Humans can theoretically withstand very high water pressures because the body is mostly liquid and resists compression. Human bones can endure pressures equivalent to depths of about 35 kilometers (22 miles) underwater before crushing, which is far deeper than the deepest ocean trenches. However, lungs and air spaces inside the body collapse at much shallower depths, making safe diving beyond 100 meters extremely dangerous without specialized equipment. The deepest recorded free dive is about 214 meters, while the deepest scuba dive with equipment reached approximately 332 meters. Beyond around 30-40 meters without gear, pressure effects like lung compression and nitrogen toxicity pose severe risks. Essentially, humans are not physically crushed by water pressure at common diving depths, but physiological limits in managing air spaces and gases make diving deeper than a few hundred meters without protection impossible.