Space Heater Safety: The Rules That Prevent Fires

Few heating fires start with portable heaters, but many of the fatal ones do.

The U.S. Fire Administration (USFA) reports that heating is a leading cause of home fires: in 2021, an estimated 32,200 home heating fires caused about 190 deaths, 625 injuries, and $442 million in losses. Portable heaters were only 3% of home heating fires in 2017–2019 but 41% of the fatal ones. The Consumer Product Safety Commission (CPSC) estimates that portable heaters, including electric space heaters, were involved in an average of 1,600 fires a year from 2020 to 2022, with about 70 deaths and 150 injuries a year.

The single most important rule.

CPSC says to keep portable heaters at least 3 feet from drapes, furniture, bedding, and other combustible materials. USFA applies the same distance to anything that can burn near any heat source, including fireplaces, wood stoves, and radiators. Measure it once: 3 feet is farther than most people leave between a heater and a bed or a sofa. Keep the space clear of clothing drying nearby, papers, and pet bedding too.

Heaters draw more current than most things you plug in.

Plug an electric space heater directly into a wall outlet, never into an extension cord or power strip, CPSC says. USFA’s electrical advice explains why: do not overload outlets or power strips, insert plugs fully, replace outlets that do not hold a plug snugly, and replace any appliance with a cracked, damaged, or loose cord. A heater that trips its breaker is a sign the circuit is already loaded; see why a breaker keeps tripping before moving it to another outlet on the same circuit.

Unattended heat is where fires start.

Turn space heaters off when leaving the room or going to bed (USFA) and when sleeping (CPSC). Never use an oven to heat your home. CPSC adds that gas appliances such as ranges, ovens, and clothes dryers should never be used for heat, and that unvented fuel-burning appliances should never run in a room where people are sleeping. If a room needs a heater all night to be livable, the house has a heating or air-leak problem worth fixing; see heat pump or furnace.

Refueling and carbon monoxide.

For fuel-burning portable heaters, CPSC says never to refuel while the heater is running: turn it off and let it cool first. Fuel-burning heating equipment can produce carbon monoxide, an odorless, colorless, deadly gas, when it is misused, poorly maintained, or badly vented. CPSC recommends having a professional inspect fuel-burning heating systems — furnaces, boilers, fireplaces, wood stoves, water heaters, chimneys, flues, and vents — every year, and USFA recommends yearly cleaning and inspection of heating equipment and chimneys.

The backup plan.

CPSC recommends smoke alarms on every level of the home and inside each bedroom, and carbon monoxide alarms on every level and outside sleeping areas, battery-powered or with battery backup, ideally interconnected so that when one sounds they all do. Test them monthly and replace batteries at least yearly, or install alarms with sealed 10-year batteries; see why a smoke alarm chirps. Before using an older heater, check whether it has been recalled at cpsc.gov/recalls. To see what a heater adds to the electric bill, see what a space heater costs to run.