Mich. Comp. Laws § 288.714: Dryers, conveyors, sifters, and storage bins; cleaning.

Sec. 154.

Dryers, conveyors, sifters, and storage bins shall be cleaned as often as is necessary to maintain such equipment in a clean and sanitary condition. The kind of cleaning procedure either wet or dry and the frequency of cleaning shall be based upon observation of actual operating results and conditions.