Dual manifold system is the simplest system. Only provide 2 cylinders in service at one time. It is non-extendable system which suitable for small gas applications such as for maintenance and simple gas delivery system etc.
Zone valve boxes are mainly used in medical pipelines to allow maintenance of individual zones without disturbing the gas flow to the zones. In case of emergencies, zone valve boxes can also be used to shut off gas distribution to individual zones.
The assembly is an easily removable over window with pull ring. The window conceal the piping and valves inside the box and labeled “Caution-Medical Gas Shut-Off Valves-Close Only in Emergency” shall be such that the removable window cannot be replaced when any valve is closed.