Some observations on novel concepts in new IEC 61508 draft

IEC 61508 is the basic safety publication with respect to the functional safety of programmable electronic systems. The new IEC 61508 draft CDV (CDV - Committee Draft for Vote), published in October 2008, contains a number of novel or revised concepts. In this paper, these novel and revised concepts will be discussed and scrutinized in particular with respect to aspects of the existence of sufficient technical justification, compatibility with former versions, consequences for sector-specific standards and cross-certification. Where appropriate, alternative justification or concepts will be presented.