Chapter 7 Fire extinguishers

Which class of fire is depicted in the pictograph system by a fire in a frying pan? A) K B) B C) C D) D

Which class of fire is depicted in the pictograph system by a fire in a frying pan? A) K B) B C) C D) D

A) K

Which test is required to measure the ability of an extinguisher cylinder to withstand steady internal pressure? A) Static B) Pneumatic C) Fatigue D) Hydrostatic

D) Hydrostatic

The "P" in the acronym PASS, used in reference to fire extinguisher operation, stands for: A) point. B) pick. C) pause. D) pull.

D) pull.

What is the term for the substance that puts out the fire? A) Propellant B) Extinguishing agent C) Dry charge D) Live load

B) Extinguishing agent

For an extinguishing agent to be approved for use on energized electrical equipment, it must: A) not conduct electricity. B) leave no residue. C) be non-corrosive. D) be safe for use in a closed room.

A) not conduct electricity.

A Class A fire extinguisher with a numerical rating of 2 contains _____ of water. A) 1.0 gal (3.8 L) B) 1.5 gal (5.7 L) C) 2.0 gal (7.6 L) D) 2.5 gal (9.5 L)

D) 2.5 gal (9.5 L)

What does a rating of 40 on a Class B extinguisher mean? A) BTU absorption comparable to 40 gallons (150 L) of water B) Sufficient extinguishing power for 40 ft² (4.7 m²) of burning fuel C) Sufficient extinguishing power for 40 gallons (150 L) of burning fuel D) Discharge duration of at least 40 seconds

B) Sufficient extinguishing power for 40 ft² (4.7 m²) of burning fuel

A potential problem with application of a multipurpose dry chemical agent to a Class K fire is: A) counteraction of other agents applied to the fire. B) production of toxic gas. C) spitting and splattering of fuel. D) sudden flare-up of the fire.

A) counteraction of other agents applied to the fire.

Which extinguishing method is being used when a foam blanket is placed over the surface of a burning liquid? A) Cutting off the oxygen supply B) Inhibiting the chemical chain reaction C) Diluting the fuel D) Cooling the fuel

A) Cutting off the oxygen supply

Which is a disadvantage of CO2 extinguishers? A) Electrical conductivity B) Cost C) Short discharge range D) Corrosive residue

C) Short discharge range

A Class K agent's effect on the fuel is known as: A) emulsification. B) saponification. C) dissolution. D) hydrolyzation.

B) saponification.

Which class of fire is depicted in the pictograph system by a flame and gasoline can? A) A B) B C) C D) D

B) B

All fire extinguishers are classified according to: A) the net weight of their contents. B) their relative extinguishing power. C) the classes of fire on which they are safe and effective. D) the type of extinguishing agent used.

C) the classes of fire on which they are safe and effective.

A Class C extinguisher is rated for use on: A) radioactive materials involved in flame. B) energized electrical equipment. C) combustible metals. D) cooking oil.

B) energized electrical equipment.

Which is one of the three basic components required for fire? A) An ignition source B) A catalyst C) Carbon D) Oxygen

D) Oxygen

A loaded stream extinguisher is designed to: A) prevent unnecessary water damage. B) resist freezing. C) improve fuel penetration. D) create a foam blanket

B) resist freezing.

What is the difference between dry powder and dry chemical extinguishing agents? A) There is no difference. These are two different terms for the same thing. B) A dry powder is compatible with foam; a dry chemical is not. C) A dry powder is harmful to the environment; a dry chemical is not. D) Each is rated for a different class of fire.

D) Each is rated for a different class of fire.

If a private residence has a single fire extinguisher, where should it be located? A) Garage B) Near the bedrooms C) Kitchen D) Laundry area

C) Kitchen

All portable fire extinguishers use which means for expelling their contents? A) Volume B) Vacuum C) Pressure D) Gravity

C) Pressure

For the purpose of extinguisher selection and placement, what is an example of a light hazard environment? A) Self-storage building B) Classroom C) Parking garage D) Restaurant kitchen

B) Classroom

The production and use of Halon extinguishing agents is limited because they are: A) mutagenic. B) harmful to the earth's ozone layer. C) a chemical asphyxiant. D) carcinogenic.

B) harmful to the earth's ozone layer.

Bromochlorodifluoromethane is a _________ agent. A) halon B) wet chemical C) Class D D) multipurpose dry chemical

A) halon

Which statement best summarizes when a dry chemical extinguisher should be serviced and recharged? A) After any discharge B) After a discharge resulting in loss of 10 percent of pressurization C) After a discharge resulting in loss of 20 percent of pressurization D) After a discharge resulting in loss of 30 percent of pressurization

A) After any discharge

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

A)

Gasoline

B)

Diesel fuel

C)

Cooking oil

D)

Paint thinner

C) Cooking oil

The traditional symbol for a Class D fire extinguisher is a(n): A) orange circle. B) blue square. C) yellow star. D) green triangle.

