Subject classification: 79.75.þg; S10On the basis of classification of exoelectron emission (EE) mechanisms we have proposed some experimental criteria for distinguishing these mechanisms: Bulk-surface criteria and the photon and low-energy electron excitation criterion. To illustrate the application of these criteria we have measured the influence of the precipation procedure on thermostimulated EE (TSEE) of CaSO 4 : Mn and the dependence of the TSEE and photostimulated EE (PSEE) intensity of CaSO 4 and MgO on exciting electron and photon energy.