The Department for Transport (DfT) has ordered both Heathrow and Manchester airports to introduce body scanners from today.

The new rules will make it mandatory for passengers selected for a scan to participate. Under-18s can now also be tested for the first time.

The security check is already in operation at Manchester’s Terminal Two where body-scanning technology has been on trial since last October, while additional scanners for Terminals One and Three will be installed by the end of the month.

Heathrow said it was unable to comment on when scanners would be introduced although it is thought Terminal 4 will be the first to see the new rules introduced.

Scanners will be introduced at Birmingham airport by the end of February before a “nationwide roll-out of scanners in the coming months”, as ordered by the DfT.

Manchester airport’s head of customer experience, Sarah Barrett, reassured consumers that the x-ray devices would not constitute a breach of privacy.

“We’ve been at the forefront in the development of imaging technology for UK airports and feel we are well placed to introduce this relatively simple, safe and straightforward security process,” she said.

“It will enhance security for everyone, which can only be a good thing, without compromising people’s privacy.

“The image generated by the body scanner cannot be stored or captured nor can security officers viewing the images recognise people.

“Contrary to reports, the equipment does not allow security staff to see passengers naked.”

The government has ordered the additional security as a result of the failed bomb attack on an aircraft landing in Detroit on Christmas Day.