(a) Original inspection service—(1) Lot inspection service. Each original lot inspection service shall be made on the basis of one or more representative samples obtained by official personnel from the commodity in the lot and forwarded to the appropriate location.

(2) Submitted sample service. Each original submitted sample inspection service shall be performed on the basis of the sample as submitted.

(b) Retest inspection service. Each retest inspection service performed on a commodity lot or a submitted sample shall be based on an analysis of the file sample.

(c) Appeal inspection service—(1) Lot inspection service. Each appeal inspection service on a commodity lot shall be made on the basis of a file sample or, upon request, a new sample.

(2) Submitted sample service. Each appeal inspection service on the commodity in a submitted sample shall be based on an analysis of the file sample.

(d) Board appeal inspection service. Each Board appeal inspection service performed on a commodity lot or submitted sample shall be based on an analysis of the file sample.

(e) Use of file samples—(1) Requirements for use. A file sample that is retained by official personnel in accordance with the procedures prescribed in the instructions shall be considered representative for retest inspection, appeal inspection, and Board appeal inspection service if: (i) The file samples have remained at all times in the custody and control of the official personnel that performed the inspection service and (ii) the official personnel who performed the inspection service in question and those who are to perform the retest inspection, the appeal inspection, or the Board appeal inspection service determines that the samples were representative of the commodity at the time the inspection service was performed and that the quality or condition of the commodity in the samples has not since changed.

(2) Certificate statement. The certificate for a retest inspection, appeal inspection, or Board appeal inspection service which is based on a file sample shall show the statement “Results based on file sample.”