In our bid to protect your hearing, we made hearing protectors lighter, more comfortable and extremely efficient. However, we still had one major hurdle to overcome – offering too much protection! Before Active Listening, in noisy and dangerous environments the choice stood between risking your hearing or your physical safety. We needed to make sure that warning shouts, alarms, signals and noises associated with imminent danger could be heard while wearing your hearing protector. This is what our active listening function achieves – it listens out for your safety, amplifying some sounds while blocking harmful noise above 82dB.
The built-in electronic protection system (EPS) prevents noise levels beyond 82dB(A) reaching your ears through the speakers.
This graph shows how effectively the EPS system protects you from harmful noise through the active listening function. The function is level dependent, meaning that depending on the noise level outside the hearing protector, the active listening function will either amplify or decrease and limit the sound reproduced through the speakers. The graph show how active listening amplifies weak sounds and the EPS system limits high sound levels to a maximum of 82 dB(A) through the electronics.
When working in high activity dangerous areas you need to be able to hear warning signals. Choosing a hearing protector with the active listening function makes it possible to hear what happens around you while still wearing hearing protection. This function includes sensitive microphones, filters and a non-linear amplifier.
The active listening feature also helps you communicate. With microphones in each ear-cup and our Electronic Protection System (EPS) circuitry, low speech sounds are amplified and harmful noise over 82dB is blocked. This means that the risk for Noise Induced Hearing Loss (NIHL) can be removed.
Using passive hearing protectors when exposed to noise at 90 dBA means that speech recognition decreases from 70% to 25%. With active listening hearing protectors, the speech recognition is not decreased at all at the same level of decibel.
Scientific studies of speech intelligibility in noise have shown that passive hearing protectors decrease speech recognition drastically. The reason is that if you use a passive hearing protector, you automatically adjust your voice level using your hearing. If the protector worn by the listener has a high attenuation for that noise, your voice level will be lowered to a level that is hard for the listener to hear.
The safest option for clear communication in a noisy environment is to use electronic hearing protectors with sufficient attenuation, equipped with the active listening function. With this function, speech recognition easily reaches a level above 90%. You can speak at your normal dynamic range and get a clear sound quality. If you need to communicate frequently or at greater distances, two-way communication hearing protectors are recommended.
The effect of removing hearing protection in noise
Removing your hearing protection for as little as ten minutes a day in noisy environments means that the attenuation effect drops drastically. This is especially true at higher frequencies where the attenuation is optimal. If the protector is removed for just a short period of time in a noisy environment, the sound energy to the ear increases rapidly. Since the maximum attenuation of hearing protectors is concentrated at higher frequencies, the noise dose will be most affected in this range.
Read more about the risks of noise and how to use hearing protectors.