Tuesday, November 20, 2018

California fires + Air Quality + Ada + Bluepill + PMS7003

Camp fire

The Camp fire has had a big effect on the Air Quality Index (AQI) in the Bay Area over the past week or so. AQI is typically measured as an entry in one of 7 bands:

To compute the AQI (typically cited from the PM2.5 #) a formula is used. See the wiki page above.

The PM2.5# is in µg/mfortunately there is a Chinese sensor, the PMS7003 that can provide PM1, PM2.5 and PM10 in those units:

So we have a sensor, we already have a Bluepill running Ada with an SPI screen to display the results. 

The sensor is a $20 eBay purchase. Bluepills are < $2 as documented on this blog, screen is a little over $3. So for $25 or so you can build your own AQI meter.

Code is in: 


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