The treatment of dependent failures in availability analyses

This short article will contribute to the development of an easy and handy formula, which enables instrumentation and control (I&C) practitioners to e stimate conservatively the contribution of dependent failure to the overall unavailability of the integrated hardware-software safety-critical I&C-sys tem. The desired formula fits in the existing methodology to quantify the u navailability of redundant hardwired I&C-systems. The methodology has been approved by licensing experts of nuclear facilities in Germany for two deca des. (C) 2001 Elsevier Science B.V. All rights reserved.