49 C.F.R. § 1544.228
This section applies in the United States to each aircraft operator operating under a full program under § 1544.101(a) or a full all-cargo program under § 1544.101(h).
(a) Before an aircraft operator authorizes and before an individual performs a function described in paragraph (b) of this section—
(b) The security threat assessment required in paragraph (a) of this section applies to the following:
(1) Each individual who has unescorted access to cargo and access to information that such cargo will be transported on a passenger aircraft; or who has unescorted access to cargo that has been screened for transport on a passenger aircraft; or who performs certain functions related to the transportation, dispatch, or security of cargo for transport on a passenger aircraft or all-cargo aircraft, as specified in the aircraft operator's security program; from the time—
(ii) An aircraft operator with a full program accepts the cargo until the cargo—
[74 FR 47704, Sept. 16, 2009]