Until now, all passengers had the option to choose a physical screening instead.

By Michal Addady / Fortune
December 28, 2015
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This story originally appeared on Fortune.

You may not be allowed to opt out of full-body scans at the airport anymore.

The Transportation Security Administration, which manages security for all modes of transport in the U.S., currently uses Advanced Imaging Technologies to discover potentially dangerous items on a traveler's person. Operating protocol generally allows people to opt out of the scan and have a physical screening instead, but TSA just updated its rules.

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Agents can now deny a request to opt out of the scan, "as warranted by security considerations in order to safeguard transportation security." The technology makes it easier to detect "both metallic and non-metallic threat objects."

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The Department of Homeland Security published the updated Privacy Impact Assessment on its website, and echoed the news on Twitter:

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The updated policy comes as both airlines and passengers have grown increasingly concerned about travel security following the November Paris attacks and a plane crash of a Metrojet airliner over Egypt, which Russia has attributed to terror activity.