What is the partial pressure of 100% O2 at 60 feet of seawater (fsw)?

To determine the partial pressure of 100% oxygen at a depth of 60 feet of seawater, it’s important to understand how pressure increases with depth in seawater.

At sea level, the atmospheric pressure is approximately 1 ATA (atmospheric pressure at sea level). For every 33 feet of seawater, the pressure increases by an additional ATA due to the weight of the water above. Therefore, at 60 feet of seawater, the pressure from the water alone would contribute approximately 2 ATA (since 60 feet is just below 66 feet, which would contribute roughly 3 ATA when accounting for both the water pressure and atmospheric pressure).

To calculate the total pressure at 60 feet of seawater:

• Surface pressure: 1 ATA

• Water pressure at 60 feet: 2 ATA

This gives a total pressure of 3 ATA at 60 feet underwater.

Now for 100% oxygen at this depth, the partial pressure of the gas can be calculated from the total pressure. Since we are dealing with 100% O2, the partial pressure of oxygen is equal to the total pressure because there are no other gases mixed in.

Thus, at 60 feet of seawater, the partial pressure