If hooks are used to attach cages or buckets to the socket or thimble of a hoisting rope, the hooks shall be self-closing.
053-5 Wyo. Code R. § 77.1907
Sec. 101, Federal Mine Safety and Health Act of 1977, Pub. L. 91-173 as amended by Pub. L. 95-164, 91 Stat. 1291 ( 30 U.S.C. 811 )
48 FR 53242, 11/25/1983