Electrical Safety: GFCIs
The definition of a GFCI:
The GFCI is a fast-acting circuit breaker which senses small imbalances in the circuit caused by current leakage to ground, and in a fraction of a second, shuts off the electricity. GFCIs monitor the difference in current flowing into the “hot” and out to the grounded neutral conductors. The difference in current will flow back through any available path, such as the equipment grounding conductor, or through a person holding the tool if the person is in contact with a grounded object, (standing on the ground).
Why GFCIs are needed:
Extension cords tend to get twisted, punctured, etc. This may result in a conductor becoming exposed, allowing for the potential hazards of electrical shock, burns, or fire. The GFCI will sense the imbalance and immediately shut off the electricity to that tool, eliminating the potential hazard to the employee.
GFCIs also provide protection against fire, overheating, and destruction of insulation on wiring.