The efficiency of earmuffs against impulse noise from firearms.

Young men conscripted into the armed forces still run a risk of suffering hearing damage during their military service. This risk could be reduced by effective personal hearing protectors. The standard tests to determine the attenuation values of hearing protectors cannot be applied to high-intensity impulse noise from firearms, but the protectors should be evaluated under actual firing conditions. The attenuation values of the hearing protectors (earmuffs) most commonly used in the Finnish Army were tested for impulse noise from different weapons. The attenuation was found to be good for pistol shots, moderate for rifle shots and very poor for cannonfire. The tested earmuffs gave only minimal protection against low-frequency impulse energy.