Pressure Measurements in the External Auditory Canal of a Human Head Model Exposed to Air Shock Waves

摘要

The head of an anthropomorphic dummy for blast research was used for estimating risk of damage to the eardrum in exposure to air shock waves. The head, originally made for crash tests, was modified and provided with simplified models of the external ear. Transducers were used to record pressure at the entrance and the site of the tympanic membrane. The head was exposed in an open-ended shock tube to overpressures of short duration and maximal overpressures of 50 and 190 kPa. The main purpose of the investigation was to compare the protective effects of ear muffs and ear plugs at pressure levels exceeding some 50kPa. Results indicate that the head model can be used for risk assessments, and that ear plugs are to be preferred to ear muffs for preventing rupture of the eardrum, especially at higher pressure levels than 50 kPa.