A class of count-and threshold mechanisms, collectively dubbed α-count, able to discriminate between transient faults and intermittent faults in computing systems is presented. Transient faults discrimination has long been pursued in commercial systems: threshold-based techniques have been practiced for several years for this purpose. The present work aims to contribute to the usefulness of count-andthreshold schemes, through analysis of the behaviour and exploration of the effects on the system. A mathematically defined structure simple enough to be analysed by means of standard tools is adopted. α-count is equipped with internal parameters, designed to be tuned to suit environmental variables (such as transient fault rate, intermittent fault occurrence patterns). Extensive behaviour analysis for two embodiments of the scheme, both under the usual assumption of exponentially distributed fault rates and with more realistic fault patterns is carried out.