impacts, fire escalation, and explosion damage will be low.
The risk to personnel and the surrounding community will be reduced.
Maintenance will be easier and safer to perform.
However, these benefits do not come without associated costs.
Separation distances translate to real estate that costs money.

8. Some key industrial accidents
Flixborough (6/74) 28 fatalities - $167MM
Seveso (7/76) Contaminated countryside
Mex. City (11/84) 550+ fatalities - $26MM
Bhopal (12/84) 3M+ fatalities - 200M affected
Chernob. Nuc. Plt. (4/86) 31 fatalities mi2 evacuated
Piper Alpha Plat. (7/88) 165 fatalities
Pasadena, Tx. (11/89) 23 fatalities - $797MM
Channelview, Tx. (7/90) 17 fatalities - $14MM
Pemex, Mexico (7/96) Multiple fatalities - $253MM, $8MMM loss to economy
Petrobras, Brasil (6/2001) fatalities - $300MM
Toulouse, France (9/01) 29 fatalities, 20,000 homes damaged
* Large property damage losses (17th edition); M&M Protection Consultants; 1166 Avenue of the Americas, NY, NY

9. Hazard & Risk Assessment
IDENTIFY
Are people exposed to harm resulting from the company’s operations?
ASSESS
What are the causes, consequences & effects?
How likely is the loss of control?
What is the risk & is it ALARP?
CONTROL
Can the causes be eliminated?
What controls are needed & can they be effective?
RECOVER
Can the potential consequences & effects be mitigated?
What are the recovery measures required?
Are the recovery capabilities suitable & sufficient?

10. Explosion at Chemical facility Flixborough, England, 1974

11. Explosion at Chemical facility Flixborough, England, 1974
A large quantity of cyclohexane vapor was released when a 20” “makeshift” bypass pipe ruptured
The cyclohexane formed a flammable mixture and subsequently found a source of ignition.
The resulting massive vapor cloud explosion killed 28 workers, injured (Minimized as the office block was unoccupied)
At the Nypro(UK) site,
Accident summary
At about 16:53 hours on Saturday 1 June 1974 the Nypro (UK) site at Flixborough was severely damaged by a large explosion. Twenty-eight workers were killed and a further 36 suffered injuries. It is recognised that the number of casualties would have been more if the incident had occurred on a weekday, as the main office block was not occupied. Offsite consequences resulted in fifty-three reported injuries. Property in the surrounding area was damaged to a varying degree.
Prior to the explosion, on 27 March 1974, it was discovered that a vertical crack in reactor No.5 was leaking cyclohexane. The plant was subsequently shutdown for an investigation. The investigation that followed identified a serious problem with the reactor and the decision was taken to remove it and install a bypass assembly to connect reactors No.4 and No.6 so that the plant could continue production.
During the late afternoon on 1 June 1974 a 20 inch bypass system ruptured, which may have been caused by a fire on a nearby 8 inch pipe. This resulted in the escape of a large quantity of cyclohexane. The cyclohexane formed a flammable mixture and subsequently found a source of ignition. At about 16:53 hours there was a massive vapour cloud explosion which caused extensive damage and started numerous fires on the site.
Eighteen fatalities occurred in the control room as a result of the windows shattering and the collapse of the roof. No one escaped from the control room. The fires burned for several days and after ten days those that still raged were hampering the rescue work.

12. Damages ( Onsite and Offsite)
18 fatalities occurred in the control room as a result of the windows shattering and the collapse of the roof.
No one escaped from the control room.
Fires burned for several days and after ten days those that still raged were hampering the rescue work.
Offsite consequences reported injuries.
Property in the surrounding area was damaged to a varying degree.

