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Carbon Monoxide (CO) Pollution in Outdoor Air

Technical Data and Reports on Carbon Monoxide Measurements and SIP Status

EPA collects data from the states and regions on their air quality and state implementation plan (SIP) progress. This information is compiled in a database, and used to create reports, trend charts, and maps.

SIP status reports

Reports for nonattainment area SIP requirements

Reports for infrastructure SIP requirements

SIPs approved by EPA

Air quality data

AirNow: see real-time air pollution data in the United States.

Air Quality Trends: View CO levels in ambient air; measured nationally, regionally, and locally; up to 2015.

Design Values: view statistics that describe the air quality status of a given area relative to the level of EPA's National Ambient Air Quality Standards. These Excel reports are listed by pollutant.