Working near an electrical hazard is dangerous and can be fatal. Any work on or near energized equipment must be done only when measures are in place to provide protection from electric shock and burn. With adequate safety measures in place, every electrical injury and fatality can be prevented.
Electrical hazards
An electrical hazard can be defined as
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a dangerous condition where a worker could make electrical contact with energized equipment or a conductor, and from which the person may sustain an injury from shock; and/or,
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there is potential for the worker to receive an arc flash burn, thermal burn, or blast injury.
An electric hazard is considered to be removed when protective measures are put in place at the source (remove hazard or deenergize), or along the path (place electrical insulation/barrier between the worker and the electrical hazard). Where PPE is relied upon for worker protection, an electrical hazard is considered to remain and it is still necessary to address safety requirements for other workers in the area.
Electrical Injuries
There are basically two ways to be injured by electricity. One is by electric shock and the other is by arc flash.
Electric shock is the passing of electric current through the body. Electrical contact can cause involuntary physical movements. The electrical current may
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prevent you from releasing your grip from a live conductor
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throw you into contact with a higher voltage conductor
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cause you to lose your balance and fall
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cause severe internal and external burns
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kill you.
A household 125-volt circuit can deliver 15 amps. Current as low as 30/1000 of 1 amp (30 mA) can cause breathing to stop. A 15-Amp circuit contains many times the current needed to cause death.
An arc flash is a release of energy caused by an electric arc. The flash causes an explosive expansion of air and metal. The blast produces
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a dangerous pressure wave
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a dangerous sound wave
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shrapnel
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extreme heat
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extreme light.
These dangers can result in blast injuries, lung injuries, ruptured eardrums, shrapnel wounds, severe burns, and blindness. Arc flash injuries can also result in death.
Legislation and Guidelines
The law requires safe work practices. Under the Occupational Health and Safety Act and Regulations for Construction Projects, employers, supervisors, and workers each have legal responsibilities to ensure that work is being carried out in a safe manner. There are also restrictions in the Construction Regulation (O. Reg. 213/91, Section 182) on who is permitted to work on electrical equipment.
Guidelines for working on or near electrical equipment and conductors are found in several documents:
Training
Classroom-based Courses
Online Courses
Products
Safety Talks
Construction Health and Safety Manual
Documents and Articles
Sample Policies and Procedures
The health and safety policy & program section of our website contains information and sample documents to help you create or update your policy and program. Documents relating to electrical hazards are below.