49 CFR § 1540.107 - Submission to screening and inspection.
(a) No individual may enter a sterile area or board an aircraft without submitting to the screening and inspection of his or her person and accessible property in accordance with the procedures being applied to control access to that area or aircraft under this subchapter.
(c) An individual may not enter a sterile area or board an aircraft if the individual does not present a verifying identity document as defined in § 1560.3 of this chapter, when requested for purposes of watch list matching under § 1560.105(c), unless otherwise authorized by TSA on a case-by-case basis.
(d) The screening and inspection described in paragraph (a) of this section may include the use of advanced imaging technology. Advanced imaging technology used for the screening of passengers under this section must be equipped with and employ automatic target recognition software and any other requirement TSA deems necessary to address privacy considerations.
(1) For purposes of this section, advanced imaging technology-
(ii) May include devices using backscatter x-rays or millimeter waves and devices referred to as whole body imaging technology or body scanning machines.
(2) For purposes of this section, automatic target recognition software means software installed on an advanced imaging technology device that produces a generic image of the individual being screened that is the same as the images produced for all other screened individuals.