Healthy classroom: validation of a device for monitoring the air change rate

Sala de aula saudável: validação de dispositivo para monitoramento da taxa de renovação do ar

The increase in outdoor temperatures resulting from global warming, together the intensive use of HVAC systems without an adequate air change rate in schools have highlighted the need to monitor indoor air quality. This study presents the validation of a low-cost IoT (Internet of Things) device, named Healthy Classroom, developed to estimate the air change rate and indicate, in real-time, the need for corrective actions such as the controlled opening of doors and windows. The validation experiment was conducted through measurements of carbon dioxide (CO₂), air temperature, and relative humidity, which were compared with those obtained from a reference instrument. The results demonstrated a strong correlation between the measurements, confirming the reliability of the device as an accessible and applicable solution for continuous monitoring of indoor air quality in educational settings, supporting informed ventilation management and the promotion of health-promoting indoor environments.

Keywords
Indoor air quality; Air change rate; Air conditioning; Classroom; IoT