13. Contributing Factors Plant layout - position of occupied buildings
Not following codes & operating procedures while introducing modifications
design codes, management of change procedures, maintenance procedures during recommissioning
Plant layout - position of occupied buildings
Control Room not designed for withstanding major hazards
Emergency plan not updated following modifications
UK COMAH regulation was introduced
Failings in technical measures
A plant modification occurred without a full assessment of the potential consequences. Only limited calculations were undertaken on the integrity of the bypass line. No calculations were undertaken for the dog-legged shaped line or for the bellows. No drawing of the proposed modification was produced.
Plant Modification / Change Procedures[1]: HAZOP
Design Codes - Pipework[2]: use of flexible pipes
No pressure testing was carried out on the installed pipework modification.
Maintenance Procedures[3]: recommissioning
Those concerned with the design, construction and layout of the plant did not consider the potential for a major disaster happening instantaneously.
Plant Layout[4]: positioning of occupied buildings
Control Room Design[5]: structural design to withstand major hazards events
The incident happened during start up when critical decisions were made under operational stress. In particular the shortage of nitrogen for inerting would tend to inhibit the venting of off-gas as a method of pressure control/reduction.
Operating Procedures[6]: number of critical decisions to be made
Inerting[7]: reliability/back-up/proof testing

15. Explosion at Refinery, Pasadena, Texas 23 Oct 1989

16. Explosion at Refinery, Pasadena, Texas 23 Oct 1989
During maintenance work on a reactor settling leg, a large release of flammable vapor occurred at the Phillips 66 chemical complex.
The result -- a massive vapor cloud explosion, followed by a series of further explosions and fires.
23 fatalities and 300 people injured. Extensive damage to the plant facilities
Metal & Debris as far as Km
Accident summary
At approximately 1:00 p.m. on the 23rd October 1989 Phillips’ 66 chemical complex at Pasadena, near Houston (USA) experienced a chemical release on the polyethylene plant. A flammable vapour cloud formed which subsequently ignited resulting in a massive vapour cloud explosion. Following this initial explosion there was a series of further explosions and fires.
The consequences of the explosions resulted in 23 fatalities and between 130 – 300 people were injured. Extensive damage to the plant facilities occurred.
The day before the incident scheduled maintenance work had begun to clear three of the six settling legs on a reactor. A specialist maintenance contractor was employed to carry out the work. A procedure was in place to isolate the leg to be worked on. During the clearing of No.2 settling leg part of the plug remained lodged in the pipework. A member of the team went to the control room to seek assistance. Shortly afterwards the release occurred. Approximately 2 minutes later the vapour cloud ignited.

17. Contributing Factors
Site and industry standards for maintenance not followed
Training and competence
Work permit system - contractors
Positioning of occupied buildings
Failings in technical measures
Both the company and industry safety required isolation by means of a double-block system or the use of blind flange. However, at a plant level a procedure had been adopted which did not comply with this.
Maintenance Procedures[1]: isolation
The accident investigation established that the single isolating ball valve was actually open at the time of the release. The air hoses to the valve had been cross-connected so that the air supply that should have closed the valve actually opened it.
Maintenance Procedures[2]: recommissioning
Site procedures laid down details that air hoses to valves were to be disconnected prior to maintenance work. This task was not carried out.
Maintenance Procedures[3]: training/competence, management/supervision
The site held a large inventory of flammable materials under high pressure yet it had no fixed gas detection system.
Leak / Gas Detection[4]: positioning of detectors
Ventilation intakes of buildings close to or downwind of the process plant were not arranged so as to prevent the intake of gas in the event of a release.
Plant Layout[5]: positioning of occupied buildings
An effective permit to work (PTW) for both company employees and contractors was not enforced by the company.
Permit to Work Systems[6]: working in hazardous areas
There was no dedicated fire water system. Firewater was drawn off from the process water system. This system was severely damaged in the explosions resulting in a loss of water pressure. The fire water pumps failed when the raging fires attacked their electrical supply cables. Of the three standby diesel pumps units, one was under maintenance and another ran out of fuel.
Active / Passive Fire Protection[7]: testing and inspection
Some concern was expressed as to the audible level of the emergency alarm. It was likely that individuals in certain parts of the plant were unable to hear the siren.
Warning Signs[8]: human factors
The intended control centre was damaged beyond use and telephone communications disrupted.
Emergency Response / Spill Control[9]: site emergency plan
The location of the control room, separation distances between plant and escape routes (particularly for administrative staff) were all criticised.
Plant Layout[10]: position of occupied buildings

