ADC Diving Safety and Procedures Practice Exam

To determine the depth at which the pressure reaches 8.94 atmospheres absolute (ata), it’s important to understand how pressure changes with depth underwater. Atmospheric pressure at sea level is approximately 1 ata. As a diver descends, the pressure increases by approximately 1 ata for every 33 feet of seawater (fsw).

To find the total pressure at a depth, you add the pressure due to the water column to the atmospheric pressure. Here, we want the total pressure to equal 8.94 ata.

Starting with atmospheric pressure at sea level (1 ata), we can set up the equation:

Total Pressure (P) = Atmospheric Pressure + Pressure from Water

P = 1 ata + (Depth in fsw / 33 fsw) * 1 ata

Now, we want to find the depth where P equals 8.94 ata:

8.94 ata = 1 ata + (Depth / 33 fsw)

7.94 ata = Depth / 33 fsw

Depth = 7.94 ata * 33 fsw

Depth = 262.02 fsw (approximately)

This calculated depth (around 262 fsw) isn’t directly provided in the options, but it's