When & Where to Conduct a HAZOP
New Design Phase, Modifications & Existing Operations
HAZOP should be done during the design stage of new projects, before plant modifications, and periodically in existing operations to maintain safety standards.
Scope, Nodes and System Breakdown
The process is divided into smaller sections called nodes. Each node is studied to identify deviations in parameters like pressure, flow, or temperature that could lead to safety or operational problems.
HAZOP Study Process & Workflow
Preparing the Team & Documentation
A HAZOP team includes a facilitator, process engineers, maintenance and operations staff, and HSE professionals. Required documents include process flow diagrams (PFDs), piping and instrumentation diagrams (P&IDs), and operating procedures.
Guide-Words & Deviations Approach
Standard guide words such as No, More, Less, Reverse, and Other Than are used to find deviations from the design intent.
Causes, Consequences, Safeguards & Recommendations
For every deviation, the team records the cause, consequence, existing safeguard, and recommendation for improvement.
Reporting, Follow-Up & Action Tracking
The outcomes are documented in a HAZOP report. Recommendations are tracked until all actions are completed and verified.
Techniques, Tools & Best Practices
Multi-Disciplinary Team Structure
A HAZOP should have members from different disciplines to ensure all aspects of the system are reviewed.
Use of PFDs, P&IDs and Nodes
Process flow and instrumentation diagrams are used to define nodes and visualize how each part of the process connects.
Common Guide Words (e.g., More, Less, None, Reverse)
Guide words are applied to process parameters to identify potential deviations and risks.
Ensuring Completeness and Effectiveness
The study must cover all process sections, maintain accurate documentation, and record discussions clearly for review.
Common Pitfalls & How to Avoid Them
Incomplete Documentation or Wrong Scope
Outdated or missing information can cause gaps in analysis. Always verify current data before the study.
Poor Facilitation or Un-Involved Team
The facilitator should lead effectively, and all team members must participate actively.
Overlooking Operability Issues vs Safety Hazards
Both safety and operability concerns must be reviewed equally to ensure complete risk coverage.
Integrating Recommendations into Operations & Continuous Review
Recommendations should be integrated into the plant’s management systems. Regular reviews keep the study valid and ensure continuous improvement.
