Travelers passing through Australian airports will soon undergo full-body scans, and refusal to do so would result in missing one's flight.

Under Australian laws introduced this week, any passenger selected for a full-body scan will not be able to request a pat-down, but passengers with serious medical conditions will not be required to go through the scans.

The new airport scans had a successful trial run in Sydney and Melbourne last year. It is Australia's way of upgrading its security system with A$28 million.

The scanners will be rolled out at international airports in Adelaide, Brisbane, Cairns, Gold Coast, Melbourne, Perth and Sydney.

Australian Transport Minister Anthony Albanese assured the public that the scans are safe. It will not show travelers in transparent clothing as in the controversial scanners in the US, and its wave signals would be similar in level to a typical mobile phone call.

"I think the public understands that we live in a world where there are threats to our security, and experience shows they want the peace of mind that comes with knowing government is doing all it can."

Mr. Albanese said the travellers would look like stick figures on the screen, and travelers need not worry about the process because the new scanners are the most sophisticated units of its kind in the world today.

In New Zealand, aviation commentator Peter Clark said Australia's airport security plan seemed to go against recent initiatives to ease travel between Australia and New Zealand.

"Only last week we saw John Key with [Australian Prime Minister] Julia Gillard trying to get passport-free travel across the Tasman, and while this [law change] might mean people do not have to be profiled, it really does seem to contradict this initiative."

Scanners tried in the U.S. have not been well-received due to its time-consuming nature, and the units were described by travelers to be overly intrusive.