Heated Enclosure Hazards (CO and Fire)
Construction and general industry · Ver en español
Talking points
- Fuel-burning heaters (propane, kerosene, diesel) consume oxygen and produce carbon monoxide. In an enclosed space, CO can reach lethal levels in minutes.
- Never use an unvented fuel heater in an enclosed or poorly ventilated space. Indirect-fired heaters that vent exhaust to the outside are the safe alternative.
- Carbon monoxide is colorless and odorless. A CO monitor is the only reliable detection method. Place it at breathing height in the work area, not near the ceiling.
- Maintain required clearances between heaters and combustible materials — typically 36 inches on all sides. Tarps, plastic sheeting, and stored materials can ignite from radiant heat.
- Refuel heaters only when they are off and cool. Fuel spills on hot heater surfaces can ignite instantly. Keep a fire extinguisher within reach of every heating unit.
Ask the crew
Are we using any fuel-burning heaters inside enclosures today — and do we have a CO monitor in the space?
Standards this talk is built on
A toolbox talk is a short safety briefing. It supports the training a standard requires; it does not replace it.
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Sign-in sheet
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