Whitehall is investigating the nuclear regulator after The Times revealed that several serious accidents had been dismissed as posing no safety risk.
The Office for Nuclear Regulation (ONR) has come under fire from experts who argue it is too close to the industry to police it rigorously.

Yesterday an investigation disclosed that the inadvertent discharge of a torpedo at a nuclear submarine docks in Plymouth, a complete power cut at the country’s nuclear weapons base and the contamination of at least 15 workers with radioactive material were among the events it had said were of no concern.

Officials at the Department for Work and Pensions, which is responsible for the ONR, are understood to be looking into whether the regulator is doing enough to keep the country’s reactors, nuclear processing sites and military bases safe.

Although the number of publicly acknowledged accidents has been stable for more than a decade, the rate of incidents judged to be “of no nuclear safety significance” has crept up to more than one a day over the last five years.

Between 2012 and 2015 these included three road accidents involving nuclear material, a dozen leaks and at least 30 fires as well as 70 anomalies on the Atomic Weapons Establishment site at Aldermaston near Reading.

The ONR has said that all of its safety classifications followed international guidelines and insisted that it remained a robust and independent regulator.

Nuclear experts, however, called on the government to launch a review. Stephen Thomas, emeritus professor of energy policy at the University of Greenwich, said the news had reinforced his suspicions that “the first priority for the ONR is not to frighten the horses”.

He said the body had previously ignored warnings about the safety of extending the lifespan of the AGR, an old reactor design that is still in use at seven sites in the UK, as well as the reliability of the newer EPR model, the latest version of which is due to be installed at Hinkley Point C.

“Ironically, since they became an independent body rather than being part of the Health and Safety Executive [in 2014], they seem to have got worse,” Professor Thomas said. “Independence is just a cheap and easy way for government to wash its hands of its rightful responsibility.

“Independent regulators must be accountable to the public and if it is not through a democratically elected government, who is it through?”

Earlier this year the ONR appointed as its chief executive a career civil servant with no background in nuclear engineering. David Toke, reader in energy politics at the University of Aberdeen and a member of the Nuclear Consulting Group, said this suggested that nuclear safety issues were a “low priority” for the organisation.