Avaliação ambiental de uma escola municipal de Contagem/MG: uma análise por meio do nível da pressão sonora e da percepção de professores.

Sound comfort is presented as a public health issue by WHO (World Health Organization) being defined as the appropriate limits to preserve hearing health, respecting the environment and being able to make it acoustically possible to human beings, enabling them to perform their tasks with hearing preservation. This research aims to measure sound pressure levels and environmental perception of teachers at an elementary school unit from Contagem/MG (Brazil), observing, mainly, the vehicle traffic around the school and from the expressway Via Expressa at Contagem. It aimed to identify sound pressure levels recommended by current Brazilian legislation _ NBR 10152:2017 _ and check if the measured NPS were in accordance with these parameters. The measures occurred during 15 days, between 26/10 and 19/11/2020, in 10 different school places, every 15 minutes in the morning and the afternoon, totalizing 5000 measures. The results made possible to conclude that only 10% of all measures were in accordance with the aforementioned legislation, and the morning shift was the most harmed with high NPS. The afternoon shift presented better acoustic comfort compared to morning and the art room, the place with the greater number of measurements according to the adopted references, indicating school environments more appropriate to learning than others. The traffic light at Via Expressa is a positive factor in reducing NPS, as it guarantees vehicles stopped on the lane, near school, which contradicted initial hypothesis. The pandemic caused by SARS-CoV-2 virus positively contributed to the development of this research, since the measurements of sound pressure levels made are exclusively from the ambient noise of the analyzed school unit, as administrative employees, teachers and students weren’t at school during the measurement period. A virtual questionnaire was applied to teachers from the school unit, with a participation of 91%. They stated that they noticed the high levels of sound pressure, indicating that it harms the teaching-learning process, causing a decrease in concentration and attention of teachers and students. Vocal fatigue, ringing in the ear, headache and irritation were also mentioned by respondents as symptoms caused by high levels of sound pressure at school environment. Teachers from the morning period were more perceptible about these factors in comparison with the teachers from the afternoon period, confirming the measurements performed. In conclusion, teachers and students have a compromised health because of the high number of measurements above the limit pointed as indicated for humans at school environments, with vehicular traffic being observed as the main contributor to highest NPS measured.