I don't recall any ventilation procedures other than blowers at place at the 10-hundred level at the Idarado in '74. The last thing we did was set off the charges at the end of the shift, then come back 16 hours later to begin the next day (one shift only then on that drift). I guess they figured the stopes would mostly self-ventilate - and they did, as I remember. We carried some sort of emergency breathing kit on our belts, but I never saw one out of its case. Safety training was weak for newbies then - you just watched what other guys did and followed suit.
I remember the MSHA guy (might have been OSHA back then?) coming through and glad-handing the crew every month or two, but nobody took him seriously. Most of the miners were aware that job safety was pretty much on them. If something was obviously amiss (dangerous caving potential, faulty equipment, etc), the company did a pretty good job of taking care of it, IMO. Our shifter, Louie Girado, did all he could to protect us from obvious problems.
The guys knew that if the company had to spend the money necessary to make the mine totally safe, they'd be out of a job, and believe me, they'd rather keep a good-paying job (and it was real good $$$ in '74), than have to find something else in Montrose. I know that's how I felt. But, that was 40 years ago too. I haven't kept up with things in the underground mining game in CO, but I expect that things are generally safer for everyboby - which is good - and I'll wager the pay is way less.
The companies are always targeted when something bad happens, often justifiably, but as I mentioned earlier ... sometimes stuff happens underground that nobody can prevent.
