What is Exchange Rate or (Doubling Rate)?
Exchange rate refers to how the sound energy is averaged over time. Using the decibel scales, every time the sound energy doubles, the measured level increases by 3dB. This is the 3dB exchange rate that most of the world uses. For every increase of 3dB in the time-weighted average the measured DOSE would double. For OSHA and MSHA measurements, the Exchange Rate is 5. Some organizations such as OSHA in the U.S. have argued that the human ear self compensates for changing noise levels and they felt that the 3dB exchange rate should be changed to more closely match the response of the human ear. OSHA currently uses a 5dB exchange rate, which would mean that the reported DOSE would double with every 5dB increase in the time-weighted average. The exchange rate affects the integrated reading LAVG, DOSE, and TWA but does not affect the instantaneous sound level.
