How can decompression sickness be prevented effectively?

Pre-breathing 100% oxygen for a period before exposure to lower pressure environments is a well-established method to prevent decompression sickness, also known as "the bends." This practice works by allowing the body to wash out nitrogen that has been absorbed during the period at higher atmospheric pressure. By breathing pure oxygen, the nitrogen levels in the body are reduced, thereby minimizing the risk of bubbles forming in the blood or tissues when the pressure decreases.

This technique specifically helps to saturate the body with oxygen while flushing out nitrogen more effectively than breathing normal air. The 30 minutes duration is generally considered sufficient for this process to be effective before ascending to lower pressures where decompression sickness could occur.

While the other options may contribute to overall safety and health during flight or diving, they do not address the specific mechanism that leads to decompression sickness as effectively as pre-breathing oxygen. Maintaining a steady ascent rate is important for reducing the risk of symptoms of decompression sickness but does not actively reduce nitrogen saturation prior to the ascent. Limiting the depth of dives helps avoid extreme pressures but doesn't mitigate risks associated with nitrogen absorption. Increasing hydration before flight is beneficial for overall health and may assist with the body's physiological responses, but it does not specifically target the