Is it safe to use space heaters?

Odds are someone in your office or workspace has already fired up their space heater. “It’s chilly in here” is the best reason to do it. More than likely the unit will run safe and do its intended job; after all, most modern space heaters are compact electric units with overheating protection and automatic “tip-over” protection built in. Furthermore, the unit is probably UL listed or has some similar designation.

So why am I writing this blog about heaters? Because every year portable heaters cause millions in fire damage and increase the threat to human life. Yep, that little heater under your desk. In fact, Minnesota Department of Health reminds us that not only is there a direct risk of fire from the heating element of the unit, but also an increased risk of fire due to overloading the building’s electrical system and the circuit used to power the unit. For this and other reasons, the Minnesota State FireMarshal’s Facebook page has provided these guidelines for portable heater use:

• Never leave a space heater unattended.
• Plug space heaters directly into outlets, not power strips.
• Do not warm clothes on space heaters.
• Do not sleep with space heaters on.
• Keep anything combustible three feet from a space heater.

Here are a few more considerations:

• Follow your city use policy. If your city has a policy against any or all portable heaters, don’t use them.
• If your city requires permission from maintenance staff ask for permission because they may be able to offer alternative solutions.
• Be sure the cord is in good condition.
• Do not use heaters in high traffic areas where they or their cords can become a trip hazard.
• Never use unvented combustible gas or liquid fuel heaters indoors.

What about in the shop? Need some quick heat in the work bay or near the floor while working on something in the shop? Be mindful of what else is nearby. Gasoline, for example, produces ignitable vapors that are three to four times heavier than air and can travel for great distances along the ground. Gas vapors tend to accumulate in low or enclosed spaces. Use of an open flame heater in this environment is highly dangerous. 

Read the owner’s manual for the heater you plan to use. Most liquid fuel heaters are not designed to be used indoors. Always follow the manufacturer’s intended use.

Along with the obvious fire or explosion hazard of using liquid fuel heaters (LP, #2, Kerosene, etc.), be mindful of carbon monoxide (CO) emissions. We all know CO is odorless and colorless — and deadly. It is generated by incomplete combustion of fossil fuels. Unless you have CO detection in the shop, there is no way to know the CO level. This seems like a good time to mention the warning signs of CO poisoning: headache, dizziness, weakness, upset stomach, vomiting, chest pain, and confusion.

If you are feeling any of these flu-like symptoms or notice your coworkers’ exhibiting signs, immediately get yourselves to fresh outdoor air and call 911 for help.

The first signs of chilly weather always result in space heaters being fired up. Followed quickly by the first reports of fires, or worse, injury or death caused by their use. Don’t be a statistic. Talk to your maintenance department about improving the indoor comfort of your office or workspace by use of the building’s HVAC system rather than portable heaters when possible. If a space heater is your only option, select a modern unit with safety features that prevent fire and CO illness, select the right one for your application, and follow the manufacturer’s safety recommendations. Oh, and turn it off when you’re not at your workstation, for safety and energy conservation. The question is, “Is it safe to use of space heaters?” The answer is “yes” if you follow good safety practices.

If you have questions about the safe use of space heaters or want to talk about any safety related questions or concerns, contact your League of Minnesota Cities Loss Control Consultant. We’re here to help.

Additional Resources:

1. https://www.health.state.mn.us/facilities/regulation/infobulletins/ib02_16.html
2. https://www.facebook.com/StateFireMarshal/photos/a.211377991209/10158574365006210/?type=3
3. https://dps.mn.gov/divisions/sfm/for-families/Documents/Fact%20sheets/Alternative-heating-fact-sheet.pdf
4. https://www.nfpa.org/-/media/Files/Public-Education/Resources/Safety-tip-sheets/PortableHeaterSafety.ashx
5. https://www.nfpa.org//-/media/Files/Public-Education/Resources/Safety-tip-sheets/Heating_Safety.pdf

Submitted by: Marc Dunker, Loss Control Consultant