Space heaters pose health risks primarily through poor air quality and safety hazards. They can severely dry out indoor air, causing respiratory irritation, dry eyes, and nosebleeds. Additionally, unvented fuel-burning models emit dangerous fumes, while electrical units present severe fire and overheating hazards if used improperly.
It's best to run a space heater only when you really need one, such as when you're warming a room you'll be in for a few hours at a time. Never leave space heaters on overnight or unattended for long periods because they can create a fire hazard.
While room heaters provide warmth during chilly winters, their prolonged use can lead to certain side effects that may impact health and comfort. Dry air: Continuous use of a room heater reduces humidity, causing dry skin, irritation in the eyes, and respiratory discomfort.
Using space heaters safely
Turn off a space heater when you leave the room or when you go to bed. Never leave a space heater unattended or running while you sleep. Put heaters on a level surface away from places where someone might bump into it and knock it over.
Dry Air and Respiratory Issues
Prolonged use of space heaters can lead to dry air in your home, which can cause a range of respiratory issues. Dry air can irritate the respiratory tract, leading to coughing, sore throats, and even exacerbating conditions like asthma.
These heaters are fueled by kerosene, natural gas, propane or electricity. All of these heaters can cause fires. Gas and kerosene heaters can cause buildup of carbon monoxide and nitrogen dioxide in your home. Carbon monoxide fumes can cause sickness or even death.
It takes time for your home to warm up and cool down. If you're not sure how long it takes, try turning the heating on about 30 minutes before you need it. You should turn it off 30 minutes before you'll stop needing it.
Recommended Usage Times
At Night: If you choose to use your space heater overnight, it's best to limit its operation to 4 to 6 hours on a lower setting.
Allergen Buildup
One of the most common reasons for heater sickness is unclean air. The EPA estimates that indoor air can be between 2 and 5 times more polluted than the air outside, and a faulty heater can ramp up those pollutants in no time.
The Risk of Space Heater Fires
One third of fires in the home are caused by space heaters.
Broadly, heat pumps are the most efficient form of heating. They can be more expensive than a furnace, especially if you purchase a geothermal heat pump. However, geothermal heat pumps are one of the cleanest heating options on the market. A geothermal heat pump can produce 1/6th the CO2 of a natural gas furnace.
The safest space heaters are oil-filled radiators and modern ceramic heaters with built-in safety features like tip-over sensors, automatic overheat shutoff, and cool-touch exteriors. Always choose models that are ETL or UL certified and keep them at least three feet away from flammable items.
Key points about carbon monoxide poisoning
A common source is unvented space heaters. Symptoms of CO poisoning include headache, dizziness, weakness, nausea and vomiting, rapid heartbeat, shortness of breath, seizures, chest pain, disorientation, and loss of consciousness.
Never leave a space heater running for long periods of time, and especially not overnight; it is best to use them intermittently; depending on your situation, a suggested practice would be to turn it off/unplug it for 10 minutes every hour if you depend on its use for longer periods.
Electric small space heaters can be more expensive to operate than combustion space heaters. Although they avoid indoor air quality problems, electric small space heaters still pose burn and fire hazards and should be used with caution.
Whilst they can start naturally, see Information note - Wildfire, it is estimated that 90% of all wildfires across the globe are caused by humans. About 30% of those are started as a deliberate act of arson, whilst 70% are started accidentally or as a direct result of human carelessness.
Portable electric heaters are high-wattage appliances that have the potential to ignite nearby combustible materials like curtains, beds, sofas, paper, clothing, and flammable liquids. If ignition results from a heater left on and unattended, a major fire could result.
The 30-30-30 rule in wildfire science is a simplified forecasting guideline used by fire officials to identify when weather conditions are prime for extreme and erratic fire behavior.
Cigarette smoking is the major cause of lung cancer and chronic obstructive pulmonary disease (COPD), which includes chronic bronchitis and emphysema. Cigarette smoke can narrow the air passages and make breathing more difficult.
Symptoms to Watch For
If you're experiencing frequent headaches, dizziness, nausea, or flu-like symptoms, your heater could be the culprit. Dry skin, irritated eyes, or worsening allergies are also common signs that your heating system might be circulating dust, mold, or other allergens.
Toasted skin syndrome, also called erythema ab igne, is a skin condition that comes from repeated and prolonged exposure to low levels of heat and occasional repeated high levels of heat. The heat is warm enough to damage your skin over time.
Fire safety experts and consumer protection agencies, including the Consumer Product Safety Commission, strongly advise against leaving a space heater on all night. The risk of a fast-moving fire occurring while you are asleep is significant, as you may not wake up in time to react to danger.
A heater-induced headache is usually caused by carbon monoxide (CO) exposure, severe indoor air dryness, or accumulated dust and pollutants circulating through your vents. Because a CO leak is a medical emergency, you should act immediately.
Sam Carter, radiator expert at Appliances Direct, says that though well-insulated homes will hold onto the heat much longer, "if you have an old home with poorer insulation, you may need to have your heating on for up to 10 hours a day in winter, or manage it with a low setback temperature (e.g. 15oc during 'off' ...