Acoustic trauma caused by firearms

Background: Acoustic trauma caused by firearms has been well known for years. Surprisingly, how to prevent this harmful event is unfamiliar to the policemen. Methods: Twenty policemen were subjected to conventional and ultrahigh frequency audiometries, before and after shooting with submachine gun and rifle. Results: In conventional audiometry, 6 kHz and 8 kHz were the frequencies that most often influenced by gunfire. In the ultrahigh frequency audiometry, more than 50% of the ears had abnormal hearing in every frequency. Conclusion: It is recommended that the policemen should use ear plugs as well as ear muffs during shooting.