Immediately outside each Category 1 space and anesthetizing location, there shall be located which device for each medical gas, vacuum and WAGD system?

• A. zone valve
• B. fire extinguisher
• C. area alarm
• D. relief valve

Answer: (A)

Zone valves are used to isolate portions of the medical gas, vacuum, and WAGD distribution system. Placing a zone valve immediately outside each Category 1 space and anesthetizing location allows rapid shutoff of gas supplies to that space if needed—such as during a leak or emergency—without shutting down the entire building system. This targeted isolation helps protect patients and staff from exposure and makes safety interventions faster and more precise.

Area alarms detect issues but don’t stop gas flow. Fire extinguishers address fires but don’t isolate piping. Relief valves manage system pressure rather than provide space isolation. So the zone valve is the device specified for this location.