Functional safety of electrical/electronic/programmable electronic safetyrelated systems - Part 6: Guidelines on the application of IEC 61508-2 and IEC 61508-3
This part of IEC 61508 contains information and guidelines on IEC 61508-2 and IEC 61508-3. ?C Annex A gives a brief overview of the requirements of IEC 61508-2 and IEC 61508-3 and sets out the functional steps in their application. ?C Annex B gives an example technique for calculating the probabilities of hardware failure and should be read in conjunction with 7.4.3 and Annex C of IEC 61508-2 and Annex D. ?C Annex C gives a worked example of calculating diagnostic coverage and should be read in conjunction with Annex C of IEC 61508-2. ?C Annex D gives a methodology for quantifying the effect of hardware-related common cause failures on the probability of failure. ?C Annex E gives worked examples of the application of the software safety integrity tables specified in Annex A of IEC 61508-3 for safety integrity levels 2 and 3. IEC 61508-1@ IEC 61508-2@ IEC 61508-3 and IEC 61508-4 are basic safety publications@ although this status does not apply in the context of low complexity E/E/PE safety-related systems (see 3.4.3 of IEC 61508-4). As basic safety publications@ they are intended for use by technical committees in the preparation of standards in accordance with the principles contained in IEC Guide 104 and ISO/IEC Guide 51. IEC 61508-1@ IEC 61508-2@ IEC 61508-3 and IEC 61508-4 are also intended for use as stand-alone publications. The horizontal safety function of this international standard does not apply to medical equipment in compliance with the IEC 60601 series. One of the responsibilities of a technical committee is@ wherever applicable@ to make use of basic safety publications in the preparation of its publications. In this context@ the requirements@ test methods or test conditions of this basic safety publication will not apply unless specifically referred to or included in the publications prepared by those technical committees.