REGULATOR 2ND STAGE, DIVE/PRE-DIVE LEVER EXPLAINED

Some 2nd stage regulators feature a lever on the side, like the RG-3100S, which may leave you wondering about its purpose and effect. This lever controls the Venturi effect, but what exactly is the Venturi Effect, and how does it impact your diving experience?

The Venturi Effect, as described by Wikipedia, refers to the reduction in fluid pressure when a fluid flows through a constricted section of a pipe. In simpler terms, it means that when air moves through a small hole into a larger space, it creates lower pressure. In the context of 2nd stage regulators, this effect makes breathing easier, requiring less effort. Turning the lever off, on the other hand, reduces the likelihood of the 2nd stage regulator free-flowing, providing more control and preventing excessive air release. Understanding the Venturi Effect and how it affects your regulator can significantly improve your dive's comfort and safety.