During surDO2, where is the first 15 minutes spent?

During surDO2, the first 15 minutes is typically spent at a depth of 50 feet of seawater (fsw). This depth is chosen for the initial phase of decompression and to allow for an optimal environment where the physiological response to the increased pressure can help correct the gas dynamics in the body.

At 50 fsw, the absolute pressure is sufficient to facilitate the absorption of oxygen, which is beneficial for counteracting hypoxia and enhancing the body’s ability to remove nitrogen. This period at this specific depth sets the stage for effective and safe decompression protocols that follow. The conditions at this depth combine both the effects of increased pressure and the controlled environment necessary for safe underwater rescue practices and treatments.

Spending the initial time at different depths, such as at the surface or shallower depths, would not provide the same physiological advantages and could hinder the effectiveness of the rescue practices involved in the protocol.