Local air quality (AQ) affects how we live and breathe. Like the weather, outdoor air quality can change from day-to-day or even hour-to-hour. Of special concern for human health is the polluting presence of fine particles of solid or liquid matter that measure 2.5 micrometers or less (<1/30th the diameter of a human hair). Those particles are labeled PM2.5 and are visible only by an electron microscope. Major sources of PM2.5 include motor vehicles, power plants, residential wood burning, forest fires, agricultural burning, dust, and other industrial processes.
Scientists report that air pollution containing PM2.5 increases the incidence rates of cardiovascular diseases, lung cancer, respiratory symptoms, asthma, and health outcomes during pregnancy and after birth. Deaths associated with PM2.5 are reportedly higher in socio-economically disadvantaged communities such as Pend Oreille County. Wildfires are a major contributor of PM2.5 and large conflagrations have increased in frequency, duration, and size. Wildfires also emit carbon monoxide, nitrogen oxides, and a wide range of toxic volatile organic compounds. Prior to 2019, there was no County-wide air monitoring effort to measure the health risk to residents and visitors from wildfire smoke.
Now, a community partnership involving Pend Oreille Conservation District, Selkirk Alliance for Science, Kalispel Natural Resources Department, Northeast Tri-County Health District, plus some public and private landowners is installing, interpreting, and posting several consumer-grade PurpleAir air monitoring devices. The mapped location of those PM2.5 stations and their 24/7 real-time measurements can be viewed at the Pend Oreille Conservation District website.
The EPA developed an index for daily air quality called the Air Quality Index (AQI) for PM2.5. Researchers know that PurpleAir measurements are precise between individual PurpleAir devices but are not necessarily comparable to Federal regulatory sensors that cost thousands of dollars, are difficult to install, and require a specialist to maintain. In fact, studies have shown that uncorrected PurpleAir devices overestimate PM2.5 values when compared to regulatory sensors. Until research correlates local PurpleAirmeasurements with those from regulatory sensors, the data presented in Monthly AQI Monitoring Reports by the partnership contains no Conversion Factor correction. Click here to view Monthly AQI Monitoring Reports.