Both regulatory and recommended limits for noise exposure were developed from hearing and noise data obtained in occupational settings, where exposure to loud sounds is frequent and can last for decades.[1][9] Although specific regulations vary across the world, most workplace best practices consider 85 decibels (dB A-weighted) averaged over eight hours per day as the highest safe exposure level. Using an exchange rate, typically 3 dB, allowable listening time is halved as the sound level increases by the selected rate.