Fire Safety Chapter 7 Flashcards

Questions and Answers

A Class A fire extinguisher with a numerical rating of 2 contains _____ of water.

2.5

A Class B foam extinguisher is effective on all of the following fuels except one. Choose the exception.

Gasoline

Cooking oil (correct)

Diesel

Propane

What must a Class C agent do?

not conduct electricity

A Class C extinguisher is rated for use on:

energized electrical equipment Signup and view all the answers

What is the effect of a Class K agent on the fuel?

saponification Signup and view all the answers

What is a loaded stream extinguisher designed to do?

resist freezing Signup and view all the answers

A portable fire extinguisher is best suited for which situation?

fire in a wastebasket Signup and view all the answers

What is a potential problem with applying a multipurpose dry chemical agent to a Class K fire?

neutralization of other agents applied to the fire Signup and view all the answers

According to NFPA standards, the maximum floor area that can be protected by each extinguisher is specified according to:

occupancy type Signup and view all the answers

All fire extinguishers are classified according to:

the classes of fire on which they are effective Signup and view all the answers

All portable fire extinguishers use which means for expelling their contents?

pressure Signup and view all the answers

Bromochlorodifluoromethane is a _________ agent.

halogenated Signup and view all the answers

Class B foam fire extinguishers are also effective on:

Class A fires Signup and view all the answers

Class D agents work primarily by:

forming a crust over the fuel Signup and view all the answers

Combustion begins when a fuel is heated to its:

ignition point Signup and view all the answers

Dry chemical extinguishers may be used on Class C fires because they:

do not conduct electricity Signup and view all the answers

For an area to qualify for the classification of 'light hazard,' most of the combustibles present must be:

arranged so that fire is unlikely to spread Signup and view all the answers

For an extinguishing agent to be rated for a particular class of fire, it must:

prevent rekindling Signup and view all the answers

For the purpose of extinguisher selection and placement, a woodworking shop is a(n) __________ hazard environment.

extra Signup and view all the answers

For the purpose of extinguisher selection and placement, light hazard environments may contain a limited amount of combustibles of which class?

B Signup and view all the answers

For the purpose of extinguisher selection and placement, what is an example of a light hazard environment?

classroom Signup and view all the answers

For the purpose of extinguisher placement, what is the relationship between occupancy use category and hazard classification?

they are not necessarily related Signup and view all the answers

How do multipurpose dry chemical agents prevent rekindling of Class A fuel?

by forming a crust over the fuel Signup and view all the answers

If a private residence has a single fire extinguisher, where should it be located?

kitchen Signup and view all the answers

In general, the maximum discharge range of a CO2 extinguisher is:

8ft(2.5m) Signup and view all the answers

Requirements for placing and mounting portable fire extinguishers are found in NFPA:

10 Signup and view all the answers

The hydrostatic test interval for a dry chemical extinguisher with a stainless-steel shell is every _____ years.

5 Signup and view all the answers

The production and use of Halon extinguishing agents is limited because they are:

harmful to the earth's ozone layer Signup and view all the answers

The traditional symbol for a Class D fire extinguisher is a(n):

yellow star Signup and view all the answers

The weight of carbon dioxide is about ___________ times the weight of air.

one-and-a-half Signup and view all the answers

The 'P' in the acronym PASS, used in reference to fire extinguisher operation, stands for:

pull Signup and view all the answers

To qualify as a light hazard for the purpose of extinguisher selection and placement, the majority of materials in the area must:

be noncombustible Signup and view all the answers

What does a rating of 40 on a Class B extinguisher mean?

sufficient extinguishing power for 40 square feet of burning fuel Signup and view all the answers

What does it mean when a fire extinguisher has a pictograph with a red slash through it?

use on that class of fire could be unsafe Signup and view all the answers

What expels the extinguishing agent from a pump tank water extinguisher?

manual effort Signup and view all the answers

What is an advantage of portable fire extinguishers over hose lines?

faster deployment Signup and view all the answers

What is the best way to extinguish a Class C fire?

shut off the power and treat it as a Class A or B fire Signup and view all the answers

What is the difference between dry powder and dry chemical extinguishing agents?

each is rated for a different class of fire Signup and view all the answers

What is the most commonly used extinguishing agent for Class A fires?

water Signup and view all the answers

What is the primary extinguishing mechanism of halogenated agents?

disrupting the molecular chain reaction Signup and view all the answers

What is the term for a water-soluble flammable liquid?

polar solvent Signup and view all the answers

What is the term for the substance that puts out the fire?

extinguishing agent Signup and view all the answers

What residue does a CO2 fire extinguisher leave when discharged?

none Signup and view all the answers

When approaching a fire with an extinguisher in hand, you should always have a(n):

exit route Signup and view all the answers

Which agent is rated for use on Class A fires?

ammonium phosphate Signup and view all the answers

Which class of fire extinguisher includes a number in its classification?

A Signup and view all the answers

Which class of fire includes cloth?

A Signup and view all the answers

Which class of fire includes combustible cooking oils and fats?

K Signup and view all the answers

Which class of fire includes combustible metals?

D Signup and view all the answers

Which class of fire includes flammable and combustible liquids?

