Washington, Jan 14 (Agencies): Sikhs in the US have been warned that they could now face 100 per cent screening of their turbans at American airports as the new imaging technology cannot see through their 'pagris'.

In a mass email alert to the community members, Sikh Coalition, an advocacy group, told them that they should be ready for additional screening at all the airports.

"Sikhs should now expect to be secondarily screened 100 per cent of the time at American airports, even after passing through so-called Advanced Imaging Technology (AIT) machines," it said.

Although the Transport and Security Administration (TSA) publicly asserts on its website that its newest machines can see through "layers of clothing," the TSA has made clear in both word and practice that such machines are not powerful enough to see through Sikh turbans.

"This means that, for Sikhs, the new machines will lead to more-not less- screening of turbans,” Sikh Coalition said, adding that its assessment is based on feedback from the community and interaction with officials of the TSA and Department of Homeland Security.

The Sikh Coalition rejects the TSA's policy as "unfair and unsafe," and is working with key lawmakers to change it, the group said.

"Even still, in the meantime, we believe that Sikh travellers should at least know what to expect at American airports," it said in its the alert.

"Your turban must first go through a pat-down (either self-administered or administered by a TSA screener) to scan for non-metallic threat items. After this procedure is finished, your turban will now also be subjected to a hand-held metal detector wand search to scan for metallic threat items," says the revised travel guideline issued by Sikh Coalition.

"Please keep in mind that you can always pat-down your own turban. Your turban should also not be ordered removed unless a screener detects something dangerous in your turban either at the pat-down or metal-detecting stage.

According to the TSA, if a person's turban or hands trigger an alarm during explosive trace detection sampling, the person will be required to undergo private screening and remove the turban to resolve the concern, Sikh Coalition said in its guidelines.