So I'm in Paradise, CA right now packing to move.

--- Inside ---

PM1.0: 4 µg/㎥

PM2.5: 5 µg/㎥

PM10.0: 5 µg/㎥

^-- Dual MPR "2900" / MERV "14" filters 25x356x610mm (1x14x24") with fan on @ 50% duty cycle

--- Outside (as of writing) ---

Looks gray like "fog" during the day, but it's UFPs.

PM1.0: 31 µg/㎥

PM2.5: 57 µg/㎥

PM10.0: 75 µg/㎥

--- Outside (recorded on 28 Sep 2020, sky completely obscured dark as night and the sun red like blood) ---

PM1.0: 815 µg/㎥

PM2.5: 893 µg/㎥

PM10.0: 920 µg/㎥

Data collection method: 15 minute sliding-window avg

Data collection sensor: Plantower PMS5003 (same as on the PurpleAir PA-II)