Fire safety

Scope

OSHA regulations address requirements for fire brigades, and all portable and fixed fire suppression equipment, fire detection systems, and fire or employee alarm systems.

Regulatory citations

OSHA regulates several aspects of fire prevention and response. Fire safety is addressed in specific standards for recordkeeping, the general industry, shipyard employment, marine terminals, longshoring, gear certification, and the construction industry.

Emergency planning, fire prevention plans and evacuation that would need to be done in the event of a serious fire are addressed in the OSHA standard, 1910.38. In addition, the provision of fire extinguishers and other protection is addressed in 1910.157.

See 1910 Subparts E and L; and 1926 Subparts C and F.

Key definitions

The National Fire Protection Association (NFPA) has classified five general types of fires, based on the combustible materials involved and the kind of extinguisher needed to put them out. The five fire classifications are A, B, C, D, and K. Each classification has special markings, and A through D have special symbols and color identification. The five are as follows:

• Class A. This type of fire is the most common. The combustible materials are wood, cloth, paper, rubber and plastics. The common extinguisher agent is water, but dry chemicals are also effective. Carbon dioxide extinguishers and those using sodium or potassium bicarbonate chemicals are not to be used on this type of fire.
• Class B. Flammable liquids, gases and greases create class B fires. The extinguishers to use are foam, carbon dioxide and dry chemical. Also, water fog and vaporizing liquid extinguishers can be used.
• Class C. Class C fires are electrical fires and a nonconducting agent must be used. Carbon dioxide and dry chemical extinguishers are to be used. Never use foam or water-type extinguishers on these fires.
• Class D. Combustible metals, such as magnesium, titanium, zirconium and sodium fires are class D. These fires require specialized techniques to extinguish. None of the common extinguishers should be used since they can increase the intensity of the fire by adding an additional chemical reaction.
• Class K.Class K fires involve cooking appliances and combustible cooking media (vegetable or animal oils and fats). Wet chemical-based extinguishers are recommended.

There are only two dry chemical extinguishers that can be used on A, B, and C fires, and those are multi-purpose ABC extinguishers, either stored pressure or cartridge operated. Multi-purpose extinguishers (ABC) will handle all A, B, and C fires.All fire extinguishers are labeled with either ABC, or A, or B, or C.

It is important to know what type of fire is in progress. If you use a fire extinguisher, be sure to use one only on fires for which that fire extinguisher is designed. Using the wrong agent on a fire may increase the intensity of the fire. Check the label on the fire extinguisher; it should list the fire class(es) it is meant to put out.

Summary of requirements

In order to burn and continue to burn, a fire requires the right combination of four basic elements: these are fuel, oxygen, ignition, and an uncontrolled chemical reaction (combustion). Without one of these elements in the proper amount, the fire will not start, or if it has already started, will go out. Fire can be represented by a simple equation:

Chemical fires. Many of the thousands of chemicals in use in the workplace are both highly toxic and highly volatile. Extreme caution must be used to prevent and fight fires resulting from chemical spills and accidents. Chemicals can cause serious injuries through physical (fire or explosion) or health (burns or poisons) hazards. Chemicals are classified by the inherent properties that make them hazardous.

• Flammable. These chemicals catch fire very easily; hazards include property damage, burns and injuries that result when toxic and corrosive compounds are released into the air.
• Reactive. A reactive material is one that can undergo a chemical reaction under certain conditions; reactive substances can burn, explode, or release toxic vapor if exposed to other chemicals, air or water.
• Explosive. An explosive is a substance which undergoes a very rapid chemical change producing large amounts of gas and heat; explosions can also occur as a result of reactions between chemicals not ordinarily considered explosive.

Heating and electrical systems.

• Keep extension cords and electrical wiring out of aisles. They are likely to get walked on and damaged creating a fire hazard. Check cords for fraying and damaged plugs. Use cords rated for their intended use and constructed with heavy gauge wire;
• Secure covers on all junction, switch, outlet, and panel board boxes;
• Use automatic circuit breakers and over-current relays when possible to guard against electrical overload;
• Keep motors free of dust, oil, or fibers;
• Clean filters on a regular schedule; and
• Maintain electrical equipment regularly.

• Control static electricity by bonding and grounding equipment or through the use of special flooring designed to eliminate static electricity.

Hot work. When performing hot work follow the hot work permit, clear the welding area of combustibles, and have someone available to operate a fire extinguisher during the job and for at least 30 minutes after the job is completed.

Flammable liquids.

• Store flammable liquids in trash-free areas in approved safety containers with vapor-tight, self-closing covers. Inspect safety cans for dents or cracks. Flame arresters or filters should be in place on safety cans;
• Use flammable liquids in adequately ventilated areas;
• Post warning signs when highly volatile and dangerous liquids are in use;
• Do not smoke where flammable liquids are used;
• Do not create open flames or sparks where flammable liquids are used; and
• Keep sparking tools away from explosive/flammable materials areas.

• Dispose of trash and packing material in metal containers with tight-fitting lids;
• Place extra storage and equipment in proper areas, not in aisles or near fire exits. Dispose of or store extra boxes and paper away from ignition sources;
• Do not stack materials so high that they interfere with automatic sprinkler systems;
• Clean up chemical spills and oil immediately; and
• Look around the area for ways to lessen the pile up of waste and storage.