An electrician's plea: Don't plug these 7 appliances (including AC units) into extension cords

Extension cords are generally a safe solution for running power to electronics that are too far from the nearest wall outlet. But the operative word here is "electronics," which is not as all-encompassing as some people might think.

Appliances (like refrigerators and toaster ovens) are obviously electronic devices, but they're in a different class from most electronics because of the amperage demands they need to function. 

Why you shouldn't plug everything into an extension cord

Extension cords are manufactured with a maximum capacity to handle electrical current, which is determined by the size or gauge of the wire used in the cord. For instance, a 16-gauge extension cord can handle a maximum of 13 amps, while a 14-gauge cord can handle up to 15 amps (or 1,800 watts), the same as a standard wall outlet in the US.

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