293.520. No person is permitted to engage in undergroundmining operations, except coal mining, for himself or for anotherunless he is to be employed by an operator as a trainee or towork under the supervision of an experienced miner for suchlength of time as will qualify said person to safely, for himselfand others, perform underground work, or unless he offerssatisfactory evidence that he has for one year worked in mineswith or as a practical miner.
(L. 1959 S.B. 188 ยง 57)