Sennheiser HMEC 300, HMDC 322, HMEC 400 Valuable information on NoiseGard, The NoiseGard principle

Models: HMEC 306 HMEC 305-C HMEC 302 HMEC 305 HMEC 322 HMEC 400 HMDC 322 HMEC 300

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Valuable information on NoiseGard™

The NoiseGard™ principle

One of the greatest stress factors today is noise. Research has shown that noise affects the nervous system, and can cause tiredness, poor concentration, irritability and tension. Of even greater concern is the permanent damage to hearing that can result from noise at high levels.

This problem concerns pilots in particular. Cockpit noise amounts to about 80 dB(A) in jets and to 90 up to 97 dB(A) in turboprops. During takeoff and landing, the noise level is even higher. To be able to understand radio traffic in spite of the noisy environment, the ATC signal level must be set to at least 95 dB(A). Permanent hearing loss caused by the continuous noise in aircrafts is the reason why many pilots became prematurely disabled or lost their pilot´s license.

Circumaural communication headsets provide noise attenuating properties and are commonly used to address this problem. However, the noise attenuation of these headsets is uneven. High frequencies are reduced considerably, but low frequency wind and engine noise, the most prominent noise in many of today's aircrafts, is attenuated very little.

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Sennheiser HMEC 300, HMDC 322, HMEC 400, HMEC 322, HMEC 305 manual Valuable information on NoiseGard, The NoiseGard principle