Which has a higher floodable volume, an aluminum 80 or a steel 72?

The correct answer highlights that a steel 72 has a higher floodable volume compared to an aluminum 80. The key reason behind this lies in the construction and design of the two types of cylinders.

Steel cylinders, such as the steel 72, typically have thicker walls than aluminum cylinders, which allows for a denser storage of gas under pressure. Even though the “72” in steel 72 refers to its water capacity in cubic feet, it is important to note that it can hold a significant amount of compressed air, leading to a higher total floodable volume when it is fully filled.

In contrast, an aluminum 80, despite its design being suitable for recreational diving, has a different structural integrity and design capacity that usually translates to a slightly lower floodable capacity in comparison. Therefore, when assessing the floodable volumes of both cylinders, the steel 72 emerges as the better choice for maximizing the amount of air or gas that can be utilized while diving.

This understanding of how cylinder materials and designs affect their capacities is crucial for SCUBA divers, especially when planning dives where air supply and buoyancy considerations are essential.