Town of Hamburg, NY Fire Protection Equipment

In all properties, regardless of what other extinguishing equipment is provided, there should be provision for fighting small fires. In fact, the great majority of fires are controlled by prompt attack with portable fire extinguishers. Extinguishers do not take the place of major fire fighting equipment, nor does the provision of automatic sprinklers, hand hose or fire department protection materially change the need for the hand equipment which enables small fires to be brought under control with a minimum of damage and loss of time. Portable fire extinguishers may be evaluated by checking the following factors:

(1)

Suitability of the types of extinguishers furnished to cope with the kind of fires anticipated in the property or area protected.

(2)

Sufficiency of the individual capacity and total number of extinguishers provided to cope with the severity of fires anticipated.

(3)

Location and accessibility of the extinguishers to permit prompt use.

(4)

The adequacy of maintenance facilities provided or available for proper charging, cleaning and repair of units.

(5)

The extent to which persons who may be called upon to use the extinguishers may have received instruction in their use and opportunities to practice such use.

(6)

Standard for the Installation of Portable Fire Extinguishers, NFPA No. 10; Recommended Good Practice for the Maintenance and Use of Portable Fire Extinguishers, NFPA No. 1OA; and the Model Enabling Act for the Sale or Leasing and Servicing of Portable Fire Extinguishers, NFPA No. 10L shall apply.

Suitability.

(1)

For convenience in discussing the suitability of various available extinguishing agents, fires in four general classes are designated:

(a)

Class A: fires in ordinary combustible materials, such as wood, cloth, paper, rubber and many plastics. For these, quenching and cooling effects of water, or solutions containing a large percentage of water, are of first importance.

(b)

Class B: fires in flammable liquids, gases and greases. For these, a blanketing or smothering effect is essential. Fires in some materials reactive to water but which can be smothered are in this class.

(c)

Class C: fires which involve energized electrical equipment where the electrical nonconductivity of the extinguishing media is of importance.

(d)

Class D: fires in combustible metals, such as magnesium, titanium, zironium, sodium and potassium. These are violently reactive with water and most other extinguishing agents are ineffective. Extinguishers can be said to be suitable for one class fire or another, but with some qualifications. Water solution extinguishers are of some value, for example, in fires where small amounts of oil or grease may be spilled on floors, and the types which provide a smothering action may be useful on small fires in ordinary combustibles under favorable conditions. Water solution types may be used in equipment which is electrically dead or where there is no electrical hazard.

(2)

The classifications A, B, C and D are convenient designations for common fire situations for which extinguishers are needed. The inspector should not expect to be able to fit all situations into one or another of these classes. There is the classification according to protection against freezing which is further discussed in this chapter. References to other fire classifications are noted in the following subsections:

(a)

Fires in confined spaces. In these, use of a toxic or inert gas extinguishing agent is an extra danger to an extinguisher user.

(b)

Fires in atmospheres where oxygen content is above normal, as in pressurized chambers.

(c)

Fires in materials which can be ignited by percussion to explode.

(d)

Fires in materials which produce oxygen in burning, like nitrocellulose and some oxidizing agents which are not violently reactive to water. They cannot be smothered, but require large amounts of water.

(e)

Fires in combustible gases and vapors of flammable liquids. These should often be allowed to burn to prevent explosion.

(f)

Fires in tightly packed fibers. Water with a wetting agent may be needed.

(g)

Surface fires on textiles. These should be extinguished with minimum damage to the fabric.

(h)

Fires involving combustible dusts. Violent application of an extinguishing agent could cause an explosion.

(i)

Fires in metals combustible because they are in the form of turnings or fines (not dust).

(3)

The suitability of an extinguisher is dependent on many factors which cannot be readily checked in the field by an inspector. These include proper design to provide containers strong enough to contain the pressures developed, and details which affect the life of the extinguisher and its freedom from failure even when neglected and abused. The inspector will have to be guided by acceptable evidence of suitability, such as listing and marking by Underwriters' Laboratories, Inc., Underwriters' Laboratories of Canada or Factory Mutual Research Corporation. The United States Coast Guard publishes a list of fire appliances approved for use on vessels and motor craft, and the Federal Aviation Administration, United States Department of Transportation, has specifications for certain aircraft fire extinguishers.

Protection against freezing. The operation of carbon dioxide, dry chemical, halon 1301, loaded steam and antifreeze (calcium chloride) extinguishers is not affected materially by low or freezing temperatures. Pump tanks, plain-water-type extinguishers and water pails and casks may be filled with nonfreezing solutions of calcium chloride where subject to freezing temperatures. Foam and soda-acid extinguishers depend on certain solutions, and it is not practical to put other solutions in them and to do so may make them inoperative. The inspector must see that these types are placed in locations where they will not freeze. Sometimes heated cabinets can be provided for them. He should also see that where nonfreezing solutions are used, they will afford protection at the lowest temperature likely to be experienced. See NFPA Fire Protection Handbook for the method of making and checking nonfreezing solutions of calcium chloride.

Types of fire extinguishers. This is a list of types and representative sizes of portable fire extinguishers. The water solution, two and one-half-gallon size, weighs about 40 pounds charged. The sizes selected as representative of types available in a variety of sizes are about the same. Other useful sizes are shown in manufacturers' catalogs. These include sizes much larger than those tabulated, on wheeled units. A representative size for wheeled units of soda-acid, calcium chloride, loaded stream and foam is 33 gallons' nominal capacity. There is also a wheeled unit, 45 gallons, for a water solution with a wetting agent. Representative wheeled units are 100 pounds for carbon dioxide, 150 pounds for dry chemical. The extinguishing potential of extinguishers is indicated by number and letter designations. Class A fires are those in wood, paper and the like. Class B fires are those in flammable liquids. The number preceding a B classification is based on tests on fires which can be extinguished by a trained operator with the device. Class C ratings indicate only the electrical nonconducting character of the agent. Ratings for Class D fires in combustible metals are not covered in the following table.

Type	Typical Nominal Capacity	Representative Class
Pump Tank	21/2 gallons 4 gallons 5 gallons	2-A 3-A 4-A
Water (cartridge or stored pressure types and chemically-generated expellent operated)	21/2 gallons	2-A
Antifreeze-calcium chloride solution (cartridge or stored pressure)	21/2 gallons	2-A
Antifreeze-loaded stream (cartridge or stored pressure)	21/2 gallons	3-A, 1-B
Foam	21/2 gallons	2-A, 2-B
Halon 1301 (bromotrifluoromethane)	21/2 gallons	2-A, 2-B
Carbon dioxide	20 pounds	10-B, C
Dry chemical (sodium bicarbonate base)	20 pounds	30-B, C
Dry chemical (potassium bicarbonate base)	20 pounds	60-B, C
Dry chemical (potassium chloride base)	20 pounds	60-B, C
Dry chemical (foam compatible)	20 pounds	40-B, C
Dry chemical (multipurpose, ammonium phosphate base)	20 pounds	10-A, 40-B, C

A 2-A classification is also given to the following water pail assemblies: five twelve-quart or six ten-quart water-filled pails; a cask or drum filled with 55 gallons of water with three pails; bucket tank filled with 25 to 55 gallons of water with five or six pails.