AN airport boss has warned that rule-breaking Brits could be adding 20 minutes to everyone's wait time at security checks.
The warning comes amid "total carnage" at Birmingham airport with queues spilling onto the streets.
Clips online showed long lines of frustrated passengers forced to queue for hours like "livestock".
The airport boss has explained that the issue could be lying with flyers who arrive with more than 100ml of liquids in their bags.
Nick Barton, CEO of Birmingham Airport, told BBC: "A non-compliant bag with liquids over 100ml can add up to 20 minutes to each passenger's journey through security."
Spectacular New Year fireworks light up London sky as huge crowds celebrate across UK for first time in three years
Although frequent travellers are familiar with the 100ml rule, all the recent upgrades to security hall scanners might have added to their confusion.
In May, Birmingham Airport has introduced a £60million "state-of-the-art" security hall which allows passengers to carry liquids of up to two litres.
But regulatory approval is yet to be granted for the increased liquid limits at Birmingham.
Mr Barton said: "Since opening our new security area, and despite being one of the first UK airports to comply, we have been limited on the use of our multi-million-pound equipment due to an outstanding regulatory restriction meaning we had to limit liquids to 100ml.
"Despite the 100ml rule still being in place, we continually have non-compliant bags with liquids over the allowance which have led to inefficiencies of our equipment and resulted in extended queuing time for customers."
New CT scanners already allow passengers to keep their liquids and electronics loose in their hand luggage without taking them out of the bag at security checks.
But despite the improved scanners, holidaymakers are still asked to stick to 100ml containers for the meantime.
The advanced tech, which create a 3D image of what is inside passengers' bags, was already in use across five UK airports.
However, Leeds Bradford, London City, Aberdeen, Southend, and Teesside airports have been forced to bring back strict hand luggage rules.
The Department for Transport (DfT) is reimposing the dreaded liquid limit at the five UK airports where it had been erased in what they describe as a "temporary measure".
Robbie Williams poised to launch his own brand of energy drinks to rival Prime
Which UK airports have the new scanners?
Last year, the Department of Transport implemented a deadline of June 1, 2024 for airports to have the new scanners in place.
Several small airports in the UK have already had the new scanners installed, including Teesside Airport in County Durham, London City Airport in London and Aberdeen International Airport in Aberdeen.
London Luton Airport and Bristol Airport also aim to introduce the new technology by the June deadline, with the latter said to be investing more than £10million in the new security equipment.
However, London Gatwick, London Stansted, East Midlands and Manchester Airport have now confirmed scanners will not be functional until 2025.