PROTECTION, PREVENTION, & EXTINCTION

1. PROTECTION, PREVENTION, & EXTINCTION

2. O Agni, help us to gain prosperity by leading us on the righteous, redeem us from all our sins and actions. We bow before you with gratitude. -Rig Veda

3. RPL - JAMNAGAR Fire accident ( 26.10.2006 ) Property Damage of Rs.25 Cr

4. ONGC – BOMBAY HIGH ON SHORE RIG Fire accident ( 21.04.2004 ) Claimed 6 lives with pre mature closure of the Country’s prestigious On shore oil platform

5. HPCL VIZAG Fire accident (Sep‘15 1997 ) Claimed 51 lives & incurred a loss of about Rs 600 cr

6. And now a construction Site Can u Access the Lives lost ????

7. TOPICS • CHEMISTRY OF FIRE • HOW TO PREVENT FIRES.   • EXOTHERMIC & ENDOTHERMIC REACTIONS.   • HOW FIRES ARE INITIATED.   • KINDS OF FIRES AND ITS CLASSIFICATION. • MECHANISM OF EXTINGUISHING FIRES.   • FIRE EXTINGUISHING MEDIUMS.  

8. CHEMISTRY OF FIRE COMBUSTION Fire is combustion, a chemical reaction in which heat and light are produced. The rate it precedes is fast, because more energy is generated than can escape into the surrounding medium. This results in rapid acceleration of the reaction because of the build up of heat energy. OXIDATION When the rate of reaction is very slow only heat is produced and slow oxidation occurs, such as rusting. Combustion is rapid oxidation. FLAME Most combustion processes produce flame, which has the ability to spread through an atmosphere with the emission of heat and light. The flame front is a transition region separating burnt from un burnt gases, and light is given out from this region. A fuel oxidation mixture, which liberates enough energy on combustion to allow flame to spread through the unignited region of the mixture, is called “flammable”.

9. EXPLOSION The transmission from combustion to explosion is due to an acceleration of the reaction, caused either by the rise in temperature (thermal explosion). Generally explosions are of a chain/thermal nature that is a combination of the two causes where both heat accumulation and chain auto-acceleration contribute to the explosion.

10. THE FIRE TRIANGLE Combustion will continue as long as these three factors are present in the correct proportions. Removal of any one leads to the collapse of the triangle, combustion stops and it is the basic principle of fire prevention.

11. Fuel - SOLIDS, LIQUIDS AND GASES. The common solid and liquid fuels must emit vapor or gas before they can burn to produce a flame. Oxygen- Generally in the form of air. Air comprises approximately 79% Nitrogen. 20.7% Oxygen. 0.3% Carbon dioxide. Heat - Causing vaporization of the fuel providing a source of ignition from, sparks, arcs, naked flames, static electricity, sun, lighting a hot surface or a sufficient high temperature for spontaneous ignition.

12. DIFFERENT STAGES OF FIRE • INCIPIENT STAGENo visible smoke, flame, no significant heat  • SMOULDERING STAGECombustion increases develops smoke still no flame - heat also • FLAME STAGEFire develops further ignition occurs and flame starts • HEAT STAGE Large amount of Heat, Flame smoke & toxic gases produced Please Refer the Chain Reaction, which is the fourth factor in the tetrahedron

13. THE FIRE TETRAHEDRON FUEL CHAIN REACTION OXYGEN

14. EXOTHERMIC AND ENDOTHERMIC REACTIONS OF FIRE  Exothermic Reaction A Chemical reaction, which gives out heat in the process, is called exothermic reaction. Ex. When carbon is glowing a red heat, the combination of reaction of carbon with O2 is taking place. The process is depicted by the chemical reaction. C + O2 = CO2 + 10,890 British thermal unit for 12 oz of carbon. That is one atom of carbon and one molecule containing two atoms of O2 combines or reacts to form the molecule of CO2.The process is accompanied by liberation of a large quantity of heat.

15. Endothermic reaction. But when CO2 is passed over glowing carbon a chemical reaction takes place whereby, two atoms of CO2 are shared between two atoms of carbon to give a new gas Carbon monoxide (2CO), which is poisonous and flammable. This is represented by the chemical equation. C + CO2 = 2CO + 4,360 British thermal unit ABSORBED for 12 oz of carbon Further enormous quantity of heat is also absorbed in the process to an extent of 4360 British thermal unit for 12 oz carbon. This is called Endothermic reaction. C + CO2 = 2CO + 4,360 British thermal unit absorbed for 12 oz of carbon.

16. PYROLYSIS Decomposition brought about by heat. Common fuels must vaporize to burn, when heated they decompose to smaller molecules with greater volatility and flammability, and to carbon. It is vapor given off in the heating and decomposition process that burns. Because a certain amount of heat is necessary to vaporize a fuel, individual fuels have critical temperature relative to the ignition processes. IGNITION TEMPERATURES Flash Point- The lowest temperature at which a hydrocarbon liquid vaporizes and on application of ignition will ignite but not necessarily support combustion. Fire Point - The lowest temperature for a fuel at which sufficient Vapor is given off which on application of ignition will ignite and support combustion.

