Using Portable Generators Safely
Portable generators are internal combustion engines used to generate electricity.
They are useful when temporary or remote power is needed, and are commonly
used during cleanup and recovery efforts following disasters such as hurricanes,
tornadoes, etc. This fact sheet discusses specific hazards inherent with the use
of generators and also provides helpful information to ensure that workers and
others using such equipment remain safe.
Hazards Associated with Generators:
• Shocks and electrocution from improper
use of power or accidentally energizing
other electrical systems.
• Carbon monoxide from a generator’s
• Fires from improperly refueling a generator
or inappropriately storing the fuel for a gen-
• Noise and vibration hazards.
Shock and Electrocution
The electricity created by generators has the
same hazards as normal utility-supplied elec-
tricity. It also has some additional hazards
because generator users often bypass the
safety devices (such as circuit breakers) that
are built into electrical systems. The follow-
ing precautions are provided to reduce shock
and electrocution hazards:
• Never attach a generator directly to the
electrical system of a structure (home,
office, trailer, etc.) unless a qualified electri-
cian has properly installed the generator
with a transfer switch. Attaching a genera-
tor directly to a building electrical system
without a properly installed transfer switch
can energize wiring systems for great dis-
tances. This creates a risk of electrocution
for utility workers and others in the area.
• Always plug electrical appliances directly
into the generator using the manufacturer’s
supplied cords or extension cords that are
grounded (3-pronged). Inspect the cords to
make sure they are fully intact and not
damaged, cut or abraded. Never use
frayed or damaged extension cords.
Ensure the cords are appropriately rated in
watts or amps for the intended use. Do not
use underrated cords—replace them with
appropriately rated cords that use heavier
gauge wires. Do not overload a generator;
this can lead to overheating which can cre-
ate a fire hazard.
• Use ground fault circuit interrupters
(GFCIs), especially where electrical equip-
ment is used in or around wet or damp
locations. GFCIs shut off power when an
electrical current is detected outside nor-
mal paths. GFCIs and extension cords with
built-in GFCI protection can be purchased
at hardware stores, do-it-yourself centers,
and other locations that sell electrical
equipment. Regardless of GFCI use, elec-
trical equipment used in wet and damp
locations must be listed and approved for
• Make sure a generator is properly ground-
ed and the grounding connections are
tight. Consult the manufacturer's instruc-
tions for proper grounding methods.
• Keep a generator dry; do not use it in the
rain or wet conditions. If needed, protect a
generator with a canopy. Never manipulate
a generator’s electrical components if you
are wet or standing in water.
• Do not use electrical equipment that has
been submerged in water. Equipment
must be thoroughly dried out and properly
evaluated before using. Power off and do
not use any electrical equipment that has
strange odors or begins smoking.