The Attenuation of Hearing Protectors against High-level Shooting Impulses
نویسندگان
چکیده
The acoustical attenuation of five different hearing protectors were investigated using real impulses and miniature microphone technique in field conditions from a 23 mm antiaircraft cannon, from 122 mm howitzer and from an explosion of 1 kg of TNT. The measurements were carried out using voluntary military officers exposed to similar impulses in their work. The combination of earmuffs and earplugs proved to give the best attenuation. The attenuation of the earmuffs was related to the size of the cup. Light protectors gave practically no protection against the highest impulses from howitzer and TNT-blasts.
منابع مشابه
Actual Effectiveness of Hearing Protection in High Level Impulse Noise ( Reprint
Current exposure limits for high intensity impulse noise contain factors for hearing protection which are based on very limited data. Recent studies in the U.S. and in France have provided new insights into the protection afforded by hearing protective devices. For impulses with an Aduration of approximately 3.0 ms, protection was found to be adequate for peak pressures up to 190 dB SPL for 6 i...
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