As 15 million people in the United States head to airports this holiday season — slightly fewer than last year — some travelers will find welcome changes to security screening procedures.

The Transportation Security Administration has expanded its PreCheck trusted traveler program to 35 airports, allowing members who have been deemed low risk to keep shoes, jackets, and belts on. Children 12 and under and passengers 75 and older also receive expedited screening at any checkpoint; pilots, flight attendants, members of the military, and people with top-secret security clearances qualify at some airports.