17. Spontaneous - The temperature at which a fuel will automatically Combustion ignites without an independent source of ignition. Automatic - The temperature at which a hydrocarbon liquid is Ignition heated and will automatically ignite without applying a source of ignition. EXPLOSIVE LIMITS The explosive limits are the proportions of fuel vapor and oxygen coming together, necessary for a fire or explosion to occur. The Lower Explosive Limit (LEL), and Upper Explosive Limit (UEL), are expressed as percentages by volumes of flammable vapors in air.

18. TRANSMISSION OF FIRE CONTACT CONDUCTION CONVECTION RADIATION

19. FIRE SPREAD Fire can spread by: Conduction - Heat traveling along or through conductive material eg. Unprotected steel girders. Convection - Fire spread by rising hot gases and smoke eg. Stair and lift wells. Radiation - Materials ignited when placed too close to a source of radiated heat eg. Electric fires. Direct burning- Combustible materials giving off sufficient vapor to encourage combustion and continue burning when coming into contact with a naked flame, eg.Chair or mattress being exposed to lighted cigarette.

20. CLASSIFICATIONS OF FIRES A CLASS Solid Combustible Materials such as WOOD, PAPER, FABRICS-CARD BOARDS (QUENCHING-COOLING) B CLASS Flammable oil such as COAL, OIL, GAS, GREASE, CHEMICALS LNG, LPG (BLANKETING-SMOTHERING) C CLASS ELECTRICAL (NON-CONDUCTING)

21. PRINCIPLES OF EXTINGUISHMENT Removal of one or more of the factors of the Triangle of Fire is the basic principles of fire prevention: Starvation - Removal of the fuel from the fire. Smothering - Limitation of oxygen from the fire. Cooling - Limitation of the heat below the ignition temperature.

22. FIRE EXTINGUISHERS Most fires are relatively small and can be easily extinguished. It is important that all employees are familiar with fire extinguisher distributed about the premises and the principles underlying their design, maintenance and use. Hand fire extinguishers are designed for small fires and therefore are used close to the burning material. Dry Chemical Powders The basis of most chemical powders is sodium bicarbonate, with the addition of a metal striate as water proofing agent, is widely used, not only in portable /wheeled extinguishers but also for general application in large quantities in DCP Fire Tenders.

23. Properties: Principle base chemical : Sodium bicarbonate Additive mixed with the powder : Metallic striates Tricalcium to prevent caking Phosphate hydrofobic Silicones. Particle size of the powder : 20 to 25 microns. Characteristics : a) Free Flowing b) Non-toxic and unlikely to give any environmental Problem c) Water repellent d) Non-conductor of Electricity Extinguishes Fire By : 1) Smothering 2) Cooling 3) Shielding Radiation of heat.

24. Dry Chemical Powder Extinguishers: This Consists of two types: 1) Gas Cartridge type: The Powder is expelled by pressure released into the body of the extinguisher from a CO2 gas cartridge 2) Stored Pressure type: The powder is expelled by pressure maintained in the body of the extinguisher by nitrogen or air.

25. DRY CHEMICAL POWDER EXTINGUISHER SAFETY CLIP Co2 CATRIDGE (INNER CONTAINER) RUBBER HOSE DRY CHEMICAL POWDER OUTER CONTAINER NOZZEL TO OPERATEE: KEEP EXTINGUISHER UPRIGHT. REMOVE SAFETY CLIP STRIKE KNOB. DIRECT THE POWDER AT THE BASE OF FIRE RECHARGE: IMMEDIATELY

26. DRYCHEMICAL HAND TYPES PIN CO2 CARTRIDGE NOZZLE VALVE VALVE NOZZLE VALVE BICARB. SODA POWDER TREATED TOMAKE WATERPROOF WHEEL TYPES

27. CARBON DIOXIDE FIRE EXTINGUISHERS CO2 LIQUID UNDER PRESSURE HOSE VALVE PIN HANDLE 2.5 LBS CYLINDER 20 LBS HORN CO2 Extinguishers In this type of extinguisher, the liquid CO2 is contained in a pressure cylinder and is released by a squeeze trigger mechanism through a horn type applicator.

28. CARBON DI-OXIDE (CO2) AS EXTINGUISHING MEDIA Properties Appearance : Colourless / Odorless Gas (White Cloudy – smoky appearance) Molecular Weight : 44 Density : 1.52 Vapour Pressure at 25OC : 58.24 bar Critical Temperature : 31.0OC Critical Pressure : 72.85 atm Boiling Point (Sublimes) : -78OC Latent Heat of Vaporization : 0.121 KJ/Kg

29. Foam Extinguishers • In this type of extinguisher, foam is produced from a foam solution. The foam concentrate is stored either as a solution or in water within the body of the extinguisher, or separately in a sealed inner container. • When the extinguisher is activated foam solution is expelled. Foam is produced in a miniature, self-aspirating foam branch at the end of the discharge hose. The types of concentrate which may be used are : • Protein • Fluoroprotein • Fluorochemical (AFFF) • The foam solution is expelled by pressure released into the body of the extinguisher from a CO2 cartridge (gas cartridge). • The foam solution is expelled by pressure maintained in the body of the • extinguisher by air or nitrogen (stored pressure).

