Existing OSHA requirements restrict worker exposure to a maximum of 90dBA for 8 hours. Local ordinances of codes may impose different standards and criteria. Engineering, and/or administrative noise control measures are required if the worker exposure exceeds 90 dBA. 

Engineering includes the application of silencers; administrative includes limiting exposure time. In part,  noise or continuous loud noise exposure above 90dBA can result in permanent hearing loss.

Noise levels above 80 dBA interfere with normal speech making communication difficult.

 

OSHA Requirements​

INDUSTRIAL SILENCERS