Chapter 1 Introduction to a Typical PC 29
Fire Safety
The possibility of fire is always a threat
in a computer laboratory as well as on the
job or in your home. You should have a basic
understanding of fire extinguisher types and how
to use them in the event of a fire. Pay particular
attention to the information related to electrical
fires. Always follow your teacher’s instructions
concerning fire safety procedures and fire safety
in the classroom and lab.
Fire extinguishers are divided into five classes
and assigned letters to represent the classification,
Figure 1-41.
The following table lists the classes and a
description of each.
Class Description
Class A Ordinary materials such as paper, wood,
cardboard, most plastics, and
similar materials.
Class B Flammable liquids such as gasoline,
kerosene, oil, and common combustible
solvents.
Class C Energized electrical equipment, appli-
ances, fuse boxes, electrical power tools,
wiring, and other electrical devices.
Class D Combustible metals such as magnesium,
sodium, potassium, and titanium.
Class K Kitchen fi res caused by cooking grease
and oils.
Some fire extinguishers are designated with
a combination of letters, which means they are
suitable for each classification indicated by letter.
For example, a fire extinguisher with the letters A,
B, and C would be suitable for a Class A, B, or C
fire.
Obviously, a computer lab should be equipped
with a Class C fire extinguisher or one that is
designated with a combination of letters, as long
as the letter C is clearly marked.
Water extinguishers are only appropriate for
Class A fires and should never be used on a Class
B, C, D, or K fire. Class A uses water or a liquid
that reacts violently with Class B, C, D, and K fires
and could cause the fire to spread rather than
extinguish.
The CompTIA A+ exams often have at least
one question related to fire safety.
A+ Note
The handy acronym PASS is used to
remember the proper procedure for using a
fire extinguisher. This acronym was developed
to match the recommended procedures by the
National Fire Protection Agency (NFPA) for fire
extinguisher use. While standing approximately
six to eight feet from the fire, follow the procedure
as outlined.
P
= Pull the pin.
A
= Aim at the base of the fire.
S
= Squeeze the handles together
slowly to discharge the fire
extinguisher.
S
= Sweep the nozzle from side to
side, moving carefully toward
the fire while keeping the
discharge aimed at the base of
the fire.
Gauge
Handles
Pin
Goodheart-Willcox Publisher
Figure 1-41. Always know the location of the nearest fire
extinguisher and how to properly use one.