18. Risk Factors in Site Selection
Risk to Population density around the site
( from choice hazardous material, equipment , activites)
Risk from Natural disaster occurrence (earthquake, flood, etc.)
Risk of non-availability of power, steam and water
HAZID report
Air, water and waste regulations and their complexity
Accessibility to raw materials and markets
Transportation
Siting permits and complexity of obtaining them
Interaction requirements in industrial developments
Labour availability and costs
Investment incentives

20. Plant Siting Safety Considerations
Buffer zone
Location of other hazardous installations in vicinity
Inventory of toxic and hazardous materials
Adequacy of firefighting water supply
Access to Emergency equipment
Availability of emergency response support from adjacent industries and the community
Weather extremes and prevailing winds
Location of highways, waterways, railroad and airplane corridors
Environmental and waste disposal restrictions during emergencies
Draining and grade slope
Maintenance and inspection
Prevailing winds and meteorological data

21. Layers of Safety in Industrial Project

22. Critical Radiation Levels
The dosage - response relation can be expressed by probit equation
Y = ln (t.I4/3) for lethality
where Y is the probit; t is the time (s) and I is the radiation heat intensity (W/m2)
The radiation intensities can be expressed as 1%, 50% and 99% fatality levels, using the duration and dosage relationship from the above equation.

23. Damage Criteria for Explosion
Over pressure (bar)
Type of damage
0.30
Heavy
0.20 to 0.27
Rupture of Oil storage tanks Possibility of damage to eardrums (Human)
0.20
Steel frame constructions distorted and pulled away from foundations
0.10
Repairable damage
0.03
Large & small windows usually shattered
0.02
10% window glass broken
0.01
Crack of windows

24. Damage Contours from Pool fire at manifold

25. Damage Contours from Jetfire at tank farm
Effect 12.5 kW/m2
kW/m2
Effect 4 kW/m2
4 kW/m2
Radiation Level
Damage Contours from Jetfire at tank farm

26. Damage Contours from VCE

27. Toxic Dispersion & Effects
Vapor clouds may give rise to large fires, explosions or toxic effects.
Other things being equal, toxic gas clouds are likely to be dangerous at much greater distances from the point of release than their flammable counterparts.
Dispersion is the process through which gases can travel long distances.
Two types of dispersion occur in industrial situations.

28. Types of Dispersion Dispersions Dense Neutral
A distinction between different types of dispersion is made for the use of suitable models. It is based on the type of material

29. Consequences from Toxic Gas Dispersion
A large toxic release may give rise to the following effects on human beings:
lethal injury
non-lethal injury
Irritation
Toxic gas releases may cause domino effects by rendering adjacent plants inoperable and injuring operators.
Prevention/mitigation by provision of automatic control systems using inherently safer principles and a suitable control room

30. Large Toxic Release The main mode of exposure is inhalation
The effects of a toxic release are estimated knowing the relationship between the concentration-time profile and the degree of injury
The product C of concentration and the time of exposure t, is called dosage and is directly calculated from the dispersion equation

31. Exposure Limits
Three agencies provide information regarding exposure limits, specifying safe levels of air borne contaminants
OSHA
The National Institute of Occupational Safety (NIOSH) and
The American Conference of Governmental Industrial Hygienists (ACGIH)
These 3 agencies have established guidelines and specific exposure levels of various contaminants
The greatest danger of overexposure to hazardous materials occurs through inhalation. Because of this, three agencies provide information regarding exposure limits, specifying levels of air borne contaminants that are considered safe. OSHA has established a list of 425 substances that are considered air contaminants, many of which are commonly found in the research lab. Each of these materials has associated with it a PEL or permissible exposure limit. In addition, there are two other authorities interested in measuring air contaminants - the National Institute of Occupational Safety (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH). These 3 agencies have established guidelines and specific exposure levels of various contaminants. The levels recommended by these agencies should be used as guidelines, and in addition, the PELs established by OSHA are considered legal limits with the power of the legal system behind them.

