This European Standard specifies the procedures and conditions to be followed for the validation by analysis and testing of: - the safety functions provided, and - the category achieved of the safety-related parts of the control system in compliance with EN 954-1 (ISO 13849-1), using the design rationale provided by the designer. This European Standard does not give complete validation requirements for programmable electronic systems and therefore can require the use of other standards. NOTE CEN/TC 114/WG 6 proposes to deal in more detail with the validation of programmable electronic systems in the elaboration of the revision to EN 954-1 (ISO 13849-1). An application standard for machinery (draft IEC 62061), based on IEC 61508, is under preparation. Requirements for programmable electronic systems, including embedded software, are given in IEC 61508.