What chamber do divers go into to prevent a diving sickness called "the bends"?

Divers go into a hyperbaric chamber to treat decompression sickness, commonly called “the bends.” The chamber raises pressure around the diver, shrinking nitrogen bubbles that formed in body tissues during a rapid or improper ascent.

Under pressure, those bubbles can dissolve back into the bloodstream more readily. The diver usually breathes a high concentration of oxygen while medical staff gradually reduce the pressure according to a treatment schedule. This process is called therapeutic recompression or hyperbaric oxygen therapy.

The bends are caused mainly by dissolved inert gases—especially nitrogen—coming out of solution as pressure falls. Symptoms may include joint pain, tingling, weakness, dizziness, breathing problems, or confusion. The condition can occur even when a diver follows normal procedures, although careful ascent rates, decompression stops, and dive computers reduce the risk.

A hyperbaric chamber is for treatment, not the ordinary way to prevent the problem before every dive. Divers prevent decompression sickness by managing depth and ascent, while suspected cases receive oxygen and urgent medical evaluation before recompression.