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Current Air Quality

Air Quality Index

Predominant Air Pollutant: Fine Particulate Matter (PM2.5)
Updated Hourly at 2024-12-04 9:35 pm
Good0 – 50
Moderate51 – 100
60
Unhealthy for Sensitive Groups101 – 150
Unhealthy151 – 200
Very Unhealthy201 – 300
Hazardous301 – 500

Jump to Air Quality Index Definitions

Air Quality Forecast

Today
Moderate
Tomorrow
Moderate
Forecast Discussion – The cloudy skies and seasonal temperatures will persist as high pressure remains over the region, with low clouds and a chance of patchy fog in some areas as the strong inversion layer traps air near the surface. Fine particulates (PM-2.5) will continue to accumulate during the overnight hours as calm conditions produce poor ventilation, which may keep air quality in the AQI-Moderate range most of the time on Tuesday, Wednesday, and Thursday with potential to briefly reach the upper limits of the AQI-Moderate range or higher at night. /MCKAY

Learn more about Particulate Matter (PM) and Ozone (O3).

Air Quality Map

Click on a monitoring site to access more data, including daily and five-day trends.

Notice: The Sprague & Haven monitoring site (at The Hive) is temporarily offline for repairs.

About the Air Quality Index (AQI)

The AQI is a tool for reporting how clean or polluted the air is and the potential health effects. An AQI greater than 100 means air quality is not within the health-based air quality standards established by the EPA.

The Current Air Quality reported at the top of this page, represents the predominant pollutant and its highest reading among the countywide monitoring sites. The map above provides AQI data at the individual monitoring sites.

The AQI is divided into these six categories:

  • GoodAir quality is considered satisfactory, and air pollution poses little or no risk. Numeric Value: 0-50
  • ModerateAir quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution. Numeric Value: 51-100
  • Unhealthy for Sensitive GroupsMembers of sensitive groups may experience health effects. The general public is not likely to be affected. Numeric Value: 101-150
  • UnhealthyEveryone may begin to experience health effects; members of sensitive groups may experience more serious health effects. Numeric Value: 151-200
  • Very UnhealthyHealth alert: everyone may experience more serious health effects. Numeric Value: 201-300
  • HazardousHealth warnings of emergency conditions. The entire population is more likely to be affected. Numeric Value: 301-500

Air Quality Monitoring & Forecasting FAQs

What does Current Air Quality represent?

The Current Air Quality represents the overall AQI for Spokane County. Is represents the highest reading of the predominant pollutant (the pollutant with the highest value) We only use data from our regulatory monitors for the overall AQI. We do not include sensor data in the overall AQI.

The air quality monitoring network measures concentrations of three air pollutants: PM10 (coarse + fine particles), PM2.5 (fine particles) and Ozone (measured May-Oct during ozone season.) The monitoring map (above) provides data for each monitoring site in Spokane County. You can view the current day trend, or you can view a 5-day trend for each site. Some sites measure multiple pollutants.

How is the AQI calculated for the Current Air Quality?

Each pollutant has its own health-based standard. For particulate matter, it is a 24-hour average, midnight-to-midnight. This means the official daily AQI is not known until the following day. A rolling 24-hour average report also isn’t very useful when conditions rapidly change, such as during a dust storm or wildfire. To address this, EPA developed the NowCast to report air quality that is near real-time (referred to as “Current Air Quality” reported at the top of this webpage.)

The NowCast calculation is designed to be responsive to rapidly changing air quality conditions.  More recent hourly air pollution readings (e.g., last three hours) are given greater weight in determining the NowCast index value when air quality is changing more rapidly, as may be the case when wildfire smoke affects air quality. 

Why don’t we provide a one-hour, stand-alone value? Because there is not a one hour health-based standard. For ozone, the standard is an eight-hour average, and for particle pollution it is a 24-hour standard. The NowCast is a very effective tool to report near real-time air quality that correlates to the health-based standards. Learn more about the AQI and NowCast calculations.

Why is the AQI updated only once an hour?

Each hour, readings from our air quality monitors are automatically uploaded to the statewide air quality monitoring telemetry system and then to EPA’s AirNow.gov.  Data goes through a quality check, and then at :35 past each hour, our website is updated with the most recent hour of data. So, the Current AQI updated at 1:35 pm is monitored data from Noon-1pm.  At 2:35 pm, the 1-2 pm data is reported.  The delay enables our system to ensure we are providing the best quality data. If a monitoring site has a malfunction, this potentially “bad data” can be removed from the reporting so that the AQI isn’t erroneously reported.

What does “Unhealthy for Sensitive Groups” mean?

If the AQI is over 100 then it is in the Unhealthy for Sensitive Groups/Orange range. This means the air quality is not meeting the federal, health-based air quality standard.

