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Major Disasters
Fire Initiated Toxic Release
ANYTHING WITH POTENTIAL FOR PRODUCING AN ACCIDENT.
PROBABILITY OF HAZARD RESULTING AN
ACCIDENT.
HAZARD
RISK
Risk Management
Strategic Management
Operations Management
MAJOR FIRE RISK IDENTIFICATION
RISK ANALYSIS
TRANSACTIONAL DECISION YESNO
No Risk Management
Risk Control
Transfer Reduce Retain
For any Industrial Process Plant
Following questions must be asked and answered
1. What are the Hazards ?
2. What can go wrong and how?
3. What are the chances?
4. What are the consequences?
CONESQUENCES OF HAZARDOUS EVENT
•FIRE/ EXPLOSION
•VAPOUR CLOUD EXPLOSION
•FORMATION OF TOXIC ATMOSPHERE
Different Terminologies of Hazardous Situations
•Pool Fire
•Jet Fire
•Flash/ Cloud Fire
•Vapour Cloud Explosion (VCE)
•High Pressure Rupture
•BLEVE
•Release of Toxic Gases/ Liquids
Heat Radiation levels and Damage Effects
(As per API 521)
Radiation Level (kW/Sq.m)
Observed Effect
4.0 Sufficient to cause pain to personnel within 20 second
12.5 Minimum Energy required for piloted ignition of Wood and melting of Plastic Tubing
37.5 Sufficient to cause damage to Process Equipment
Explosion Over Pressure Level and Damage Effects
Overpressure (bar) Damage produced by Blast Effect
0.02 No considerable damage except shattering of few glass panes
0.13 Partial collapse of Buildings
0.20 Steel framed building distorted and pulled away from the foundation
THE FIRST STAGE OF RISK ASSESSMENT IN A PROCESS PLANT ESSENTIALLY CONSISTS OF THREE STEPS:
1. IDENTIFYING THE HAZARD
2. ESTIMATING THE EFFECTS OR CONSEQUENCES OF THE HAZARD
3. DETERMINING PROBABILITY OR LIKELIHOOD OF OCCURRENCE OF HAZARDOUS EVENT
THE NEXT STEP OF RISK ASSESSMENT
TO DETERMINE WHETHER EFFECTS OF THE CONSEQUENCE AND THE PROBABAILITY OF OCCURRENCE OF THE HAZARD IS WITHIN THE ACCEPTABLE LIMIT OR NOT.
HAZARD IDENTIFICATION METHODOLOGYHAZARDS IN PROCESS PLANTS ARE PRIMARILY IDENTIFIED BASED ON FOLLOWING INFORMATION:
•HAZARDOUS PROPERTIES OF MATERIALS
•TYPE OF UNIT PROCESS/ OPERATION
•OPERATING PARAMETERS
•ANY OTHER RELEVENT DATA
NFPA CODE NO. 325 M
CHECK-LIST
DOW INDEX
COMMONLY USED STRUCTURED HAZARD IDENTIFICATION TECHNIQUES
1. WHAT IF ? ANALYSIS:
• What if the Raw Material contains impurities?
• What if Cooling Water is Lost?
• What if the Vessel Agitation Stops?
• What if Power Supply Fails?
• What if the Temp./ Press. Sensor Fail?
• What if the Pump Stops? etc.
2. HAZOP STUDYGUIDE WORDS
• NO
• MORE
• LESS
• AS WELL AS
• PART OF
• REVERSE
• OTHER THAN, etc.
3. FAILURE MODE AND EFFECTS ANALYSIS (FMEA)
FMEA evaluates the ways in which an Equipment can Fail and the Effects of such Failures on an Installation
4. FAULT TREE ANALYSIS (FTA)
Deductive Reasoning Process
5. EVENT TREE ANALYSIS (ETA)
Inductive Process
RISK ACCEPTABILITY CRITERIA
Statistical Experience Shows•Chance of Death due to Risk of Driving, Flying or Smoking is 1 in 100000 or 10 –5
•Chance of Death from Lightning or Falling of Aircraft is around 10 –7 or 1 in 10000000
It is therefore generally accepted that the Risk of Death 1 in 100000 or 10 –5 per Year is Alarming.
