You might be thinking that getting an x-ray every day is bad for the miners, but this is a ye-olde look through machine. Yes it’s bad for the miners, but the guy looking at it is putting his face and uppee body right in the beam here. And I’m guessing he does hundreds of these a day.
Then again, old timey x-ray machines were pretty soft, so (edit) AND the miner is getting big dose of alpha and beta radiation too. And at least the technician isn’t breathing coal dust, so it’s probably a toss up who gets cancers first.