32. Protection from Domino/ Cascade Effects
Arranging separation distances such that damage to adjacent plants will not occur even in the worst case;
Provision of barriers e.g. blast walls, location in strong buildings;
Protecting plant against damage; e.g. provision of thicker walls on vessels;
Directing explosion relief vents away from vulnerable areas; e.g. other plants or buildings, roadways near site boundaries.
However, these measures may not provide practical solutions against missiles, and risk analysis may be required to prove adequate safety.

33. LPG Terminal Mexico City, Mexico 1984
A major fire and a series of catastrophic explosions occurred at the PEMEX LPG Terminal.
After the intial release, the first BLEVE occurred.
For the next 90 minutes, a series of BLEVEs followed as other LPG vessels violently exploded.
Approximetly people were killed and the facility was destroyed.
PEMEX LPG Terminal, Mexico City, Mexico. 19th November 1984
A drop in pressure was noticed in the control room and also at a pipeline pumping station. An 8-inch pipe between a sphere and a series of cylinders had ruptured. Unfortunately the operators could not identify the cause of the pressure drop. The release of LPG continued for about 5-10 minutes when the gas cloud, estimated at 200 m x 150 m x 2 m high, drifted to a flare stack. It ignited, causing violent ground shock. A number of ground fires occurred. Workers on the plant now tried to deal with the escape taking various action. At a late stage somebody pressed the emergency shut down button.
About fifteen minutes after the initial release the first BLEVE occurred. For the next hour and a half there followed a series of BLEVEs as the LPG vessels violently exploded. LPG was said to rain down and surfaces covered in the liquid were set alight. The explosions were recorded on a seismograph at the University of Mexico.

34. Contributing Factors Plant layout - the positioning of vessels
Emergency isolation
Survivability of critical systems
Emergency plan and site access
Failings in technical measures
The total destruction of the terminal occurred because there was a failure of the overall basis of safety which included the layout of the plant and emergency isolation features
Plant Layout[1]: positioning of the vessels
Isolation[2]: emergency isolation means
The terminal’s fire water system was disabled in the initial blast. Also the water spray systems were inadequate.
Active / Passive Fire Protection[3]: survivability of critical systems, insulation thickness, water deluge
The installation of a more effective gas detection and emergency isolation system could have averted the incident. The plant had no gas detection system and therefore when the emergency isolation was initiated it was probably too late.
Leak / Gas Detection[4]: gas detection
Hindering the arrival of the emergency services was the traffic chaos, which built up as local residents sought to escape the area.
Emergency Response / Spill Control[5]: site emergency plan, access of emergency vehicles

35. Guidance values for safe separation distances
For prevention of Domino Effects
Thermal radiation from fire (Jet/ Flash/ Pool/ Fireball)
12.5 kW/m2 1% Fatality level
4.5 kW/m2 Safe for firefighters
Overpressure from Explosion (UVCE/ VCE/ BLEVE)
0.1 bar 1% Fatality level

36. The Criteria for Fatalities

37. Plants/Flammable storages should be sited in the open air
Site Factors to be considered where Risks of release of flammable/ toxic materials exists
Plants/Flammable storages should be sited in the open air
Locating all high-volume storage of flammable / toxic material well outside process areas;
Hazardous area classification (HAC) to designate areas for elimination of ignition sources .
Locating hazardous plant away from main roadways through the site;
Fitting remote-actuated isolation valves where high inventories of hazardous materials may be released into vulnerable areas;
Provision of ditches, dykes, embankments, sloping terrain to contain and control releases & limit safety & environmental effects;
in the open air so that minor leaks or thermal outbreathing can be dissipated by natural ventilation.
Maintenance procedures should include the displacement of vapours from hazardous areas before work begins
Buildings should be designed so that all parts of the building are well ventilated by natural or forced ventilation.

