A complex chemical manufacturing site was struggling to identify all of its COMAH
(Control of Major Accident Hazards) major accident hazard scenarios. The challenge was
compounded by the fact that corporate ownership was based outside the UK, leading to
a mismatch between UK regulatory expectations and the company’s internal risk matrix
approach. The business needed to demonstrate that all major accident hazards (MAHs)
had been identified and that associated risks were reduced to as low as reasonably
practicable (ALARP) in line with UK COMAH criteria.
We were hired because of our active role in the Chemical and Downstream Oil Industry
Forum (CDOIF) technical working group, where we contribute to the development of
COMAH risk assessment guidance and updates to industry approaches in this area.
My Approach
We partnered closely with the corporate process safety team to advise on the relevant
chemical reaction hazards and the testing required to support robust hazard
identification. Using our regulatory expertise, we applied UK-specific risk tolerability
criteria under COMAH and conducted a detailed hazard identification study aligned with
maloperations for a semi batch reaction on a representative chemical process and
reactor system. This was supported by a review of past industry accidents to ensure
comprehensive scenario coverage.
We then applied semi-quantitative risk assessment techniques, including Layers of
Protection Analysis (LOPA), to evaluate each scenario and to identify where further
measures were required. This assisted in the determination of whether risks were ALARP
and, if not, what additional protective measures were needed.
The Result
The project achieved the following results:
Ensured all relevant major accident hazard scenarios were identified and documented leading to the closure of a legal action.
Provided a template approach which the client could utilise on additional plants and processes.
Identification of aspects of the chemical process which could be altered to provide an inherently safer design, eliminating the need for additional risk reduction measures for some scenarios.
Bridged the gap between corporate and UK regulatory risk frameworks.
Demonstrated compliance with COMAH ALARP requirements using industry- recognised methodologies.
Strengthened the site's regulatory position and internal understanding of UK- specific expectations.
Need support identifying all major accident hazards and
demonstrating ALARP under COMAH?
Book your free 30-minute consultation to explore how to align your hazard
identification process with UK COMAH expectations — and close regulatory gaps using
proven, industry-recognised methodologies.
