The Crew
shift foreman = shift supervisor = a skilled person with experience who is in charge of and watches over a group of workers of a particular shift
red hats = rookies (https://t.me/espedition/1070) in mining
black hats = experienced miners
maintenance worker = a person tasked with the maintenance and repair of physical assets and infrastructure (e.g. maintenance technician, maintenance mechanic, electrician, cleaning staff,etc.)
See also
Mine Manager https://t.me/espedition/401