Extension Cords

Normal wear on cords can loosen or expose

wires. Cords that are not 3-wire type, not

designed for hard-usage, or that have been modified, increase your risk of contacting electrical current.

• Use only equipment that is approved to meet

OSHA standards.

• Do not modify cords or use them incorrectly. 

• Use factory-assembled cord sets and only extension cords that are 3-wire type. 

• Use only cords, connection devices, and fittings

that are equipped with strain relief. 

• Remove cords from receptacles by pulling on

the plugs, not the cords. 

Equipment

Due to the dynamic, rugged nature of construction work, normal use of electrical equipment

causes wear and tear that results in insulation

breaks, short-circuits, and exposed wires. If there

is no ground-fault protection, it can cause a

ground-fault that sends current through the worker's body. 

• Use ground-fault circuit interrupters (GFCIs) on

all 120-volt, single-phase, 15- and 20-ampere

receptacles, or have an assured equipment

grounding conductor program (AEGCP). 

• Use double-insulated tools and equipment, 

distinctively marked. 

• Visually inspect all electrical equipment before

use. Remove from service any equipment with

frayed cords, missing ground prongs, cracked

tool casings, etc. 

Electrical Incidents 

If the power supply to the electrical equipment is

not grounded or the path has been broken, fault

Generators

One of the common tools utilized following the

loss of power are portable generators. Most 

generators are gasoline powered and use internal

combustion engines to produce electricity.

Carbon monoxide is a colorless and odorless gas

produced during the operation of gasoline powered generators. When inhaled, the gas reduces

your ability to utilize oxygen. Symptoms of 

carbon monoxide poisoning include headache,

nausea and tiredness that can lead to unconsciousness and ultimately prove fatal. 

• DO NOT bring a generator indoors. Be sure it is

located outdoors in a location where the

exhaust gases cannot enter a home or building.

Good ventilation is the key.

• Be sure that the main circuit breaker is OFF and

locked out prior to starting any generator. This

will prevent inadvertent energization of power

lines from back feed electrical energy from 

generators and help protect utility line workers

from possible electrocution.

• Turn off generators and let them cool prior to

refueling.

Power Lines

Overhead and buried power lines are especially

hazardous because they carry extremely high voltage. Fatal electrocution is the main risk, but burns

and falls are also hazards. 

• Look for overhead power lines and buried

power line indicators. 

• Stay at least 10 feet away from overhead power

lines and assume they are energized.

• De-energize and ground lines when working

near them. 

• Use non-conductive wood or fiberglass ladders

when working near power lines.

FactSheet

Working Safely with Electricity

Working with electricity can be dangerous. Engineers, linemen, electricians, and others work with electricity directly, including overhead lines, cable harnesses, and circuit assemblies. Office workers and salespeople work with electricity indirectly and

may also be exposed to electrical hazards. 
current may travel through a worker's body, 

causing electrical burns or death. Even when the

power system is properly grounded, electrical

equipment can instantly change from safe to hazardous because of extreme conditions and rough

treatment. 

• Visually inspect electrical equipment before use.

Take any defective equipment out of service. 

• Ground all power supply systems, electrical 

circuits, and electrical equipment. 

This is one in a series of informational fact sheets highlighting OSHA programs, policies or 

standards. It does not impose any new compliance requirements. For a comprehensive list of 

compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal

Regulations. This information will be made available to sensory impaired individuals upon request.

The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.

• Frequently inspect electrical systems to insure

that the path to ground is continuous. 

• Do not remove ground prongs from cord- and

plug-connected equipment or extension cords. 

• Use double-insulated tools and ground all

exposed metal parts of equipment. 

• Avoid standing in wet areas when using portable

electrical power tools.

U.S. Department of Labor

www.osha.gov

(800) 321-OSHA

Think Safety!

For more complete information: