Provides the overall framework for the achievement of functional safety. It applies to any safety-related system, which contains at least one electrical, electronic or programmable electronic based component. Also specifies how to refine the information developed in accordance with IEC 61508-1, concerning the overall safety requirements and their allocation to E/E/PE safety-related systems, and covers how the overall safety requirements are refined into E/E/PES safety functions requirements and E/E/PES safety integrity requirements.