COVID-19 revealed a need for mobile medical testing sites to provide an area for testing but minimize exposure to health care workers and permanent health care facilities. 

Some of these sites may use tents or similar structures that may need to be heated. Due to the hazards of open-flame heating, the Minnesota State Fire Code (MSFC) has limitations on heaters in tents and membrane structures. 

Tents need to be fire retardant

The fire code requires that tents and membrane structures be flame retardant. “Flame retardant" does not mean the material will not burn. Flame retardant materials are resistant to ignition from a relatively small open flame (like a match or small burner). Flame retardant treatments are not intended to protect against ignition from large open-flame devices (like a furnace or open-flame heater).

Open flames are not allowed

Here are some of the restrictions:

• Portable outdoor gas-fired appliances are prohibited inside tents and membrane structures.
• Open-flame devices and similar arrangements are not allowed inside of or within 20 feet of tents and membrane structures when they are open to the public.
• Heating equipment needs to be at least 10 feet from exits or combustible materials (even when not open to the public).

Preferred heating methods

• Indirect heat: A heater located outside and a safe distance from the tent where warm air is blown into the tent.
• Electric heat: Must be listed by a nationally recognized testing laboratory.

If open-flame heaters are being used, they should be:

• 20 feet from the tent (if open to the public).
• 10 feet from exits from the tent.

If LP gas is the fuel source for the heaters, the following separation distances are required:

• Containers of 500 gallons or less — 10 feet from the tent.
• Containers of more than 500 gallons — 25 feet from the tent.