A power law approach as used by Fulop for the treatment of impact ionization and breakdown in abrupt silicon P-N junctions [Fulop W. Calculation of avalanche breakdown voltages of silicon P-N junctions. Solid-State Electron. 1967;10:39-43] is developed in this paper to provide simple-to-use equations for the quantitative evaluation of cosmic ray related phenomena in high voltage power devices. Being empirical in nature, such approaches have no physical background and only serve the purpose of generating a simple and compact mathematical framework. The resulting compact model allows for a quick and straightforward computation of DC blocking voltages as a function of FIT rate, n-base doping and temperature. The determination of model parameters is based on the theory and data given in [Zeller HR. Cosmic ray induced failures in high power semiconductor devices. Solid-State Electron. 1995;38(12):2041-6]. With the new approach, calculating first-hand maximum DC blocking voltages for high voltage power semiconductor devices becomes as effortless as the calculation of the breakdown voltage. (C) 2008 Elsevier Ltd. All rights reserved.