I was referring to the security officers who stand next to the machines everyday. They were forbidden from measuring anything related to occupational exposure. At one point the TSA found itself caught in so many lies about their supposed "testing" that they ran a very public PR-style limited study. Coincidentally, nowadays the backscatter scanners have been quietly replaced with millimeter wave scanners.

Anyway the point of my comment wasn't to re-litigate this. It's more that the original comment struck me as "can't the fox just guard the henhouse?"

An officer traditionally has been a person in military with a commission (or NCO), or police. TSA are government employees, with self-created pretend titles and fake badges. TSA can't detain or arrest and if scan tunnel shows possible weapon the TSA aren't allowed to touch it and the line cop does that.