Originally Posted by
guflyer
Does anyone have a guess for what the "random" selection percentage is for pre-check metal detectors? I am curious about whether they have a higher selection rate at airports with body scanners in the precheck lanes than in airports that only use the hand swab for this. Also, I have seen TSOs press buttons at the top and have wondered about whether they are adjusting the rate when they do this.
1)That would be SSI.
2) As for touching the buttons, the majority of the time it's to grab the PAX count of how many passengers went through the WTMD for metrics, because TSA loves metrics.