Safety analysis and risk assessment (HAZOP, SIL, LOPA, risk graph) using different methods in order to meet customer requirements

Process Hazard and Risk Analysis (PHARA) of manufacturing technology and processes is based on failure and reliability analyzes. PHARA requirements may be based on specific corporate standards and / or national and international regulations and requirements. Current applications of the Best Engineering Practice and Good Manufacturing Practice (GMP) should be considered as well. One of the preferred methods for completion of PHARA is the HAZOP procedure.

The HAZOP (Hazard and Operability) analysis aims to identify and prioritize the consequences of deviations from the planned operations and their risks, and, where appropriate, to formulate suggestions for safety enhancements.

During classification of the process safety elements having SIL (Safety Integrity Level) function, the safety risks of the technical devices are also evaluated. Classification of the SIL categories includes several assessment techniques, e.g. LOPA, risk graph, and so on (see link). The presented SIL classes represent the following categories:

*PFD (Probability of Failure on Demand): the probability that a safety feature does not work upon need.