Abstract
According to ANSI standard S12.42 new aspects have to be considered when measuring the Insertion Loss of Hearing Protectors at an Acoustic Test Fixture. First, the ear simulator has to be able to measure up to 170 dB SPL, so a 1/4 in. microphone is needed. The ear canal extension is also longer than the standard extension known from KEMAR and is fitted with flesh simulation. The circumaural pinna has a larger diameter to ensure a perfect seal for all kinds of hearing protection devices (HPD). Furthermore, the total system consisting of ear simulator, ear canal extension, and pinna is heated to body temperature. All the effects of these new aspects have been measured to assess their influence compared to previous ATF types like the ISO 4869-3.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
