At what pressure are over-bottoms set on SCUBA first stage regulators?

The pressure at which over-bottoms are set on SCUBA first stage regulators is crucial for ensuring their proper function and safety during dives. The correct pressure of 140 psi +/- 5 signifies an optimal setting that allows for reliable performance of the regulator. This pressure is determined based on the balance between ensuring adequate gas delivery under varying conditions while preventing potential overpressure situations that could lead to equipment failure or unsafe diving scenarios.

Setting the over-bottom pressure too low may result in insufficient pressure during demanding ascent or descent rates, risking the diver's safety. Conversely, setting it too high could lead to excessive strain on the regulator components, increasing the likelihood of failure. The 140 psi specification provides a balance between these two extremes, making it suitable for a wide range of diving circumstances.

Understanding this pressure setting is imperative for divers, as it directly impacts their equipment's reliability and performance underwater, ensuring they can focus on their diving experience rather than worrying about equipment malfunctions.