The recovery from impulse‐noise induced temporary threshold shift was systematically traced for individual rhesus monkeys and men. In addition to the well‐known logarithmic recovery, three other types of recovery were seen (diphasic, plateau, and rebound). A descriptive model is developed for the classification of these recovery functions. The model postulates the existence of two types of temporary threshold shift, process M and process S, both of which may be seen after impulse‐noise exposure.