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Complete Range of Innovative Solutions 25 Safety and Risk Assessment Identification of Safety Function A machine should be constructed to guarantee safety as much as possible. Any potential danger must have its risk reduced/ minimized by protections or measures e.g. a pneumatic safety control system. For unavoidable residual risk, the corresponding necessary documentation must be provided. A comprehensive and standardized risk assessment will take place at the beginning of the process for the evaluation of the machinery safety. If hazardous movements are detected in the risk analysis, counteracting safety functions must be defined and provided. Once a more precise definition of the safety function has been implemented, the corresponding subsystems of the safety control system can be executed and interpreted.. • Safe exhausting of a system • Stop of a hazardous movement • Stop and obstructing of a hazardous movement • Reversing a hazardous movement • Protection against accidental start-up and many others SF = safety function PL = performance level SRP/CS = safety related parts of control systems MTTFd = mean time to dangerous failure DC avg = average diagnostic coverage CCF = control cause failure 1 2 3 4 5 6 7 8 From risk analysis (DIN EN ISO 12100) Identify the safety functions (SF) Setting the properties of each SF Determination of the required PL (PLr) Realizing the SF, identifying the SRP / CS Soware and systematic errors Verification: PL ≥ PL r ? Validation: Requirements met? All SF analyzed? yes no no yes Determining the PL of the SRP / CS from Category, MTTF d , DC avg , CCF to Risk analysis (DIN EN ISO 12100) for every SF Iterative process for the design of the safety-related components of the control system Monitoring Confidence Professional Advice Risk Reduction