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Questions and Answers
At what stage of fire growth are portable fire extinguishers primarily designed to function?
At what stage of fire growth are portable fire extinguishers primarily designed to function?
incipient stage
What class of fires involves ordinary combustibles such as wood, paper, cloth, and rubber?
What class of fires involves ordinary combustibles such as wood, paper, cloth, and rubber?
Class A
Which class of fires involves flammable liquids such as gasoline, oil, grease, tar, and oil-based paints?
Which class of fires involves flammable liquids such as gasoline, oil, grease, tar, and oil-based paints?
Class B
What is the standard shape used to identify a portable fire extinguisher used for flammable liquid fires?
What is the standard shape used to identify a portable fire extinguisher used for flammable liquid fires?
Which extinguishing agent is combined with alkali metal salt in a loaded-stream fire extinguisher to combat freezing of the agent?
Which extinguishing agent is combined with alkali metal salt in a loaded-stream fire extinguisher to combat freezing of the agent?
Which extinguishing agent is used for Class B and C fires and is not subject to freezing?
Which extinguishing agent is used for Class B and C fires and is not subject to freezing?
What class of foam concentrate extinguisher discharges a foam solution that floats across the surface and separates fuel from oxygen?
What class of foam concentrate extinguisher discharges a foam solution that floats across the surface and separates fuel from oxygen?
Which agent is formulated from finely ground sodium chloride and forms a solid crust over the material on fire?
Which agent is formulated from finely ground sodium chloride and forms a solid crust over the material on fire?
What is the acronym for activating a fire extinguisher to apply the extinguishing agent in four simple steps?
What is the acronym for activating a fire extinguisher to apply the extinguishing agent in four simple steps?
Which type of fire extinguisher requires hydrostatic testing every 12 years?
Which type of fire extinguisher requires hydrostatic testing every 12 years?
A Class A fire extinguisher with a numerical rating of 2 contains ______ of water.
A Class A fire extinguisher with a numerical rating of 2 contains ______ of water.
A Class B foam extinguisher is effective on all of the following fuels except one.
A Class B foam extinguisher is effective on all of the following fuels except one.
A Class C agent must:
A Class C agent must:
A Class K agent's effect on the fuel is known as:
A Class K agent's effect on the fuel is known as:
A loaded stream extinguisher is designed to:
A loaded stream extinguisher is designed to:
A portable fire extinguisher is best suited for which situation?
A portable fire extinguisher is best suited for which situation?
A potential problem with the application of a multipurpose dry chemical agent to a Class K fire is:
A potential problem with the application of a multipurpose dry chemical agent to a Class K fire is:
According to NFPA standards, the maximum floor area that can be protected by each extinguisher is specified according to:
According to NFPA standards, the maximum floor area that can be protected by each extinguisher is specified according to:
All fire extinguishers are classified according to:
All fire extinguishers are classified according to:
All portable fire extinguishers use which means for expelling their contents?
All portable fire extinguishers use which means for expelling their contents?
Bromochlorodifluoromethane is a _________ agent.
Bromochlorodifluoromethane is a _________ agent.
Class B foam fire extinguishers are also effective on:
Class B foam fire extinguishers are also effective on:
Class D agents work primarily by:
Class D agents work primarily by:
For an area to qualify for the classification of 'light hazard,' most of the combustibles present must be:
For an area to qualify for the classification of 'light hazard,' most of the combustibles present must be:
For an extinguishing agent to be rated for a particular class of fire, it must:
For an extinguishing agent to be rated for a particular class of fire, it must:
For the purpose of fire extinguisher placement, what is the relationship between occupancy use category and hazard classification?
For the purpose of fire extinguisher placement, what is the relationship between occupancy use category and hazard classification?
How do multipurpose dry chemical agents prevent rekindling of Class A fuel?
How do multipurpose dry chemical agents prevent rekindling of Class A fuel?
