[ol]
[li]The official sensors should report 24 hour average values as the health effects of PM are based on 24 hours.[/li]
[li]Also they measure outside AQ, not inside AQ .
That can be a big difference as in a lot of houses there is to much insulation and far to less ventilation.[/li][/ol]
Indoor AQ is 99% of the time worse then outside AQ.
Therefor you should not compare your inside measurements with the official ones.
Just keep the purpleair sensor outside and compare your AQ inside with the outside sensor.
On average, the difference is around 2-5 ug / m³.
For pm2.5 a difference of 2-5 ug / m³ is irrelevant in AQI values where the health effects differences are measured with steps of 30 or 100 ug / m³ .
I am curious what the difference will be when comparing inside pm-AQ with outside pm-AQ
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This week I am testing AQ scripts and there are 3 different sensors above my desk.
The real-time ug / m³ values always differ during the day.
The average value differences are less.
And the 24 hour average AQI is even more equal.
The difference between outside and inside measurements during the hot hours the last two days is larger caused by closing all windows and the automatic low speed of the ventilation.
During night-time the ventilation runs at full speed and the differences are very small.
