Tell us we got something wrong
The most useful message you can send is a number that looks wrong. We publish a reading, the station behind it and the gap between that station and the local sensors — if any of those does not match what you can see, we want to know which page and what you observed. Corrections get a dated entry in the log.
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What we can and cannot answer
We can tell you how any number on this site was produced — which monitor, which hour, which correction formula, and what we do not know. That is the whole point of the method page, and anything it fails to explain is a gap worth reporting.
We cannot give medical advice. Every threshold on this site is attributed to the EPA or to a named community source, and none of it is a substitute for someone who knows your history. If you are asking whether it is safe for you specifically to go outside, that is a question for a clinician, not for us.