38. Incident at POL Depot, Jaipur, 29th Oct 2009, 6:10 pm
Liquid Motor Spirit had gushed out, when the tank was being lined up (made ready for pumping to BPCL) because MOV connecting to the tank was also open when the Hammer Blind was in the changeover position
Product leaked for 75 minutes tons of MS= 20 tons TNT before explosion took
After explosion, fire occurred in 9 of the 11 tanks and the fire continued till the fuel contents were totally burnt.
60000KL product burned out in 11 day
11 fatalities, many injured and 280 cr loss
3 Operators and 1 shift officer present at site
The accident was the non-observance of normal safe procedure involving sequence of valve operation in the line up activity and an engineering design which permitted use of a “Hammer Blind Valve”.
Hammer Blind Valve is a device which is used for positively isolating a pipeline. The design of the Hammer Blind valve allows a large area at the top of the valve (at the valve bonnet) to be completely open every time the when valve position needed to be changed.
It was through this open area that the liquid MS had gushed out, when the tank was being lined up (made ready for pumping to BPCL) because MOV connecting to the tank was also open when the Hammer Blind was in the changeover position
Product leaked for 75 minutes tons of MS= 20 tons TNT before explosion took
After explosion, fire occurred in 9 of the 11 tanks and the fire continued till the fuel contents were totally burnt. Two MS tanks which did not ignite immediately caught fire after a few hours. These two tanks experienced seal fire and their roof was not blown
60000KL product burned out in 11 day
11 fatalities, many injured and 280 cr loss
Loss of primary containment
Loss of secondary containment
Inadequate mitigation measures
Shortcomings in design and engineering specifications
Defunct Vital emergency shutdown system
Absence of Operating Personnel in Vital area
Absence of On-site and Off-site Emergency Measures
UNCONTROLLED LOSS OF PRIMARY CONTAINMENT IN THE FORM OF A JET OF GASOLINE
Wrong Operation of valves by operator
Improper Equipment (Hammer Blind valve)
Absence of Second Operator
Lack of supervision
Operating personnel incapacitated

39. LOSS OF SECONDARY CONTAINMENT
Open condition of dyke valve in tank dyke
drainage system is connected to storm water drain also which is open to atmosphere, Hydrocarbon entering this allows vapor to spread throughout installation.
INADEQUATE MITIGATION MEASURES
MOV closure from control room was malfunction
Non availability of SCBA
No emergency plan for the scenario
No emergency responder
SHORTCOMINGS IN DESIGN AND ENGINEERING SPECIFICATIONS
Selected device (HBV) for positive isolation is potentially hazardous ( open to atmosphere while in operation)
Operating area was inside dyke for MOV and HBV
Operating area access/escape unsatisfactory
MOV was used for tank isolation as well as for Hammer Blind isolation. No fall back provision
Push buttons of MOV’s too close to each other
Locations of push buttons difficult to see while standing in front of MOV
Approachability of valves poor, very congested
Fire water, fire pumps & storage tanks – water adequacy norms not based on major fire explosion. Location of five pumps and FW storage not ideal
Bleed valve between HOV and MOV not provided even though on P&ID
Second escape route from installation near pipeline area was blocked by a wall which had been constructed to close the gate
Restricted VHF communication facility, paging facility for operating staff and no Public Address System

40. Critical factors to be considered in plant layout
Location of control room /Protection
Fire water tank and fire water pump house
Congestion in the plant site because of buildings, structures, pipelines, trees etc.
The emergency exit gate shall be away from the main gate and always be available for use for personnel evacuation during emergency.
Evacuation routes should not be blocked by poor plant layout
Extract from IOC Fire Accident Report 10.5 Plant Layout
The control room should be located far away from potential leak sources as far as practical. Otherwise, the control room should be made blast proof.
Fire water tank and fire water pump house should be located far away from potential leak sources/tankage area.
Locate buildings and structures in the upwind direction (for the majority of the year) as far as practicable.
Avoid congestion in the plant site because of buildings, structures, pipelines, trees etc. The location of these individual facilities should be decided based on Quantitative Risk Assessment.
All buildings which are not related to terminal operation shall be located outside the plant area. This includes the canteen also where any spark or open flame may exist.
Wherever the tank terminal site also have pipeline division operational area in the same site, the control rooms for both the tank terminal and pipeline shall be located in the same operational building.
The emergency exit gate shall be away from the main gate and always be available for use for personnel evacuation during emergency.

