Low cost and portable electronic system based on electrochemical and pm sensors for the measurement of air quality monitoring

A portable, low-cost system for air quality measurement is presented in this communication. For the measurement of the main pollutants both gaseous (NO₂, NO, O₃, CO) and solid (PM₁₀ and PM_2.5), electrochemical and particulate matter (PM) sensors are used, all from Alphasense. The device also features measurement of meteorological data such as temperature and humidity. In addition, different communication modules (Bluetooth and ethernet among others) and storage of acquired data are included. The control core of the system is a low power microcontroller from the manufacturer ST (STM32L476), and the whole device is powered through a 230V AC socket. Air sampling is done actively, and therefore the equipment includes a pump. The complete system has been tested in real conditions during two months next to the fixed reference station located in Badajoz, Spain. Its general operation has been successful, with strong correlation results, although the calibration of the electrochemical sensors should be modified in future work to improve its performance, especially in environments with low concentrations of pollution.