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?"