30. FOAM TYPE EXTINGUISHER PLUNGER NOZZLE ALLUMINIUM SULPHATE SOLUTION ( INSIDE CONTAINER ) LEVEL INDICATOR SODIUM BICARBONATE SOLUTION ( OUTSIDE CONTAINER ) TO OPERATE 1. TAKE IT NEAR FIRE. 2. PULL THE KNOB AND TURN IT RIGHT AND LET IT REST ON THE CAP. 3. INVERT AND DIRECT STREAM TO FALL GENTLY ON FIRE. TO CHARGE 1. RECHARGE IMMEDIATELY AFTER USE. 2. AFTER DISCHARGE THIS EXTINGUISHER MUST BE WASHED OUT WITH FRESH WATER USING ATLEAST TWO CHANGES. 3. RECHARGE AT LEAST EVERY TWO YEARS.

31. FOAM AND ITS LIMITATIONS FOR USE ON LIQUID FIRES • Foam are not suitable for fires involving gases and light ends. • 2. Foam should not be used on materials, which are susceptible to water damage, and also materials like Sodium and Potassium reacts violently with water. • 3. Foam is a conductor and should not be used on energized electrical equipment fires. • 4. Foam is not effective on flowing liquid fires. • On hot oil/burning asphalt (which are above the boiling point of water) applying • foam may cause violent frothing and foaming over.

32. water as extinguishing media Water Water is still the most efficient, cheapest and most readily available medium for extinguishing fires of general nature. Techno-logical developments have produced additives to increase the efficiency of water as a fire extinguishing for specialized applications. Water is a Colorless Liquid Source : Easily available, cheap, relatively stable and heavy liquid can be transported easily from one place to another place. Specific Heat : 180 btu/lb Latent heat of Vaporization of Water : 970 btu/lb At ordinary pressure – water expands – 1700 times  Water extinguishes fire by : 1) Cooling 2) Smothering 3) Emulsification 4) Dilution

33. Aquamist and MicroDrop uses a range of droplet sizes to maximize penetration of the fire plume, and hence extinguishing performance. Large Droplets have the momentum to penetrate the fire plume, and will drag the smallest droplets into the combustion zone. Smaller Droplets surround the fire, and are pulled into the base of the fire as it draws in oxygen. The Smallest droplets cool the gases in the room, strip smoke from the air, and block the transfer of radiant heat. The end result is extinguishments, using considerably less water than a traditional water spray system.

34. S.No. SOURCES OF IGNITION (Descending order of frequency) EXAMPLES PREVENTIVE MEASURES 1 Electrical Equipment Electrical Defects due to poor maintenance mostly in wiring, motors, switches, lamps and hot elements. Use and approved equipment. Follow relevant code and establish regular maintenance. 2 Friction Hot bearings Broken machine parts Choking or jamming of material Poor adjustment Follow a regular schedule of inspection, maintenance and lubrication 3 Foreign substances Tramp metal that produces sparks when struck by rapidly revolving machinery Keep foreign material from stock. Use magnetic or other separators to remove tramp metal. 4 Open Flames Cutting and Welding torches (chief offenders) Gas and Oil burners Misuse of gasoline torches Follow established welding precautions. Keep burners clean and properly adjusted. Do not use open flames near combustibles. ANNEXURE-1 SOURCES OF IGNITION

35. 5 Smoking and matches Dangerous near flammable liquids and in areas where combustibles are used or stored. Smoke only in permitted areas. Use prescribed receptacles. Make sure matches are out. 6 Spontaneous ignition Deposits in ducts and flues Low-grade storage Industrial wastes Oily waste and rubbish Clean ducts and flues frequently. Remove waste daily. Isolate stored materials likely to heat spontaneously. 7 Hot Surfaces Exposure of combustibles to furnaces Hot ducts of flues Electrical lamps or irons Hot metal being processed. Provide ample clearances, insulation, air circulation. Check heating apparatus before leaving it unattended. 8 Combustion sparks Rubbish burning Foundry Copulas Furnaces and Fire boxes Process equipment Use incinerators of approved design. Provide spark arresters on stacks. Operate equipment carefully. 9 Overheated materials Abnormal process temperatures Materials in driers Over heating of flammable liquids Have careful supervision and competent operators, supplemented by well maintained automatic temperature control. 10 Static Electricity Dangerous in presence of flammable vapor Occurs at spreading and coating rolls where liquid flows from pipes. Ground equipment. Use static Eliminators. Humidify the atmosphere.

36. HOW TO USE A PORTABLE FIRE EXTINGUISHER Remember the acronym, "P.A.S.S." P - Pull the Pin. A - Aim extinguisher nozzle at the base of the flames. S - Squeeze trigger while holding the extinguisher upright. S - Sweep the extinguisher from side to side, covering the area of the fire with the extinguishing agent.

37. THANK U ALL