The purpose of obtaining this survey is to evaluate the hazardous levels of noise at your facility which are at or above OSHA’s Action Level (85 dB TWA 8 Hours).Federal noise regulations (OSHA and MSHA) require the evaluation of potential noise hazards in the workplace every two years or sooner if changes take place such as addition of new equipment, building modifications, or a change in the duration of exposures due to changes in work hours.