In general, the maximum discharge range of a CO2 extinguisher is:
In general, the maximum discharge range of a CO2 extinguisher is:
Requirements for placing and mounting portable fire extinguishers are found in NFPA:
Requirements for placing and mounting portable fire extinguishers are found in NFPA:
The 'P' in the acronym PASS, used in reference to fire extinguisher operation, stands for:
The 'P' in the acronym PASS, used in reference to fire extinguisher operation, stands for:
The hydrostatic test interval for a dry chemical extinguisher with a stainless-steel shell is every _____ years.
The hydrostatic test interval for a dry chemical extinguisher with a stainless-steel shell is every _____ years.
The production and use of Halon extinguishing agents is limited because they are:
The production and use of Halon extinguishing agents is limited because they are:
The weight of carbon dioxide is about ___________ times the weight of air.
The weight of carbon dioxide is about ___________ times the weight of air.
What does a rating of 40 on a Class B extinguisher mean?
What does a rating of 40 on a Class B extinguisher mean?
What expels the extinguishing agent from a pump tank water extinguisher?
What expels the extinguishing agent from a pump tank water extinguisher?
What is the best way to extinguish a Class C fire?
What is the best way to extinguish a Class C fire?
What is the difference between dry powder and dry chemical extinguishing agents?
What is the difference between dry powder and dry chemical extinguishing agents?
What is the primary extinguishing mechanism of halogenated agents?
What is the primary extinguishing mechanism of halogenated agents?
What is the term for a water-soluble flammable liquid?
What is the term for a water-soluble flammable liquid?
What is the term for the substance that puts out the fire?
What is the term for the substance that puts out the fire?
What residue does a CO2 fire extinguisher leave when discharged?
What residue does a CO2 fire extinguisher leave when discharged?
When approaching a fire with an extinguisher in hand, you should always have a(n):
When approaching a fire with an extinguisher in hand, you should always have a(n):
Which agent is rated for use on Class A fires?
Which agent is rated for use on Class A fires?
Which class of fire includes combustible cooking oils and fats?
Which class of fire includes combustible cooking oils and fats?
Which class of fire includes combustible metals?
Which class of fire includes combustible metals?
Which class of fire includes flammable and combustible liquids?
Which class of fire includes flammable and combustible liquids?
Which class of fire is depicted in the pictograph system by a burning trash can next to a wood fire?
Which class of fire is depicted in the pictograph system by a burning trash can next to a wood fire?
Which class of fire is depicted in the pictograph system by a fire in a frying pan?
Which class of fire is depicted in the pictograph system by a fire in a frying pan?
Which class of fire is depicted in the pictograph system by a flame and an electrical plug and socket?
Which class of fire is depicted in the pictograph system by a flame and an electrical plug and socket?
Which class of fire is depicted in the pictograph system by a flame and a gasoline can?
Which class of fire is depicted in the pictograph system by a flame and a gasoline can?
Which compound is added to a water extinguisher to improve penetration of fuel?
Which compound is added to a water extinguisher to improve penetration of fuel?
Which extinguishing agent is approved for use in a Class K system?
Which extinguishing agent is approved for use in a Class K system?
Which extinguishing method is being used when a foam blanket is placed over the surface of a burning liquid?
Which extinguishing method is being used when a foam blanket is placed over the surface of a burning liquid?
Which fire extinguishing agent is best for use on sensitive electronic equipment?
Which fire extinguishing agent is best for use on sensitive electronic equipment?
Which hazard category includes automotive service or repair facilities?
Which hazard category includes automotive service or repair facilities?
Which is a common dry chemical extinguishing agent?
Which is a common dry chemical extinguishing agent?
Which is a disadvantage of CO2 extinguishers?
Which is a disadvantage of CO2 extinguishers?
Which is used to pressurize a stored-pressure water extinguisher?
Which is used to pressurize a stored-pressure water extinguisher?
Which motion best accomplishes the removal of the pin and tamper seal from a portable fire extinguisher?
Which motion best accomplishes the removal of the pin and tamper seal from a portable fire extinguisher?
