Which valves allow modification of lateral branch piping from a main or riser without shutting down the entire main, riser, or facility?

The service valves are specifically designed to enable modifications to lateral branch piping without necessitating the shutdown of the main, riser, or the entire facility. These valves are placed at strategic points in the piping system to allow for maintenance, modifications, or repairs on the branch lines while keeping the main supply active.

This functionality is crucial in medical gas systems, where uninterrupted supply is vital for patient safety and the operation of medical facilities. By using service valves, technicians can isolate specific branches for work, ensuring that uninterrupted service is maintained in other areas and thus supporting continuous care.

In contrast, main and riser valves are typically used for controlling or isolating larger sections of the gas system and would require the interruption of flow for entire sections, while zone valves are employed to control flow within specific areas but may not allow for the same level of precise modification on branch piping alone. Therefore, service valves fulfill the necessary role of enabling isolation for maintenance or modification without major disruptions.