Obstructions
Space heaters can overheat if they are not situated in a clear area. Keep each heater at least three feet away from curtains, drapes, furniture and walls.
Tipping Over
A space heater can overheat if it tips over. It's best to only use space heaters with automatic tilt sensors, which shut off the heater if this happens. This feature is especially important if you have small children or pets.
Covered Heater
A partially covered space heater can easily overheat. Don't attempt to dry mittens, socks, shoes or other clothing items on top of or directly in front of your space heater.
Industrial and Outdoor Heaters
Heaters with greater than 1,500 watts are not intended for use inside a home or small building, and can overheat if not given very wide air clearance.
Electrical Considerations
Even residential-use electric space heaters require high wattage, and should not be plugged into outlets that provide electricity to other products. Also, using an extension cord can cause the space heater, cord or outlet wires to overheat and ignite.