Final answer:
It is crucial not to exceed an ascent rate of 10 or 20 m/min to avoid decompression sickness, and hyperbaric oxygen therapy is used to treat DCS.
Step-by-step explanation:
During normal diving conditions, you should never exceed an ascent rate of 10 or 20 m/min to prevent decompression sickness (DCS). As a diver ascends to the surface, the pressure decreases, making dissolved gases less soluble and leading to the potential formation of harmful bubbles in the body.
These bubbles can cause symptoms ranging from rashes to paralysis and even death. Therefore, it is critical to ascend slowly or to make decompression stops. If divers experience DCS, they may require hyperbaric oxygen therapy in decompression chambers.