A diving regulator is a pressure regulator that reduces pressurized breathing gas to ambient pressure and delivers it to the diver. The gas may be air or one of a variety of specially blended breathing gas
If you think about it, breathing underwater is pretty remarkable, and it all happens because of the regulator. The scuba regulator is a great invention that delivers the air from your scuba tank to you just the way you need it to breathe.
A scuba diving regulator is the hub of your dive equipment, and links many pieces of gear – your scuba tank to your BCD, submersible pressure gauge (SPG), alternate air source and you. You’ll always remember your first breath underwater using a regulator – it’s thrilling. However, you’ll soon forget it’s in your mouth as you’re distracted by your dive adventures – which is why you need to have a reliable, easy breathing regulator – so you can forget.
- First stage – Attaches to the scuba tank valve, reduces tank air pressure to an intermediate pressure and routes it to several hoses.
- Second stage – Mouthpiece you breathe from. Also called a demand valve because it gives you air when you demand it (inhale) at the exact pressure you need for breathing comfortably.
- Alternate air source – Spare mouthpiece that provides an easy way to share air in case you need to help another diver. Sometimes the alternate second stage is built into the inflator on your buoyancy control device (BCD).
- Low-pressure BCD inflator – Connected to the first stage by a low-pressure hose. If you wear a dry suit, you’ll have another inflator hose connected to it.
- SPG (submersible pressure gauge) – Connected to a high pressure port on your first stage so that it can sense exactly how much air pressure you have remaining in your tank.