The next time you reach for an extension cord, remember this: just because a particular cord is long enough, it’s not necessarily the right one for the job. It can be easy to think that length is the only characteristic that sets one extension cord apart from another, but there’s much more to it than that!
Power extension cords aren’t all the same: they’re manufactured to be used in different environments, and to carry varying amounts of electrical current. By basing your choice of extension cord on each task’s specific requirements, you can greatly reduce the risks of fire, electrical shock, and injury that come with improper use.
Extension cords are classified for either indoor or outdoor use. What’s the difference between the two? The insulation, or jacket, of an outdoor-rated extension cord is made of a tougher material, which is designed to withstand temperature changes, moisture, UV rays, and (sometimes) chemicals. While it’s fine to use an outdoor power cord indoors, never use an indoor-rated extension cord for an outside job… doing so could cause electric shock or create a fire hazard.
Any electrical cord, extension or otherwise, contains an inner metal conducting wire, which carries electrical current from one end to the other. The thickness of this conductor is referred to as its gauge. Gauge is indicated by a number; the lower the number, the thicker the wire is. A wire’s thickness directly affects the amount of current (or wattage) it can carry over a certain distance.
The number of watts an extension cord can safely transmit (given its length and gauge) is known as a wattage rating. Before plugging an appliance or power tool into an extension cord, it’s extremely important to be sure that the power demand (or pull) of that device doesn’t exceed the cord’s wattage rating. On the same note, if you’ll be powering multiple devices from one extension cord, calculate their combined energy requirements and make sure that the total isn’t higher than the wattage rating for that cord. Never use an extension cord to supply more wattage than it’s rated for, since overheating and fire may occur.
A few things to know before you plug in:
- For your protection, power cord labels are printed with handy product specs that tell you the cord’s length, size (wire gauge), wattage, and proper usage environment . So before you unwind that cord and hook it up to a power tool, read the label… checking only takes a few seconds, but it might just save you from injury or property damage!
- Make sure to use your GFCI.
- Don’t use extension cords with cut or damaged insulation… exposed conducting wires can put you at risk for fire, burns and electrical shock.
- Do not cut, file, or otherwise alter an extension cord’s grounding pin or plug blades to make it easier to plug into an outlet! If the extension cord plug doesn’t fit into an older outlet, have an electrician replace the receptacle.
- Extended exposure to outdoor conditions can cause cords to deteriorate, so whether they’re rated for indoors or outdoors, store all extension cords inside when they’re not in use.
- Regardless of whether or not it’s being used, as long as a power extension cord is plugged into an outlet, it’s conducting electricity. To avoid potential safety hazards, always remember to unplug extension cords when they’re not in use.