lol I worked as an ASSISTANT to an INDUSTRIAL DIVER, and that job has got to be the worst.
You have to be top fit to be a diver in the first place. But Industrial Divers, where do they dive? Yeah, on dams and reservoirs, and on bridge pilings and canal works. That alone is extremely dangerous, as due to the laws of physics and increased gas pressure of gases in the blood caused by diving to depths where great pressure is found, one has to have an exact knowledge of how long one can stay down at a time for each depth that one dives, and an absolutely precise knowledge of the correct procedure to surface with....one does not just head straight for the surface without stopping, or these laws of physics will bring you an extremely painful and maybe fatal case of "the bends." Or one can lose his orientation while diving, as underwater visibility often is quite poor, and one has no reference points for even concepts like "up" or "down" or "left" or "right".
But it only gets worse. Other places where industrial divers dive are in chemical factories, sewerage works, and bio-gas facilities, and even nuclear power plants. One can only imagine what it is like to dive amidst sewerage or bio-gas facilities; even topside, the stench is atrocious and a neoprene diving suit is required to do these things. After each dive, an extremely caustic disinfections substance must be applied to the gear which went down in these places. It is easy to die from infections without doing so. The chemical plants were the same, sometimes involving diving into vats where Ebola and other viruses were burned, at very high temperatures, to maintain these facilities. The facilities themselves are dangerous; one hears of bio-gas facilities that blew up because someone stupid lit a cigarette in the presence of explosive methane fumes, or even just stupidly peered inside an opening into the biogas tank, breathed in poisonous fumes, and died on the spot. Or the chemicals in the vats themselves were extremely caustic. I don't think I need remind anyone of how dangerous it might be to dive in a place like Fukushima, the nuclear power plant that blew up in Japan. And in any of these places, one has to work "blind", by feel, as there is zero visibility there.
In addition to these problems, one has to lug around tons of gear from one job site to another, and often a new job would come with each new day. Divers also had to worry about their air lines getting tangled in objects like trees underwater, and equipment failure of the air delivery systems operating on the surface. The gear one wears simply to dive itself weighs hundreds of kilograms.
Oh, and you can drown, too...or suffer a circulatory collapse from staying in near freezing water or a chemical vat filled with hot chemicals for too long.
As an assistant, I just did the "menial" stuff, like set up the heavy diving gear, let out the heavy air hose and pulled it back in, or did the disinfection work. My boss, who is one of the very best Industrial Divers in all of Europe, has done all of the things above worldwide, and has every diving certificate known to man. But still, I have seen him being airlifted by helicopter to a diving chamber, and one time I saved his life when an air compressor failed while he was at the bottom of an 18 meter biogas tank. But we operated 99.9% of the time in any kind of weather, from 98°F. to -5°F., often for hours at a time, and sometimes during heavy rain- hail- or snowfall, day or night.
Industrial Diving is nearly always ranked at the bottom, or near the bottom, of any survey of "Worst Jobs." And I can vouch for that completely.