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85 is the average, it routinely goes above 300 and is above 170 right now; in winter we can get to 600, 700, even 800; going outside is painful in thst case. If the 2.5PM rating gets over 100 in the states, it is a huge scandal.

Coal is used for heating in winter, all heating plants are owned by the city. That is why the air gets immediately cleaner when the heating goes off (last week or so). It's complicated.

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A bit more info, here's the EPA's PM2.5 scale:

http://www.airnow.gov/index.cfm?action=pubs.aqguidepart

Above 100 is unhealthy for sensitive groups, above 150 is unhealthy for everyone, above 200 is very unhealthy, and above 300 is dangerous.

Here's China's current PM2.5 as relayed by the US Embassy (To prevent official tampering):

http://aqicn.org/city/beijing/us-embassy/m/

The average over the last 5 days is 150, the peak over the past 5 days was 201.

This week has been sucky, I expected better. Anyways, the win will pick up today and we'll have a bit of clean air for a few hours, at least.

Never mind. Dust storm, pm2.5 is low, but the pm10 rating just shot up to 900! Shit.

Worth noting that the AQI scale you are citing (100, 150, etc.) and the ug/m3 used in the article are different numbers. AQI of 85 is not so bad. 85 ug/m3 isn't good.

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