Protecting Public Health and the Environment.

DEQ's Monitoring Network

DEQ's air quality monitoring program encompasses operation of a monitoring network, laboratory analysis of air samples, and quality assurance activities to ensure data integrity. The program collects real-time measurements of ambient levels of air contaminants at more than 20 sites throughout the state. Integrated sampling methods are used at another 10 sites.

Our monitoring stations provide essential air quality data but do not cover the entire state. Low-cost alternative sensors are available for public use but continue to undergo lab and field tests to identify true performance characteristics. In August of 2020, EPA initiated a pilot project to convey and further assess low-cost sensor data. The data can be found at: We do not incorporate low-cost sensors into our monitoring network but we continue to evaluate opportunities to use these sensors. See DEQ’s low-cost sensor bulletin for additional information.

DEQ's monitoring network measures the levels of five of the six ambient air criteria pollutants identified by the federal Clean Air Act. The following are criteria pollutants:

  • Particulate matter (PM10 = particulate matter less than or equal to 10 microns in diameter; PM2.5 = particulate matter less than or equal to 2.5 microns in diameter)
  • Carbon monoxide
  • Nitrogen dioxide
  • Sulfur dioxide
  • Ozone
  • Lead (Airborne lead is no longer considered a major health threat in most of the United States. With the phase-out of leaded gasoline and closure of the Bunker Hill Mine, DEQ no longer monitors airborne lead levels.)

Data are used to achieve the following:

  • Define the nature and severity of pollution in Idaho
  • Determine which areas of Idaho are meeting the air quality standards
  • Identify pollution trends in the state
  • Support smoke dispersion forecasts for agricultural burning and prescribed fire programs
  • Reconcile air quality models and emission inventories

To provide a quantifiable means to measure air quality, EPA's Office of Air Planning and Standards, has established standards for the six criteria pollutants referenced above. For each criteria pollutant, the standard includes a maximum concentration above which adverse effects on human health may occur. These threshold concentrations are called the National Ambient Air Quality Standards (NAAQS).

There are two types of standards: primary and secondary. Primary standards set limits to protect public health, including the health of sensitive populations, such as asthmatics, children, and the elderly. Secondary standards set limits to protect public welfare, including protection against decreased visibility, damage to animals, vegetation, and buildings. Idaho has adopted the federal air quality standards in the Rules for the Control of Air Pollution in Idaho (IDAPA–587).

Air Quality Monitoring Data Summaries

Each year DEQ issues an annual report to inform the public of air quality throughout Idaho. The report summarizes regional air quality while presenting air monitoring results for the six criteria air pollutants.

Quality Assurance

To ensure that ambient and meteorological data collected by Idaho's air monitoring network meet or exceed required standards, DEQ developed the Idaho Quality Assurance Manual, Ambient Methods, in 1987. The manual prescribes detailed operational procedures for sampling, analyzing, and reporting air pollution and meteorological conditions. The manual is reviewed annually and revised as needed, subject to approval by EPA. The latest revision to this base document is The State of Idaho Ambient Air Quality Monitoring Program Quality Assurance Project Plan.

Air Quality Monitoring Network Reviews

Each year DEQ develops a report on whether the monitoring network is achieving its objectives and identifying needed modifications. The report documents changes made to the monitoring network since the last review and proposed changes for the next year. The plan is submitted to EPA annually by July 1.

In 2006, EPA initiated a new requirement for monitoring agencies to develop a "5-year Ambient Monitoring Network Assessment." It is a comprehensive and detailed analysis of DEQ's network and explains/reconciles the rationale for choosing monitoring sites based upon a variety of factors and projections (e.g., emissions, population, and meteorology). DEQ submitted its first 5-year assessment to EPA in 2010.

Staff Contacts

Air Quality Monitoring Supervisor
Ben Seely
DEQ State Office
Air Quality Division
1410 N. Hilton
Boise, ID 83706
(208) 373-0454

Related Pages

Real Time Air Monitoring

Daily Air Quality Reports and Forecasts