White Paper · June 2026
The HAZOP Knowledge Problem
Why organizations repeatedly rediscover what they already know.
Every HAZOP creates knowledge.
Most organizations preserve the report.
During a HAZOP workshop, operators contribute operating experience, engineers explain design intent, maintenance personnel describe equipment history, and safety professionals provide risk perspective. Through structured discussion the team develops a shared understanding of process hazards, existing safeguards, and potential improvements.
The final report documents the outcomes. The reasoning, the rejected alternatives, the informal concerns, the assumptions that shaped every judgement — these are rarely captured anywhere. They leave when the people do.
This paper examines why process safety knowledge is so difficult to retain, what the industry's own accident record says about the consequences, and what it would mean to treat that knowledge as a continuous operational asset rather than a periodic deliverable.
What This Paper Covers
- The demographic transition removing experienced personnel faster than organizations can replace them
- Why revalidation so often becomes reconstruction rather than review
- Case analysis of Longford, Piper Alpha, and Texas City — and the knowledge failure each investigation found
- The limitations of static reports as long-term knowledge repositories
- The concept of persistent process safety knowledge and what it would make possible
- A structured discussion guide for leadership teams and study facilitators
Who This Is For
- Process safety managers and HSE leads responsible for HAZOP programs
- Plant managers and operations leaders managing revalidation cycles
- Engineering and reliability teams facing knowledge transfer challenges
- Executives evaluating process safety risk in aging or changing facilities
The paper takes no position on software or vendors. It is an examination of a structural problem the industry has documented for decades but not yet solved.
Download the White Paper
The HAZOP Knowledge Problem
From Periodic Studies to Persistent Knowledge — Trevor Cusworth, June 2026
Vendor-neutral • No product content • Immediate delivery
The Argument
Three cases. Three decades. The same finding.
Major investigations across the process and energy industries have repeatedly identified the erosion or fragmentation of operational knowledge as a contributing factor in catastrophic events. The paper examines three in detail.
Longford Gas Plant
Esso relocated its process engineers off-site. The Royal Commission found that the company's failure to equip workers with appropriate knowledge was the ultimate cause of the explosion. A scheduled HAZOP of the relevant plant had been repeatedly deferred.
Piper Alpha
167 killed. Lord Cullen's inquiry found no written handover procedure and a permit-to-work system applied inconsistently from crew to crew. Safety-critical knowledge about an isolated pump failed to survive a single shift change.
BP Texas City
15 killed. The Baker Panel found that prior warnings and internal study findings had not been acted upon — a failure to apply lessons the organization had already learned. The knowledge existed. It did not reach the decisions it should have informed.
"In each case the knowledge had not been destroyed. It simply was not where it was needed, when it was needed."
— The HAZOP Knowledge Problem, Chapter 4
Inside the Paper
What the paper develops
The Scale of the Problem
Workforce demographics, retirement rates, and the 2.1 million skilled roles projected unfilled by 2030 — with specific data on how the manufacturing sector is affected.
Why Knowledge Disappears
Tacit knowledge lives in people, not systems. The assumptions, rationale, and operating experience that shaped a HAZOP decision rarely appear in the report that records it.
The Revalidation Challenge
Why revalidation so often becomes reconstruction — and what it costs organizationally when teams must relitigate decisions that were, in fact, settled on sound grounds years earlier.
The Hidden Knowledge Pyramid
Reports document conclusions. The reasoning, rejected alternatives, uncertainty, and operational experience that produced them sit below the surface — and disappear when people do.
Persistent Process Safety Knowledge
What it would mean for knowledge to outlive the individuals who created it — remaining connected, understandable, and reusable throughout the operating life of the facility.
Discussion Guide
Structured prompts for leadership teams, study facilitators, and operating crews — organized around where knowledge lives, how well records serve revalidation, and what continuity would require.
Process Safety Intelligence
The challenge is not conducting HAZOP studies.
The challenge is ensuring that the knowledge those studies generate survives long enough to be used. The paper introduces a way of thinking about what that would require.