“I think there’s a misunderstanding of what exactly we do sometimes,” he explains. “There’s a lot more to what we do than just standing on a gate with a gun.” A lot of is keeping watch over the delicate transport of nuclear materials.

And nuclear materials are, of course, hazardous. The officers explain that they are constantly checked for radiation exposure.

“That’s on us all the time,” explains one, pointing to his dosimeter. “And if we go into anywhere that has higher levels of stuff then we have monitors on us that actively tell us about what’s going on in the atmosphere around us.”

None here seem anxious about potential exposure to radiation. “I’m not bothered,” the officer adds.

All of the officers here seem to have joined from different backgrounds. One was previously in the prison service. Another says he is ex-military. And a third explains that this is his first law enforcement role.

“I was straight into it,” he begins, before being jokingly interrupted. His colleague quips “from school,” and strokes his colleague’s cheek, patronisingly. They all laugh.

“I think it’s quite good, high camaraderie between us all,” says an officer. “No one outside really understands it. And a lot of people move for the job because obviously you can’t just do it where you live.”

They all agree, training regularly is a favourite part of the role. “We would do it all day, every day if we could.”

It’s physically demanding, however, and officers are expected to maintain a high level of fitness. The CNC has “fitness champions” at all sites who are intended to support officers’ health and help them recover from any muscular skeletal injuries endured on the job. This is part of new measures to lower the average number of sickness absences reported by CNC officers – which has recently been above target levels.

Last year, the CNC lost a legal battle over new rules that mean officers will not be able to retire until they are 65, and eventually not until they are 68. This is because the CNC is not a police force in the usual sense – it is not primarily engaged in the investigation of crime or the maintenance of public order, and is under the supervision of the Secretary of State, not the Home Office. As such, it falls under the category of a public service organisation. Despite this, the Civil Nuclear Police Federation had argued that it is unreasonable to expect officers in this physically demanding role to work for so long.

But the vast majority of officers training here today are much younger than that. And they are enthusiastic – curious about the nuclear power stations they protect.

“A lot of us here, we deal with very sensitive stuff,” says one. The constant training is appreciated, his colleague adds.

The CNC officers training here today all stress that they know the magnitude of the responsibility they signed up for. And in today’s world, in which nuclear assets demand extremely high levels of protection, they are required to be mindful of serious threats.

“At the end of the day, you only get one chance,” the same trainee explains. “You only get one chance if something happens.”

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