Fire Prevention & Control

• Our principle shall be ;

Definition of FIRE :--• Combustion reaction where heat and flame

is evolved.

FIRE = Flammable vapour or gas (FUEL)

+ Air in correct proportion (O2)

+ Source of ignition (Naked Flame)

+Chain reaction

Fire Chemistry

FUEL + O2 Heat CO2 + CO

Fire Chemistry

FIRE TRIANGLE

• FUEL : Vapour Stage• AIR : Oxygen• HEAT : Naked or Excess Temp.

Fuel

Ai

r

Heat

Fire Tree

• Heat stage - uncontrollable heat, large amount of smoke etc.

•Incipient stage - no visible smoke

•Smoking stage - visible smoke

•Flame stage - flame starts, smoke increases

Few Terminology• Flash point; It is the lowest temperature at

which the substance gives off sufficient vapour to be ignited at the surface. The concentration of vapour above this temp forms an ignitable mixture with air.

• Flammability limits: These limits give the range between the lowest and highest concentration of vapour in air that will burn or explode when an ignition source (such as a spark or open flame) is present. The concentration is generally expressed as percent fuel by volume.

Few Terminology• Fire Load; Amount of combustible matter

present that can act as a fuel to feed a hostile fire.

Unit - kg / m2. • Hot Work; Any work using open flames or

sources of heat that could ignite materials in the work area.

CLASS OF FIRE

Solid combustible materials such as

•Ordinary carbon matter;•Paper;•Wood;•Plastics etc.,

FIRE INVOLVING

Liquids such as * Oil* Petroleum* Solvents* Grease* Paints etc.,

FIRE INVOLVING

* L.P.G

* GASEOUS SUBSTANCE UNDER PRESSURE

FIRE INVOLVING

Minerals and metals such as, but not limited to;

•Magnesium

•Sodium

•Potassium

•Flammable metals etc.,

FIRE INVOLVING

METHODS OF EXTINGUISHING

STARVATION

STARVATION

* REMOVE FUEL

* VACATE PEOPLE

BLANKETING

* CLOSE THE AIR ENTRANCE

* TRAP THE SMOKE

* MAINTAIN THE SAME FOR SOME TIME

COOLING

COOLING

* CONTROL THE FLOW OF HEAT & THE CHAIN REACTION BY POURING WATER OR ANY OTHER COOLING MEDIUM

EXTINGUISHING MEDIA

• CLASS A (PAPER ,WOOD)- WATER

• CLASS B (OIL) - FOAM, DCP

• CLASS C (GASES) - DCP,CO2,

• CLASS D (METAL) - SP. POWDER

Fire Extinguishers Media

Water • High cooling capacity; • Non-toxic; • Inexpensive and readily available; • Effective on solid combustibles (Class A Fires); • Flammable liquids (Class B -45°C and above)

where it is applied as a spray; • Not effective on Class C fires; • Not to be used on Electric fires.

Foam • Due to its light weight, creates blanketing effect;• Shall be applied on the surface of a container of the liquid;• Cuts off oxygen supply and thus smothers;

Powder • Several chemicals used to make extinguishing powders.• Efficient in the extinction of Class A, B & C Fires.• Extinction of solids by forming a flame- retardant layer on the

surface of the material. • On Electrical Installations

– To be cleaned off;– Corrosion problem;

Fire Extinguishers Media

Gas • Gases used are carbon dioxide and

HALON agents, non-conductive gaseous agents and therefore are normally used for electrical fires;

• Do not leave undesirable residue;• Suitable for Class B fires and Class A fires

where these have not become deep-seated.

Fire Extinguishers Media

Fire Chart

Water / Cooling

Foam / Blanketing

Powder / Blanketing

Gas / Blanketing

ABC Stored

PressureClass "A", Solid fuelsClass "B" Liquid fuelsClass "C", Gas fuels Class "D", Metals Fires Intiated from electric

1st Option2nd Option

Not Suitable

Extingsuihing Agent / Principle

Type of Fuel

1) WATER TYPE 1. SODA ACID (Obsolete)2. STORED PRESSURE

2)FOAM TYPE1. Chemical 2. Mechanical

3)DRY CHEMICAL POWDER TYPE

4) CARBON DI-OXIDE TYPE

PORTABLE FIRE EXTINGUISHERS

Inner chamber (Aluminum sulfate)

Outer chamber(sodium Bi-carbonate)

Plunger knob

Mechanical Foam Type Fire Extinguishers

• Extinguishes by smothering method,

Construction• Aqueous Film Forming

Foam (AFFF) solution;

• CO2 expel the foam solution;

FOAM TYPE FIRE EXTINGUISHER

Capacity -9 ltrs./18ltr./150ltr.

Solution A -inner chamber (Aluminum sulfate)

solution B - outer chamber(sodium Bi-carbonate)

Foam ratio =8-9 times (Approx.. 72 lit.)

1)Remove the EXT. Keep a distance about 4-5 Mt.

2)Pull the plunger knob hard and invert the EXT.2-3 times.

3) Direct the jet of foam to cover the complete area.

DISCHARGE TIME - 1.1/2Minutes TO 2 Minutes

RANGE -4-6 m.

DRY CHEMICAL POWDER TYPE

Plunger knob

Cartridge

Discharge Hose

Dry Chemical Powder Type

Construction • Sodium bi carbonate

powder;

• CO2 Gas cartridge;

Operation• Remove the safety clip;• Hold the discharge hose

firmly and press the plunger;

• Na2CO3 will be thrown out;

Co2 Type Fire Extinguishers

Plunger knob

Co2 Gas

Carbon di-Oxide Type

• Extinguishes fire by smothering methods;

• Suitable for fighting;– Flammable liquids;

– Gases;

– Fires starting from electrical,

• Hold insulated part of the discharge horn;

CO2 FIRE EXTINGUISHER

Capacity: 2 / 4.5 / 6.8 / 22.5Kgs.

