OSHA currently enforces an eight-hour time-weight Average (TWA) PEL of 90dBA, and uses a 5dB exchange rate. NIOSH recommends an eight-hour TWA exposure limit of 85dBA and a 3dB exchange rate. The 85dBA limit and 3dB exchange rate is also used as a threshold limit value (TLV) by the American Conference of Governmental Industrial Hygienists (ACGIH) as well as many European countries. Discuss using a 5dB exchange exchange rate versus a 3dB exchange rate in protecting workers hearing. Make a case for the use of either the 90dBA PEL and 5dB exchange rate or the 85dB REL and a 3dB exchange rate?