Action needs to be taken to Reduce the Risk BELOW the level 1 in 1000000 or 10 –6 per Year and it is generally accepted without concern for Industrial People.
PROBABILITY ESTIMATION
Failure Rate data for Some Equipment
Equipment Failure Rate (Failures/ Year)
Process Pressure Vessel 2.7x 10 -3
Pressure Storage Vessel 1.8x 10 -3
Heat Exchangers 1.7x 10 -3
Fired Heaters 405x 10 –3
High Temperature vessel, except Fired Heater
7.4x 10 -3
Low Temperature Vessel 1.5x 10 -3
CONSEQUENCE ESTIMATIONSoftware Package Organisation
EFFECTS TNO, Netherlands
CISCOM CISRA, CLRI, CHENNAICHARM Radian CorporationPOOL FIRE/ BLEVE/ EXPLOSION Package
IIT, Kanpur
EAHAP Energy Analyst CorporationHASTE ERT Inc
SLAB Lawrence Livermore National LabTRACE Safer CorporationPHAST DNV TechnicaEx- TOOL Swiss Re
Public or Societal Risk
FN Curve for Societal Risk
Acceptable
Unacceptable
Reduction Desired
F.N. Lines
102 103
105
103
Nos. of Probable Fatalities N
Expected
Frequency
F
RISK CONTROL MEASURES
•Physical Protection
•Procedural Protection
•Educational Protection
Physical Protection•Strict & Rigorous approach in following the Relevant Standards , Codes & Practices
•Built in Safety Devices and Safety System
•Venting through Tall stacks
•Field Monitors for Different Toxic Gases
•Burning Waste gases in a Flare System
•Provision of Wind Cones
•Fire Proofing of Steel Structures
•PPE
•Passive Protection System
•Active Protection system
•Automatic Protection system
•Improved Waste Water Management
PROCEDURAL PROTECTION•Fire Emergency Procedure
•Disaster Preparedness Plan
•Mutual Aid Scheme
•No Smoking Policy
•Investigation of All Accidents
•Hazard Identification through Safety Committee, House Keeping Committee, Safety audit Committee
•Conducting Plant Survey, safety survey
•Work Permit System
•Statutory Requirement
•Safety Promotional Activities
Contd.
•Information notes on Unsafe conditions
•MSDS
•Annual Medical Check up of Employees
•Safe Start up & Shut Down Procedure
•Regular and Preventive Maintenance
•Periodic testing of Fire Fighting Appliances
EDUCATIONAL PROTECTION•Periodic Training Programme on Safety, Fire Safety and Hazardous properties of materials
•Mock Fire Drill
•Safety Manuals
•Health & Safety News Bulletins
•Safety Motivation schemes
•Plant Operating Manual
GROWING IMPORTANCE OF RISK MANAGEMENT DUE TO
•LEGISLATION
•CUSTOMER ATTITUDE
•SOCIETAL EXPECTATIONS
•MANAGEMENT ATTITUDES
The Science of Firevkx dk foKku
FIRE TRIANGLE
vfXu f=Hkqt
Hea
t rk
i@fp
axkj
hA
ir gok@vkD
lhtu
Fuel Toyu’khy inkFkZ
EXTINGUISHING MECHANISM
* STARVATION * SMOTHERING * COOLING
• It takes three things to cause a fire– Heat - something that is hot– Fuel - something that will burn– Oxygen - the air all around us
• If we take any one of these things away, the fire cannot survive
;fn ge fdlh ,d Hkqtk dks gVk nsxsa rks vkx cq> tk,xhA
vkx cq>kus ds rjhds
* Hkw[kk ekjuk * xyk ?kksVuk * BaMk djuk
Remember when we talked about the Fire Triangle?
