It is recommended that small mines, regardless of size, affiliate with a cooperative mine rescue station wherever practical. Where it is not practical, each mine should have some man in its organization who is trained and qualified in the use of breathing apparatus, to accompany mine rescue crews into the mine in case of emergency. This man should be familiar with the mine workings, mine ventilation, water lines, electrical circuits, and underground hoists.
Cal. Code Regs. Tit. 8, § 7083