Title: Scuba Diving Regulators (First and Second Stages)
Headings: How a Scuba Regulator Works
How a Scuba Regulator Works
What a Scuba Diving Regulator Does
The purpose of a scuba diving regulator is to reduce the high pressure air in a scuba tank to a breatheable pressure on demand.
Regulator Terminology
How Regulators Work
The Regulator First Stage:
The Regulator Second Stage:

Content: Common intermediate pressures are around 125 - 150 psi above ambient pressure. Ambient Pressure: The pressure surrounding a diver. Ambient pressure underwater is greater than pressure at the surface because pressure increases with depth. A scuba diving regulator delivers air to a diver's lungs at ambient pressure. Since the ambient pressure changes as a diver changes depth, scuba diving regulators must adjust the air delivered to ambient pressure as a diver ascends and descends. How Regulators Work
Scuba regulators reduce tank pressure in two steps. The first step of pressure reduction is from tank pressure to intermediate pressure, and the second step of pressure reduction is from intermediate pressure to ambient pressure. The Regulator First Stage: The first stage reduces air at tank pressure to intermediate pressure and releases the intermediate pressure air into a hose which feeds into the regulator's second stage.