27 C.F.R. § 28.320
(b) Losses requiring inspection. When it is disclosed that the loss of beer or beer concentrate is large or unusual, the appropriate TTB officer will conduct an investigation of the loss. When it is disclosed that the loss in transit has occurred by reason of casualty, leakage or spillage, credit for the loss will be allowed. When the investigation discloses evidence indicating that the loss resulted from theft or from fraud, the appropriate TTB officer will afford the brewer opportunity to submit a written explanation with respect to the causes of the loss before taking further action.
(Sec. 201, Pub. L. 85-859, 72 Stat. 1333, as amended, 1334, as amended, 1335, as amended (26 U.S.C. 5051, 5053, 5056))
[T.D. ATF-224, 51 FR 7700, Mar. 5, 1986, as amended by T.D. TTB-8, 69 FR 3835, Jan. 27, 2004]