An iris scanning project has gone online today at Heathrow Terminal One, allowing passengers to have their eyes read rather than their passports.
Project Iris is currently available to a volunteer-only group of frequent fliers who have had their irises pre-scanned to allow them to bypass passport checks.
Trials are already running at Heathrow Terminals Two and Four and new users can sign up at the airport.
"Enrolment will take place in the airport departure lounge where immigration officers will assess eligibility and enrol qualifying persons," said the Home Office.
"Those who qualify will have both their eyes photographed in order to capture their iris patterns. This data will be stored securely alongside their personal details, and the enrolment process will take approximately five to 10 minutes."
Passengers using Project Iris will still have to carry a passport, but it is hoped that the system will cut check-in times.
Similar machines will be installed this year in Gatwick's North and South terminals, Heathrow Terminal Three, Stansted, Birmingham and Manchester's Terminals One and Two, at a cost of nearly £3m.
"With over 97 million people entering the country in 2005, it is important that the UK remains at the forefront of the latest technology in immigration controls, and the government's commitment to Project Iris demonstrates this," said Immigration Minister Tony McNulty.
"Secure and effective border controls are vital to safeguard our citizens against terrorism, organised crime and illegal immigration, while facilitating entry for legitimate travellers."
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