To be effective an extinguisher: Must be readily accessible In working order Suitable for the hazard Large enough to control the size fire

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5 To be effective an extinguisher: Must be readily accessible In working order Suitable for the hazard Large enough to control the size fire

6 Class A: fires involving ordinary combustibles water, class A dry or wet chemical, foam, and mist A

7 Class B: fires involving flammable and combustible liquids B Extinguished by dry chemical agents, foam, clean agents, or carbon dioxide

8 Class C: fires involving energized electrical equipment Extinguished with nonconductive agents such as carbon dioxide, clean agents, mist, and dry chemical C

9 Class D: fire involving combustible metals Extinguished by Dry Powders Like sodium chloride which is a material used to cover the burning metals Class D is never assigned as multipurpose extinguisher D

10 Class K: fires that involve oils that are used in commercial cooking applications These materials have been taken out of the Class B classification K Extinguished with wet chemical

11 Extinguishers must be marked for which the class of fire they are rated One system uses colored shapes with the class letter in the shape NFPA 10 recommends pictographs indicating the fire class and the types of fires on which the extinguisher should not be used

12 EXINGUISHING PRINCIPLES Remove Oxygen Heat Fuel

13 EXTINGUISHER RATINGS Class A and Class B extinguishers will have a numerical rating designating the size fire an untrained person should be able to extinguish Class A extinguishers: rated from 1-A to 40-A - 1-A requires 1 1 / 4 gallons of water Class B extinguishers: rated from 1-B through 640-B Every 1-B rating corresponds to 1-square-foot of flammable liquid

14 CLASS C EXTINGUISHERS No tests are conducted for capacity ratings Extinguishing agent is tested for electrical conductivity

15 CLASS D EXTINGUISHERS No tests are conducted for capacity ratings Tests are conducted for specific metals for: Reactions between the metal and agent Toxicity of the agent Toxicity of any fumes produced Time to allow the fire to selfextinguish versus time to extinguish the fire

16 For a Class K rating, extinguishing agents must be able to extinguish a fire involving cooking oils with a surface area of 2.25 square feet

17 WATER FIRE EXTINGUISHERS Extinguisher Characteristics: Size: 2.5 gallons Discharge distance: feet Duration: seconds Method of expelling agent: pump or pressure

18 WATER FIRE EXTINGUISHERS Agent Characteristics: Freezing temperature: 32 o F High surface tension Needs expellant force Extinguishment principle: remove heat/cooling Class A fires only

19 WATER FIRE EXTINGUISHERS Advantages Absorbs large amounts of heat Can be used with specialized agents Limitations Conducts electricity Freezes High surface tension Reacts with certain chemicals

20 Dry Chemical Extinguishers Most Common Extinguisher Made Extinguisher Characteristics: Size: 2.5 to 350 pounds Discharge distance: 5-20 feet Duration: 8-25 seconds Method of expelling agent: cartridge/stored pressure

21 Dry Chemical Extinguishers Agents: Sodium bicarbonate: ordinary Potassium bicarbonate: Purple K Potassium chloride: Super K Monammonium phosphate: multipurpose, Tri-class

22 Dry Chemical Extinguishers Extinguishment principle: Breaking chain reaction Tri-class: smothering Uses: Class A: Tri-class Class B & C: all types

23 Dry Chemical Extinguishers Advantages Nontoxic Nonconductive Quick flame knockdown Limitations Breathing difficulties Insulating qualities Corrosive properties Not flash back resistive Chemicals not interchangeable Some not compatible with foam

24 CLEAN AGENT EXTINGUISHERS Clean agent extinguishing agents were designed to replace halogenated extinguishing agents (Halon 1211 and Halon 1301) Halon production was stopped in 1994 due to its effect on the ozone layer There is still limited halon production and much of the halon in use is recycled

25 CLEAN AGENT EXTINGUISHERS Extinguish fires through a chemical process which inhibits combustion Used for Class B and Class C fires and in areas with sensitive electronic equipment High expansion ratio Needs no expellant Nonconductive and noncorrosive

