a standard, model, or pattern. 2. general level or average: Two cars per family is the norm in most suburban communities. 3. Education. a designated standard of average performance of people of a given age, background, etc. a standard based on the past average performance of a given individual.
For example, pressure regulators are used in gas grills to regulate propane, in home heating furnaces to regulate natural gases, in medical and dental equipment to regulate oxygen and anesthesia gases, in pneumatic automation systems to regulate compressed air, in engines to regulate fuel and in fuel cells to regulate hydrogen.
The regulator does two things: It reduces the pressure from the tank to a safe level for you to inhale, and it supplies air on-demand. First stage - The first stage attaches to the cylinder. It reduces the pressure from the tank (3000 psi or 204 ATM) to an intermediate pressure (140 psi or 9.5 ATM).