The District operates four air monitoring stations within its tri-county jurisdiction: Jacobs Station (Humboldt County), Humboldt Hill Station (Humboldt County), Crescent City (Del Norte County), and Weaverville Station (Trinity County). Air monitoring data collected at these stations is reported to the EPA for determining compliance with the Federal Ambient Air Quality Standards.

Air monitoring stations are typically small buildings which contain sampling and monitoring equipment. They are usually accompanied by a meteorological station to measure wind speed, direction, temperature, and humidity. Meteorological information is collected to assist in determining the origin of pollution events and is used when preparing healthrisk assessments.

The California Air Resources Board (CARB) conducts routine audits of District equipment and procedures for quality assurance purposes. The most recent local air quality data is available historically from each of the District's monitoring stations. If you would like more information that what is provided on this website please contact District staff.

The District maintains a current Annual Network Plan for Ambient Air Monitoring which explains how air pollutants are monitored within the District. The plan both summarizes the previous year's air quality data and discusses any expected changes in the monitoring process. Each year the plan is updated and the Proposed Draft Annual Network Plan for Ambient Air Monitoring is publicly noticed in June of each year to garner public comments, and then provided to the EPA. Please contact District staff for further information.

During wildfires, the District provides air quality information about wildfire smoke and monitors the smoke impacts from active wildfires. The District accesses air quality information (Particulate Matter - PM2.5) from both its existing regional air monitoring stations and portable PM2.5 air monitors (EBAMs) that have been deployed as appropriate by the District, the USFS, and CARB.