brakeman or conductor walking a 100+ car train in cold, looking for pulled draw-bar, busted knuckle, parted air-hose, derailed wheel(s), hotbox/bearing, shifted load, broken rail......
Driving home tonight in windy single digit sleety weather, heard distant train horn and thought of above poor soul who's earning his/her chops working their way up the ladder to that "warm permanent" engineer seat.
And of course, there is the converse of above in high temperature humid heat stroke weather.