• If you remove any one element, you prevent the chemical chain reaction that results from fire
• ;fn ge fdlh ,d Hkqtk dks gVk nsxsa rks psu fj,D’ku can gks tk,xk rFkk vkx cq> tk,xhA
Fuel - or something that will burn / Toyu’khy inkFkZ
Oxygen - or the air all around us
gok@vkDlhtu
• Removing Heat (Cooling/ BaMk djuk)– Control of
• smoking materials
• matches and lighters
• heating appliances
• candles
– Suppression• water cools a fire
And when we remove any one side of the triangle, like taking away the oxygen, the fire cannot survive
Fire Triangle • Removing Oxygen (Smothering/ xyk ?kksVuk)– Stop, drop and roll– Smothering action– Blanketing effect
• Removing Fuel (Starvation / Hkw[kk ekjuk)– Education messages
• good housekeeping practices
• storage of flammable liquids– in approved containers– away from heat sources
Hea
t
Oxygen/Air
FIRE TETRAHEDRON
FIRE EXTINGUISHING MECHANISM
STARVATION / Hkw[kk ekjuk SMOTHERING / xyk ?kksVuk COOLING / BaMk djuk CHAIN REACTION INHIBITION / psu fj,D’ku jksduk
FIRE EXTINGUISHING MEDIA
• WATER ikuh • CARBON DIOXIDE dkcZu Mkb vkDlkbM % lh- vks- Vw• DRY CHEMICAL POWDER MzkbZ dsfedy ikoMj • SAND jsr• FIRE FIGHTING FOAM Qkse vkx cq>kus dk• HALON ALTERNATIVES gSyksu ds le:i
Fire ClassesA Trash Wood Paper C Electrical Equipment / Flammable gas
B Liquids GreaseCOMBUSTIBLE
METALS
D
• Wood /ydMh• Cloth / diMk• Paper / dkxt• rubber• many plastics
• Gasoline / isVzksy
• Oil / rsy• grease
• tar
• oil-based paint
• lacquer
• energized electrical equipment fctyh ds midj.k
• flammable gases xSlsa• magnesium
• sodium
• potassium
• titanium
• zirconium
• other combustible metals /kkrq
Fire Classes (cont.)
K Cooking Media
• Recently recognized by NFPA 10.
• Fires involving combustible vegetable or animal non-saturated cooking fats in commercial cooking equipment. [kkus ds rsy esa vkx dks ,d vyx Js.kh nh xbZ gS ] ds Dykl Qk;jA
CLASS K FIRESCLASS K FIRES
CLASSES OF FIRE
1. CLASS “A” FIRE: - CARBONIOUS FIRE Toyu’khy Bksl oLrq EX.- WOOD, PAPER, COAL, PLASTIC, CLOTH, ETC EXTINGUISHING MEDIA: - WATER cq>k,a & ikuh ls
2. CLASS “B” FIRE: - FLAMMABLE LIQUID FIRE Toyu’khy nzo oLrq EX. – PETROLEUM PRODUCTS, GREASE, SOLVENT,PAINT, ETC EXTINGUISHING MEDIA: - FOAM, DCP cq>k,a & Qkse@MzkbZ dsfedy ikoMj ls
3. CLASS “C” FIRE: - INFLAMMABLE GAS FIRE / ELECTRICAL FIRE Toyu’khy xSls ,oa fctyh dh vkxA
EX. – LPG, METHANE, PROPANE, ACETYLENE, ETC EXTINGUISHING MEDIA: - DCP / CO2 cq>k,a & MzkbZ dsfedy ikoMj @lh-vks-
Vw ls
4. CLASS “D” FIRE: - METAL FIRE /kkrq dh vkx EX. – MAGNESIUM, ALLUMINIUM, ZINC, ETC EXTINGUISHING MEDIA: - SPECIAL DRY POWDER (TEC) cq>k,a & Lis’ky MzkbZ
dsfedy ikoMj ls
FIRE FIGHTING SYSTEM
1. FIXED FIRE FIGHTING SYSTEM• FIRE HYDRANT SYSTEM• FLOODING SYSTEM• MULSIFIRE SYSTEM• WATER SPRINKLER/ SPRAY SYSTEM• PORTABLE FIRE EXTINGUISHERS, ETC
2. MOBILE FIRE FIGHTING SYSTEM• FIRE TENDER• TRAILER PUMP, ETC
