Carbon Monoxide
Carbon monoxide (CO) is a colorless, odorless gas from burning fuel. It replaces oxygen in your blood and can knock you out and kill you before you realize anything is wrong.
- Construction
- General Industry
Common jobsite sources
- Gas-powered cut-off saws, plate compactors, pressure washers, pumps and generators used indoors or in trenches
- Propane forklifts, floor buffers and concrete trowels in buildings
- Fuel-burning space heaters in enclosed or tented areas
- Vehicles idling near air intakes or loading docks
Symptoms
Headache, dizziness, nausea, tiredness, confusion, chest pain, then collapse. Symptoms often get better when you go outside and come back when you return.
If someone has symptoms: get them (and everyone else) into fresh air immediately, shut off the source if safe, and call 911. CO poisoning can cause lasting brain and heart damage.
Prevention
- Don’t use gas-powered equipment indoors or in enclosed spaces. Use electric or battery tools.
- If fuel-burning equipment must be used inside, provide ventilation and monitor CO levels continuously with direct-reading meters.
- Place generators and compressors outdoors, away from doors, windows and air intakes.
- Maintain engines and heaters.
- Wear a personal CO monitor in at-risk work.
Limits
OSHA’s permissible exposure limit is 50 ppm averaged over 8 hours. NIOSH recommends 35 ppm with a 200 ppm ceiling.
Standards & references
- 29 CFR 1910.1000: Air contaminants
- OSHA Fact Sheet: Carbon monoxide poisoning
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