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I like PurpleAir's crowdsourced air quality map[1]. Their sensors are one of the few that get down to the .3 micrometer level.

[1]https://www.purpleair.com/map

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I agree! I love their open API, too!

I'm in the process of creating a 501c, and as part of my mission to raise awareness, I'm going to purchase 5-10 PurpleAir II and have them across Lake Michigan's entire shoreline. Or, that's part of my plan.

Ideally I'd run a more extensive sensor that tracks more than just PM, but I have a feeling pollution varies a lot in a small distance, we get lake effect weather, but what about people 5-10 miles south of me, do they have it better/worse, etc. I'd love to know those questions, and PurpleAir makes it semi affordable

The Purple Air network and their map is great. Each has two Plantower PMS5003 sensors for redundancy or accuracy. However, you can purchase the Plantower sensors yourself at about $15/unit, which could help with the costs when you're trying to roll out a lot of them.

If you used the Plantower PMS5003 sensor by itself how would you be able to distribute the data? PurpleAir has arrangement with government to have their data added to official measurements and can be seen on https://fire.airnow.gov

Purple Air already has pretty good coverage of Lake Michigan[1].

They also have good coverage in my area, but when wildfire smoke was bad in CA last year I spread out four PM2.5 sensors outside and two inside using Home Assistant/ESPHome. They respond to conditions very quickly, and I could see waves of smoke pass through.

Why does that matter? Keeping everything closed up and using an air purifier really improves the indoor air quality, but it also gets oppressive when you never exchange any fresh air. The nearest Purple Air sensor is 2000ft away on the other side of a hill. At times it might be an equivalent 80 AQI here and 200 AQI there or vice versa. It was convenient to know when opening a window to let out some stale air brought in less new smoke to have to filter.

A DIY approach isn't just cheaper, it allows the addition of other types of sensors like NO2, SO2 and ozone, and it makes fine-grained data collection affordable. Kingsloi expressed an interest in monitoring other pollutants in addition to PM2.5/PM10. In my particular case it is adding NDIR CO2 sensor inside.

All of these sensors have a limited life span. The $250 PurpleAir PA-II has a 1 year warranty. Even though it is likely to last a lot longer than that, it is a pretty large markup over $40 per setup, especially if Kingsloi's needs include other pollutant sensors. The Purple Air network is an advantage, but a nonprofit started by Kingsloi could partner with air quality organizations in Michigan or Illinois, too.

[1] https://www.purpleair.com/map?opt=1/m/i/mAQI/a10/cC0#6.34/43...

Is there something similar where you buy the separate parts yourself and put it together? 280 usd is quite steep.

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