W W W . P S S O . D E
23
Information on Hearing Loss
More and more young people suffer from hearing loss of 25 decibel or more, mainly caused by loud music
from portable MP3 and CD players or discotheques. Everybody operating amplification systems should know
to what sound pressure levels he exposes his or the audience's hearing. As an average levels between 75
and 105 dB(A) in the discotheque or 95 and 115 dB(A) at a rock concert are reached. Individual peaks can
exceed the pain level at 130 dB(A). Such levels are typical for motor chainsaws or jack hammers.
Overview on the different noise levels
10 dB Heartbeat
80 dB Heavy traffic or telephone ringing
20 - 30 dB Whisper
90 dB Pneumatic drill
40 dB Average home
100 dB Power mower
50 dB Light traffic
120 dB Boom box in car
60 dB Normal conversation
130 dB Pain level
70 dB Vacuum cleaner
140 dB Jet plane 30 meters overhead
It is important to know that doubling the power increases the noise level by 3 dB. The human hearing does
only recognize a doubling of the sound level when the noise level is increased by 10 dB. Damaging the
hearing does not depend on the sound level but on the noise level and starts way before the pain level.
Many people deceive themselves by thinking that noise is something they can get accustomed to. It is
possible that a positive opinion of a certain noise can reduce the physiological reaction, but the slow impacts
on the inner hearing must not be neglected: over stimulation and continuous elimination of the Cortic organ's
hair cells.
The reason why some people have got accustomed to a certain noise level and are no longer disturbed is
that they have already suffered a hearing damage. This damage makes the insensitive to those frequencies
forming the loudest part of the noise. Getting accustomed to noise does not mean anything other than trying
to get along with the hearing loss in everyday life. The hearing loss itself cannot be healed; it can only be
compensated by hearing aids.
Subjectively, the hearing loss feels like dampened ears. This effect weakens with the time, but a loss in
hearing sensitivity often remains.
In order to relax the hearing sufficiently, the noise level should not exceed 70 dB(A) for 10 hours. Higher
noise levels during this relaxing period can prevent the relaxation and promote a permanent hearing damage
(Tinnitus) or hearing loss. Therefore: Whoever wants to maintain his hearing should use hearing protectors!