Michigan Compiled Laws, Chapter 290. Weights, Measures and Standards § 290.609

Sec. 9. The director, at least once every 5 years, shall test the standards of weights and measures procured by any city or county for which the appointment of a sealer of weights and measures is provided by this act, and shall approve the same when found to be correct, and he shall inspect such standards at least once every 2 years. He shall from time to time test all weights and measures used in checking the receipt or disbursement of supplies in every institution for the maintenance of which moneys are appropriated by the legislature, and report his findings in writing to the supervisory board and to the executive office of the institution concerned.