A couple years ago I cobbled together a couple of air quality sensors to give my family and I a better idea of the state of the air in and outside our home, particularly during what seems to be becoming the annual fire season in the Pacific Northwest.
These were cobbled together devices mostly with parts I already had laying around, which worked fine, and continue to operate well, but as we approach another summer I was interested in putting together a couple additional sensors as well as improving the state of the hardware.
The sensor I’ve put together is based around an ESP32 reading data from a pair of Plantower PMS7003 particulate sensors, and a Bosch Sensortec BME280 Temperature, Pressure, and Humidity sensor. The data from all the sensors is then sent to my logging/graphing system via WiFi.
I took inspiration from the commercially available sensors from PurpleAir and designed it to fit within a 3″ PVC pipe cap, along with a 3D printed carrier, which provides for a nice outdoor enclosure that can be easily mounted in a variety of locations.
The 3D printed carrier has vent openings for the particulate sensors, and the temperature sensor extends below the main body to have the best exposure to the ambient temperature with minimized effects of internal heating, but still being sheltered under the cap.
I’m looking forward to getting a few of these deployed, and getting a better picture of the air quality in my area over the coming months.
Lastly, the project is open source and you can find all the resources on my GitHub repo.