Extinguishers

Classifications

Designed for the type of fire they are to extinguish. Must determine what is burning to select appropriately

Clean Agent

Designed to replace halogenated extinguishing agents. Discharged as a rapidly evaporating liquid that leaves no residue. Can be used for class A, B and C fires. Include: FE 36 Hexaflouropropane Hydrochloroflourocarbon (HCCF) Hydroflourocarbon (HFC) Perflourocarbon (PFC) Flouroiodiocarbon (FIC)

Common Portable Fire Extinguishers

Pump-type H2O Stored pressure H2O Water mist stored pressure Wet chemical stored pressure AFFF Clean Agent Carbon Dioxide (CO2) Dry Chemical Dry Powder

Class C ratings

There are no capability tests specifically conducted for C ratings Extinguishers for class C fires receive that letter rating because Class C are essentially an A or B fire involving electrical equipment. A class C rating confirms the agent used will not conduct electricity.

Fire Extinguishers Summary

Understanding classification, rating and use for extinguishers ensures: You can use a portable extinguisher You can instruct the business and residential communities on their appropriate use. Demonstrates professionalism in the fire service.

How are Portable Fire Extinguishers organized?

by the type of extinguishing agent as well as the method used to expel the contents.

Class A extinguishers

ordinary combustibles. Textiles Paper Plastics Rubber Wood water based agents.

Types of Portable Fire Extinguishers agents

1. Water 2. Carbon Dioxide 3. Foam (AFFF, FFFP, class A) 4. Clean Agents (halogenated) 5. Dry chemical (sodium bicarbonate, potassium bicarbonate, ammonium phosphate, potassium chloride.) 6. Wet chemical (Potassium Acetate) 7. Dry powder

Portable Fire Extinguishers: expelling methods

All portable extinguishers expel their contents using one of the following mechanisms: Manual pump Stored pressure Pressure cartridge

Stored pressure H2O

Also called air pressure (APW) or pressurized water (PW cans). Useful for all types of small class A fires. Water stored in a tank along with air or nitrogen. Can add class A foam concentrate to reduce surface tension making more effective. Due to the straight stream it has a long range of 30-40 feet.

Maintenance

Because they are pressurized, extinguishers must be hydrostatically tested. TFD hydrostatic tests portable extinguishers every 5 years. Test results must be affixed to the extinguisher shell.

Carbon Dioxide (CO2)

Both handheld and wheeled units . Most effective for Class B and C fires. Stored under it's own pressure as a liquefied gas and converts to a gas when discharged. Discharged through a plastic or rubber horn. Works by displacing the oxygen and smothering the fire. Very limited reach of 3-8 feet due to being discharged as a gas

Class K ratings

Capable of Saponifying vegetable, peanut, and canola oil. Wet chemical agents containing an alkaline mixture. -Potassium acetate -Potassium carbonate -Potassium citrate -Must be able to extinguish a deep fryer containing the light oils with a surface area of 2.25 square feet to meet the minimum criteria for a class K rating.

Portable Fire Extinguisher Classifications

Class A fires- ordinary combustibles. Class B fires- flammable and combustible liquids. Class C fires- Energized electrical. Class D fires- Combustible metals. Class K fires- Kitchen grease-laden equipment.

Aqueous Film Forming Foam (AFFF)

Class B extinguishing agent Suppresses vapors on flammable liquid spills. Air aspirating foam nozzle. Stored pressure from air or nitrogen. Do not spray directly on liquid spill, rain the agent down or deflect of nearby object.

Fire Extinguisher Ratings

Classified according to the types of fire for which they are intended. Alpha (A,B,C,D,K) Class A and B extinguishers are also rated according to performance capacity. Numeric Ratings are determined by the Underwriters Laboratories

Dry Powder

Designed for Class D fires. No single agent will control or extinguish fires in all combustible metals. Some are designed for several types of metal, other for one specific metal. Some powdered agents are applied with an extinguisher, while others are applied with a shovel or scoop. Designed to create a smothering blanket over the metal. Apply gently to avoid breaking the crust that forms over the metal.

