Definition:
Regulator
This is what you use to breathe the air from the cylinder. The regulator is divided into two parts:
- First Stage
This is the component that attaches to the cylinder and converts the pressurised air inside to what's called intermediate pressure (less pressure than in the tank but still higher than breathing pressure). The regulator usually supplies air to the Alternate Air Source and BCD in addition to the Second Stage Regulator. It will also have an SPG attached to it.
- Second Stage
This is the component that you put in your mouth to breathe. It reduces the air coming from the first stage regulator to ambient pressure (the right pressure for you to breathe).
Also Known As: Reg, First-Stage, Second-Stage, Octopus