Chp 7 Portable Fire Extinguishers
Examples of flammable and combustible liquids and gases are :
Alcohol, gasoline, lubricating oil's, and liquefied petroleum gas
Stored pressure water extinguishers are intended primarily for use on:
All types of small class a fires and extinguishing confined hotspots during overhaul operations
Class do you fires can be identified by the:
Bright white emissions during the combustion process
Define halogenated extinguishing agents:
Chemical compounds that contain carbon plus one or more elements from the halogen series. Holland 1301 and Helen 1211 are most commonly used as extinguishing agent for class B and class C fires.
What is the class name for ordinary combustibles?
Class A
Water mist stored pressure extinguishers are primarily used on:
Class A fires and class C fires
What is the class name for cooking oil's in the kitchen?
Class K
Wet chemical stored pressure extinguishers are primarily used for:
Class K fires
What class fire is in bulk combustible cooking oil such as vegetable or animal fats and oils that burn at extremely high temperatures?
Class K fires
Dry chemical agents are used for what fires?
Class a BC fires and/or class BC fires
Do not confuse dry powder extinguishers with:
Dry chemical units
Class B fires involve:
Flammable and combustible liquids and gases.
Define air-aspirating foam nozzle:
Foam nozzle especially designed to provide the aeration required to make the highest quality foam possible.
Portable fire extinguishers are identified in what two ways?
Geometric shapes of specific colors with the class letters shown with in the shape and pictographs.
Pump type water extinguishers are intended primarily for use on:
Ground cover fires and small class A fires
The two most common Helen extinguishing agents are:
Halon 1211 and Halon 1301
What are commonly used dry chemicals?
Sodium bicarbonate Potassium bicarbonate Urea - potassium bicarbonate Potassium chloride Monoammonium phosphate
AFFF Is most effective on:
Static pools of flammable liquids
What kind of extinguisher describes compressed air or in North gas within the container forcing the agent out of a nozzle at the end of a hose when the operator press is the handle?
Stored pressure
What is the letter symbol for combustible metals?
The letter D in a yellow star
What is the letter symbol for cooking oils in a kitchen?
The letter K in a black hexagon
Fire extinguishers are classified according to :
The type of fire for which they are intended
Portable fire extinguishers are classified by the:
Type of fire they are designed to effectively extinguish
what do you use to remove dirt, Greece, foreign materials from a fire extinguisher?
Use warm water and soap
Define wet chemical system:
Usually installed in range hoods and associated ducting where grease may accumulate.
What cannot be used on class C fires until the electrical energy has been eliminated?
Water and water based agents
Define deionized water:
Water from which ionic salts, minerals, and impurities have been removed by ion exchange.
Class a fires can easily be extinguished with:
Water, water based agents such as class A foam, or dry chemicals.
Common uses of magnesium are in :
Wheels and transmission components for automobiles and even some metal box springs in beds.
Define saponification:
When mixtures of alkaline based chemicals and certain cooking oils come into contact resulting in the formation of a soapy film.
How much water is required for a 1-A rating?
1 1/4 gallons (5 L)
Then, a layer of powder how many inches deep should be spread nearby and the burning metal shoveled onto this layer with more powder as needed?
1 to 2 inches
Fire fighter one level must know the following about portable fire extinguishers:
1) classification of types of fires 2) risks associated with each class of fire 3) Operating methods of portable fire extinguishers 4) limitations of portable fire extinguishers
Fire fighter one level must be able to:
1) select appropriate extinguisher for size and type of fire 2) safely carry portable fire extinguishers 3) approach fire with portable fire extinguishers 4) operate portable fire extinguishers
Class a portable fire extinguishers are rated from:
1-A through 40-A based on the amount of extinguishing agent.
Class B ratings range from:
1-B through 640-B
What capacity are carbon dioxide wheeled units usually at?
50 to 100 pounds
Define Water-mist:
A fire extinguisher capable of atomizing distilled water through a special applicator.
How often are portable fire extinguishers removed from service for maintenance?
Annually
Define extinguishing agent:
Any substance used for the purpose of controlling or extinguishing a fire.
Aqueous film forming foam should not be:
Applied directly onto the fuel
How does carbon dioxide put out a fire?
By displacing available oxygen and smothering the fire. It has little to no cooling effect.
Define corrosive:
Capable of causing corrosion by gradually eroding, rusting, or destroying a material.
Both types of extinguishers use what two possible things as the pressurizing gas?
Carbon dioxide or nitrogen
Agents used to extinguish class B fires are :
Carbon dioxide, dry chemical, and class B foam
What are the two basic designs for handheld dry chemical extinguishers?
