Is an oxygen concentration of 22% considered safe?

An oxygen concentration of 22% is indeed considered safe in most environments, particularly for human beings. The normal concentration of oxygen in the atmosphere is approximately 21%, so a level of 22% is only slightly elevated and generally does not pose a health risk.

Oxygen levels above 21% can enhance physiological functions, up to a point, without adverse effects under normal circumstances. It is important to note that typical safe levels for humans range from about 19.5% to 23.5%, meaning 22% falls comfortably within that range. High oxygen concentrations, particularly in controlled settings, are managed carefully due to potential fire hazards or effects on the human body at significantly elevated levels, but the slight increase from 21% to 22% does not constitute a danger.

Conditions in which oxygen levels must be regulated, such as in confined or high-risk environments, may necessitate different considerations, but in standard situations, an oxygen concentration of 22% is safe.