What is the difference between passive and active hearing protection?
So-called ‘passive’ hearing protection – like that provided by Phonak’s Serenity Classic and Serenity SP systems – provides a constant, unchanging level of sound dampening (‘attenuation’). This makes passive protection systems a great fit for people who work or play in continual loud noise. Some passive attenuation systems, such as Serenity SPC, are also available with built-in radio communication. In contrast, ‘active’ hearing protection systems (also referred to as intelligent or ‘dynamic’ systems), provide electronic level-dependent protection. When an active system’s built-in miniature microphones detect noise levels reaching dangerous levels – including very short ‘impulse’ noises such as gun shots or crashes – these sounds are instantaneously dampened to a comfortable, safe level. However, when sound levels decrease to safe levels, active systems detect this too and instantly reduce the attenuation provided, even amplifying some quieter sounds, to give the user full environmental
