|
How To Extinguish Fires
 |
Class A -
Extinguish ordinary combustibles by cooling the material below its
ignition temperature and soaking the fibers to prevent re-ignition.
Use pressurized water, foam or multi-purpose (ABC-rated) dry
chemical extinguishers. DO NOT USE carbon dioxide or ordinary (BC-rated)
dry chemical extinguishers on Class A fires. |
|
Class B - Extinguish flammable liquids, greases
or gases by removing the oxygen, preventing the vapors from reaching the
ignition source or inhibiting the chemical chain reaction.
Foam, carbon dioxide, ordinary (BC-rated) dry chemical,
multi-purpose dry chemical, and halon extinguishers may be used to fight
Class B fires. |
 |
Class C -
Extinguish energized electrical equipment by using an extinguishing agent
that is not capable of conducting electrical currents.
Carbon dioxide, ordinary (BC-rated) dry chemical, multi-purpose dry
chemical and halon* fire extinguishers may be used to fight Class C fires.
DO NOT USE water extinguishers on energized electrical equipment.
* Even though halon is widely used, EPA legislation is phasing it out
of use in favor of agents less harmful to the environment.
|
 |
Class D -
Extinguish combustible metals such as magnesium, titanium, potassium and
sodium with dry powder extinguishing agents specially designated for the
material involved.
In most cases, they absorb the heat from the material, cooling it below
its ignition temperature.
NOTE: Multipurpose (ABC-rated) chemical extinguishers leave
a residue that can harm sensitive equipment, such as computers and other
electronic equipment. Because of this, carbon dioxide or halon
extinguishers are preferred in these instances because they leave very
little residue.
ABC dry powder residue is mildly corrosive to many metals. For example,
residue left over from the use of an ABC dry powder extinguisher in the
same room with a piano can seriously corrode piano wires.
|
Back
To Safety Tips
|
