What percentage change in medical gas line pressure activates the Master Alarm?

The Master Alarm in medical gas systems is a critical safety feature designed to alert medical personnel to changes in gas line pressure that could indicate a malfunction or supply problem. According to standards set forth in NFPA 99, the Master Alarm is programmed to activate at a 20% change in pressure from the norm.

This threshold ensures that any significant drop in pressure—which could potentially jeopardize patient safety—is promptly addressed. By setting the activation point at 20%, the system minimizes the risk of unnoticed supply issues, allowing staff to take immediate action to ensure that medical gases are delivered at the appropriate pressure for safe patient care.

Understanding that this percentage reflects a direct commitment to patient safety helps reinforce the importance of adhering to these standards in healthcare facilities. The other percentage options are lower or higher than the established safety standard, which would not adequately address the risks associated with medical gas supply failures.