Cartridge operated and stored pressure
What term is used to describe interrupting the chemical chain reaction in the burning process?
Chain breaking
The three most common combinations are:
Class ABC, class AB, class BC
What is the class name for flammable and combustible liquids and gases?
Class B
Carbon dioxide extinguishers are most effective and extinguishing what class of fires?
Class B and class C fires
Aqueous film forming foam (AFFF) extinguishers are primarily used on:
Class B fires and fires from small liquid fuel spills
What is the class name for electrical equipment?
Class C
AFFF is Not suitable for fires in:
Class C, class D, or class K fuels
What is the class name for combustible metals?
Class D
Agents capable of extinguishing a fire from a deep fryer using these light oils with a surface area of 2.25 ft.² meet the minimum criteria for:
Class K rating
Once the power supply for a class C fire has been turned off or disconnected, the fire can be treated as a :
Class a or B fire
Class C fires are essentially :
Class a or class B fires involving energized electrical equipment
What are the five classes of portable fire extinguishers that match the five classes of fire?
Class a, B, C, D, and K
Dry chemical wheeled units are used on what class fires?
Class a, B, and C fires
What is a good choice for areas where highly sensitive computer equipment is located?
Clean agent or carbon dioxide extinguishers
Clase de fires are those involving:
Combustible metals and alloys such as lithium, magnesium, potassium, and sodium
Halon extinguishing agent are affective for extinguishing fires in
Computer rooms, aircraft engines, areas that contain materials that could easily be damaged by water or dry chemical agents
The class C rating confirms that the extinguishing agent will not:
Conduct electricity
What term is used to describe reducing the burning material below its ignition temperature?
Cooling
Water mist extinguishers use what as the agent and nozzles that produce a fine spray instead of a solid stream?
Deionized water
What extinguisher works best on class D fires?
Dry powder
What extinguisher controls and extinguishers fires involving clase de combustible metals?
Dry powder extinguishers
Class C fires involve :
Energized electrical equipment
How often should the dry chemical extinguishing agent be emptied and the extinguisher refilled?
Every six years
When inspecting an extinguisher, check the following:
External condition, hose/nozzle, weight, pressure gauge
Define dry powder:
Extinguishing agent suitable for use on combustible metal fires.
Do not select dry chemical extinguishers for use in areas where:
Highly sensitive computer equipment is located
Foam floats on the surface of fuels that are:
Lighter than water
Carbon dioxide is stored under its own pressure as a:
Liquefied gas
What kind of extinguisher describes when the operator physically applies pressure to a pump that increases the pressure within the container, forcing the agent out of a nozzle at the end of a hose?
Manual pump
All portable fire extinguishers expel their contents using one of what three mechanisms?
Manual pump, stored pressure, pressure cartridge
What describes procedures for the hydrostatic testing Distinguisher cylinders?
NFPA 10
Define dry chemical:
Often used to protect areas containing volatile flammable liquids.
What area is a non-expert operator expected to extinguish for each numerical rating or value of the extinguisher rating?
One square foot
Dry powder agents are use on what type of fire?
Only class D fires
Class Dnagents cannot be given a rating for use on:
Other classes of fire
Define fire extinguisher:
Portable fire fighting device designed to combat incipient fires.
If a small amount of burning metal is on a combustible surface, the fire should first be covered with :
Powder
What kind of extinguisher describes compressed inert gas contained in a separate cartridge on the side of the container and when the operator punches the cartridge, the expelling enters the container forcing the air out a nozzle on the end of a hose?
Pressure cartridge
What does PASS stand for when using a fire extinguisher?
Pull, Aim, Squeeze, Sweep
What should you do after using a fire extinguisher regardless of the amount of agent used?
Recharge or refill
What are the two basic types of dry chemical extinguishers?
Regular B:C rated Multipurpose and A:B:C rated
If anything is found wrong with the extinguisher what do you do?
Remove, replace, report
What term is used to describe forming an oxygen excluding soapy foam surface?
Saponification
What are three factors that determine the value of a fire extinguisher?
Service ability, accessibility, simplicity of operation
Portable fire extinguishers are intended to be used on:
Small fires in the incipient or early growth stage
What is the term used to describe excluding oxygen from the burning process?
Smothering
What four methods do extinguishing agent used to extinguish fires?
Smothering, cooling, chain breaking, saponification
Examples of ordinary combustibles are:
Textiles, paper, plastics, rubber, and wood
What is the letter or symbol for ordinary combustibles?
The letter A in a green triangle
What is the letter symbol for flammable liquids?
The letter B in a red square.
What is the letter or symbol for electrical equipment?
The letter C in a blue circle
Class A fires involve:
ordinary combustibles
