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I aspire to have zero particulates in my home air, it takes some doing. Much of the particles are of human/industrial origin anyway. Exhaust and tire particulat

I aspire to have zero particulates in my home air, it takes some doing. Much of the particles are of human/industrial origin anyway. Exhaust and tire particulate and various broken down human built materials. Particulates seem to be the easiest to remove -- much easier than VOC's and other gases. My new furnace has a MERV 11 filter that I've been playing around with in recent days as we've had AQI close to 100. I have an air quality monitor (that measures PM1, PM2.5 and PM10) in the house, within about 20 minutes of turning on the furnace blower, AQI of 70 inside the house drops down to less than 10, and 20 minutes after that, it's down in the low single digits. I have a MERV 13 filter that I could put in the furnace, but I'm not sure I need it since the MERV 11 seems to handle it.

porknubbins 5y ago
Yeah I lived maybe 100 meters from a busy road so I bought an air cleaner out of concern, but also got an Arduino with a serial device monitoring PM 2.5. PM 2.5 was always low teens or single digits, until I blew out a match next to the device and it went to 100s but dipped very quickly, so I think particulates aren't the biggest concern in most houses, unless maybe they spend all day with the windows open.
- eurasiantiger 5y ago
  How do you know your measurements are accurate?
  - Johnny555 5y ago
    I tested my indoor sensor (Davis Airlink) by comparing to others in my neighborhood -- I set it up outside on the first bad air quality day we had and an hour later it was with 5 AQI points of the 4 PurpleAir sensors within a quarter mile. Certainly not professional level calibration, but shows that it's within the ballpark. Unfortunately I don't think there's an official EPA monitoring station within 10 miles so I can't really check it against a calibrated monitor.
  - porknubbins 5y ago
    Aside from trying to buy a commonly used reliable device, that what the match test was for. When my device was reading 12ppm pm2.5 and a blown out match made it read in the 100s clearly the device is working to some degree of accuracy. I could've checked it outside I guess but I think local air conditions would predominate over any official city average I could have compared it against.

porknubbins 5y ago

Yeah I lived maybe 100 meters from a busy road so I bought an air cleaner out of concern, but also got an Arduino with a serial device monitoring PM 2.5. PM 2.5 was always low teens or single digits, until I blew out a match next to the device and it went to 100s but dipped very quickly, so I think particulates aren't the biggest concern in most houses, unless maybe they spend all day with the windows open.

eurasiantiger 5y ago
How do you know your measurements are accurate?
- Johnny555 5y ago
  I tested my indoor sensor (Davis Airlink) by comparing to others in my neighborhood -- I set it up outside on the first bad air quality day we had and an hour later it was with 5 AQI points of the 4 PurpleAir sensors within a quarter mile. Certainly not professional level calibration, but shows that it's within the ballpark. Unfortunately I don't think there's an official EPA monitoring station within 10 miles so I can't really check it against a calibrated monitor.
- porknubbins 5y ago
  Aside from trying to buy a commonly used reliable device, that what the match test was for. When my device was reading 12ppm pm2.5 and a blown out match made it read in the 100s clearly the device is working to some degree of accuracy. I could've checked it outside I guess but I think local air conditions would predominate over any official city average I could have compared it against.