JBeale created a quick solution to monitoring air quality as the 2020 Oregon wildfires raged, eventually burning over 1,000,000 acres.

Tracking indoor CO2 PPM levels emerged early in the pandemic as a way to measure one’s local environment for stale air and the increased likelihood of disease transmission. But measurements such as CO2 levels and the Air Quality Index (AQI) have also entered the public consciousness due to frequent large wildfires in recent years, and the propensity for their effects to spread well beyond their origins.

The system consists of a Teensy 3.1 connected to a Plantower PMS5003 laser particle sensor, with a small OLED display presenting time series data from the sensor. Initial test measurements showed particle pollution levels of 3-5 PM2.5, but the wildfires brought readings to 90 indoors and 380 outdoors. The resulting thread also brought out AQM projects from other forum members, as well as JBeale’s own Teensy 4.1-based evolution that uses the built-in mSD for data logging. The original sketch is available on GitHub as part of JBeale’s DataAcq collection of data acquisition tools.