C) yellow star.

Which is a primary factor when determining hazard classification for extinguisher selection and placement? A) Permissible occupancy load B) Construction type C) Presence of a sprinkler system D) Amount of combustibles present

D) Amount of combustibles present

The weight of carbon dioxide is about ___________ times the weight of air. A) 0.5 B) 1.0 C) 1.5 D) 2.0

C) 1.5

What is the primary extinguishing mechanism of halogenated agents? A) Suppressing vapor production B) Forming a crust over the fuel C) Disrupting the molecular chain reaction D) Displacing oxygen

C) Disrupting the molecular chain reaction

Which class of fire involves energized electrical equipment? A) A B) B C) C D) D

C) C

What is an advantage of portable fire extinguishers over hose lines? A) Greater heat absorption B) Controllable rates of flow C) Longer duration D) Faster deployment

D) Faster deployment

A portable fire extinguisher is bested suited for which situation? A) Car fire B) Room and contents fire C) Fire in a wastebasket D) Vegetation fire

C) Fire in a wastebasket

To qualify as a light hazard for the purpose of extinguisher selection and placement, the majority of materials in the area must: A) be fire resistive.term-1 B) be Class A or C combustibles. C) have a flash point exceeding 150°F. D) be low combustibility.

D) be low combustibility.

Which extinguishing agent is suitable for use on a Class C fire? A) Carbon tetrachloride B) Carbon dioxide C) Dry powder D) Aqueous film-forming foam (AFFF)

B) Carbon dioxide

What residue does a CO2 fire extinguisher leave when discharged? A) Carbon B) Iron oxide C) Mineral salt D) None

D) None

For the purpose of extinguisher selection and placement, a woodworking shop is a(n) __________ hazard environment. A) light B) moderate C) ordinary D) extra

D) extra

Which is a common dry chemical extinguishing agent? A) Calcium bicarbonate B) Carbon tetrachloride C) Potassium hydrate D) Potassium chloride

D) Potassium chloride

What does it mean when a fire extinguisher has a pictograph with a red slash through it? A) Use on that class of fire would be ineffective B) Use on that class of fire could be unsafe C) The fire extinguisher has not been tested for use on that class of fire D) The fire extinguisher is rated for use on that class of fire

B) Use on that class of fire could be unsafe

How do multipurpose dry chemical agents prevent rekindling of Class A fuel? A) By forming a crust over the fuel B) By penetrating the fuel C) By attracting and holding moisture D) By interrupting the chemical chain reaction

A) By forming a crust over the fuel

What expels the extinguishing agent from a pump tank water extinguisher? A) Manual effort B) Pressure cartridge C) Compressed air D) Gravity

A) Manual effort

In general, the maximum discharge range of a CO2 extinguisher is: A) 33 ft (10 m). B) 16 ft (5 m). C) 8 ft (2.5 m). D) 5 ft (1.5 m).

C) 8 ft (2.5 m).

Class D agents work primarily by: A) penetrating the fuel. B) forming a crust over the fuel. C) suppressing vapor production. D) inhibiting the chemical chain reaction.

B) forming a crust over the fuel.

Which class of fire includes flammable and combustible liquids? A) A B) B C) C D) D

B) B

For an extinguishing agent to be rated for a particular class of fire, it must: A) be effective in portable volumes. B) be noncorrosive. C) be nontoxic. D) prevent rekindling.

D) prevent rekindling.

What is the best way to extinguish a Class C fire? A) Withdraw to a safe distance and let the fire burn itself out B) Shut off the power and treat it as a Class A or B fire C) Use a Class C extinguisher D) Shut off the fuel flow at a valve

B) Shut off the power and treat it as a Class A or B fire

Which statement is correct regarding Class D extinguishing agents? A) Application methods are similar regardless of the agent and fuel involved. B) The specific agent must be matched to the specific fuel. C) Most agents are effective on several Class D fuels. D) Some agents are also rated for other classes of fire.

B) The specific agent must be matched to the specific fuel.

For the purpose of extinguisher selection and placement, light hazard environments may contain a limited amount of combustibles of which class? A) K B) B C) C D) D

B) B

Which statement about the numerical rating of a Class K extinguisher is correct? A) There is no numerical rating for a Class K extinguisher. B) The numerical rating indicates the relative extinguishing power of the agent. C) The numerical rating indicates the relative duration of the agent. D) A numerical rating is required for commercial hood systems.

