Hearing is considered to be endangered from a level of 80 dB(A) during an 8-hour working day. If the noise level is higher, exposure must be shorter. If the level is extremely high (above 130 dB (A)), any exposure, even of very short duration, is dangerous.
- Below 80 dB (A) prolonged exposure to noise can cause fatigue, stress, anxiety, attention disorders, sleep disorders, cardiovascular disorders, hypertension, etc. It can also disrupt communication, hinder concentration, distract attention etc, and lead to work accidents.
- Above 80 dB (A) noise can cause buzzing, ringing in the ears and temporary hearing loss. However this hearing fatigue is reversible and can disappear in a few days or weeks provided you are not exposed to noise again during this period.
- Above 140 dB (C) a sudden, very loud noise, e.g. an explosion, and can lead to sudden total or partial deafness which may or may not be reversible.
The Audiolyser® ADL20 tests hearing from -10dB to 120 dB.