Underwater Habitats
As noted above, further extension of the wet bell concept is the moon-pool-equipped underwater habitat, where divers may spend long periods in dry comfort while acclimated to the increased pressure experienced underwater. By not needing to return to the surface they can reduce the necessity for decompression (gradual reduction of pressure), required to avoid problems with nitrogen bubbles releasing from the bloodstream (the bends, also known as caisson disease). Such problems can occur at pressures greater than 1.6 standard atmospheres (160 kPa), corresponding to a depth of 6 metres (20 ft) of water.
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