Frequently Asked Questions
What's the easiest way for me to see local air quality conditions?
Current conditions are shown on the map with colored dots representing monitoring locations and the current air quality conditions. In many cases, monitors closest to you will give you an indication of the local air quality, though variations may exist due to topographical and meteorological influences (e.g., mountains, wind, etc.). Click on a dot for detailed information on the pollutants measured, current concentrations, and monitor station information.
Air Quality Forecast Information
DEQ provides air quality forecasts throughout the state that incorporate current monitoring data and anticipated pollutant
concentrations. Our regional offices issue daily forecasts on our
Air Quality Forecasts page and on
EPA’s AirNow pages.
Historical data are available under the Reports menu. The most commonly used reports are the “Station Report” (single air monitor) or the “Multiple Stations Report” (multiple instruments). Select from a variety of criteria to look at the data in different ways. Refer to the Information About Reports page for more information on specific reports.
Air quality monitors are expensive and DEQ has limited resources for ambient air monitoring. Monitoring requirements are often triggered by population and pollution concentration thresholds. A handful of monitors are operated in areas where significant impacts are reasonably expected from wildfires, prescribed burning, or other local issues.
The “last update” date and time shows the latest available data for a particular monitoring station. Data is updated hourly using the information collected during the last hour. This provides nearly real-time air quality information. The time listed for monitoring data is local standard time and monitors operate in the Pacific Time Zone or Mountain Time Zone depending on location. Although the data are current, daylight savings time creates a one-hour difference between “local time” and that shown in the system. There are two ways to show the same data: “hour ending” and “hour beginning.” For example, an average concentration measurement obtained between 8 and 9 a.m. will be labeled 9 a.m. in “hour ending” format and 8 a.m. in “hour beginning” format. DEQ’s real-time map uses “hour ending” for displaying the latest data.
While every attempt is made to ensure that only valid data are displayed, the data comes directly from air monitors and are available for public use before all quality assurance reviews can be completed. Data can change any time up until it is certified as “final” with the EPA. For additional information about the data visit the Monitoring page.
What is the difference between the dot AQI I am seeing and an air quality forecast?
DEQ collects hourly air quality data and converts the weighted averages of these values into a real-time Air Quality Index (AQI) known as the NowCast and displays it on the map. An air quality forecast is a forecast of the AQI category that incorporates not only the calculated AQI but an evaluation of trends in the monitoring data and meteorological conditions to determine how the air quality conditions might change with time.
If multiple pollutants are measured at a single site, which one is responsible for the AQI on the dot?
The highest of these AQI values is what determines the reported AQI for the site and is what will show up on the map dot.
I used to see dots in certain areas of the state but no longer do. Why?
DEQ has a number of monitors in its network that are used seasonally to asses the impact of crop residue burning impacts and to make decisions on whether or not burning is appropriate for a given day. These monitors are usually active from April through October and will only be available for reporting on the map while in operation. In addition, as mentioned previously, common causes of missing data can include routine maintenance, mechanical problems or disrupted communications. If it determined that a monitor may be offline for a significant amount of time, the dot may be removed from the map to reduce confusion for the public.
Why does the AQI on the DEQ map sometimes differ from the AirNow website?
Differences may exist between the DEQ map and AirNow webpage due to when each website is updated. The real-time air monitoring map displays the most current data available. The AirNow site collects data from multiple sources before updating their site, often in the second half of the hour. In addition, the AirNow webpage uses different QA/QC criteria to flag and invalidate data. As a result, there can be times, especially during wildfires, when the values might be removed from the AirNow dataset.
Why is data missing when I run a report?
There are a few possible reasons why data might be missing:
- Data is not available for the time specified in the report query
- It was determined to be invalid
- The data is older and has been archived
For additional questions or for access to archived data, contact DEQ:
DEQ State Office
1410 N. Hilton
Boise, ID 83706
(208) 373-0502 or (866) 790-4337