There was a combustion event in the immediate vicinity of the SDS011 PM sensor today. PM10 spiked at over 1,050 ug/m³ and PM2.5 maxed out at around 650 ug/m³, putting both measurements comfortably (?) above the hazardous range on the AQI scale. Thankfully the event was short-lived. Also, given the concentrations of pollutants at the SDS011 location, by my calculations PM levels would have fallen below prevailing background levels by a distance of 30m from the flames

The fuel source was apparently paper; I trust someone was taking care of GDPR business and guarding other people's PII.

Following my recent observations about the reduction in peak readings on the weekly, monthly, and yearly graphs I shall be interested to track this data point through those graphs. At this moment it looks like the weekly chart has halved the peak values, and the peak on the monthly charts is at least an order of magnitude smaller than those on the daily graphs.