The ground-fault circuit interrupter, or GFCI, is a fast-acting circuit breaker designed to shut off electric power in the event of a ground-fault within as little as 1/40 of a second. Electrical hazards are an area of major safety concern in most industries and account for a large number of injuries and fatalities. Extension cords and ground fault circuit interrupters (GFCIs) can be found on any construction site, shop, and jobsite as well as office buildings, warehouses and manufacturing plants. Remembering a few safety tips can help prevent serious injuries from happening.
A ground fault circuit interrupter can help prevent electrocution. If a person’s body starts to receive a shock, the GFCI senses this and cuts off the power before he/she can get injured. A “ground fault” is a conducting connection (whether intentional or accidental) between any electric conductor and any conducting material that is grounded or that may become grounded. Because of this potential for shock, GFCI protection is used to protect human life. It works by comparing the amount of current going to and returning from equipment along the circuit conductors.
It is recommended that GFCIs be installed in areas where appliances and power tools are used in close proximity to water. Tap water or wet objects are able to conduct electricity very easily and can connect your body to a ground potential, thus increasing your chances of receiving a shock from a ground fault. Appliances that have built-in GFCI protection, as now required for hair dryers, may not need additional GFCI protection, but there are still many appliances not equipped with GFCI protection. It takes only 5 mA (0.005 A) of current leakage from the hot wire to the ground to cause a GFCI to trip.
- From a small kitchen lobby in an office building to an industrial food plant, when using electrical equipment or extension cords near a water source they should be plugged into an outlet that is GFCI protected.
- When operating machine pumps, welding equipment, or other high energy producing equipment or tools, an industrial GFCI should be used.
- Always test GFCIs before use by using the test and reset buttons. If found defective do not use.
- Inspect all tools and equipment before use, if the ground pin is missing do not use it.