Area Valve Service Units (AVSU)

• Isolating the area in an emergency such as fire or a leak inside the department.
• Isolating the area for maintenance or modification without stopping other departments.
• Providing a measurement and monitoring point for zone pressure.
• Providing a test point during commissioning and periodic inspection.

• An enclosure with a break-glass or quick-open front for emergency access.
• An isolation valve per service in the area (oxygen, medical air, vacuum and others as applicable).
• A pressure indicator for each service.
• Identification labelling stating the area served and each service name.

The unit must sit outside the area it isolates but close to it, in a visible and accessible position not obstructed by furniture or equipment, and at a height allowing rapid operation. Installing it inside the room it serves defeats its purpose in a fire or evacuation.

Closing an AVSU stops gas to every terminal unit in the area, so the decision must be coordinated with clinical staff because patients may depend on oxygen at that moment. Teams are trained in advance: who authorises closure, who informs nursing, and when and after what verification the valve is reopened.

• Verifying label clarity and the accuracy of area and service names.
• Confirming access is not obstructed by furniture or equipment.
• Checking pressure indicators against the alarm panel.
• Verifying the enclosure front and quick-open mechanism are intact.
• Recording the inspection in the preventive maintenance log.