Carbon Monoxide

Carbon monoxide is a colorless, odorless, toxic gas commonly formed when carbon-containing fuel is not burned completely. Motor vehicles are the predominant source of carbon monoxide in the Puget Sound region.

What are the impacts of carbon monoxide?

Carbon monoxide chemically combines with the hemoglobin in red blood cells to decrease the oxygen-carrying capacity of the blood. It also weakens the contractions of the heart, reducing the amount of blood pumped throughout the body. It can also affect the functioning of the lungs and brain. People with heart disease and pregnant women are especially at risk of the effects of carbon monoxide.

How are carbon monoxide levels in our region?

Carbon monoxide levels are well below federal standards and no longer considered a pollutant of concern in the Puget Sound area. This region was designated as “attainment” status in 1996 and has not violated the carbon monoxide standard since 1990. The Department of Ecology monitors carbon monoxide levels.

For more on carbon monoxide:

• Carbon monoxide fact sheet (PDF 0.1MB)

• 2005 Air Quality Data Summary (PDF 1.4MB)

• CO/Ozone Stakeholders Group Final Report (PDF, 0.5MB)