An approach to occupational noise assessment frequency band

This article discusses the improvement of occupational noise assessments methodologies in Brazil, which currently rely on measuring overall noise levels to determine hearing protection occupational requirements. The proposal introduces a new perspective by considering the diverse sound sources present in workstations, which often exhibit a wide range of frequency variations in their spectral compositions. This shift in approach is particularly relevant because hearing loss assessments, as mandated by occupational health legislation, require the evaluation of detection thresholds at specific frequencies (500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz for air conduction; 500, 1000, 2000, 3000, and 4000 Hz for bone conduction). The proposed methodology goes beyond measuring overall sound pressure levels by also analyzing the frequency spectrum to identify pressure levels across different bands. This allows occupational hygienists to pinpoint specific sound sources that may contribute to hearing losses detected by health professionals (physicians or speech therapists). The first results indicate that the curve of some hearing protectors no longer covers some frequencies. Difficulties were found to define a methodology for environmental and occupational measurements. By integrating spectral analysis, this approach fosters better correlation between occupational noise sources and diagnosed hearing impairments, enhancing prevention strategies.