New airport security rules took effect Monday at two major British airports that require selected passengers to undergo full body scans. If they refuse, they will not be allowed to board a flight. In a message to Parliament, Britain’s transport secretary predicted that only a few people would be affected, but made it clear that for those who decline to be scanned “they will not be permitted to fly.” The new policy also applies to those under 18. The scanners were installed at Heathrow Airport in London, and at Manchester. Others will be installed at Birmingham, in the English Midlands, later this month. In the U.S. a total of 40 whole-body scanners are installed in about 19 airports. Six of them are used as primary screening devices; the others are used only as backup after full-body pat downs. A total of at least 450 scanners are planned to be installed this year at airports throughout the U.S., according to recent testimony by the Secretary of the Homeland Security Department.

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