Sistema IoT para monitoramento da qualidade do ar de ambientes indoor dos laboratórios de eletrônica da Universidade Federal do Amazonas

Abstract

This work presents a mobile IoT system for indoor air quality monitoring in the electron- ics laboratories of the Federal University of Amazonas. The device, based on the ESP32 microcontroller, integrates sensors for temperature and relative humidity (AHT10), a gas sensor used as an indirect estimator of carbon dioxide concentration (MQ-135), and an optical particulate matter sensor (DSM501B). Readings are transmitted over Wi-Fi to the Firebase Realtime Database and consumed by an Android application that classifies conformity based on ABNT NBR 17037:2023. A single device was manually repositioned across the seven laboratories, totaling 79 samples. The results showed that air quality is not uniform among the environments: the occupied laboratory presented a CO2 estimate exceeding the Maximum Acceptable Value of 1120 ppm, while the unoccupied environments remained close to the external reference levels, indicating a direct influence of occupancy on the estimated CO2 concentration. It is concluded that the system is suitable as a support tool for indoor air quality management, aiding ventilation and occupancy decisions.