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Bystander impulse noise exposure from small-caliber weapons: how close is too close?

Murphy WJ; Flamme GA; Zechmann EL; Dektas C; Meinke DK; Stewart M; Lankford J; Finan DS; Collins S
Update: The Newsletter of the Council for Accreditation in Occupational Hearing Conservation 2013 Mar; 25(1):1,3
BANG, BOOM, BOOM, BOOM! Gun users have felt the powerful impact of that noise in their own ears, but what is its impact on the ears of people nearby? And what happens when several guns are shot at the same time? Hunters, sport shooters, soldiers, and police officers often fire their guns singly and in groups. Most shooters know that the noise from their own guns can damage their hearing, but they might not realize the hazard posed by noise from other guns. Bystanders also might not realize that their hearing is at risk if they are positioned too close to the person shooting. Researchers at the National Institute for Occupational Safety and Health (NIOSH) and affiliated with the National Hearing Conservation Association decided to work together on this issue. They set up an outdoor range to measure the noise impact (or exposure) from commonly available guns. Eighteen microphones capable of measuring high-level sounds were placed around a single shooter, at distances up to 6 meters, to measure the gunfire. The shooter fired 54 different guns (pistols, shotguns, and rifles) over a flat, grassy field. First, researchers used the measurements to determine how far away bystanders must be to keep their hearing safe. This minimum safe distance, called the foul line, was determined for each gun fired. Then the researchers estimated the effects of more than one shooter along a firing line. They combined the data from the single shooter to predict the sound exposure from multiple (2 to 16) shooters, positioned one-half to 2 meters apart, firing the same weapon.
Gunpowder; Noise; Noise-exposure; Noise-levels; Hearing-loss; Hearing; Hearing-disorders; Hearing-level; Risk-factors; Humans; Men; Women; Sound; Exposure-levels; Impulse-noise
William J. Murphy, Hearing Loss Prevention Team, National Institute for Occupational Safety and Health, 4676 Columbia Parkway, Mailstop C-27, Cincinnati OH 45226-1998
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Construction; Manufacturing
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Update: The Newsletter of the Council for Accreditation in Occupational Hearing Conservation
Page last reviewed: May 11, 2023
Content source: National Institute for Occupational Safety and Health Education and Information Division