Carbon Monoxide in Enclosed Parking Facilities, Service Stations, and Vehicle-Repair Facilities

Why am I being warned about potential exposure to carbon monoxide?

  • Carbon monoxide (CO) is on the Proposition 65 list because it can cause birth defects or other reproductive harm.
  • Exposure to carbon monoxide during pregnancy can affect brain development and cause loss of pregnancy.
  • Proposition 65 requires businesses to determine if they must provide a warning about exposures to listed chemicals

What is carbon monoxide?

  • Carbon monoxide is a colorless, odorless, and poisonous gas.  It is formed during the combustion of various fuels, including gasoline, diesel, natural gas, wood, coal, kerosene, propane; and plant-derived materials, such as tobacco.
  • Carbon monoxide can replace oxygen in the bloodstream.  Reduced levels of oxygen in the bloodstream during pregnancy can affect development of the baby’s brain.

How does exposure to carbon monoxide occur in enclosed parking facilities, service stations, and vehicle-repair facilities?

  • Exposure occurs by breathing air that contains carbon monoxide.
    • Carbon monoxide is released directly from vehicle tailpipes while the engine is running.
    • Carbon monoxide present in motor-vehicle exhaust can accumulate in garages, enclosed parking facilities, service stations, and vehicle-repair facilities.
  • During pregnancy carbon monoxide can pass from the mother to the baby.
Carbon monoxide is produced during combustion
People breathe contaminated air

How can I reduce my exposure to carbon monoxide in enclosed parking facilities, service stations, and vehicle-repair facilities?

  • Do not idle your car in enclosed parking facilities, service stations and vehicle-repair facilities. Carbon monoxide present in motor-vehicle exhaust can build up very quickly.
  • Limit the time spent in these facilities.

For more information:

Carbon Monoxide Fact Sheets and Resources:

Proposition 65:

  • California Environmental Protection Agency (CalEPA)
    Office of Environmental Health Hazard Assessment (OEHHA)

Scientific Information on Carbon Monoxide:

Posted May 2016

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