The cab as a work station

Obviously not limited to narrow gage or any particular RR, practices in the days steam ruled the rails.

I was just watching a snip of a video of a fireman hand bombing with lumps of coal that looked to be the size of bowling balls. Then I wondered what the occupational hazards were for engine crew back in the day. I can imagine you got benefits of the physical labor, but I understand that loss of hearing was not uncommon. Was there any other issues that comes along with the job on either side of the cab? I thought about vision issues having to look inside the firebox.

How was the job progression, as a person looking for his first job on the railroad, where was one likely to start if his goal was engineer? Was fireman part of the job progression to engineer?

Thanks for your answers.
Mike