A space heater feels like the easy answer to a cold bedroom. Plug it in, set it low, and fall asleep warm. But fire safety officials give a clear answer on running one all night: don’t.
What the safety groups say
The National Fire Protection Association (NFPA) and the U.S. Consumer Product Safety Commission (CPSC) both say the same thing: turn a space heater off when you leave the room or go to sleep. A heater that runs for hours with nobody watching is the setup for most heater fires.
NFPA reports that space heaters cause a large share of home heating fires, and an even larger share of the deaths from those fires. Most of those fires start the same way: the heater is too close to something that can burn.
Why nighttime is the risky time
While you sleep:
- Blankets slide. A comforter that slips off the bed can land on or against the heater.
- Nobody notices smells or sparks. A hot plug or a scorched cord gives warning signs, but only to someone who is awake.
- Furniture and curtains are close. Bedrooms are small, and the heater often ends up near the bed, a nightstand or the drapes.
The rules that keep a heater safe
If you use a space heater while you are awake and in the room, these are the official basics:
- Keep 3 feet of clear space around it. Beds, chairs, curtains, clothes and paper all stay back.
- Plug it straight into the wall. Never use an extension cord or a power strip. Heaters pull a lot of power and can overheat them.
- Pick a heater with automatic shutoff. Look for a tip-over switch and overheat protection.
- Look for a safety mark. A label from a testing lab such as UL, ETL or CSA means it was tested.
- Set it on a hard, flat floor. Never on a rug, a bed or a table.
- Check the cord and plug. If either feels hot or looks damaged, stop using the heater.
- Keep a working smoke alarm in or near every bedroom, and test it monthly.
How to stay warm at night instead
- Warm the bedroom with the heater before bed, then switch it off and unplug it.
- Use flannel sheets and an extra blanket.
- Wear warm socks.
- Close the bedroom door and block drafts under it with a rolled towel.
- If you use an electric blanket, follow its directions and do not tuck it under the mattress.
The short answer
A space heater is fine for warming a room while you are there to watch it. When it is time to sleep, turn it off and unplug it. The safety rules are simple, and they are the same every winter.
Sources
- National Fire Protection Association (NFPA), Heating safety tips: https://www.nfpa.org/education-and-research/home-fire-safety/heating
- U.S. Consumer Product Safety Commission, Space heater safety: https://www.cpsc.gov/Safety-Education/Safety-Guides/Home/Portable-Heaters
- U.S. Fire Administration, Heating fire safety: https://www.usfa.fema.gov/prevention/home-fires/prevent-fires/heating/
