The proprietor must gauge spirits, wine, and alcoholic flavoring materials when required to do so by the appropriate TTB officer or when the spirits, wine, or flavoring materials are:
(a) Produced and entered for deposit;
(b) Filled into packages from storage tanks;
(c) Transferred or received in bond;
(d) Transferred between operational accounts;
(e) Mixed in the manufacture of a distilled spirits product;
(f) Mingled under § 19.329;
(g) Reduced in proof before bottling;
(h) Voluntarily destroyed;
(i) Removed or withdrawn from bond;
(j) Tax determined;
(k) Returned to bond; or
(l) Denatured.