TSA Primary Ops is on 172.9000 R $001 however [not having found any yet] there are [at many other airports] simplex channels used for the X-Ray machines [People not Baggage] that all you will hear [if not ENC] is the Person remotely operating the Scanner advising
a. "Male - Clear"
b. "Female - Clear"
c. "Male - Anomaly [insert location(s)]
d. "Female - Anomaly [insert location(s)]
These have bee seen anywhere in the 162 [yes below the NWS] thru 174
on all sorts of other agency shared frequencies [mostly CBP]
Some are P25, others Analog with basic Speech inversion
Note - you need to be close to the terminal/scanner to even pick them up.
Here in Boston, even across the harbor or at Cell-Phone parking we have only discovered 14 of them and some are shared [diff Tone or NAC] with another terminal
Happy Hunting.