Executive summary
Date(s) of inspection:
August 2025
Aim of inspection
The aim of this inspection was to assess compliance of the dutyholders arrangements with respect to control of risks associated with potentially explosive atmospheres. This included the following:
- Risk assessment of hazardous areas where explosive atmospheres may be present and the identification of the necessary risk controls as required under the Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR). This follows previous interventions and regulatory issues raised on this topic.
- Implementation and ongoing management of the risk controls identified as necessary to control risks in potentially explosive atmosphere. For risk controls, EC&I equipment was targeted as this is an area where risks are least well understood, as inspection on this topic has not been previously undertaken by the ONR EC&I specialism. The inspection, along with others planned, therefore also sought to provide more strategic benchmarking information of industry compliance.
Subject(s) of inspection
- COMAH - Control of Major Accident Hazards Regulations 2015 - Rating: Amber
- Health & Safety at Work Act - Rating: Amber
Key findings, inspector's opinions and reasons for judgement made
I undertook an inspection to assess compliance of the dutyholders arrangements with respect to control of risks associated with potentially explosive atmospheres. The key findings are:
- From the evidence sampled during this inspection, I judge that Sellafield Ltd. has made significant improvement to their DSEAR risk assessment arrangements and that these assessments identify where risk controls are necessary to control explosive atmosphere risks.
- I found that Sellafield Ltd. has EC&I equipment in place to control ignition sources and detect fires in areas that they have identified as being potentially explosive atmospheres within their risk assessments. However, I found that suitable EIMT of the equipment had not been carried out to identify and address any potential deterioration and non-conformances and there were shortfalls in some of the associated arrangements, which together weaken the risk controls.
- I am satisfied that the dutyholder has other risk controls in place to prevent major accidents and to provide defence in depth for nuclear safety. However, I judge that improvements are necessary to reduce these risks so far as is reasonably practicable.
- I found that Fellside has EC&I equipment in place to control ignition sources and detect flammable gas in areas that they have identified as being potentially explosive atmospheres within their risk assessments. I also found that Fellside had arrangements in place for EIMT and management of these risk controls by suitably competent personnel.
Conclusion
Whilst there was evidence that significant improvement had been made by Sellafield Ltd. with respect to DSEAR risk assessment and identifying where risk controls would be necessary to control explosive atmosphere risks, there were shortfalls in the implementation of the risk controls and ensuring their ongoing adequacy by EIMT. Based upon the evidence sampled, I judge that an AMBER rating (seek improvement) is appropriate for the inspection. I will consider these shortfalls in the context of the wider Sellafield Limited activities and against ONR's Enforcement Guidance.