Depth and Pressure effects
- With depth increasing the pressure also increases which creates a force applied in a circular direction to the surface of the object. The pressure is usually measured in PSI (pounds per square inch). For example 14.7 psi = 1 atm = 33 ft = 1.01 bar. This means that at 99 ft the force applied to the object is 3 times greater than on the surface.
Water Resistance Info
- There are different ways used to seal the watch. The most basic and effective element used today is a rubber gasket or an O ring. For better performance some watches are equipped with a screw down crown, which ensures a good seal between the crown and the case, since most leakage occurs through the crown.
Gasket Replacement Recommendations and Resistance Testing
- To ensure a proper water tight seal it is recommended that the gaskets be inspected and changed every 2 years to prevent rips, tears, and deterioration of the gasket.
- The watch is pressure tested in a dry chamber. The pressure is increased and the smallest variations in case deformation are detected.