In the actual bell/moon pool room, the pressure will be equal, with all the problems that come with it as others have explained.
Some bigger setups have separate compartments that can be at a different pressure, but these have to be separated from the water with a pressure tight door.
If you open these doors without slowly equalizing the pressure first, you get the infamous Byford Dolphin incident. Quotes (NSFL):
>!Medical investigations were carried out on the remains of the four divers and of one of the tenders. The most notable finding was the presence of large amounts of fat in large arteries and veins and in the cardiac chambers, as well as intravascular fat in organs, especially the liver. … The autopsy suggested that rapid bubble formation in the blood denatured the lipoprotein complexes, rendering the lipids insoluble. The blood of the three divers left intact inside the chambers likely boiled instantly, stopping their circulation. The fourth diver was dismembered and mutilated by the blast forcing him out through the partially blocked doorway and would have died instantly.!<
>!… forced through the crescent-shaped opening measuring 60 centimetres (24 in) long created by the jammed interior trunk door. With the escaping air and pressure, it included bisection of his thoracoabdominal cavity, which resulted in fragmentation of his body, followed by expulsion of all of the internal organs of his chest and abdomen, except the trachea and a section of small intestine, and of the thoracic spine. These were projected some distance, one section being found 10 metres (30 ft) vertically above the exterior pressure door.!<
On top of what others have already addressed regarding the pressure in the bell being equal to the water pressure, your foot wouldn’t really be crushed anyways. There aren’t any hollow spaces to be compressed. The main areas of your body that are susceptible to be crushed by pressure like that are the air cavities: your lungs, air ways, sinuses, etc. There are some limits to this, mainly once you get to pressures that are able to compress water a meaningful amount.
This old reddit post covers the compression of water:
How much pressure is needed to compress water?
by inaskscience
No, the air pressure in the diving bell is equal to the pressure of the water, so to you it will feel like it’s just regular water.
However, at their high air pressures they can’t actually fill the bell with air, as that would kill you (nitrogen becomes toxic), so they’d fill it with helium and oxygen…and then you [sound like a chipmunk](https://youtu.be/ACXlVEomWZY?t=94).
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