Background: The aim of the study was to assess the influence of short-term impulse noise on the size of temporary threshold shift in soldiers using hearing protectors during exposure.
Material and methods: The study covered 80 subjects with normal tympanic membrane and thresholds measured by pure tone audiometry lower than 20 dB. There were two groups: I--composed of 40 soldiers protected during shooting and II--comprised 40 young males which did not shoot (controls). Transient evoked otoacoustic emissions were performed by an ILO 292 Echoport Otodynamics device 3-5 min before shooting and 2 min, 1, 2 and 3 h after shooting.
Results: The results showed that post-exposure changes in soldiers who used ear-muffs were not significant.
Conclusion: The use of hearing protectors is strongly recommended because most of them seem to sufficiently attenuate impulse noise from firearms.