Ch. 7 Portable Fire Extinguishers
Aqueous Film Forming Foam (AFFF) Extinguishers
Class B fires, useful in combating fires in or suppressing vapors from small liquid fuel spills. Contains a specified amount of AFFF concentrate mixed with the water to produce a foam solution Air-aspirating foam nozzle that aerates the foam solution, producing a better-quality foam than a standard extinguisher nozzle provides.
Class D rating:
Class D agents cannot be given a multipurpose rating for use on other classes of fire.
Dry Powder Extinguishers
Class D combustible metals. Some applied with extinguisher, others applied with shovel or school. Create a smothering blanket
Wet Chemical Stored-Pressure Extinguishers
Class K fires, contain special potassium-based, low-pH agent formulated to operate on the principle of saponification in which the agent combines with the oils to create a soapy foam surface over the cooking appliance.
CO2 extinguishers are most effective in extinguishing _______________.
Class b and class c fires
Wet Chemical System
Extinguishing system that uses a wet-chemical solution as the primary extinguishing agent; usually installed in range hoods and associated ducting where grease may accumulate.
Water-Mist
In the fire service, water mist is associated with a fire extinguisher capable of atomizing water through a special applicator. Water-mist fire extinguishers use distilled water, while backpack pump-type water-mist extinguishers use ordinary water.
PASS application method:
Pull the pin, aim the nozzle at base of fire, squeeze the handles together to release the agent, sweep the nozzle back and forth to cover the burning material.
The method by which agents extinguish fire by oxygen exclusion is:
smothering
which of the following fire classifications would use the following agents for extinguishment: carbon dioxide, dry chemical and class b foam?
special hazard class b fires
Extinguishers for control and extinguish fires in deep fryers?
Wet Chemical stored-pressure extinguishers
Dry Powder
extinguishing agent suitable for use on combustible metal fires, Class D dry powder
Class C rating based on:
extinguishing agent will not conduct electricity.
Dry Chemical
extinguishing system that uses dry chemical as the primary extinguishing agent; often used to protect areas containing volatile flammable liquids. Used for Class A fires, class A foam.
Class B
flammable liquids; red square
Air-Aspirating Foam Nozzle
foam nozzle especially designed to provide the aeration required to make the highest quality foam possible; most effective appliance for the generation of low-expansion foam.
Pump-type water extinguishers are intended for use on ______________.
ground cover fires and also small Class A fires.
Whether a particular dry powder is applied with an extinguisher or with a scoop, it must be applied:
in sufficient depth to completely cover the area that is burning to create a smothering blanket.
Class A fire extinguisher rating
1-A through 40-A. 1-A is 1.25 gallons of water and 2-A is 2.5 gallons of water.
Class B fire extinguisher rating
1-B through 640-B; based on approximate square foot area of a flammable liquid fire a non-expert can extinguish.
remove extinguisher from service and replace if it is found to be deficient in weight by?
10%
Extinguisher with an air-aspirating nozzle that aerates the foam solution, producing a better-quality foam than a standard extinguisher nozzle:
AFFF extinguisher
what extinguisher prevents resignation by the vapor seal created by the film of water?
AFFF extinguisher
What extinguisher is suitable for use on Class A and Class B fires and is useful in combating fires in or suppressing vapors from small liquid fuel spills?
AFFF; aqueous film forming foam extinguisher
Halogenated Extinguishing Agents
Chemical compounds (halogenated hydrocarbons) that contain carbon plus one or more elements from the halogen series. Halon 1301 and Halon 1211 are most commonly used as extinguishing agents for Class B and Class C fires. Also known as halogenated hydrocarbons.
Water-Mist Stored -Pressure Extinguishers
Use deionized water as the agent and nozzles produce a fine spray instead of a solid stream. Class A extinguisher safe for Class C. Fine spray enhances cooling and soaking characteristics of water and reduces scattering of the burning materials.
Saponification
a phenomenon that occurs when mixtures of alkaline-based chemicals and certain cooking oils come into contact resulting in the formation of a soapy film. Potassium base, low pH.
