What is the maximum percentage of oxygen in a chamber atmosphere?

The maximum percentage of oxygen in a chamber atmosphere is 21%. This concentration aligns with the composition of Earth's atmosphere, which is approximately 21% oxygen. Maintaining this level is crucial for safety, particularly in hyperbaric environments, as higher percentages of oxygen can lead to toxicity and other health risks, such as oxygen poisoning.

Hyperbaric chambers are designed to mimic this natural environment to ensure that divers and patients receiving treatment are not exposed to unusually high levels of oxygen that could adversely affect their health or the integrity of the chamber. Keeping the oxygen level at or around 21% strikes the right balance for physiological safety, minimizing the risk of harmful effects due to elevated oxygen concentrations.