3. FIX-CUM- MOBILE FIRE FIGHTING SYSTEM• FOAM CHAMBER SYSTEM• FOAM POURER SYSTEM, ETC
PORTABLE FIRE EXTINGUISHERS fofHkUu izdkj ds NksVs vfXu’kked midj.k
1. WATER TYPE FIRE EXTINGUISHERS ikuh okyk vfXu’kked• CO2 CARTRIDGE TYPE• STORED PRESSURE
2. FOAM TYPE FIRE EXTINGUISHERS Qkse okyk vfXu’kked• MECHANICAL FOAM TYPE
3. DRY CHEMICAL POWDER TYPE MzkbZ dsfedy ikoMj okyk vfXu’kked
• CO2 CARTRIDGE TYPE• STORED PRESSURE TYPE
4. CARBON DIOXIDE TYPE FIRE EXTINGUISHERS lh-vks- Vw vfXu’kked
• STORED PRESSURE TYPE
WATER TYPE FIRE EXTINGUISHER ikuh okyk vfXu’kked
(STORED PRESSURE TYPE)SQUEEZE GRIPSAFETY CLIP/PINPRESSURE GAUGESIPHON TUBEPURE WATERDISCHARGE HOSE
NOZZLE
MECHANICAL FOAM FIRE EXTINGUISHER Qkse okyk vfXu’kked
PLUNGER
HANDLE
CO2 CARTRIDGE
FOAM MAKING
BRANCH
MECHANICAL FOAM FIRE EXTINGUISHER Qkse okyk vfXu’kked
(STORED PRESSURE TYPE)
SQUEEZE GRIPSAFETY CLIP/PINPRESSURE GAUGESIPHON TUBEDISCHARGE HOSEAFFF SOLUTION
FOAM MAKING BRANCH
DCP FIRE EXTINGUISHER MzkbZ dsfedy ikoMj okyk vfXu’kked
(CO2 GAS CARTRIDGE TYPE)
PLUNGERSAFETY PIN/CLIPCO2 CARTRIDGE PIERCER
CO2 CARTRIDGE
INNER CONTAINERDISCHARGE HOSESIPHON TUBEDCP
NOZZLE
CARBON-DI-OXIDE FIRE EXTINGUISHER lh-vks- Vw vfXu’kked
SAFETY PINWHEEL VALVE
HIGH PRESSURE DISCHARGE HOSE
CYLINDERHANDLE
DISCHARGE HORNSIPHON TUBELIQUEFIED CO2
Fire Emergency ResponseR RRescueescue
AAlarmlarm
CContainontain
EExtinguishxtinguish
A
C
E
Fighting the Fire
SSweep side to sideweep side to side
AAim low at the im low at the base of flamesbase of flames
SSqueeze thequeeze thehandlehandle
PPull the pinull the pinP
A
S
S
Flash point
• The flash point of a liquid fuel is the temperature at which vapour given off by fuel will ignite momentarily when an external flame is applied
• At flash point the liquid fuel vapour will not continue to burn
• Determines the risk in storing a given liquid fuel at given temperature
Fire point
• The fire point of a liquid fuel is the temperature at which vapour given off by fuel will ignite and continue to burn when an external flame is applied
• In most of liquid fuels, fire point is not as clearly demarcated as flash point
Ignition point
• The ignition temperature is the lowest temperature at which the liquid fuel will spontaneously combust in a normal atmosphere, such as a flame or spark.
• This temperature is required to supply the activation energy needed for combustion.
Flammability limit
• The minimum concentration of vapor of liquid fuel in air below which propagation of flame does not occur on contact with a source of ignition. This is known as lower flammability limit ( LFL).
• There is also upper flammability limit (UFL)
• Flammability is generally expressed as percentage of vapour volume in air
Flammability limit cont.
• If the vapour –air mixture temperature is higher, the LFL is reduced. increasing the temperature by 100 C decreases the LFL value about 8%.
• Lower flammability for HSD is approximately 9 %