Dry Chemical pt 2

Dry chemical agents are nontoxic however the cloud they create may reduce visibility and create a respiratory problem. May be mildly corrosive to all surfaces. Dry Chemical handheld units Can be either cartridge operated or stored-pressure A constant pressure of 200psi is maintained in the agent storage tank. Both will use either nitrogen or carbon dioxide as the pressurized gas.

Extinguishing agents methods to extinguish a fire:

Extinguishing agents use at least one of the following methods to extinguish fire: Smothering Cooling Chain Breaking Saponification

Pump type H2O

Ground cover fire or small class A fires Commonly used in wildland firefighting

Fire Extinguisher Ratings: Multiple markings

Identified by a combination of letters A, B, and or C Most common types Class A-B-C Class A-B Class B-C A 4-A 20-B:C should -extinguish a class A fire that is 4 times larger than a 1-A fire -approximately 20 times as much Class B fire as a 1-B extinguisher -Extinguish a deep-layer flammable liquid fire of 20 square feet -non conductive

How To Use

Inspect before use -external condition -Hose/nozzle -Weight -Pressure gauge Approach the fire from the windward side Use the PASS application

Overview

Most common fire protection appliances. Intended for use on small fires in the incipient or early growth stage. Multiple uses and sizes available.

Dry Chemical

Not the same as dry powder Designed for use in Class A, B, and or C fires The most common used portable extinguisher in use today Commonly used dry chemicals Sodium Bicarbonate Potassium bicarbonate Urea-potassium bicarbonate Potassium Chloride Monoammonium phosphate 2 types Regular B:C rated Multipurpose and A:B:C rated

Class A ratings

Rated from 1-A through 40-A For a 1-A rating, 1 ¼ gallons of water is required For a 2-A rating, 2 ½ gallons of water is required or twice the 1-A capacity

Class B ratings

Ratings from 1-B through 640-B Rating based on the approximate square foot of flammable liquid a non expert can extinguish with one full extinguisher. A non-expert is expected to extinguish 1 square foot for each numerical rating or value of the extinguisher.

Care

Shake dry chemical extinguishers monthly to loosen the agent and prevent it from settling Clean after each use Always recharge or refill fire extinguisher regardless of how much is used Store securely in the apparatus. Never drop Do not remove the safety pin until ready to use

Wet chemical stored pressure

Similar in appearance to PW cans. However are intended for use on class K fires. Contain a special Potassium based, low pH agent. Combine with oils to form a soapy surface know as saponification.

Water-Mist Stored-Pressure

Similar to stored pressure. However use deionized water as agent. Nozzles produce a fine spray instead of solid stream. Can be safe to use on class C fires.

Class D ratings

Testing varies depending on the metal being tested No numeric rating is given Instructions will be on the faceplate of the extinguisher.

Class K extinguishers

combustible cooking oils Vegetable oils Animal fats Oils that burn at extremely high temperatures. Wet chemical systems and portable Class K extinguishers

Class D extinguishers

combustible metals Lithium Magnesium Potassium Sodium Common uses of magnesium: -Wheels and transmission components -Some metal box springs (bed) -Identified by bright white light emitted during the combustion process. Dry powder extinguishers work best for these type fires.

Class C extinguishers

energized electrical equipment (non-electricity conducting) Carbon Dioxide Halon agents Once power is disconnected or turned off treat fire as a class A or B fire.

Class B extinguishers

flammable and combustible liquids. Alcohol Gasoline Lubricating oils Liquefied Petroleum Gas (LPG) Carbon Dioxide (CO2) Dry Chemical Class B foam

NFPA 10

requires extinguishers to be inspected a least 1 time each year. Check the inspection tag for last inspection. Check pressure gauge, weighing, and inspecting the agent level. Recharge if deficient in weight by 10%. Weight will be stamped on the neck. Inspect the discharge nozzles or horn. Check the hose for cracks or damage. Does the shell have physical damage? Are the operating instructions legible? Is it in the proper location?