How much oxygen should be breathed at 60 feet after missing time during treatment?

The rationale for breathing the sum of all O2 time missed at 60 feet is grounded in the principles of decompression physiology and the effective management of inert gas elimination. When a diver ascends from depths such as 60 feet, missing predetermined oxygen time during treatment can lead to a backlog of inert gases in the body, particularly nitrogen. This backlog can increase the risk of decompression sickness if not properly addressed.

By breathing the sum of all missed oxygen time, the diver allows for optimal undisturbed decompression, ensuring that the body effectively off-gasses any accumulated nitrogen. This process is crucial for maintaining safety and preventing potential complications associated with insufficient oxygen therapy during ascent.

This approach is based on the understanding that the physiological benefits of supplemental oxygen, both in terms of preventing bubbles from forming and aiding in their elimination, are amplified when the total required therapeutic time is respected. Thus, accurately calculating the cumulative oxygen requirement is critical to ensuring the diver's safety post-treatment.