Which part of a fire extinguisher contains the extinguishing agent?
Which part of a fire extinguisher contains the extinguishing agent?
Which statement about dry chemical agents is correct?
Which statement about dry chemical agents is correct?
Which statement about the numerical rating of a Class K extinguisher is correct?
Which statement about the numerical rating of a Class K extinguisher is correct?
Which statement best summarizes when a dry chemical extinguisher should be serviced and recharged?
Which statement best summarizes when a dry chemical extinguisher should be serviced and recharged?
Which statement is correct regarding Class D extinguishing agents?
Which statement is correct regarding Class D extinguishing agents?
Which test is required to measure the ability of an extinguisher cylinder to withstand steady internal pressure?
Which test is required to measure the ability of an extinguisher cylinder to withstand steady internal pressure?
Study Notes
Fire Extinguisher Basics
- Portable fire extinguishers are primarily designed to function during the incipient stage of fire growth.
- All extinguishers are classified according to the types of fires they can effectively combat.
Fire Classes
- Class A fires involve ordinary combustibles, including wood, paper, cloth, and rubber.
- Class B fires involve flammable liquids such as gasoline, oil, grease, tar, and oil-based paints.
- Class C fires consist of energized electrical equipment, which must not conduct electricity.
- Class K fires include combustible cooking oils and fats, while Class D fires involve combustible metals.
Extinguishing Agents
- Common Class A extinguishing agents include water and ammonium phosphate.
- Dry chemical agents are effective for Class B and C fires and typically do not freeze.
- Halogenated agents, such as bromochlorodifluoromethane (halon), disrupt molecular chain reactions to extinguish fires.
- CO2 extinguishers leave no residue upon discharge and are suitable for sensitive electronic equipment.
- Wet chemical agents are specifically approved for Class K systems.
Fire Extinguisher Usage
- The acronym PASS stands for Pull, Aim, Squeeze, and Sweep, representing the steps for operating a fire extinguisher.
- A loaded stream extinguisher is designed to resist freezing, typically using water as an extinguishing agent.
- To combat cooking oil fires, using the proper Class K agents is crucial as cooking oil is ineffective against Class B foam extinguishers.
Extinguisher Maintenance
- Halogenated agent extinguishers require hydrostatic testing every 12 years, while dry chemical extinguishers with stainless-steel shells need testing every 5 years.
- Extinguishers should be serviced and recharged after any discharge to ensure readiness.
- The maximum discharge range of a CO2 extinguisher is approximately 8 feet (2.5 m).
Important Considerations
- Situations best suited for portable extinguishers include small fires such as those in wastebaskets.
- The effectiveness of a Class A extinguisher with a numerical rating of 2 corresponds to 2.5 gallons (9.5 L) of water.
- Each Class B extinguisher’s rating reflects its extinguishing power over a specified area, e.g., a rating of 40 means it can handle 40 ft² (4.7 m²) of burning fuel.
Fire Safety Standards
- According to NFPA standards, extinguisher placement and the maximum floor area protected are dependent on occupancy type.
- The placement of extinguishers does not necessarily correlate with the occupancy use category.
- Class D extinguishing agents must be specifically matched to the fuel type of the fire for effective suppression.
Other Relevant Facts
- Dry powder agents form a solid crust over burning materials, effectively suffocating the fire.
- The weight of carbon dioxide is about 1.5 times that of air, which helps in suppression by displacing oxygen.
- A water-soluble flammable liquid is referred to as a polar solvent, which poses particular hazards.
Summary of Extinguisher Components
- The cylinder of a fire extinguisher contains the extinguishing agent, while air is used to pressurize a stored-pressure water extinguisher.
- The extinguishing action provided by foam blankets involves cutting off the oxygen supply from the burning liquid's surface.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Test your knowledge with these flashcards on fire fighting concepts from Chapter 7. Focus on different classes of fires, their characteristics, and effective extinguishing methods. Ideal for students and professionals looking to reinforce their understanding of fire safety.
