Miss. Code § 75-27-23
When not otherwise provided by law, the director shall have the power to inspect and test, to ascertain if they are correct, all weights and measures kept, offered, or exposed for sale or purchase. It shall be the duty of the director within a twelve-month period, or less frequently if in accordance with a schedule issued by him, and as much oftener as he may deem necessary to 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 purchased, or offered or exposed for sale or purchase, 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. Provided, that 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 such devices; and the lots of which such samples are representative shall be held to be correct or incorrect upon the basis of the results of the inspections and tests on such samples.
The manufacturer or distributor of any weighing device(s) offered for sale, sold, installed for commercial use or used commercially in this state shall subject such device to type evaluation testing by the National Type Evaluation Program (NTEP), National Institute of Standards and Technology (NIST). Any weighing device not covered by a certificate of conformance from such agency shall not be used commercially in this state.
Miss. Code § 75-27-23