Hazard Analysis
What is What-If Analysis? A Lighter-Weight Hazard Identification Technique
Vinit Pandey · Published 4 August 2026
In short: What-If Analysis is a qualitative hazard identification technique in which a review team poses structured 'what if' questions about a process to uncover hazards and operability concerns, often used as a lighter-weight alternative to HAZOP for lower-complexity or lower-hazard processes.
Key takeaways
- What-If relies on team-posed open questions rather than HAZOP's systematic guide-word structure
- Generally appropriate for lower-complexity or lower-hazard processes, not high-hazard continuous units
- Coverage quality depends heavily on team composition and experience, more so than in HAZOP
- Often combined with checklist review to balance systematic coverage with open-ended exploration
Unlike HAZOP's systematic guide-word-by-parameter approach at every node, What-If Analysis relies on the review team's experience and judgement to pose open-ended questions such as 'what if this pump fails while the tank is being filled', making it faster but more dependent on team expertise to achieve adequate coverage.
What-If Analysis is generally considered appropriate for lower-complexity or lower-hazard processes, or as a supplementary check alongside a checklist-based review, rather than as the primary method for a high-hazard continuous process where systematic node-by-node coverage is warranted.
Because What-If Analysis lacks HAZOP's built-in systematic structure, its quality depends heavily on team composition and experience — a team lacking someone familiar with a specific hazard category is more likely to miss it than in a fully systematic guide-word review.
Many facilities combine What-If Analysis with a checklist review, using the checklist to catch known hazard categories systematically while the open-ended questions surface less common, process-specific concerns the checklist wouldn't anticipate.