What is equivalent to one atmosphere in feet of sea water?

One atmosphere is equivalent to 33 feet of seawater (fsw). This measurement is foundational in diving physics and safety practices. At sea level, atmospheric pressure is 14.7 pounds per square inch (psi), which corresponds to the pressure exerted by a column of seawater that is 33 feet high.

As divers descend underwater, the pressure increases due to the weight of the water above them. For every 33 feet of seawater, divers experience an additional atmosphere of pressure. This understanding is crucial for divers as it helps them calculate decompression schedules, gauge their limits, and recognize signs of pressure-related issues like nitrogen narcosis or decompression sickness. Thus, knowing that one atmosphere equals 33 feet of seawater is essential for safe diving practices and preparing for the physical effects of pressure changes underwater.