I bought an electric space heater when my city was forecast for sub-zero temperatures.
The last time it got that cold, my gas furnace struggled to keep up. I wanted a backup heat source to take the chill out of the air or, worse — if the furnace broke.
Portable space heaters can help warm a room in your home or keep you warm in a cold office, but these can be a fire hazard.
If you have a portable space heater or are thinking about getting one, here are features to look for when choosing a space heater and how to use it safely.
How many U.S. homes use portable space heaters?
In 2015, 37% of U.S. households used a secondary heat source. The most common secondary source was portable electric space heaters, followed by fireplaces.
How often do space heaters cause fires?
Portable space heaters cause around 1,700 house fires annually in the United States, according to a 2022 report by the Consumer Product Safety Commission. Local fixed heaters cause around 5,000 house fires. Cooking equipment caused the most house fires — about 165,600 per year.
When I examined a 2022 report from the National Fire Protection Association, it told a different story.
For residential fires caused by home heating equipment, space heaters caused 33% of those fires. Space heater fires caused 9 out of 10 deaths and 4 out of 5 injuries in house fires caused by heating equipment, according to the NFPA.
When space heaters catch fire, they’re disproportionally deadly.
What causes portable heaters to catch on fire?
In most cases, space heaters catch on fire due to user error. Most common reasons:
- The heater is placed too close to other objects. Keep it at least 3 feet away and on a flat, non-flammable surface.
- It overheats. Only plug the heater and nothing else into the outlet, and don’t use extension cords. Don’t run it too long (read the product instructions).
- It’s damaged. Inspect the appliance, including the cord, before every use.
- It’s left unattended. Turn it off and unplug it when you leave the room.
This chart shows the causes of portable heater fires in homes and was compiled from a 2022 report from the U.S. Fire Association. Note that percentages don’t add to 100% because sometimes, a cause wasn’t specified, or there were multiple factors causing ignition.
What type of space heaters can catch fire?
They all can.
I made this chart from the 2022 U.S. Fire Association report data. Caveat: the report doesn’t talk about the raw numbers of the types of space heaters in use. While this data suggests catalytic heaters cause the fewest fires, I don’t know if it’s because that’s true or if there are fewer catalytic heaters in use.
Safety features to look for when buying an electric space heater
1. Look for the Underwriter Labratory seal, or UL Mark or ETL Listed Mark, to make sure the product meets product safety standards as set forth by a Nationally Recognized Testing Laboratory.
2. Choose a heater that will automatically shut off if it gets too hot, also known as a thermostatically controlled heater. This feature helps to avoid wasting energy and overheating a room. “Thermostatically controlled” means there is an internal thermostat to regulate the temperature.
3. Match the heater capacity to the size of the room you intend to heat. On the box or in the product description, look for the intended room type and size. Don’t use a heater designed for a large room in a smaller space because you’ll increase your risk of overheating or starting a fire.
4. Make sure the heater has a tip-over switch, so it will automatically shut off if it falls over.
Tips for how to use a space heater safely
1. Does your home have working smoke detectors? When was the last time you changed the batteries or pressed the button to test them? Only 41% of homes were confirmed to have working smoke detectors in fires caused by space heaters.
2. Check your heater for recalls by searching for it in the CPSC database.
You might find it easier to search by product category. Here are the search results for recalled portable electric heaters.
Here’s another search query for recalled heaters or heating systems. Look through the database, search for your product specifically, and register your heater with the manufacturer to be notified of future recalls.
3. Read the product instructions and follow them every time. Refresh your memory by rereading the instructions at the beginning of winter or if you haven’t used your space heater in a while.
4. Check for signs of damage to the unit, cord, or plug before each use. If damaged, cut the cord with scissors and dispose of it. Cutting the cord makes sure someone doesn’t find it while it’s waiting for the garbage collectors and takes home an unsafe heater.
5. Plug the heater directly into a wall outlet. Don’t plug anything else into that circuit. Don’t use extension cords with space heaters. Electric heaters use a lot of electricity, and overloading an outlet can cause fires.
6. Use the 3-feet rule. This is the leading cause of space heater fires! It needs to be at least 3 feet (1 meter) from anything else so that it will have proper airflow to the machine and avoid igniting the surroundings.
7. Place it away from children and pets, and don’t block walkways to a room. Ensure the heater is not blocking a door.
8. Set it on a smooth, flat, non-flammable surface. Read your product instructions to see if it’s safe to use on a tabletop or if it should be placed on the floor.
9. While using it, check it every so often to make sure the cord and plug aren’t getting hot. If it is, unplug and discontinue use. Perhaps it’s been running too long, or you’re overloading the outlet, or your house’s electrical system needs an inspection by a qualified electrician.
10. Turn off and unplug the space heater when you leave the room.
11. Do not use a space heater when you’re sleeping.
12. Don’t run it for longer than the instructions allow.
Visit the National Fire Protection Association for more on using space heaters safely. Also see this tip sheet from the CPSC.
