AC vs. DC

AC vs. DC

It’s not the voltage that kills, but the current. There are two types of electrical current used in construction — alternating current (AC) and direct current (DC). AC alternates or changes its direction of travel many times a second whereas DC flows in only one direction. AC is the type of electricity used at most construction sites and in homes because it can be transformed to lower voltages and transported long distances without losing much power.

• Voltage, by its very nature, is a manifestation of potential energy. Both AC and DC currents can be deadly.

• 100 volts AC in the home and as little as 42 volts DC have killed people. The real measure of a shock’s intensity lies in the amount of current (in milli-amperes) forced through the body.

• Any electrical device used on a house wiring circuit can, under certain conditions, allow a fatal amount of current to flow. Use safe work practices when working around electricity of any voltage.

• Any voltage is considered to be capable of delivering dangerous amounts of current.

• Use GFCI protection and an assured equipment grounding program on all circuits in construction.