| ampacity
|
| maximum amount
of current a wire can carry safely without overheating. |
| amperage |
| strength of
an electrical current, measured in ampress |
| ampere
(amp) |
| unit used
to measure current |
| arc-blast |
| explosive
release of molten material from equipment caused by high-amperage
arcs |
| arcing |
| luminous electrical
discharge (bright, electrical sparking) through the air that occurs
when high voltages exist across a gap between conductors |
| AWG |
| American
Wire Gauge- measure of wire size |
| bonding |
| joining electrical
parts to assure a conductive path |
| bonding
jumper |
| conductor
used to connect parts to be bonded |
| circuit |
| complete path
for the flow of current |
| circuit
breaker |
| overcurrent
protection device that automatically shuts off the current in a
circuit if an overload occurs |
| conductor |
| material in
which an electrical current moves easily |
| CPR |
| cardiopulmonary
resuscitation—emergency procedure that involves giving artificial
breathing and heart massage to someone who is not breathing or does
not have a pulse (requires special training) |
| current |
| movement of
electrical energy |
| de-energize |
| shutting off
the energy sources to circuits and equipment and depleting any stored
energy |
| double-insulated |
| equipment
with two insulation barriers and no exposed metal parts |
| energized
(live, "hot") |
| similar terms
meaning that a voltage is present that can cause a current, so there
is a possibility of getting shocked |
| fault current |
| any current
that is not in its intended path |
| fixed wiring |
| permanent
wiring installed in homes and other buildings |
| flexible
wiring |
| cables with
insulated and stranded wire that bends easily |
| fuse |
| overcurrent
protection device that has an internal part that melts and shuts
off the current in a circuit if there is an overload |
| GFCI |
| ground
fault circuit interrupter—a device that
detects current leakage from a circuit to ground and shuts the current
off |
| ground |
| physical electrical
connection to the earth |
| ground
fault |
| loss of current
from a circuit to a ground connection |
| ground
potential |
| voltage a
grounded part should have; 0 volts relative to ground |
| guarding |
| covering or
barrier that separates you from live electrical parts |
| insulation |
| material that
does not conduct electricity easily |
| leakage
current |
| current that
does not return through the intended path, but instead "leaks"
to ground |
| lock-out |
| applying a
physical lock to the energy sources of circuits and equipment after
they have been shut off and de-energized |
| milliampere
(milliamp or mA) |
| 1/1,000 of
an ampere |
| NEC |
| National
Electrical Code—comprehensive listing of practices
to protect workers and equipment from electrical hazards such as
fire and electrocution |
| neutral |
| at ground
potential (0 volts) because of a connection to ground |
| ohm |
| unit of measurement
for electrical resistance |
| OSHA |
| Occupational
Safety and Health Administration—Federal
agency in the U.S. Department of Labor that establishes and enforces
work-place safety and health regulations |
| overcurrent
protection device |
| device that
prevents too much current in a circuit |
| overload |
| too much current
in a circuit |
| power |
| amount of
energy used each second, measured in watts |
| PPE |
| personal protective
equipment (eye protection, hard hat, special clothing, etc.) |
| qualified
person |
| someone who
has received mandated training on the hazards and on the construction
and operation of equipment involved in a task |
| resistance |
| material’s
ability to decrease or stop electrical current |
| risk |
| chance that
injury or death will occur |
| shocking
current |
| electrical
current that passes through a part of the body |
| short |
| low-resistance
path between a live wire and the ground, or between wires at different
voltages (called a fault if the current is unintended) |
| tag-out |
| applying a
tag that alerts workers that circuits and equipment have been locked
out |
| trip |
| automatic
opening (turning off) of a circuit by a GFCI or circuit breaker |
| voltage |
| measure of
electrical force |
| wire gauge |
| wire size
or diameter (technically, the cross-sectional area) |
| |
| Endnotes |
| 1. Castillo
DN [1995]. NIOSH alert: preventing death and injuries of adolescent
workers. Cincinnati, OH: U.S. Department of Health and Human Services,
Public Health Service, Centers for Disease Control and Prevention,
National Institute for Occupational Safety and Health, DHHS (NIOSH)
Publication No. 95-125. |
| 2. Lee RL
[1973]. Electrical safety in industrial plants. Am Soc Safety Eng
J 18(9):36-42. |
| 3. DOL [1997].
Controlling electrical hazards. Washington, DC: U.S. Department
of Labor, Occupational Safety and Health Administration. |