Liquefied Co2 at pressure of 64 kg/cm2 to 70 kg /cm2 at Temp. below 31oc

TO OPERATE

1. Remove the locking pin

2. Operate the wheel valve and direct thee jet of gas at the base of fire.

DISCHARGE TIME - about 30 sec.

Effective range- 1 to 1.5 m.

ABC Stored Pressure

• Stored nitrogen Gas;• Can be used for Class A,

B & C;• Smothering method of

Extinguishing;• But not a good substitute

of water for class A fire;

Operation of ABC Stored Pressure

HOW TO EXTINGUISH FIRE?

*STAND OPPOSITE TO THE DIRECTION OF THE AIR (facing the back)

*Attack on the Base of fire.

*Keep sufficient distances from the fire and move closer as the fire reduces.

Fire Prevention

Welding & Gas Cutting• Hot work area should be free from;

– Combustible materials for 10 m from work; (or)

– Should be separated by barriers of 1 hour fire resistance;

• Floor of Work area covered by sand ;• Hot work on Walls;

– Other side of the wall should be cleared from combustible;

• Floor openings and cracks;• Suitable fire extinguishers

– Bucket of sand;– Hose line or portable extinguishers;

• HOT WORK PERMIT• (Ref IS: 818 – 1968)

Common Accidents in Gas Cutting

Removing lid of the diesel drum;• Gas cutting increases the internal temperature,

resulting in expansion of gas consequently increasing the pressure;

• Gross calorific value of diesel – 46 x 106 MJ / KG;

Accident of Gas Cutting

Diesel / Petrol Storage

• Floors covered by sand;• Sand periodically removed and

covered with damp sand and water;

• No Smoking;– Will tiny spark be sufficient to ignite;

• Storing different chemicals differently;– Tagging chemicals;– Assume what will happen if Diesel is

replaced instead of Transformer coolant oil;

Gas Cylinder storage area

• No Smoking;– Will tiny spark be sufficient

to ignite;

• Storing different chemicals differently;– Tagging chemicals;

– Assume what will happen if Diesel is replaced instead of Transformer coolant oil;

Carpentry Shop

• Saw dust;• Wooden scarp;• Periodical disposal of dust;

P&M Workshop

• Waste cotton rugs;• Waste oil;• Disposing out of site;

Fire plan

• Fire Extinguisher source & layout;• Fire Barriers for Hot work;• Fire Watchers;• Hot work permit;

Inform time office or security or site safety personnel in case of any fire. Know the use of diff. Type of extinguishers. Never use water on an electrical or oil fire. Store inflammable materials in a closed container and in its assigned place. Clean immediately any spillage of inflammable liquids. Remove unwanted waste materials

DO’s

Smoke in prohibited areas. Store inflammables near any electrical switch boards. Obstruct the path leading to fire extinguishers or emergency doors wherever provided. Throw cotton waste soaked with inflammable liquids in the drains or room corners.

Don'ts

Fire Extinguishers

Inspection Checklist

Inspection checklist

1. Confirm the extinguisher is in its proper location; 2. Confirm the extinguisher is not obstructed; 3. All seals and pins are in place and have not been

removed or tampered with; 4. If applicable, check gauge to ensure that the pressure is

within the operable range; 5. Examine the extinguisher for obvious signs of physical

damage, leakage, corrosion or clogged nozzles; and6. Ensure that a current service tag is present on

extinguisher.

Dry Chemical Powder

Check For• Weight of the extinguishers, for powder mass;• Gas cartridge not less than 10%;• Operating mechanism;• Free movement and closing of discharge control. • Nozzle, hose, and vent holes, piercing mechanism of cap

cartridge holder, grease and wipe clean.• Remove the inner shell and clean portholes.• Caking, lumps and foreign matter, in Dry powder;• Body internally for any damage of corrosion.

Hazardous AreaThe Petroleum Rules, 2002

Hazardous area; • Petroleum having flash point below 650C or

any inflammable gas or vapour in a concentration capable of ignition is likely to be present.

• Petroleum or any inflammable liquid having flash point above 650C is likely handled, stored etc..

Classification of Hazardous AreaThe Petroleum Rules, 2002

Zone “O” area : if inflammable gas or vapour are expected to be continuously present in the area;

Zone “1” area: if inflammable gases or vapour are likely to be present in the area under normal operating conditions;

Zone “2” area: if inflammable gases or vapour are likely to be present in the area only under abnormal operating conditions or failure or rupture of an equipment.

Electric apparatus

Zone “0” area :• No electric apparatus shall be allowed in a zone “0” area;Zone “1” area :• Flame proof apparatus• Intrinsically safe apparatus approved by the chief controller of

explosives;• An industrial-type apparatus;

– Purging with a plenum of atmosphere free from significant concentrations of inflammable gas;

– Automatic cut off or a warning

Zone “2” area :• non sparking apparatus of a type approved by the chief controller;

FIXED FIRE FIGHTING INSTALLATIONS 1. FIRE HYDRANT SYSTEM 2. WATER SPRINKLERS SYSTEM 3.AUTOMATIC FIRE DETECTION SYSTEM

5.AUTOMATIC FIRE ALARM SYSTEM

THANK YOU