Chapter 8 - Portable Fire Extinguishers
The bottom of an extinguisher should be at least _____ above the floor?
4 Inches
Class K Fire
A fire in cooking appliance that involves combustible cooking media (vegetable or animal oils and fats) (NFPA 10).
Class B Fire
A fire in flammable liquids, combustible liquids, petroleum greases, tars, oils, oil-based paints, solvents, lacquers, alcohols, and flammable gases (NFPA 10, 2007).
The icon for Class C fires is
A flame and an electrical plug and socket
Halogenated Extinguishing Agent
A liquefied gas extinguishing agent that puts out fires by chemically interrupting the combustion reaction between the fuel and oxygen.
Extinguishing Agent
A material used to stop the combustion process. Extinguishing agents may include liquids, gases, dry chemical compounds, and dry powder compounds.
Tamper Seal
A retaining device that breaks when the locking mechanism is released.
An extinguishing agent
A substance contained in a portable fire extinguisher that puts out a fire.
Handle
A trip used for holding and carrying a portable fire extinguisher.
Polar Solvent
A water-soluble flammable liquid such as alcohol, acetone, ester, and ketone.
Most fire extinguishers stop the burning by...
- Cooling the fuel below its ignition point, - Cutting off the supply of oxygen, and - interrupting the molecular chain reaction
Dry chemical extinguishing agents advantages over water:
- Effective on Class B fires - Can be used on Class C fires, bc the chemicals are nonconductive - They are not subject to freezing
Nozzle
A constricting appliance attached to the end of a fire hose or monitor to increase the water velocity and form a stream (NFPA 1965).
Locking Mechanism
A device that locks an extinguisher's trigger to prevent its accidental discharge.
Most buildings require extinguishers that are suitable for Class ____ fire but a ________ extinguisher is less expensive to get.
A, Multipurpose.
PASS
Acronym for the steps involved in operating a portable fire extinguisher: Pull pin, Aim nozzle, Squeeze trigger, Sweep across burning fuel.
Portable fire extinguishers are required in many types of occupancies as well as in...
Commercial vehicles, boats, aircraft, and various other locations.
Clean Agent
Electrically nonconducting, volatile, or gaseous fire extinguishment that does not leave a residue upon evaporation (NFPA 2001).
Ordinary (Moderate) Hazard Locations
Occupancies that contain more Class A and Class B materials than are found in light hazard locations.
Light (Low) Hazard Locations
Occupancies where the total amount of combustible materials is less than expected in an ordinary hazard location.
Extra (High) Hazard Locations
Occupancies where the total amounts of Class A combustibles and Class B flammables are greater than expected in occupancies classes as ordinary (moderate) hazards.
Examples of light hazard environments:
Offices, classrooms, churches, assembly halls, hotel rooms.
Hydrostatic Testing
Pressure testing of a fire extinguisher to verify its strength against unwanted rupture (NFPA 10).
Examples of ordinary hazard areas:
Retail stores with on-site storage areas, light manufacturing facilities, auto showrooms, parking garages, research facilities.
Fire extinguishers weighing MORE than 40lbs should be mounted...
So that the top is no more than 3ft above the floor.
Fire extinguishers weighing up to 40lbs should be mounted...
So that the top is no more than 5ft above the floor.
NFPA 10
Standard for Portable Fire Extinguishers ( lists the requirements for placing and mounting portable fire extinguishers as well as appropriate mounting heights)
Traditional lettering system
System that uses the letter for the classes of fire and the shape that correlates with the letter. not one for Class K.
Underwriters Laboratories, Inc (UL)
The U.S. organization that tests and certifies that fire extinguishers (among many other products) meet established standards. The Canadian equivalent is Underwriters Laboratories of Canada.
Areas classifications are based on...
The amount of combustibles present, including building materials, contents, decorations, and furniture.
Fire Load
The weight of combustibles in a fire area (measured in ft squared and m squared) or on a floor in buildings and structures, including either contents or building parts, or both (NFPA 914).
One advantage of portable fire extinguishers is...
Their portability
The primary disadvantage of fire extinguishers is...
They are one shot devices ( once the contents have been discharged, the device is no longer effective in fighting fires until it is recharged)
What organization developed the standards, classification, and rating system for fire extinguishers including ratings on safety and effectiveness.?
