When not otherwise provided by law, the Secretary may inspect and test, to ascertain if they are correct, all weights and measures kept, offered, or exposed for sale. The Secretary shall, within a 12-month period, or more or less frequently as deemed necessary, inspect and test, to ascertain if they are correct, all weights and measures commercially used (1) in determining the weight, measurement, or count of commodities or things sold, or offered or exposed for sale, on the basis of weight, measure, or of count, or (2) in computing the basic charge or payment for services rendered on the basis of weight, measure, or of count. However, with respect to single-service devices-that is, devices designed to be used commercially only once and to be then discarded-and with respect to devices uniformly mass-produced, as by means of a mold or die, and not susceptible of individual adjustment, tests may be made on representative samples of those devices; and the lots of which those samples are representative shall be held to be correct or incorrect upon the basis of the results of the inspections and tests on those samples. (Added 1967, No. 102, § 10, eff. April 14, 1967; amended 1991, No. 80, § 5; 1991, No. 227 (Adj. Sess.), § 7; 2003, No. 42, § 2, eff. May 27, 2003.)