The NFL has advised all teams to start searching fans from the ankles to the knees and the waist up. The old pat-down procedure only checked fans for weapons from the waist up.
The Texans say fans should arrive early to allow for extra time to get through security.
"The enhanced security procedures at the stadium gates are being implemented league-wide as part of the NFL's "best practices" that have been used to ensure the safety of all fans at our games since the 2005 season," said Texans president Jamey Rootes. "This will require some additional time for inspections at the gates. We hope fans will come early, enjoy the league's best tailgating tradition and then head to the stadium gates just a little earlier than they have in the past so that everyone can get to their seats for kick-off."
The enhanced pat-down procedures were recommended to all 32 NFL teams by the league's security office prior to the Week 2 games.