Your last sentence is a very good point,as is the rank comment-so brownie points there. Differentiation of function is part of my audience participation tactics.
E.g., a safety officer,which I presume to be the white hat, often accompanies visitors for liability /insurance purposes.

As a youngster-cant remember whether it was before or after electricity (is that a bad sign?), I worked as a laborer construction/factories, mostly in non-union shops, so there were absolutely no safety concerns whatsoever- reminiscent of the black lung days,when children would work in the coal mines from age 8 up to 16 hours/day and then die of black lung by 30. But, as some have remarked, CWRN's mine seems to be well organized and clean,with attention to safety,and the various colored hats seem to reinforce the attention to detail. In other words, its not run like a 3rd world mine.

I'll leave it to others to story board the other hat colors.