Safety and SIS · Glossary

What is HAZOP?

hazard and operability studySafety and SIS

HAZOP is a structured team review that uses guide words to find hazards and operability problems in a process design.

HAZOP Explained

The team takes each node of the P&ID and applies guide words such as no, more, less and reverse to parameters like flow, pressure and level. For each deviation it lists causes, consequences and safeguards.

Scenarios needing more protection go to LOPA or other risk analysis. IEC 61882 gives guidance on HAZOP.

Calculators for HAZOP

CalculatorLOPA SIL CalculatorFree online calculator with formula and worked example.CalculatorFault Tree CalculatorFree online calculator with formula and worked example.

Free Downloads

Free downloadMOC Form Template in ExcelFree download in Excel and PDF.

Frequently Asked Questions

What is HAZOP?

HAZOP is a structured team review that uses guide words to find hazards and operability problems in a process design.

Who should attend a HAZOP?

Process, instrument, mechanical and operations people, with an independent chair and a scribe.

When is a HAZOP repeated?

After significant changes through MOC, and in periodic revalidation.

Learn more on the blog

What is SIL (safety integrity level)

A practical guide on instrumentationblog.in with more detail on HAZOP and how it is applied on real plants.

Read Full Article

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