Marine fire rooms in steam-powered ships were always extremely hot, were death chambers should a high-pressure pipe break, and almost impossible to evacuate during flooding. Mercifully, oil fuel replaced coal before WWII, ending back-breaking, nonstop hand firing.
A history of Titanic's voyage mentioned several hundred tons of coal were carried for her transatlantic trip, dozens of shift firemen needed, many hired right off the street.
My ship, 50,000hp USS Mansfield DD728, built at the Bath Iron Works in the 1940s with oil-fired dual steam turbines, had HOT, ROARING engine spaces, still with the threat of being broiled to death by superheated steam.
The latest USN vessels--carriers, submarines--are now nuclear powered, with jet fuel-powered turbines running smaller corvette, frigate and destroyer sizes, no hand labor, with enclosed cooler, safer, quieter control rooms.
While visiting Mansfield's engine spaces underway in rough weather to make sure their clocks were accurate, I pleasantly discovered the nearer I was to the ships's center of gravity/moments, the ride was much smoother.

Notice the lucky swabbie shoveler wearing his wide-cuffed dungarees, blue Donald Duck hat and spit-shined shoes. Ah, the good-old daze. Not.