053-4 Wyo. Code R. § 75.1103-10
Where the average air velocity along the belt haulage entry exceeds 100 feet per minute, or the belt is not fire resistant, or both, the fire suppression system in the belt haulageway shall conform with the following additional sensor and cache requirements:
(a) The maximum distance between sensors along the belt haulageway shall be 40 percent of those distances specified or established in accordance with S 75.1103-4(a)(1) or (2), as applicable, and shall be installed and put in operation within the period of time specified in S 75.1103-4(a)(3).
(b) For each conveyor belt flight exceeding 2,000 feet in length, an additional cache of the materials specified in S 75.1103-9(a)(1), (2), and (3) shall be provided. The additional cache may be stored at the locations specified in S 75.1103-9(a), or at some other strategic location readily accessible to the conveyor belt flight.
053-4 Wyo. Code R. § 75.1103-10