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Because You Asked: Should I Watch the 24-Hour Average or One-Hour Average On The Air Quality Index?

We’ve been steering a lot of folks to the Oregon Department of Environmental Quality’s Air Quality Index lately. The color-coded tool looks like this:

OK, sadly, this year it has had a lot more red dots representing air quality in the unhealthy range. Anyway, here’s how you use the AQI: Simply click on a dot on the map and it will tell you which station you’re viewing and what the most current air quality readings are. It will show one-hour and 24-hour readings for particulate matter, the key ingredient in wildfire smoke that can cause health effects.

A blog commenter recently asked which one to use so we checked in with DEQ’s Air Quality Monitoring Section.

Here’s what they had to say:

The one-hour average is meant to assess immediate exposure and the 24-hour average is meant to assess more long-term exposure at lower levels. Both can affect your health, particularly if you have heart disease, an ongoing lung condition including asthma, if you’re over age 65 or if you’re a small child.  You can use these measurements for different purposes. For example, you can use the one-hour average to watch for periods of improved air quality, when you can open up your house and “air things out.” That way, you can start with cleaner air if heavy smoke returns. If you are sensitive to smoke effects and are deciding whether or not to work outside all day, you may want to use the 24-hour average, then use the one-hour average to pick the best time to go out for any unavoidable outside errands.

With the start of school around the corner, we know a lot of you are looking at the forecast and trying to determine whether to hold practices or games. The Oregon Health Authority has a great fact sheet you should check out called Public Health Guidance for School Activities during Wildfire Events.

If you have a question for us, leave a comment. We’ve appreciated all the feedback this wildfire season.