Smart electronic device for air quality and exposure risk assessment

This article reports on the measurement of air pollutants and assessment of health exposure risks in two reference hospitals in the city of Yaoundé, using a locally manufactured smart electronic device for the measurement of highly toxic air pollutants. This low-cost device is based on an Atmega328 microcontroller, toxic gas sensors (O₃, PM_2.5, CO, CO₂ and NO₂), temperature (T), relative humidity (RH) sensors, and XBee modules to establish the Internet of Things (IoT). In each of the two hospitals, 2 weeks of measurements conducted from October 15 to 30, 2023 at Biyem-assi Hospital and from September 1 to 15, 2023 at Central Hospital. The average values obtained were 0.96 ± 0.06 ppm and 0.37 ± 0.09 ppm for O₃, 39.66 ± 10 µg/m³ and 39.72 ± 10 µg/m³ for PM_2.5, 0.41 ± 0.01 ppm and 0.42 ± 0.02 ppm for CO, 316.55 ± 63 ppm and 305.84 ± 89 ppm for CO₂, and 0.43 ± 0.01 ppm and 0.45 ± 0,02 ppm for NO₂ in Biyem-assi and Central Hospitals, respectively. These values were used to assess the risk of exposure through the Air Quality Index (AQI) and the Air Quality Health Index (AQHI_2.5).