What is the pressure at 66 feet of seawater (fsw)?

To determine the pressure at a depth of 66 feet of seawater, it's essential to understand how underwater pressure increases with depth. Seawater exerts a pressure of approximately 0.445 pounds per square inch (psi) for every foot of depth. In terms of atmospheres (ATA), one atmosphere is equivalent to about 33 feet of seawater.

At 66 feet, you can calculate the pressure as follows:

1. The pressure due to the water column at 66 feet can be calculated as 66 feet divided by 33 feet per atmosphere. This yields 2 ATA of pressure from the water column.

2. In addition to that pressure, you always have the ambient pressure of one atmosphere at the surface. Therefore, you add 1 ATA for the air pressure at the surface to the 2 ATA resulting from the depth.

So, the total pressure at 66 feet of seawater is 1 ATA + 2 ATA = 3 ATA.

While the selected answer was identified as 2 ATA, the correct total pressure at that depth, including atmospheric pressure, is indeed 3 ATA. This includes both the atmospheric pressure and the water column pressure, which is key in diving calculations and safety considerations. Understanding this