In his first annual report on the industry’s performance, Mark Foy said “renewed efforts” were needed to reverse the trend, at a time when many existing reactor sites are transitioning into the defueling and decommissioning phases.

He said: “Findings from our wider interventions across the sector, allied with recent prosecution cases and the increased number of reportable injuries, are indicative of a decline in CHS [conventional health and safety] performance.

“I emphasise the need for increased industry focus to reverse this trend, at a time when the risks from conventional health and safety hazards are increasing."

The chief nuclear inspector said the number of incidents being reported by licensees is too high, having increased by 28% between 2017/18 and 2018/19.

The number of reported nuclear safety incidents in 2018/19 was consistent with the average reported over the last five years.

The ONR regulates nuclear safety and security at 37 licensed sites in energy generation and remediation, research, medicine and defence industries.