Oregon Air Quality Index Hits 700 And Beyond - 301 And Higher Considered "Hazardous"

As wildfires rage across much of California and the Pacific Northwest, smoke continues to clog the air and tinge the sky with apocalyptic reds and oranges. In some parts of Oregon this week, the air got so smoky that it maxed out the scale used by the Environmental Protection Agency (EPA) to measure hazardous air quality.

The EPA’s Air Quality Index (AQI) measures five types of air pollution on a scale of one to 500. “Healthy” air gets a rating between 0 and 50. Things start getting dangerous in the mid-100s, especially for sensitive groups like those with a heart or lung condition. And an AQI reading of 301 or greater is considered “hazardous,” causing the EPA to declare “emergency conditions” for those who are exposed for 24 hours or more.

On Wednesday afternoon and Thursday morning, the area around Eugene, Oregon, clocked AQI values well into the 700 range on the real-time air-quality monitoring site PurpleAir, greatly exceeding the scale’s maximum value of 500.

The problem is all the fine particulate matter that’s being generated by the West Coast wildfires. These particles get suspended in the air and can cause health problems when they’re inhaled. The smallest particles — known as PM 2.5 — are especially concerning, since the body can’t filter them out. “The 2.5 will just cruise past everything in your nose,” said Amy MacPherson, a public information officer for the California Air Resources Board. These particles can get lodged in people’s lungs, she explained, “and if they’re even smaller than that they can get into your bloodstream.” Health effects include an increased chance of cardiac arrhythmias, asthma attacks, and heart attacks.

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https://grist.org/climate/oregons-air-quality-is-so-far-beyond-hazardous-that-no-one-knows-what-it-means-for-health/