Underwriters Laboratories, Inc. (UL)
The pictographs system
Uses symbols rather than letters
Another method of applying water is through the use of...
Water-mist extinguishers
Examples of extra hazard areas:
Wood shops, service and repair for cars, kitchens that have deep fryers, flammable liquids,gases under pressure.
Class I commodities
generally non-combustible and stored on wood pallets in ordinary packaging. can be packaged in corrugated cardboard or stretch wrapped as a unit load
One notable disadvantage of water is:
it freezes at 32F
One disadvantage of dry chemical ( particularly multipurpose dry chemical) is...
it is corrosive and can damage electronic equipment.
The classification system for fire extinguishers uses both letters and numbers which represent:
letter represent the classes of fire for which extinguisher can be used, the number represents the effectiveness (only for class A and B)
Class II commodities
non-combustible commodities but packaged in wooden crates or mulit-layered cardboard cartons
Areas are classified into three risk classifications:
- Light (low) hazard - Ordinary (moderate) hazard - Extra (high) hazard
Ignition Point
The minimum temperature at which a substance will burn.
Five compounds are used as the primary dry chemical extinguishing agents:
- Sodium bicarbonate (Class B and C only) - Potassium bicarbonate (Class B and C only) - Urea-based Potassium bicarbonate ( B and C only) - Potassium chloride ( B and C) - Ammonium phosphate ( A,B,C)
Two key factors must be considered when determining which type of extinguisher should be placed in each area:
- The class of fire that is likely to occur - The potential magnitude of an incipient fire
The dry chemical extinguishing agent works in two ways:
- The dry chemicals interrupt the chemical chain reaction - The tremendous surface area of the finely ground particles allows them to absorb large quantity of heat.
Portable fire extinguishers have two primary uses:
- To extinguish incipient stage fires and - To control fires where traditional methods of fire suppression are not recommended.
The seven basic types of extinguishing agents:
- Water - Dry chemicals - CO² - Foam - Halongenated agents - Dry powder - Wet chemicals
Portable Class K wet-chemical extinguishers are available in two sizes:
1.5 gallons and 2.5 gallons
How much water does a Typical Class A fire extinguisher contain?
2.5 Gallons 2-A rating
Burning grease is generally hotter than...
212F
The discharges from halongenated-agnet extinguishers have a horizontal stream range of
9-15 ft
Class K fires are a relatively new classification, they were previously classified as...
A Class B combustible liquid fires.
The icon for Class A fires is
A burning trashcan beside a wood fire.
Rapid Oxidation
A chemical process that occurs when a fuel is combined with oxygen, resulting in the formation of ash or other waste products and the release of energy as heat and light.
Aqueous Film-Forming Foam (AFFF)
A concentrated aqueous solution of one or more hydrocarbon and/or fluorochemical surfactants that forms a foam capable or producing a vapor-suppressing aqueous film on the surface of hydrocarbon fuels (NFPA 403).
Wet-Chemical Fire Extinguisher
A fire extinguisher for use on Class K fires that contains a wet-chemical extinguishing agent.
Stored-Pressure Fire Extinguisher
A fire extinguisher in which both the extinguishing material and the expellant gas are kept in a single container, and that includes a pressure indicator or gauge (NFPA 10).
Self-Expelling Fire Extinguisher
A fire extinguisher in which the agents have sufficient vapor pressure at normal operating temperatures to expel themselves (NFPA 10).
Stored-Pressure Water-Type Fire Extinguisher
A fire extinguisher in which water or a water-based extinguishing agent is stored under pressure.
Multipurpose Dry-Chemical Fire Extinguisher
A fire extinguisher rated to fight Class A, B, and C fires. Introduced during 1960s
Cartridge/Cylinder Fire Extinguisher
A fire extinguisher that has the expellant gas in a separate container from the extinguishing agent storage container. The storage container is pressurized by a mechanical action that releases the expellant gas.
Dry-Powder Fire Extinguisher
A fire extinguisher that uses an extinguishing agent in powder or granular form. It is designed to extinguish Class D combustible-metal fires by crusting, smothering, or heat-transferring means.
Carbon Dioxide (CO2) Fire Extinguisher
A fire extinguisher that uses carbon dioxide gas as the extinguishing agent. It is rated for use on Class B and C fires.
