Project IRIS is being introduced at Heathrow's Terminals 2 and
4 at the end of April 2005 before being rolled out to other UK
airports, and is aimed at anyone not holding an EU passport who
regularly travels through Heathrow. They will be invited to have
their iris patterns photographed and stored in a database upon
departure. Those passengers can then use special automated security
check-points which scan their eyes, avoiding long lines for non-EU
passport holders when they return to the country. The new security
system aims to replace face-to-face passport control interviews and
reducing long queues at the immigration counters.