Mich. Comp. Laws § 29.5m

Sec. 5m. In addition to the requirements specified in section 5j, each remote control terminal at which a tank filled by pipeline is located shall be equipped with a high level alarm system which is fail-safe and will provide an audible trouble signal at the remote control point. The audible trouble alarm shall sound upon the occurrence of any of the following: (a) A loss of the main electrical operating power. (b) An electrical break or ground fault in the alarm initiating circuit or the signaling device circuit. (c) The derangement of the high level alarm system control equipment. (d) The removal of initiating devices. (e) The electrical derangement of the signaling devices.