Using GFCI (Ground Fault Circuit Interrrupter) outlets can greatly reduce electrocution hazards when working with power tools.
GFCI: A Great Safety Tool
The widespread use
of portable tools on construction sites, particularly when used with flexible
cords, creates the potential for electric shock and even death. This is
because cords, cord connectors, receptacles and cord and plug-connected
equipment are more vulnerable to damage by activities on the job or just
aging, potentially exposing the electric wires. A cord assembly with improperly
connected terminals is also a frequent hazard. Wet conditions, including
wet clothing, high humidity, standing water, or perspiration increase
And the risk is high. Even extremely low current can cause death from respiratory paralysis, if the victim is unable to release the "hot" object and the current passes through the chest for an extended time. The most common cause of death from electric shock results from ventricular fibrillation (loss of the heart's ability to pump, which leads to death within minutes). If you are on a scaffold or ladder, any shock can cause you to lose your balance and fall resulting in injury or death.
GFCIs (ground fault circuit interrupter) were developed in 1961 to reduce
these hazards, and OSHA requires their use on construction sites for all
120-volt, single-phase, 15 and 20-amp receptacle outlets which are not
part of the permanent wiring of the building or structure. 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. It is much more effective than a standard circuit breaker
or fuse, which are really designed to protect wiring and equipment not
Ground fault circuit protection can be part of a circuit breaker or built within a receptacle. The circuit breaker protects the entire circuit while receptacles can be wired to protect only the individual device and/or to also protect the receptacles on the load side of the GFCI device. Providing more GFCIs or shorter circuits can prevent tripping caused by the cumulative leakage from several tools or by leakage's from extremely long circuits. It is also a good practice to limit exposure of connectors and tools to excessive moisture by using watertight or sealable connectors. Portable GFCIs are also available - use them while waiting for your employer to comply with OSHA standards.
A portable GFCI you can keep with you
OSHA regulations allow employers on construction sites to maintain an "extensive assured equipment grounding conductor program," including daily inspections and periodic testing by one or more competent persons, as an alternative to the use of GFCI. But because it is impractical to meet all the requirements of a grounding program, GFCI protection is easier and better.
While critical to safety, effective GFCI protection is commonly lacking on construction sites. In 1999, ground fault protection violations on construction sites were the tenth most common reason employers were cited. What is the situation where you work?
Over four hundred workers die each year from contact with electrical energy, the fifth leading cause of workplace death. Construction workers, including laborers, electricians, painters and others account for almost half the total. Direct or indirect contact with power lines is the most common cause of electrocution.