(a) Conditions for commercial test. If the importer is dissatisfied with the results of a retest made in accordance with § 151.71(c), he may request that a commercial test be made to determine the percentage clean yield of the wool or hair.

(b) Time for filing request. The importer's request shall be filed in writing with the Center director within 14 calendar days after the date of mailing of the notice of the port director's or Center director's findings based on the retest mailed before January 19, 2017, or within 14 calendar days after the date of mailing of the notice of the Center director's findings based on the retest mailed on or after January 19, 2017.

(c) Procedures for commercial test. The Center director shall cause a representative quantity of the wool or hair in dispute to be selected and tested by a commercial method approved by the Commissioner of Customs. The yield, as determined by such commercial test, shall be suitably adjusted to coincide with the definition of clean yield in § 151.61(b). Such test shall be made under the supervision and direction of the Center director at an establishment approved by him, and the expense thereof, including the actual expense of travel and subsistence of Customs officers but not their compensation, shall be paid by the importer.