A) There is no numerical rating for a Class K extinguisher.

Dry chemical extinguishers may be used on Class C fires because they: A) are chemically inert. B) do not conduct electricity. C) are noncorrosive. D) leave no residue.

B) do not conduct electricity.

According to NFPA standards, the maximum floor area that can be protected by each extinguisher is specified according to: A) presence of built-in suppression systems. B) occupancy type. C) construction class. D) occupancy load.

B) occupancy type.

Which is the most appropriate use for a portable fire extinguisher? A) Pretreating exposures B) Diluting flammable liquids C) Situations in which the use of water is not recommended D) Overhaul

C) Situations in which the use of water is not recommended

For an area to qualify for the classification of "light hazard," most of the combustibles present must be: A) extinguishable by a portable fire extinguisher. B) arranged so that a fire is unlikely to spread. C) no more than moderately combustible. D) Class A only.

B) arranged so that a fire is unlikely to spread.

When approaching a fire with an extinguisher in hand, you should always have a(n): A) exit route. B) backup unit. C) light source. D) portable radio.

A) exit route.

Which agent is rated for use on Class A fires? A) Potassium chloride B) Potassium bicarbonate C) Ammonium phosphate D) Sodium bicarbonate

C) Ammonium phosphate

Which extinguishing agent is approved for use in a Class K system? A) Wet chemical B) Aqueous film-forming foam C) Carbon dioxide D) Dry chemical

A) Wet chemical

The hydrostatic test interval for a dry chemical extinguisher with a stainless-steel shell is every _____ years. A) 3 B) 5 C) 10 D) 12

B) 5

Which class of fire includes combustible cooking oils and fats? A) K B) A C) B D) D

A) K

Requirements for placing and mounting portable fire extinguishers are found in NFPA: A) 10. B) 170. C) 470. D) 1201.

A) 10.

Which hazard category includes automotive service or repair facilities? A) Severe B) Moderate C) Ordinary D) Extra

D) Extra

Which class of fire extinguisher includes a number in its classification? A) A B) C C) D D) K

A) A

Which part of a fire extinguisher contains the extinguishing agent? A) Cartridge B) Horn C) Chamber D) Cylinder

D) Cylinder

What is the most commonly used extinguishing agent for Class A fires? A) Water B) Ammonium phosphate C) Dry chemical D) Potassium bicarbonate

A) Water

Which class of fire is depicted in the pictograph system by a flame and an electrical plug and socket? A) K B) B C) C D) D

C) C

Which is used to pressurize a stored-pressure water extinguisher? A) Air B) Argon C) Water D) Carbon dioxide

A) Air

Which class of fire is depicted in the pictograph system by a burning trash can next to a wood fire? A) A B) B C) D D) K

A) A

What is the term for a water-soluble flammable liquid? A) Hypergolic fuel B) Polar solvent C) Solute D) Miscible liquid

B) Polar solvent

Which class of fire includes cloth? A) A B) B C) C D) D

A) A

For the purpose of fire extinguisher placement, what is the relationship between occupancy use category and hazard classification? A) They are not necessarily related B) Occupancy determines hazard C) Hazard determines occupancy D) They are different terms for the same thing

A) They are not necessarily related

Class B foam fire extinguishers are also effective on: A) Class A fires. B) Class C fires. C) Cooking oil. D) None of these is correct.

A) Class A fires.

A Class C agent must: A) be safe for use in an enclosed area. B) resist freezing. C) be compatible with foam. D) not conduct electricity.

D) not conduct electricity.

Which compound is added to a water extinguisher to improve penetration of fuel? A) Alkali metal salt B) Alcohol C) Bicarbonate D) A wetting agent

D) A wetting agent

Which statement about dry chemical agents is correct? A) Dry chemical agents are noncorrosive. B) Dry chemical agents are compatible with all types of foam. C) All dry chemical agents have a multipurpose rating. D) Dry chemical agents are not subject to freezing.

D) Dry chemical agents are not subject to freezing.

Which class of fire includes combustible metals? A) K B) A C) B D) D

D) D

Which motion best accomplishes the removal of the pin and tamper seal from a portable fire extinguisher? A) A strong pull directly outward B) Twisting motion C) Side-to-side motion D) Push, then pull

B) Twisting motion

Combustion begins when a fuel is heated to its: A) flash point. B) lower flammable limit. C) fire point. D) ignition temperature.

D) ignition temperature.

Which fire extinguishing agent is best for use on sensitive electronic equipment? A) Loaded stream B) Carbon dioxide C) Aqueous film-forming foam (AFFF) D) Ammonium phosphate

B) Carbon dioxide