4.5.4 Controlling Electrical Hazards

– Follow the Electrical CODE
– Electrical installation
– Four proactive methods:
o electrical isolation
o equipment grounding
o circuit interruption
o safe work practices

  1. Electrical Isolation. To ensure safety, keep electricity away from workers. There are 3 ways:

– Insulate the conductors. Example: Use of rubber and plastic.
– Elevate the conductors. Example: Overhead powerlines. Never allow work within 10 feet of energized lines.
– Guard the conductors by enclosing them. Example: Receptacle covers, boxes, & conduit.
– Electric equipment operating at 50 volts or more must be guarded.

  1. Equipment Grounding. Safety is ensured by providing a separate, low resistance pathway for electricity when it does not follow normal flow (ground prong). Grounding gives the stray current somewhere to go and keeps a person from becoming part of the circuit.

Grounding does not work if:
– tool does not have a ground pin
– working in wet locations
– touching a metal object

Make sure all circuits and extension cords, non-current carrying metal parts and non-double insulated portable and semi-portable tools and equipment have proper grounding.

  1. Circuit interruption is a system that automatically shuts off the flow of electricity in the event of leakage, overload, or short circuit. They come in 2 kinds of protective devices:

– Circuit Breakers and Fuses
o devices that protects from heat build-up and meant to protect the building, equipment and tools

– Ground Fault Circuit Interrupter (GFCI)
o circuit protection device that protects a worker from shock and electrocution.

A GFCI detects ‘leakage’ of 4-6 milliamps and opens the circuit in 1/40th of a second. It works without the ground plug but not fast enough.

  1. Safe Work Practices

– User must visually inspect the equipment for defects and damage.
– If the tool or cord set is damaged, take out of service.
– Before work begins, know the location of exposed and concealed electrical circuits.
– Once found, warning signs/labels must be posted.
– Distance of the worker to the energy source should be considered first.
– Tools, materials and processes are considered to see if they could potentially shorten the safe separation distance. Examples: metal ladders, re-bar, forklift, scaffold tubes, etc.
– Must not permit work near electric circuits unless the worker is protected.
– De-energized circuits and equipment must be locked/tagged out.
– No metal ladders near electrical work.
– Only dry hands when plugging or unplugging cords/equipment.
– No raising or lowering tools by the cord.
– Unless equipment is designed for it, cannot be used in damp and wet locations.