42. Positioning of occupied buildings
The distance between occupied buildings and plant buildings( w.r.t dangers of explosion, fire and toxicity).
Locate buildings and structures in the upwind direction
Congestion in the plant site because of buildings, structures, pipelines, trees etc.
All buildings which are not related to terminal operation shall be located outside the plant area. (eg. canteen, ignition sources)
Personnel with more general site responsibilities should usually be housed in buildings sited in a non-hazard area near the main entrance.
In all cases occupied buildings should not be sited downwind of hazardous plant areas.

43. HPCL-Vizag refinery explosion 14th September 1997
Fire broke out at 6:15 am, following a suspected leak in the LPG pipeline from the Vizag port to the storage farm.
It caused a series of explosions, and soon spread to at least six other naphtha and petrol tanks.

44. Damages ( HPCL Refinery Fire )
Affected the entire product terminal area, including 11 storage tanks containing naptha, petrol, diesel, kerosene and furnace oil, besides the six ''Horton spheres'' containing LPG.
The refinery's administrative building, its canteen and some other buildings came crashing down like a pack of cards
Even an earthquake measuring eight on the Richter scale would not have caused so much damage.

45. What to do in case of Restricted Space- Case study of Fire at IOC filling station (petrol bunk)
Gas tanker filling underground tanks of the LPG outlet suddenly caught fire, Caused by leakage of LPG from a nozzle of a gas tanker
3 persons were killed and a dozen others injured
The fire engulfed a gas tanker, an electricity transformer and three cars and spread to a nearby multi-storey apartment building.
Ignition followed by Fire - spread to nearby houses and burnt trees and damaged electricity poles and wires.
Estimate about 12 to 15 tonnes of fuel went up in flames with the fire raging for six hours

46. IOC LPG Explosion Jaipur - Oct 12 ,2008
Entire gas station was engulfed in flames
Explosion took place in the tanker itself, destroying it completely. , the impact of which was felt in the entire Shastri Nagar residential area up to a distance of three kilometres
After 15 minutes of the gas that had leaked , the tanker blew off.
The rear shell of the tanker had been thrown 250 feet and made a big hole into an building
tanker exploded at that time and huge flames that were thrown out of it 350 feet away
Forensic officials suspect that after refueling, starting of the tanker by Saleem and Meena might have led to the explosion.
eyewitness accounts that some welding work was undergoing within the pump premises due to which leaked gas caught fire
seeing the flames coming out of the pump.
tanker exploded at that time and huge flames that were thrown out of it
350 feet away
First, the gas that had leaked caused small flames of fire. After 15 minutes, the tanker blew off.
The rear shell of the tanker had been thrown 250 feet and made a big hole into an underconstruction building
Initially the company's own employees were deployed for the shifting of gas from the tankers to the pumping stations . But gradually with the number of pumps supplying LPG going up, the company adopted a policy of outsourcing

47. Risk Analysis Need to Be Applied
Helps in
Forecasting any unwanted situation
Estimating damage potential of such situation
Decision making to assess the suitability of sites
Evaluating effectiveness of control measures

48. IOC LPG Explosion Jaipur - Oct 12 ,2008

49. Risk The probability of suffering a harm or loss.
A combination of hazard and Probability
Risk = Probability of occurrence of hazard X magnitude of hazard
Measurement of Risk
Individual Risk
Societal Risk

50. Risk Representation
Individual Risk Contour
1.0E-04
2.0E-05
5.0E-06

51. ALARP – As Low As Reasonable Practicable
Tolerable only if risk reduction
Is impracticable or cost is
grossly disproportionate to
the improvement gained

52. Summary & Conclusion
Poorly laid out site increases risk of an accident especially in MAH group of Industries
Site layout factors should be considered during Plant Layout design phase
Risk and Damage contours (based on consequence Analysis) helps to demarcate hazardous areas
Risk analysis may be required to decide the project when there is restriction of space.
Risk levels criteria as stipulated in IS should be employed to decide the case