At what depth do you experience 3 atmospheres absolute pressure?

To understand the concept of atmospheric pressure and how it relates to depth underwater, it’s essential to note that atmospheric pressure at sea level is approximately 1 atmosphere (atm). As you descend underwater, pressure increases due to the weight of the water above you.

For every 33 feet (10 meters) of seawater, the pressure increases by about 1 atmosphere. Therefore, at a depth of 33 feet, you experience a pressure of 2 atmospheres: 1 atm from the weight of the water and 1 atm from the air above the water.

Continuing this reasoning, at 66 feet, the pressure increases to 3 atmospheres. This is calculated by adding the atmospheric pressure at sea level to the pressure incurred from the water column above. Therefore, at this depth, divers would feel the effect of 3 atmospheres absolute pressure, which encompasses both the pressure from the water and the atmospheric pressure at the surface.

This understanding is crucial for divers, as it highlights changes in pressure underwater and the physiological considerations that arise from it.