Microsonic offers custom Sound Defenders, molded from ear impressions made by an industrial hygienist, audiologist or hearing aid dispenser. They are available in Synth-a-Flex (vinyl), M-2000 (soft silicone) or Pass Guard (soft silicone), and can be ordered as solid plugs or with Double-Damped vents for differing requirements. Easy-to-insert canal-shell models are also available. The information that follows includes the attenuation data and noise reduction ratings (NRRs) of tested products. Attenuation tests have been performed according to the American National Standards Institute (ANSI) Specifications S3.19-1974.Notice that fairly predictable control over the level of attenuation of low frequencies can be obtained through the use of various damper values. Dampers used in pairs offers smooth curves and controlled attenuation well into the mid-frequencies.
Custom hearing protection offers no electronic sound dampening technology, and provides sound attenuation in the range of 20-30 dB across most of the hearing spectrum. Pass Guard is our new line of hearing protection. We have achieved an un-vented NRR of 40dB which is almost a 20 dB increase in passive protection between 125-800Hz over the traditional materials. Mean frequency attenuation values have increased upwards of 62% between 1000-8000Hz.