Ground fault circuit interrupter (GFCI) is a mechanism that stops the current flow to an electrical device within a few milliseconds of when current begins to flow where it should not, such as through a human body. Also known as a residual-current device (RCD) in some areas.

GFCI’s are intended to prevent electrocution accidents. This type of accident is common where electrical tools or equipment are being used around water or environments where there is a lot of moisture.

GFCI’s are designed to interrupt the leak of an electrical current, which can often be smaller than the current needed to operate commonly used electrical tools and devices. The GFCI device stops a harmful level of electricity from flowing through the body of a person who comes in contact with the energized part of an electrical circuit.



GFCI’s work by measuring the steady current used to operate a particular tool or device. If an inbalance occurs between the line and neutral conductors of more than about .005 amperes, then the circuit will instantly activate, open the circuit and the tool or device will be de-energized.

The use of GFCI’s is required by OSHA and NFPA (NFPA 70E 2012 Edition Section 110.4(C)) where the use of a permanently installed GFCI receptacle in a premise wiring system is not available. This situation is most common when a corded electrical tool or device is being used outdoors and a GFCI receptacle that is wired into the electrical system of a structure is not available.

The application of GFCI receptacles in residential homes has been an NFPA requirement since the early 1970’s. GFCI receptacles are commonly used in kitchens, bathrooms, and utility rooms. The GFCI receptacle usually has a red “reset” button and a black “test” button.  Not all premises provide Ground Fault Circuit Interrupter receptacles so, ITU highly recommends that a portable GFCI unit be added to your tool box and as a part of your personal protection equipment (PPE) kit.




Improper power tool storage and care will result in damage to the units electrical power cord. This causes a leak in the electrcial current which drastically increases the posibilty of electrocution.



Faulty electrical tools, devices, and extension cords injure or kill numerous workers annually. Don’t become a statistic! Portable GFCI units are relatively inexpensive, come in all shapes, sizes, and lengths and are available at most home improvement and hardware stores.

The risk of an electrical worker being injured or killed by electrocution or an electrical arc blast sometime in his or her career is already extremely high. So minimize the risk and follow the rules by utilizing a GFCI portable outlet device for every job.

References:

http://en.wikipedia.org/wiki/Residual-current_device