IFSTA CH 6 - Portable Fire Extinguishers

Question 1

fire extinguisher primarily intended use

Answer 1

for occupants to use on small, incipient fires or on fires in the early growth stage

Question 2

classifications of portable fire extinguishers

Answer 2

are classified according tot he type of fire that each is designed to extinguish

there are five classes (A, B, C, D and K)

certain extinguishing agents are only effective on certain classes of fire or fuels

Question 3

Class A

Answer 3

involve ordinary combustible such as:

textiles
paper
plastics
rubber
wood

Question 4

Class A fire extinguishers are rated

Answer 4

from 1-A through 40-A

primarily based on the amount of water and the duration and range of the discharge used in extinguishing test fires

Question 5

Dry chemicals

Answer 5

will also extinguish fires fueled by class A materials

Question 6

Class B

Answer 6

involve flammable and combustible liquids and gases

Question 7

Agents used to extinguish class B fires

Answer 7

include Carbon dioxide, dry chemicals and class b foam

Question 8

flammable and combustible liquids and gases include

Answer 8

alcohol
gasoline
lubricating oils
liquefied petroleum gas (LPG)

Question 9

Class B ratings range from 1-B through 640-B

Answer 9

the rating is based on the approximate square foot area of a flammable liquid fire that a nonexpert operator can extinguish using on full extinguisher

Question 10

Class C

Answer 10

involves energized electrical equipment

rating confirms that the extinguishing agent will not conduct electricity

Question 11

Class D

Answer 11

those involving combustible metals and alloys such as

titanium
magnesium
sodium
lithium
potassium

Question 12

Magnesium fires

Answer 12

can be identified by the bright white emissions during the combustion process

Question 13

Class D extinguishing agents

Answer 13

Dry powder

Class D extinguishers are only to be used on class D fires

Question 14

Class K

Answer 14

involve combustible cooking oils such as vegetable or animal fats and oils that burn at extremely high temperatures

wet chemical systems and portable fire extinguishers are used to control and extinguish class k fires

Saponification

Question 15

smothering

Answer 15

excluding oxygen from the burning process

Question 16

cooling

Answer 16

reducing the burning material below its ignition temperature

Question 17

chemical flame inhibition

Answer 17

interrupting the chemical chain reaction in the burning process

Question 18

saponification

Answer 18

forming an oxygen-excluding soapy foam surface

Question 19

manual pump extinguisher

Answer 19

the operator physically applies pressure to the pump that increases pressure within the container which forces the agent out a nozzle at the end of the hose

Question 20

stored pressure

Answer 20

compressed air or inert gas within the container forces the agent outa nozzle at the end of a hose when the operator presses the handle

Question 21

pressure cartridge

Answer 21

a separate cartridge on the side of the container contains an inert gas

when the operator punctures the cartridge seal, the expellant enters the container and forces the agent out a nozzle on the end of a hose

Question 22

pump-type water extinguishers

Answer 22

are intended primarily for use on ground cover fires although they may also be used for small class A fires

Question 23

stored-pressure water extinguishers

Answer 23

useful for all types of Class A fires

there are also useful for extinguishing confined hot spots during overhaul operations

Question 24

Stored-pressure water-mist extinguishers

Answer 24

used deionized water as the agent and nozzles that produce a fine spray instead of a solid stream

the deionized water makers these Class A extinguishers safe to use on energized electrical equipment

Question 25

stored pressure wet chemical extinguishers

Answer 25

they are intended for use on Class K fires involving cooking fats, grease and vegetable and animal oils in commercial kitchens

Question 26

Aqueous film forming foam (AFFF) extinguishers

Answer 26

are intended for class B fires they are particularly useful in combating fires in or suppressing vapors from small liquid fuel spills

Question 27

AFFF differ from stored-pressure water extinguishers in two ways

Answer 27

AFFF tank contains a specified amount of AFFF concentrate mixed with the water to produce a foam solution has an air-aspirating foam nozzle that aerates the foam solution, producing better quality foam than a standard extinguisher nozzle provides

Question 28

clean agent extinguishers

Answer 28

effectively cool and smoother fires in class A and B fuels and inhibit the sustained chemical reaction in class C fuels the agents are nonconductive and can extinguish energized electrical equipment fires halogenated extinguishing agents

Question 29

carbon dioxide extinguishers

Answer 29

are most effective in extinguishing class B and Class C fires

Question 30

Dry Chemical extinguishers

Answer 30

are for use on Class A-B-C and/or Class B-C fires

Question 31

dry powder agents are only for use on

Answer 31

Class D fires

Question 32

There are two basic types of dry chemical extinguishers

Answer 32

regular B-C rated Multipurpose A-B-C rated

Question 33

two basic designs for handheld dry chemical extinguishers

Answer 33

cartridge-operated stored-pressure

Question 34

cartridge-operated handheld extinguishers

Answer 34

employ a pressure cartridge connected to the agent tank

Question 35

stored-pressure handheld extinguishers

Answer 35

the agent stored tank maintains a constant pressure of about 200 psi

Question 36

wheeled units

Answer 36

Class A, B and C fires position the unit and then extend the hose

Question 37

Dry powder extinguishers

Answer 37

fires involving class D combustible metals require special dry powder extinguishing agents and application techniques

Question 38

selecting the proper fire extinguishers, consider

Answer 38

classification of the burning fuel hazards to be protected against atmospheric conditions ease of handling the extinguisher rating of the extinguisher size and intensity of the fire availability of trained personnel to operate any life hazard or operational concerns

Question 39

when inspecting an extinguisher immediately before use, check the following

Answer 39

external condition - no apparent damage hose/nozzle - in place weight - feels as though it contains the agent pressure gauge (of available)

Question 40

PASS application method

Answer 40

pull aim squeeze sweep