User:Mackenziequinn167/sandbox

OSHA
The current PEL for OSHA standards are based on a 5 decibel exchange rate. OSHA’s PEL for noise exposure is 90 decibels (dBA) for an 8-hour TWA. Levels of 90-140 dBA are included in the noise dose. PEL can also be expressed as 100 percent “dose” for noise exposure. When the noise exposure increases by 5 dB, the exposure time is cut in half. According to OSHA, a 95dBA TWA would be a 200 percent dose. PEL is exceeded when TWA > 90 dBA. OSHA requires feasible engineering OR administrative controls, and mandatory hearing protection when the PEL is exceeded.

MSHA
Like OSHA, Mine Safety and Health Administration(MSHA) also uses the same 5 decibel exchange rate and 90 dBA for an 8-hour TWA for their PEL. Once a miner's noise exposure exceeds the PEL, feasible engineering AND administrative controls must be in place to try to limit the noise exposure of the employees. If a mine operator uses administrative controls, procedures for such controls must be posted on the bulletin board and a copy must be supplied to all affected employees.

NIOSH
The National Institute for Occupational Safety and Health(NIOSH) Recommended Exposure Limit (REL) for noise exposure uses a 3 decibel exchange rate. The recommendation for occupational noise exposure is 85 decibles (dBA) for an 8-hour TWA. For every 3dB over 85, the exposure time is cut in half. NIOSH reports exposures above this level are considered hazardous. NIOSH uses a hierarchy of control to reduce or remove hazardous noise.