SITING OF HAZARDOUS INDUSTRIES – ROLE OF RISK ANALYSIS 23 Oct 2010, Bengaluru, Karnataka Dr. A....
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Transcript of SITING OF HAZARDOUS INDUSTRIES – ROLE OF RISK ANALYSIS 23 Oct 2010, Bengaluru, Karnataka Dr. A....
SITING OF HAZARDOUS INDUSTRIES – ROLE OF RISK ANALYSIS
Dr. A. Koshy
23 Oct 2010, Bengaluru, Karnataka23 Oct 2010, Bengaluru, Karnataka
Capacity Building Programme on “New Techniques and Strategies in Prevention and Management of Industrial Disasters”
to the Karnataka Factory Inspectorate23-24 Oct 2010
Disaster Management Institute
ORGANIZERSORGANIZERSKarnataka State Safety InstituteKarnataka State Safety Institute®®
Department of Factories, Boilers, Industrial Safety & Health, BengaluruDepartment of Factories, Boilers, Industrial Safety & Health, BengaluruSPONSORSSPONSORS
ORGANIZERSORGANIZERSKarnataka State Safety InstituteKarnataka State Safety Institute®®
Department of Factories, Boilers, Industrial Safety & Health, BengaluruDepartment of Factories, Boilers, Industrial Safety & Health, BengaluruSPONSORSSPONSORS
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 ?
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.
Hazard Management in Life Cycle of an Engineering Project
PRODUCTION
DETAIL ENGINEERING
CONSTRUCTIONFRONT-END
ENGINEERING
INSTALLATION
COMMISSIONING
CONCEPT
Site Lay-out of installation
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
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
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.
• 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 - 300 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) 10 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 10036
Some key industrial accidents
Explosion at Chemical facility Flixborough, England, 1974
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 36. (Minimized as the office block was unoccupied)
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 -- 53 reported injuries.
Property in the surrounding area was damaged to a varying degree.
Contributing Factors 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
Explosion at Refinery, Pasadena, Texas 23 Oct 1989
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 4 Km
Contributing Factors Site and industry
standards for maintenance not followed
Training and competence
Work permit system - contractors
Positioning of occupied buildings
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
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
Layers of Safety in Industrial Project
Critical Radiation Levels
Damage Criteria for ExplosionOver pressure
(bar)Type of damage
0.30 Heavy0.20 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 damage0.03 Large & small windows usually
shattered0.02 10% window glass broken0.01 Crack of windows
Damage Contours from Pool fire at manifold
Effect Zone @ 12.5 kW/m2
Ellipse @ 12.5 kW/m2
Effect Zone @ 4 kW/m2
Ellipse @ 4 kW/m2
Radiation Level
Damage Contours from Jetfire at tank farm
Damage Contours from VCE
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.
Types of Dispersion
A distinction between different types of dispersion is made for the use of suitable models.
It is based on the type of material
Dispersions
Dense Neutral
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
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
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
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.
LPG TerminalMexico 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 500 people were killed and the facility was destroyed.
Contributing Factors
Plant layout - the positioning of vessels
Emergency isolation
Survivability of critical systems
Emergency plan and site access
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
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;
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- 1000 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
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
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
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.
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.
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.
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
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
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
IOC LPG Explosion Jaipur - Oct 12 ,2008
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
Risk Representation
Individual Risk Contour
1.0E-04
2.0E-05
5.0E-06
ALARP – As Low As Reasonable Practicable
1.0E-09
1.0E-07
1.0E-05
1.0E-03
1.0E-01
Ind
ivid
ual
ris
k (
IR)
Unacceptable region
The ALARP
Negligible risk
Broadly acceptable region
The lower the risk less proportionately, it is necessary to spend to reduce it. This concept of diminishing proportion is shown by the triangle
Tolerable only if risk reduction Is impracticable or cost is grossly disproportionate to the improvement gained
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 15646 2006
should be employed to decide the case