Electrical wiring in the United Kingdom lawnmower does it need an RCD?" The risk of electrical shock on construction sites can be reduced by several measures, including reduction of the normal 230 volt distribution voltage to 110 volts for electrical lighting and power tools. By using a centre-tapped transformer, each conductor of the circuit is only at 55 volts with respect to earth. This reduces the chance of dangerous electrical shock when using power tools in wet locations. Where 230 volts must be used, a residual current device (RCD) can be used to detect small leakage currents and automatically isolate faulty equipment. In sites where hazardous
Electrical equipment in hazardous areas Electrical equipment in hazardous areas In electrical engineering, hazardous locations (sometimes abbreviated to HazLoc, pronounced "Haz·Lōk") are defined as places where fire or explosion hazards may exist due to flammable gases, flammable liquid–produced vapors, combustible liquid–produced vapors, combustible dusts, or ignitable fibers/flyings present in the air in quantities sufficient to produce explosive or ignitable mixtures. Electrical equipment that must be installed in such classified locations should be specially designed and tested to ensure it does not initiate an explosion, due to arcing contacts or high surface temperature of equipment. The introduction of electrical apparatus for signaling or lighting in coal