One of the greatest fears new divers face is the thought of an equipment malfunction cutting off air delivery. Rest assured that modern regulators are designed to prevent this from occurring.

The regulator's valves are designed to deliver unrestricted airflow in the event of failure. This condition is called a free-flow because a constant flow of air escapes from the regulator. Failures are rare, but you'll still be able to breathe from the regulator on your way to the surface.

Your regulator may also free-flow when it's out of your mouth and the mouthpiece is pointing up. If this occurs, turn the 2nd stage so the mouthpiece points down, and the free-flow will stop. You'll lose air while the regulator free-flows, so when taking the regulator out of your mouth, make sure the mouthpiece is pointing down.