The icon for Class K fires is
A fire in a frying pan
Class D Fire
A fire in combustible metals, such as magnesium, titanium, zirconium, sodium, lithium, and potassium (NFPA 10).
Class A Fire
A fire in ordinary combustible materials, such as wood, cloth, paper, rubber, and many plastic (NFPA 10).
Class C Fire
A fire that involves energized electrical equipment (NFPA 10).
The icon for Class B fires is
A flame and a gasoline can
Pressure Indicator
A gauge on a pressurized portable fire extinguisher that indicates the internal pressure of the expellant.
Halon 1211
A halogenated agent whose chemical name bromochlorodiflueoromethane, CBrClF2; it is a multipurpose, Class ABC-rated agent effective against flammable liquid fires (NFPA 408).
Pump Tank Fire Extinguisher
A nonpressurized, manually operated water extinguisher that is rated for use on Class A fires. Discharge pressure is provided by a hand-operated, double-acting piston pump.
Wheeled Fire Extinguisher
A portable fire extinguisher equipped with a carriage and wheels, which is intended to be transported to the fire by one person (NFPA 10).
Film-Forming Fluoroprotein (FFFP) Foam
A protein-based foam concentrate incorporating fluorinated surfactants that forms a foam capable of producing a vapor-suppressing, aqueous film on the surface of hydrocarbon fuels (NFPA 403).
Loaded-Stream Fire Extinguisher
A water-based fire extinguisher that uses an alkali metal salt as a freezing-point depressant.
What agents should be used on Class C fires?
Agents that will not conduct electricity such as dry chemicals or carbon dioxide.
Wetting-Agent Water-Type Fire Extinguisher
An extinguisher that expels water combined with a chemical or chemicals to reduce its surface tension; it is used for Class A fires.
Halogenated-Agent Fire Extinguisher
An extinguisher that uses a halogenated extinguishing agent.
Dry-Chemical Fire Extinguisher
An extinguisher that uses a mixture of finely divided solid particles to extinguish fires. The agent is usually sodium bicarbonate, potassium bicarbonate, or ammonium phosphate based, with additives being included to provide resistance to packing and moisture absorption and to promote proper flow characteristics. These extinguishers are rated for use on Class B and C fires, although some are also rated for Class A fires.
Wet-Chemical Extinguishing Agent
An extinguishing agent for Class K fires. It commonly consists of solutions of water and potassium acetate, potassium carbonate, potassium citrate, or any combination thereof.
Ammonium Phosphate
An extinguishing agent used in dry-chemical fire extinguishers that can be used on Class A, B, and C fires.
Dry-Powder Extinguishing Agent
An extinguishing agent used in putting out Class D fires. Common examples include sodium chloride and graphite-based powders.
What does the number on Class B extinguishers mean?
Based on the approximate area (measured in square feet) of burning fuel that the device is capable of extinguishing.
Cylinder
The body of the fire extinguisher where the extinguishing agent is stored.
Trigger
The button or level used to discharge the agent from a portable fire extinguisher.
Incipient Stage
The initial or beginning stage of a fire, in which it can be controlled or extinguished by portable extinguishers or small amounts of dry extinguishing agents, without the need for protective clothing or breathing apparatus (NFPA 484).
Extinguishers suitable for Class A fires are identified with:
The letter A on a solid green triangle
Extinguishers suitable for Class B fires are identified with
The letter B on a solid red square
Extinguishers suitable for Class C fires are identified with
The letter C on a solid blue circle
Extinguishers suitable for Class D fires are identified with
The letter D on a solid yellow star
Saponification
The process of converting the fatty acids in cooking oils or fats to soap or foam; the action caused by a Class K fire extinguisher.
Horn
The tapered discharge nozzle of a carbon dioxide-type fire extinguisher.
Sodium bicarbonate is often used in...
small household extinguishers
A missing icon indicates
that the extinguisher has not been rated for that class of fire.
A red slash across an icon indicates
that the extinguisher must not be used on that type of fire.
On Class A extinguishers the number reflects...
the amount of water it contains (the higher the number, the greater the extinguishing capability of the extinguisher).
A rating is only given on am extinguisher if...
the extinguisher completely extinguishes the standard test fire and prevents rekindling.
Wet-chamical extinguishers are used
to protect Class K installations, which are equipped with deep-fat dryers, cooking oils, and grills.
