Proper use and care of extension cords is something that most of us take for granted. The consequences of this may be fatal.
When using an extension cord be sure that it is in good condition. Inspect it for frayed or damaged insulation. If you are using a grounded (3-prong) extension cord be sure that the ground pin has not broken off or been removed from the plug end of the cord. Discard the cord if it is not safe for use.
Always use the right cord for the job. Indoor cords should not be used outdoors, however, an outdoor rated cord may be used indoors. When using an extension cord outdoors be sure it is kept away from water and damp areas and that it is protected by a Ground Fault Circuit Interrupter.
Be sure to use the right size cord for the job. When you use an extension cord you increase the length of the electrical circuit, which in turn adds resistance. With the increased length and resistance in the circuit, the amperage increases, which can be dangerous if the cord is not sized properly. As well, the increased amperage can harm or cause premature failure of appliances especially those with electric motors (i.e. power tools). Avoid using longer cords than necessary. Use the chart below as a guideline for sizing extension cords accordingly.