What is the maximum allowable depth for surface supplied air diving?

The maximum allowable depth for surface supplied air diving is accurately identified as 220 feet of seawater (fsw). This depth is established based on considerations of the physiological impacts of pressure on divers, as well as the effectiveness and safety of the diving equipment being used.

Pressure increases with depth, and at 220 fsw, divers are experiencing significant atmospheric pressure, which can lead to increased risks such as nitrogen narcosis and other diving-related medical concerns. Surface supplied air is typically used for deeper dives due to the fact that it minimizes the risks associated with breathing compressed air at depth, such as oxygen toxicity and the challenges of managing air supply with portable tanks.

Moreover, industry standards dictate that beyond certain depths, alternative gases or mixed gas diving techniques may be necessary to ensure diver safety. At 220 fsw, divers must also be well-versed in decompression procedures and the appropriate handling of emergency situations, such as equipment failure.

Understanding the reasoning behind this depth limitation is crucial for diving safety and effective planning for deep dives, ensuring that divers are equipped with the knowledge and skills to manage the associated risks.