DeltaOHM HD2010UC/A, Руководство по эксплуатации

Страница: 126 / 162

HD2010UC/A
- 126 -
V4.1
Noises characterized by the presence of a pure tone, are more bothering, at the same level,
with respect to noises distributed over a wide interval of frequencies. The reason is to be found in
the sound energy “concentration” in the ear mechanics.
Usually, the sound level is not static, but it changes with time. If the variation is very rapid, the ear
cannot feel the real intensity. In case of sound pulses, we know that the ear has a reduced perception
already for durations lower than 70 ms. For this reason, noises with an impulsive feature are usually
considered, at the same level, more dangerous.