The potential risk to users of a device with an electrical fault is very great. At worst an electric shock can be fatal. An electric shock happens when a person touches a live component or wire. This could be due to an electrical fault, such as component failure or a wire coming loose, or it could be due to an error made by the person, such as cutting a cable when mowing the grass or working on an electrical device without isolating it from the supply. When a person touches a live component or wire, the electrical current will try to find a path to ground through the body. In doing so, this can cause serious injury or death.
An electric shock could cause:
- burns along the path of the electric current
- burns where the current entered and left the skin
- muscle spasms
- shallow breathing
- rapid pulse
Electric shocks can vary in severity for several reasons. The size of the electrical current that passes through a person will have a large affect on the severity of the shock - the higher the current the more dangerous the shock. Note that it is the current that does the damage, not the voltage. A lethal current is normally between 100 and 150 milliamps, which is actually very low compared to the current flowing normally in electrical devices. The current that flows largely depends on the resistance of the body.