The number of people that believe that normal household current is not lethal or that power lines are well-insulated and do not pose a hazard is alarming. Electrocution may be caused by contact with an object as seemingly innocuous as a broken light bulb or as lethal as an overhead power line. The current drawn by a tiny nightlight bulb may be only a few watts, but the power in the socket is 120 volts, which could pass from hand to hand or hand to foot across the chest and is sufficient to cause electrocution.
According to the International Electrical Safety Foundation, more than 30,000 non-fatal shock accidents occur each year in homes nationwide, and there are an estimated 60 fatal electrocution accidents associated with small appliances, power tools, and lighting equipment. Appliances that use water can be particularly dangerous because water is a good conductor of electricity. Water that runs down the side of an electric kettle and reaches the filament, for example, may cause a serious shock. Other appliances, such as hair dryers, curling irons and toasters also pose a risk of shock. If your hair dryer or curling iron starts to smell like it is burning, unplug it immediately. If you can’t get the toast out of the toaster, pull the plug before you stick something inside to try to grab it.
Plug sockets are another common cause of shocks and electrocution at home. The normal voltage of a household plug socket is 120 volts, while stove and dryer plugs are typically a very dangerous 240 volts. This is enough to kill a healthy grown adult. Use care or call an electrician if a plug socket or a light switch is making any strange buzzing sounds or feels hot. If you know how, you should trip the circuit breaker for that outlet so that the electricity is off. It is also important to protect children from access to plug sockets. Every year children are seriously injured or killed because they had access to a plug socket and pushed their fingers or some object like a key or a spoon handle into it. There are simple inserts you can get to “child proof” electric outlets.
Coming into contact with live overhead power lines is the most frequent type of electrocution on a job site, and often happens to homeowners too. Severe burns, permanent nerve damage and even heart attacks can occur when someone comes into contact with an electrical power line. Workers directing a crane or even standing near a crane or other boomed vehicle that contacts a power line are in danger of electrocution. These exposures can be greatly reduced by creating a physical barrier, insulating the power line, or following guidelines for required clearance. The same precautions should be taken at home. Never use a ladder near the power lines into your house. Those lines have 240 volts of electricity in them, and an aluminum ladder is a great conductor, so if the end of the ladder hits the wire in a spot without enough insulation, the electricity will come right down the ladder to you.
Improper grounding of equipment or electrical circuitry on the job site is another common way that workers are injured. If the frame of a piece of electrical equipment or machinery does not have a grounding conductor attaching the frame to ground and an electrical fault occurs, anyone touching that frame and any other object at ground potential would receive an electrical shock. Similarly, damaged extension cords or extension cords with their ground prong removed can expose workers to the danger of electrocution. It is important to check equipment to make sure that it is not damaged.
The United States Center for Disease Control offers many publications on electrical safety for the home and workplace. You can download them for free at http://www.cdc.gov/niosh/topics/electrical/.