Inhaling smoke is not good for anyone, even healthy people. Most people are likely to have minor symptoms. Others are considered in the Sensitive Groups because they are more likely to have health problems from breathing smoke. They include:

  • Those with lung diseases such as asthma or chronic obstructive pulmonary disease (COPD), including bronchitis and emphysema.
  • Those with respiratory infections, such as pneumonia, acute bronchitis, bronchiolitis, colds, or flu.
  • Those with existing heart or circulatory problems, such as dysrhythmias, congestive heart failure, coronary artery disease, and angina.
  • Those with a prior history of heart attack or stroke.
  • Infants and children under 18 because their lungs and airways are still developing and they breathe more air per pound of body weight than adults.
  • Adults over age 65 because they are more likely to have unrecognized heart or lung diseases.
  • Pregnant women because both the mother and fetus are at increased risk of health effects.
  • Smokers because they are more likely to already have lower lung function and lung diseases.
  • People with low socioeconomic status because they are more likely to have higher exposures and less likely to have access to healthcare.

How does Spokane Clean Air measure and report air quality?

We operate a network of monitoring sites in Spokane County, each with sophisticated instrumentation that collects concentrations of air pollutants every hour, around the clock.  The pollution concentrations are submitted to the state department of Ecology and the US Environmental Protection Agency (EPA).  Cities across our country are required to monitor compliance with health-based air quality standards for specific pollutants commonly found in ambient air and that pose a risk to human health and the environment. In 2024, we added eleven sensors to our monitoring network.

Monitors vs Sensors: What’s the difference?

Monitors:
Air monitors are devices used to measure air quality which require extensive testing and maintenance to meet rigorous performance standards.

Sensors:
Air sensors are devices used to measure air quality which cost much less than traditional air monitors to acquire and maintain. They do not meet performance standards required of monitors used for regulatory decision-making.

How is the 2-day Air Quality Forecast developed?

The 2-day air quality forecast is prepared each morning and it posts to our website typically by 10:35 am. Our air quality forecaster uses several sources of data and information when developing the 2-day forecast, including:

  • The current air quality trends
  • Weather reports, trends and forecasts
  • Smoke and active fire maps and models (during wildfire season)
  • Satellite images
  • Conference calls with other air quality and weather agencies during widespread events such as wildfires and dust storms.

Why isn’t there an air monitoring station closer to my home?

There are specific ambient air quality monitoring protocols outlined by the EPA that air quality agencies must follow. These requirements ensure that a community’s ambient air quality is measured effectively to determine if air quality standards are being met.  Ambient air quality monitoring is done at the neighborhood scale (representative of neighbor air quality) and at the community scale. While air quality can vary somewhat neighborhood to neighborhood, locations are selected to represent air quality over broad areas. For example, there are two monitoring sites that represent neighborhood air quality and others that represent community air quality. The emphasis is on areas expected to have the worst pollution as well as to avoid redundancies among locations. To expand the availability of data, eleven sensors were added to our air monitoring network in 2024, thanks to funding from Ecology. Air sensors are devices used to measure air quality which cost much less than traditional air monitors to acquire and maintain. They do not meet performance standards required of monitors used for regulatory decision-making.

Why is the air quality reported at AirNow.gov different at times than what is reported at SpokaneCleanAir.org?

AirNow.gov and Spokane Clean Air report the same air quality data which come from the regulatory monitors in Spokane County. For short periods of time, the websites report different values only because the two websites update at slightly different times.

Where can I access past air quality data reports?

Each month we provide a report of the previous month’s air quality data and post it here. The report provide the daily AQI and related concentration for each pollutant.

What are personal air sensors?

Personal air sensors are lower in cost, portable and easier to operate than regulatory-grade monitors. Their popularity is gaining across the United States and there are many studies underway to provide the latest science on their performance, operation, and best practices.

We are pleased to be partnering with local libraries and schools to provide air quality sensor programs. Learn more.

Visit EPA’s air sensor webpage for addition information. Below are links to three short videos on YouTube that help explain personal air sensor data interpretation:
Air Sensors: Regulatory Data and Sensor Data Quality

Air Sensors: Measurements and Your Health

Air Sensors: Sources of Air Quality Information

Why doesn’t data from my PurpleAir sensor align with what Spokane Clean Air is reporting?

PurpleAir data can report in different time increments, whereas regulatory monitors capture hourly data. This is why it is important to look at the data details. Here are some tips:

If you are looking at the Purpleair.com/map and want to compare Purple Air sensor data with regulatory, stationary monitoring site data, an equation has been developed by agencies, including EPA, that helps corrects the PurpleAir data. When looking at the PurpleAir map, in the lower left corner there is a box where you can select “Conversion” then select “US EPA” and then “one hour average graphs” to see the most comparable data to what is reported at SpokaneCleanAir.org and AirNow.gov and which corresponds to health-based air quality standards.