HAZOP

WHAT IS HAZOP?

• HAZOP means hazard and operability analysis and it is a well-known risk analysis method in the chemical and hydrocarbon  industries.
• It consists of a very structured methodology, which provides a guideline to assess process deviation, causes, consequences, and whenever possible to propose recommendations to mitigate risk.
• This technique can be used for continuous or batch processes and can be adopted to evaluate written procedures. The HAZOP team lists potential causes and consequences of the deviation as well as existing safeguards protecting against the deviation.

HOW IS IT DONE?

• For processes plant, the nodes are chosen so that for each a meaningful design intent can be specified and they are commonly indicated on piping and instrumentation diagram (P&IDs) and process flow diagram (PFD).
• For each node in turn the HAZOP team uses a list of standardized guide-words and process parameters to identify potential Deviations from the design intent.
• For each deviation, the team identifies feasible Causes and likely Consequences then decides (with confirmation by subsequent risk analysis where necessary) whether the existing safeguards are sufficient, or whether an Action to install an additional safeguard is necessary to reduce the risks to an acceptable level.
• The examination is repeated until the whole process or section intended to study.

WHY IS IT IMPORTANT?

• The purpose of the HAZOP is to investigate, how the system or plant deviate from the design intent and create risk for personnel and equipment and operability problems.
• Hazard and Operability studies also allow safety professionals to identify and then either control or eliminate hazards.
• HAZOP is ideal for large and complex systems. Breaking these down into their component parts and assessing each in turn gives safety professionals a more fine-grained look at potential hazards that may otherwise be overlooked.
• It can allow you to plan for the worst and prepare for the unexpected, but it’s only the first step. Once your HAZOP study has identified potential risks, those risks need to be addressed and corrected.

INDUSTRIAL APPLICATION

• Modern refinery or gas plant processes operating at extreme temperatures and pressures, where the
• Consequences of a failure are likely to be more serious than on older facility
• Plants involving new processes or significantly altered processes that introduce significant inventory of toxic or flammable materials, where little practical experience is available
• The HAZOP technique has been extended to other areas, including mining operations and other types of process systems and other complex systems such as nuclear power plant operation and software development.
• The HAZOP technique has been practiced in Pharmaceutical Industries in which industries conduct batch reactions using toxic or flammable materials.

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