Introdução: O ruído de impacto é caracterizado por apresentar picos de energia acústica de duração inferior a um segundo, em intervalos superiores a um segundo. Objetivo: Quantificar os níveis de ruído de impacto a que o policial militar fica exposto durante atividades de tiro com armas de fogo e analisar a atenuação do protetor auricular utilizado. Método: As medições foram realizadas no estande de tiros de um Batalhão da Polícia Militar. Para a medição dos níveis de pressão sonora foi utilizado um audiodosímetro modelo SV 102 (Svantek). Foram utilizados dois microfones simultaneamente: um externo e outro tipo inserção, e a arma utilizada foi a pistola calibre 40, da marca Taurus®. Resultados: Os valores obtidos no microfone externo foram de 146 dBC (pico) e ruído máximo de 129,4 dBC (fast). Os resultados obtidos no microfone de inserção foram de 138,7 dBC (pico) e ruído máximo de 121,6 dBC (fast). Conclusão: Nossos achados evidenciaram elevados níveis de pressão sonora no estande de tiros, que ultrapassaram os limites máximos recomendados (120 dBC), mesmo em medição com microfone de inserção. Portanto, alternativas para melhorar o desempenho da proteção auditiva devem ser consideradas pela equipe de segurança da corporação.

Introduction: Impact noise is characterized by acoustic energy peaks that last less than a second, at intervals of more than 1 s. Objective: To quantify the levels of impact noise to which police officers are exposed during activities at the shooting range and to evaluate the attenuation of the hearing protector. Methods: Measurements were performed in the shooting range of a military police department. An SV 102 audiodosimeter (Svantek) was used to measure sound pressure levels. Two microphones were used simultaneously: one external and one insertion type; the firearm used was a 0.40 Taurus® rimless pistol. Results: The values obtained with the external microphone were 146 dBC (peak), and a maximum sound level of 129.4 dBC (fast). The results obtained with the insertion microphone were 138.7dBC (peak), and a maximum sound level of 121.6 dBC (fast). Conclusion: The findings showed high levels of sound pressure in the shooting range, which exceeded the maximum recommended noise (120 dBC), even when measured through the insertion microphone. Therefore, alternatives to improve the performance of hearing protection should be considered.

OBJETIVO: analisar os níveis de ruídos emitidos por brinquedos nacionalmente comercializados, utilizados por crianças de 1 a 5 anos; comparar os valores entre os brinquedos com e sem selo do Inmetro (Instituto Nacional de Metrologia, Normalização e Qualidade Industrial) e analisar o espectro acústico dos brinquedos, com o intuito de identificar a área da cóclea que pode ser mais afetada por esses ruídos. MÉTODO: as medições foram realizadas em 20 brinquedos sonoros (10 com o selo do Inmetro e 10 sem o selo) com o uso do decibelímetro digital em sala acusticamente tratada, e a análise dos sons emitidos pelos brinquedos foi realizada por meio do programa Praat. RESULTADOS: a intensidade do ruído dos brinquedos com o selo do Inmetro posicionados a 2,5 cm do equipamento variou de 61,50 a 91,55 dB(A) e 69,75 a 95,05 dB(C) e a referente à distância de 25 cm variou entre 58,30 a 79,85 dB(A) e 62,50 a 83,65 dB(C). A intensidade do ruído dos brinquedos sem o selo do Inmetro a 2,5 cm variou entre 67,45 a 94,30 dB(A) e 65,4 a 99,50 dB(C) e na distância de 25 cm registrou desde 61,30 a 87,45 dB(A) e 63,75 a 97,60 dB(C), portanto os achados demonstraram que existem brinquedos ruidosos que ultrapassam os valores recomendados pela legislação vigente em ambos os grupos, com e sem selo do Inmetro. CONCLUSÃO: os brinquedos sem o selo do Inmetro apresentaram valores de intensidade significantemente maior em relação ao outro grupo, oferecendo maior risco à saúde auditiva das crianças.

PURPOSE: to analyze the levels of noise emitted by nationally-sold toys for use by children from 1 to 5 year old; to compare the values among the toys with and without the seal of Inmetro (National Institute of Metrology, Standardization and Industrial Quality) and to analyze the sound spectrum of toys, in order to identify the area of the cochlea that may be more affected by these noises. METHOD: measurements were performed on 20 sound toys (10 with the seal of the Inmetro and 10 without the seal) with the use of digital sound level meter in an acoustically treated room, and the sound analysis was performed using the Praat program. RESULTS: toys placed at 2.5 cm from the equipment with the seal of the Inmetro had an intensity ranging from 61.50 to 91.55 dB (A) and from 69.75 to 95.05 dB (C), positioned at 25 cm ranged from 58.3 to 79.85 dB (A) and from 62.50 to 83.65 dB (C). The results of the toys without warranty stamps placed at 2.5 cm ranged from 67.45 to 94.30 dB (A) and 65.4 to 99.50 dB (C) and the distance of 25 cm recorded from 61. 30 to 87.45 dB (A) and 63.75 to 97.60 dB (C), so that the findings demonstrated that there are noisy toys that go beyond the values recommended by the current legislation in both groups, with and without warranty stamps . CONCLUSION: the toys without the seal of Inmetro showed intensities values significantly higher than the other group, offering more risk to the children’s hearing health.

AIM: To review the literature about the effects of environmental noise on the hearing ability of firefighters. METHOD: The PubMed and Scielo databases were searched and studies from 2002 to 2012 that included the keywords firefighters, noise, and hearing loss were identified. Initially, 24 studies were selected, but only 10 met the inclusion criteria of investigating the effects of occupational noise on firefighters. RESULTS: Only 2 (20%) studies quantified levels of sound pressure and performed audiological tests to identify associations with noise intensity and 3 (30%) questionnaire-based studies reported that these professionals are more susceptible to hearing loss. Four (50%) studies found that noise exposure damages the auditory system in this population. DISCUSSION: These findings indicate that there is a necessity for preventive measures to be adopted by this population since it is considered to be at risk. CONCLUSION: In recent years, there have been few studies of firefighters' exposure to occupational noise, but our findings show the importance of new studies that include proper means of quantifying their exposure to noise in different work environments, in order to identify possible adverse conditions as well as to aid in the diagnosis of hearing loss.