26 Carbon Dioxide Extinguishers Extinguisher Characteristics Size: 2.5 to 100 pounds Discharge distance: 3-8 feet Duration: 8-30 seconds Method of expelling agent: stored pressure

27 Carbon Dioxide Extinguishers Agent Characteristics: Normally a gas 1.5 times heavier than air Low temperature Can be stored as liquid Extinguishment principle: smothering Class B and C fires, limited effect on Class A

28 Carbon Dioxide Extinguishers Advantages Nonconductive Non-reactive No residue Limitations Visibility Noise Short range Dissipates rapidly Displaces oxygen

29 WET CHEMICAL STORED-PRESSURE EXTINGUISHERS Specifically designed to extinguish fires involving unsaturated cooking oils in deep dryers Contain a special potassium-based, low-ph agent for class A & K Fires

30 Foam Fire Extinguisher Contains: Water, Air, & Foam Concentrate Extinguishes A & B Fires Water Mist Extinguishers Contains: Deionized Water Extinguishes with Fine Water Droplets for A & C Fires

31 Types of Extinguishers Manual Pump / Pressure Cartridge Stored Pressure Which is the most common Contains an agent in a cylinder with an expellant gas Discharge handle and may have a gauge

32 Types of Extinguishers Stored Pressure Water CO 2 Dry chemical Halon Clean agents Dry powder Can you Match the extinguishers below with the Types above?

33 Types of Extinguishers Stored Pressure 2 Water 3 CO 2 1 Dry chemical 5 Halon 5 Clean agents 4 Dry powder

34 All obsolete extinguishers should be removed from service and replaced with approved extinguishers Soda water base with an acid expellant Carbon Tetrachloride was a common vapor agent used manual pump & fire grenade

35 Extinguisher selection depends on: Characteristics of the fuels present Potential severity of any fire Extinguisher location Extinguisher effectiveness Personnel available and experience to use the extinguisher Health and safety concerns

36 Installation and placement Extinguishers must be conspicuously located Must be readily accessible Should be located along normal travel paths, including exits Must not be blocked by storage or equipment Must be visible or the location marked conspicuously

37 Determine if extinguisher is full and if the pressure gauge reading in the operable range Check the locking pin and tamper seal to determine if it has been used or tampered with Check the inspection tag for the dates of the previous inspections, maintenance, and recharging

38 Examine for physical damage Nozzle obstructions Corrosion Mechanical damage Hose condition Horns for cracks and obstructions Hydrostatic testing

39 EXTINGUISHER OPERATION Pull pin Aim nozzle Squeeze handle Sweep nozzle

40 EXTINGUISHER SAFETY Check extinguisher before approaching Approach upwind Don t enter burn area Don t turn back on fire

41 Review 1. Know the 5 classes of fires and which fire extinguishers are rated for each class? 2. What are the principals of how to extinguish a fire? 3. How are all fire extinguishers rated? 4. List the different types of fire extinguishers? 5. What is the acronym for using a fire extinguisher and what does it stand for?

42 1. Know the 5 classes of fires and which fire extinguishers are rated for each class? Class A Ordinary / Water, Wet or Dry Chemicals, Foam, or Mist Class B Flammable Liquids / Dry Chemicals, Foam, Clean Agents, or CO2 Class C Energized Electric / Dry Chemical, Clean Agents, Mist or CO2 Class D Flammable Metals / Dry Powders Class K Cooking Oil / Wet Chemicals 2. What are the principals of how to extinguish a fire? By Removing any side of the fire tetrahedron; Remove Heat (Cooling), Oxygen (Smothering), Fuel (Starving) or by Inhibiting the Chemical Reaction. 3. How are fire extinguishers rated? A - 1 ¼ Gallons of water B - Per Square Feet C - If it will Conduct Electricity D - Metal Specific K-Cooking Oils 4. List the different types of fire extinguishers? Water, Dry Chemical (The Most Common Extinguisher), Clean Agents (Halon Type), CO2 (Carbon Dioxide), Wet Chemical, Foam, and Mist 5. What is the acronym for using a fire extinguisher and what does it stand for? PASS P-Pull the Pin A-Aim the Extinguisher S-Squeeze the Trigger S- Sweep at the base of the fire