Chapter 9 - Portable Fire Extinguishers Flashcards
Which NFPA standard provides information on the selection and use of fire extinguishers ?
NFPA 10
p 212
Fire extinguishers are labeled according to the ______________ of ______ that they will extinguish.
Classifications of fire
p 213
NFPA 10 recognizes two different methods of extinguisher recognition: ?
pictorial system and letter-symbol system
p 213
The __________ ____________ system is the most widely used fire extinguisher identification system.
pictorial labeling
p 213
It is important to note that the ________-__________ method of fire extinguisher identification is rapidly losing its usefulness in favor of the internationally recognized pictograph system.
letter-symbol
p 214
Portable fire extinguisher ratings:
The rating system is based upon the extinguishment of test fires in accordance with _______.
UL 711, Standard for Rating and Fire Testing of Fire Extinguishers
p 214
Fire extinguisher ratings:
The ratings consist of both a _________ and ________ designation for extinguishers intended to combat Class A and Class B fires.
numeric and letter
p 214
Extinguishers classified for Class ____ fires receive only a letter rating because fires involving energized electrical equipment are fueled by materials that are typically Class A and Class B in composition.
C
p 214
A 5 to 6 pound dry chemical extinguisher is rated at _____ or _____ depending on its chemical mixture.
2A or 3A
p 214
The smallest B:C type extinguishers have a _____ to _____ rating.
5B to 10B
p 214
All other things being equal, a 4A or 40B rated extinguishers should be ________ as effective as a 2A or 20B extinguisher.
twice
p 214
Class ____ ratings are never assigned to any type of multipurpose extinguisher.
D
p 215
Extinguishers classified for Class ____ fires receive only a letter rating because fires involving energized electrical equipment are fueled by materials that are typically Class A and Class B in composition.
C
p 214
A 5 to 6 pound dry chemical extinguisher is rated at _____ or _____ depending on its chemical mixture.
2A or 3A
p 214
The smallest B:C type extinguishers have a _____ to _____ rating.
5B to 10B
p 214
All other things being equal, a 4A or 40B rated extinguishers should be ________ as effective as a 2A or 20B extinguisher.
twice
p 214
Class ____ ratings are never assigned to any type of multipurpose extinguisher.
D
p 215
All extinguishers are tested in order to obtain a ____ rating.
UL
p 215
Discharge volume capability:
- Any portable fire extinguisher that uses dry chemical or dry powder as an extinguishing agent must be able to discharge _____ percent of its contents.
- Any portable fire extinguisher that uses agents other than dry chemical or dry powder (halon, carbon dioxide, water, etc.) must be able to discharge _____ percent of its contents.
80 / 95
p 215
Discharge duration:
- A portable extinguisher that uses water stored under pressure as an extinguishing agent must have a minimum of a _____ to _____ second discharge time.
45 to 60
p 215
Discharge duration:
- A minimum effective discharge time is required for any extinguisher for which a Class ____ rating is desired.
B
p 215
Discharge duration:
- Dry chemical extinguishers 10 pounds and larger must have a discharge rate of ___ __________ per second.
1 pound
p 215
Discharge range:
- Extinguishers that use water stored under pressure must have a minimum effective discharge of _____ feet for a _____ second period.
- Dry chemical and dry powder extinguishers must have a minimum horizontal discharge range of _____ feet.
30 / 40
10
p 215
- A testing method that uses water under pressure to check the integrity of pressure vessels.
Hydrostatic test
p 215
Hydrostatic test consist of pressurizing the components to five times their rated capacity for a period of not less than ____ seconds.
5
p 215
Class A portable fire extinguishers are rated from ____ through _____.
1A / 40A
p 216
Class A ratings test:
The ratings are based on _____ different test fires using various sizes of fuel cribs. These tests fires include a ______-_____ test and a ______-________ test.
two / wood-crib / wood-panel
p 216
Extinguishers suitable for use on Class B fires are classified with a numerical rating ranging from _____ to _______.
1B to 640B
p 216
Class B rating tests:
The number is an indication of the approximate ________ ______ area of fire involving a ____ inch layer of flammable liquid that can be extinguished by a novice or inexperienced operator.
square foot / 2
p 216
Class B rating tests:
The rating is based on the principle that an expert extinguisher operator such as a laboratory technician can extinguish ____ and ____-______ times more fire than a novice.
two and one-half times
p 216
Class B ratings test:
For example, a novice extinguisher operator using a 60B rated extinguisher can be expected to extinguish a flammable liquid fire involving a ______ area and an expert a ______ area.
60 ft^2 / 150 ft^2
p 216
Extinguishers with a rating of ______ or greater are considered suitable for outdoor fires.
20B
p 216
A _______ ____ rating is not assigned a numerical designation because the rating signifies only that the extinguishing agent is electrically nonconductive.
Class C
p 216
Class D fire extinguishers are not given ___________ ratings.
numerical
p 217
Class D ratings test:
These types of extinguishers are generally tested against fires involving specific combustible metals including ____________, _________, and ______________.
magnesium, sodium, and potassium
p 217
Class D rating test:
- Four magnesium fire tests
- _______ fire test
- ________-_________ fire test
- ________ fire test
- ________ fire test
- Area
- Pallet-transfer
- Premix
- Casting
p 217
Class D ratings tests:
For sodium and potassium ratings, there are two standard procedures for testing: ?
Both test are conducted when the metals are in a _______ state.
spill-fire test and pan-fire test / liquid
p 217
Class K fire extinguishers are rated for their ability to extinguish fire in _____________ ____________ environments. The fuel used must be new vegetable shorting or oil with an antifoaming agent and an autoignition temperature of ______ *F or higher. Test are performed on a commercial ______ _____ _______.
commercial cooking / 685 / deep fat fryer
p 217
Extinguishing agents:
Water
A 5-gallon water extinguisher weighs in excess of ____ pounds and is the maximum size that is considered truly __________.
42 / portable
p 217
Since __________ water has most of the minerals removed, its use is acceptable on Class C fires.
distilled
p 218
Extinguishing agents:
This agent produces both air foam and a floating film on the surface of a liquid fuel and is suitable for both Class A and Class B fires ?
Aqueous film forming foam ( AFFF)
p 218
Extinguishing agents:
This foam is usually diluted in a solution of water and 3 or 6 percent foam and is effective on Class A and Class B fires ?
Film forming fluoroprotein (FFFP)
p 218
Extinguishing agents:
This agent is a colorless, non combustible gas that is heavier than air. It extinguishes fire primarily through a smothering action by establishing a gaseous blanket between the fuel and the surrounding air ?
Carbon dioxide
p 218
Extinguishing agents:
__________ and other _______________ agents contain atoms from one of the halogen series of chemical elements: fluorine, chlorine, bromine, and iodine. This agent is principally effective on Class B and Class C fires.
Halons / halogenated agents
p 218
Extinguishing agents:
In physical form, ______ __________ agents are very small solid powdery particles.
dry chemical
p 219
Extinguishing agents:
This agent is a form of baking soda and was the first commercially produced dry chemical agent ?
Sodium bicarbonate
p 219
Extinguishing agents:
This agent also known as Purple K, is deemed twice as effective as sodium bicarbonate in fire extinguishment ?
Potassium bicarbonate
p 220
Extinguishing agents:
Monoammonium phosphate is an effective and popular agent for use on Class ___, Class ____, and Class ____ fires.
Class A, Class B, and Class C
p 220
Extinguishing agents:
______ __________ extinguishing agents are those used for extinguishing Class D fires and are not to be confused with dry chemicals.
Dry powder
p 220