HAZOP and LOPA are most commonly used tools for identifying risks in the process industry.

Zhunyun consultants will provide services according to the following approach:

(1) Determine the process and boundary of the analysis, the design intention of the process, and collect process safety information, including: chemical list and physical and chemical properties, process control chart, equipment chart, design basis, etc.

(2) Define the deviation, identify the initial event and possible consequences (that is, the accident scene), and finally calculate the occurrence frequency of the subsequent event based on the determined initial event, intermediate event (or enabling event), and conditional modifier.

(3) Determine the consequences and severity level of scenarios, and then assess the likelihood of the consequences. With likelihood and severity level, risks can then be evaluated for this scenario.

(4) List all safety measures and identify the independent protection layers (IPLs) among them, and then determine their probability of failure, and calculate the residual risk and its risk level of mitigated consequence when considering independent protection layers. The likelihood of the mitigated consequence is equal to the product of the likelihood of the non-mitigated event and the probability of failure of each independent protection layer (also called as PFD).

(5) If the residual risk reaches an acceptable level, no further safety measures are required. Otherwise, additional safety measures should be proposed until the residual risk is reduced to an acceptable risk level.