B Signup and view all the answers

Which class of fire involves energized electrical equipment?

C Signup and view all the answers

Which class of fire is depicted in the pictograph system by a burning trash can next to a wood fire?

A Signup and view all the answers

Which class of fire is depicted in the pictograph system by a fire in a frying pan?

K Signup and view all the answers

Which class of fire is depicted in the pictograph system by a flame and an electrical plug and socket?

C Signup and view all the answers

Which class of fire is depicted in the pictograph system by a flame and gasoline can?

B Signup and view all the answers

Which compound is added to a water extinguisher to improve penetration of fuel?

wetting agent Signup and view all the answers

Which extinguishing agent is approved for use in a Class K system?

wet chemical Signup and view all the answers

Which extinguishing agent is suitable for use on a Class C fire?

carbon dioxide Signup and view all the answers

Which extinguishing method is being used when a foam blanket is placed over the surface of a burning liquid?

cutting off the oxygen supply Signup and view all the answers

Which fire extinguishing agent is best for use on sensitive electronic equipment?

carbon dioxide Signup and view all the answers

Which hazard category includes automotive service or repair facilities?

extra Signup and view all the answers

Which is a disadvantage of CO2 extinguishers?

A disadvantage of carbon dioxide fire extinguishers is that it is not suitable for outdoor use, or in environments exposed to windy conditions. Signup and view all the answers

Which is a primary factor when determining hazard classification for extinguisher selection and placement?

amount of combustibles present Signup and view all the answers

Which is one of the three basic components required for fire?

heat, O2, fuel Signup and view all the answers

Which is the most appropriate use for a portable fire extinguisher?

Situations in which the use of water is not recommended Signup and view all the answers

Which is used to pressurize a stored-pressure water extinguisher?

compressed air Signup and view all the answers

Which motion best accomplishes the removal of the pin and tamper seal from a portable fire extinguisher?

twisting motion Signup and view all the answers

Dry chemical agents are not subject to freezing.

True Signup and view all the answers

There is no numerical rating for a Class K extinguisher.

True Signup and view all the answers

A dry chemical extinguisher should be serviced and recharged after any discharge.

True Signup and view all the answers

The specific agent must be matched to the specific fuel in Class D extinguishing.

True Signup and view all the answers

Which test is required to measure the ability of an extinguisher cylinder to withstand steady internal pressure?

hydrostatic testing Signup and view all the answers

Study Notes

Fire Extinguisher Classifications and Ratings

Class A fire extinguisher with a rating of 2 contains 2.5 gallons of water.
Class B foam extinguishers are ineffective against cooking oils.
Class C extinguishers are for energized electrical equipment and must not conduct electricity.
Class K extinguishing agents utilize saponification to affect fuels.

Fire Extinguisher Functionality

Loaded stream extinguishers are designed to resist freezing.
All portable fire extinguishers operate by release through pressure.
Class B foam extinguishers can also tackle Class A fires.
Dry chemical extinguishers do not conduct electricity, making them suitable for Class C fires.

Fire Hazard Classifications

NFPA standards dictate maximum floor area covered by extinguishers based on occupancy type.
Light hazard areas must have combustibles arranged to minimize fire spread.
Extra hazard environments, like woodworking shops, require careful extinguisher selection due to increased combustibles.

Extinguishing Techniques and Agents

Multi-purpose dry chemical agents can neutralize other agents on Class K fires.
For a single extinguisher in a private residence, placement is best in the kitchen.
CO2 extinguishers typically have a maximum discharge range of 8 feet (2.5m).
Halogenated agents extinguish fires through disrupting molecular chain reactions.

Fire Extinguisher Inspection and Maintenance

Hydrostatic testing on dry chemical extinguishers with stainless-steel shells is required every 5 years.
Portable extinguishers should be serviced and recharged after any discharge.
Class K extinguishers do not have a numerical rating; their efficacy is predefined by their specific use.

Fire Classes Overview

Class D fire extinguishers are marked with a yellow star and are used for combustible metals.
Class A fires involve ordinary combustibles like cloth, while Class B fires involve flammable liquids.
Class K fires pertain to cooking oils and fats, and Class C fires involve energized electrical equipment.
The weight of CO2 is approximately one-and-a-half times that of air.

Operational Use and Safety

The acronym PASS stands for Pull, Aim, Squeeze, and Sweep, guiding the operation of extinguishers.
It is vital to always maintain an exit route when approaching a fire with an extinguisher.
Using water is not recommended in certain situations where portable extinguishers are more effective.

Special Considerations

A wetting agent added to water extinguishers enhances their penetration power.
CO2 extinguishers leave no residue but are unsuitable in windy outdoor conditions.
Dry chemical agents can handle various fire classes, but the specific agent must match the fuel type for Class D fires.

Conclusion

Understanding the types, ratings, functions, and maintenance of fire extinguishers is essential for effective fire safety management.
Proper extinguisher placement, operation techniques, and awareness of fire classes can greatly enhance safety protocols.

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Description

Test your knowledge on fire extinguisher classes with these flashcards from Chapter 7. Each card presents crucial information about the usage and properties of different types of extinguishers. Perfect for anyone looking to enhance their fire safety skills.