What is the required relief setting for valves in central supply systems for positive pressure gases above normal working operating pressure?

The required relief setting for valves in central supply systems for positive pressure gases is designed to ensure safety and prevent over-pressurization. A relief valve set at 50% above the normal working operating pressure provides a critical safety margin, allowing the system to handle unexpected pressure fluctuations without risking component failure or rupture.

Operating pressure can vary depending on the specific gas being used and the intended application; however, the standard industry practice establishes a relief setting at this level as it strikes a balance between safety and operational efficiency. This ensures that in situations where there is an unexpected increase in pressure, the relief valve will activate and release excess pressure, maintaining the integrity and safety of the system.

In contrast, settings of 30%, 40%, and 60% do not align with this safety standard for central supply systems. A 30% setting may not provide adequate pressure relief in many scenarios, while 60% could be excessive, risking unnecessary activation of the valve and potential operational disruptions. Thus, a 50% relief setting is not only a regulatory requirement but also a best practice in ensuring the reliability and safety of medical gas systems.