Influence of the COVID-19 pandemic on the external environmental noise of a public hospital in Sorocaba, Brazil

Abstract
This study aimed to evaluate environmental noise around a public hospital in the city of Sorocaba, Brazil, before and during the COVID-19 pandemic. The measurements were performed in triplicate, on weekdays, at three points around the hospital during the night, and followed the guidelines of the NBR 10151/2019 standard. At the same measurement points, the manual counting of light vehicles, heavy goods, and motorcycles was performed. The equipment used was the BK 2260 analyzer and the BK 4231 calibrator. For statistical analysis, data normality was verified through the Shapiro-Wilk test and, later, the differences in sound levels before and during the pandemic through the paired t-test. The correlation between sound levels and the number of vehicles was verified by Spearman's correlation. The level of significance adopted was α=0.05. There was a significant reduction in the movement of light and heavy vehicles during the pandemic and less reduction for motorcycles. It was found that P1 was the noisiest point and the one with the lowest variation in dB(A) during the pandemic, associated with higher speed and greater circulation of vehicles. Although there is a strong correlation between the number of vehicles and sound levels, statistically there was no significant difference. It is concluded with this work that there was a reduction in environmental noise around the hospital during the pandemic and that other factors should be taken into account, such as the speed of vehicles.