Stored-Pressure Water Extinguishers
air-pressurized water (APW) extinguishers or pressurized water extinguishers, useful for all types of small Class A fires. Also used for extinguishing confined hot spots during overhaul operations.
Extinguishing Agent
any substance used for the purpose of controlling or extinguishing a fire.
Class B rating based on:
approximate square foot area of a flammable liquid fire that a non expert operator can extinguish.
fire codes require that portable extinguishers be inspected ____________.
at least once a year.
Factors in selecting proper fire extinguisher
atmospheric conditions, rating of the extinguisher, size and intensity of fire
the method by which agents extinguish fire by interrupting the chemical chain reaction is:
chain breaking
Most common combinations of portable fire extinguishers
class ABC, class AB, class BC
AFFF extinguishers
class B fires
Which of the following fires can be identified by the bright white emissions from the combustion process?
class d fires
which of the following fire classifications are extinguished by wet chemicals that are used in the extinguishing systems and portable extinguishers for these specific types of fires?
class k fires
Class K Ratings
class k rated extinguishers must be capable of saponifying oils. capable of extinguishing a fire with a 2.25 square feet surface area meet the minimum criteria.
What extinguisher is pressurized with argon gas and effectively cools and smothers fires in Class A and Class B fuels
clean agent extinguishers
highly sensitive computer equipment extinguishers:
clean agent extinguishers, multiple-use extinguishers, carbon dioxide extinguishers
Class D
combustible metals; yellow star
Class K
cooking oils; black hexagon
the method by which agents extinguish fire by reducing the burning material below its ignition temperature is:
cooling
what to check for on inspection tag?
date of previous inspection, maintenance or recharge
Dry Chemical Extinguishers
dry chem for use on Class A-B-C fires and/or Class B-C fires. Most common portable fire extinguishers used today. Common used dry chemicals: sodium bicarbonate, potassium bicarbonate, urea-potassium bicarbonate, potassium chloride, mono ammonium phosphate.
Extinguishers for use on class ABC fires and/or class BC fires and are among the most portable fire extinguishers in use today:
dry chemical extinguishers
Class A rating based on:
duration and range of the discharge and amount of extinguishing agent.
Class C
electrical equipment; blue circle
Clean agent extinguishers are useful for:
energized electrical equipment, computer equipment
Pump-Type Water Extinguishers
intended primarily for use on ground cover fires, also used for small Class A fires.
Carbon Dioxide Extinguishers
most effective on extinguishing Class B and Class C fires. discharge in gas form, limited reach and can be dispersed upwind. DO NOT TOUCH HORN BEFORE CHARGE HAS DISSIPATED, CAN RESULT IN SHOCK
Metal fire extinguishing agents
no single agent will control or extinguish fires in all combustible metals
Class A
ordinary combustibles; green triangle
Fire extinguisher
portable fire fighting device designed to combat incipient fires.
what extinguisher is intended for use on small class a fires only and are equipped with either a single or double acting pump?
pump-type water extinguishers
Clean Agent Extinguishers
replaces halogenated extinguishing agents. Effectively cool and smother Class A and Class B fuels and can also be used on Class C fires.
the method by which agents extinguish fire by forming an oxygen-excluding soapy foam is:
saponification
what extinguisher is used for extinguishing confined hot spots during overhaul operations
stored-pressure water extinguishers
Class D Ratings
test fires vary with type of combustible metal being tested. factors include: reactions between the metal and the agent toxicity of the agent toxicity of the fumes produced and the products of combustion time to allow metal to burn completely without fire suppression compared to the time to extinguish the fire using the extinguisher.
Class C ratings
tested for electrical nonconductivity. Class C rating confirms the extinguishing agent will not conduct electricity and is assigned in addition to the rating for Class A and/or Class B fires.
Clean agent extinguishers are approved by the US Environmental Protection Agency (EPA).
true
what extinguisher is safe to use on energized electrical equipment?
water-mist stored-pressure extinguishers
what extinguisher uses deionized water as the agent and nozzles that produce a fine spray instead of a solid stream?
water-mist stored-pressure extinguishers