What factors influence tolerance to elevated levels of oxygen?

Tolerance to elevated levels of oxygen, particularly while diving with enriched air (Nitrox), is influenced by multiple factors including both time and gas mixtures.

Time plays a crucial role because it determines how long a diver is exposed to elevated partial pressures of oxygen. Prolonged exposure can lead to toxicity, whereas shorter exposures may be tolerable. Understanding the limits of safe exposure times at different depths is vital for divers using enriched air.

Gas mixtures are also significant, as the composition of gases affects oxygen partial pressure. Different Nitrox blends have varying amounts of oxygen, which changes how the body responds to increased oxygen levels. The specific ratio of oxygen to nitrogen in the gas mixture will dictate the diver's risk for oxygen toxicity at given depths and time.

Both of these factors work in tandem to determine a diver's tolerance level. While depth does have an influence since it affects the partial pressure of oxygen, and the wrong choice here suggests it is the only factor, it is more accurate to recognize that both time and the gas mixture are also critical components in assessing overall tolerance to elevated oxygen levels.