Preventing carbon monoxide poisoning

release from the Minnesota department of commerce

Each year about 50,000 people visit emergency rooms in the United States for carbon monoxide (CO) poisoning, and more than 500 die each year from this silent, odorless, colorless gas.

CO can build up to dangerous concentrations indoors when fuel-burning devices—furnaces, water heaters, gas or kerosene space heaters, gas boilers, gas ranges and ovens, gas dryers, charcoal or gas grills, fireplaces and wood stoves, vehicles, and yard equipment—are not properly vented, operated or maintained. CO is most common in the winter months, when a heating system malfunctions in a home or when a car engine is left running in a garage.

When CO is inhaled into the lungs it displaces the oxygen in the blood stream and affects all major organs and muscles. The higher the concentration of CO, the more rapid the oxygen displacement and the greater the health risk. Beginning at CO levels of 36-99 part per million (ppm), symptoms of CO poisoning include headaches, fatigue, shortness of breath, nausea, vomiting, and confusion. Lower levels (5-30 ppm) over extended periods of time may also cause symptoms. At 800 ppm, nausea, dizziness and convulsions may occur, and death can occur within 2 hours. At 1,600 ppm, death can occur within 1 hour.

Tips to prevent CO poisoning

The Minnesota Department of Health offers the following tips to help prevent CO poisoning:

  • Install UL-standard CO alarms; Minnesota law requires CO alarms in every single family dwelling and every dwelling in a multifamily dwelling (Minnesota Statute, 299F.51).
  • Have a qualified technician inspect your fuel-burning appliances each year to ensure they are adequately vented and properly maintained. CO testing should be part of the inspection.
  • Do not idle cars in garages, both attached and unattached, for any length of time. Dangerously high levels of CO will accumulate even if the garage door is open.
  • Provide adequate ventilation when using a fireplace, wood stove, or space heater.
  • Portable propane camping equipment and gas barbecues are approved for outdoor use only. Never use them inside cabins, tents, fish houses, or other enclosed shelters.
  • If your car is stuck in snow, make sure that the tail pipe is cleared before starting the engine.
  • During power outages, do not use gasoline engines or burn charcoal in enclosed spaces, including garages, even if the door is open.
  • For more information on CO poisoning, visit the Minnesota Department of Health and the Carbon Monoxide Safety Association at