Usage of Fire Extinguishers.

TB 5-4200-200-10

only fire extinguishers containing bromochlorodifluoro-

Example: B:C.

methane, monobromotiuoromethane, carbon dioxide

b. The number rating of hand-portable fire extin-

or dry chemical can be used safely on Class C fires.

guishers is based on the following:

(1) Class A fires.Extinguishersrated andclas-

sified l-A,2-A, 3-A and 4-A must be capable of consis-

WARNING

tently extinguishing vertical wood panel fires having an

area of 8X8', 10X10', 12X12', and 14X14', respectfully.

Water or water-mixture type extin-

(2) Class B fires. Extinguishers a t e d a n d c l a s s

guishing agent must not be used

fied l-B, 2-B, 5-B, 10-B, etc., is an approximate indica-

under any circumstances on ener-

tion of the area in square feet of flammable liquid fire

gized electrical equipment (Class C)

(gasoline) which can be extinguisher by an average

fires. Whenever possible, electrical

operator, i.e., a 5-B rating extinguisher has an extin-

equipment and circuits should be

guishing potential of 5 square feet of liquid surface fire

deenergized before attacking Class

area.

c fire.

(3) Class C fires . No numeral rating is used, as

only the electrical nonconducting characteristics of the

CAUTION

existinguishing agent are significant, and no effort is

made to indicate the amount of electrical fire or which an

Due to its corrosive nature, dry

extinguisher is suitable

chemical is not recommended for

(4) Class D fires. No numeral rating is used as

use on computerized, electronic or

these extinguishers are rated for the amount of extin-

other equipment with extensive cir-

guishing agent needed to control a particular quantity

cuitry.

and type of combustible metal fires. This information is

detailed on the extingusher nameplate.

6. Usage of Fire Extinguishers.

Class D fires require Special fire extinguishers for spe-

a. Many fires are small at origin and maybe extin-

guished by the use of proper hand-portable fire extin-

cific combustible metal hazards; therefore, extinguish-

ers for Class D fires are not listed in the table.

guishers. It is strongly recommended that the* de-

partment be notified as soon as fire is discovered. This

d. Class B fire extinguishers in the supply system

having discontinued numeral ratings of 4-B, 6-B, 8-B,

alarm should not be delayed awaiting result of applica-

12-B, or l&B will remain in use until the extinguisher

tion of portable fire extinguishers.

becomes unserviceable and replacement is required.

b. Fire extinguishers can represent an important

6. Servicing Fire Extinguishers.

segment of any overall fire protection program. How-

a.Refillingextinguishers , especially pressurized

ever, their successful functioning depends upon the

types, will be done by personnel with knowledge of and

followin g conditions having been met:

(1) The extinguisher is p

roperly located and in

training in this function.It is not only considered hazard-

ous but id highly dangerous for personnel to service fire

working order.

.h.

extinguishers When they are unfamiliar with capacities,

(2)The extinguisher is of proper type and for a fire extinguisher

pressure limitations, and technical inspection and test

which may occur.

(3) The fire is discovered while still small enough

ing pocedures governing replacement cylinders. AR

for the extinguisher to be effective.

700-68 provides general guidance on inspection, testing,

and refilling compressed gas cylinders, which includes

(4)Thefireis discovered by a person ready,willing,

and able to use the extinguisher.

fire extinguishers Generally, refilling pressurized types

c. Class A fires can be readily extinguished by

cylinders can be done at instllation level by FireDepart

ment personnel with refillingm agents supplied through

quenching-cooling with water or a water- "xture agent.

Class B fires are more effectively extinguished by an

Iocal procurement.

agent that blankets-smothers the fire through exclu-

b.. Monobromotrifluoromethane fire extingushers,

sion of oxygen surrounding the fire area. Of those

NSN 4210-00-555-8837, will not be refilled under any

listed in the table, fire extinguishers containing

conditions, but will be serviced byd"scarding the empty

bromochlorodifluoromethane, monobromotrifluoro-

cylinder and replacing with charged cylinder requisi-

methane, carbon dioxide or drychemical are generally

tioned under NSN 4210-00-708-0031. The empty cylin-

best suited for extinguishing Class B fires. For Class C

ders are "throw away~items for which recharging is not

fires, the primary consideration in extinguishing this

considerede conomical or practical; therefore, the empty

type of fire is the selection of non-conductive extin-

cylinders will be reclassified as unserviceable.

guishing agent to prevent dangerous electrical shock

C. Dry chemical fire extinguisher, NSN 4210-00-

and possible death to user, Of these listed in the table,

775-0127, will be discarded when unserviceable.