Manifolds for gas cylinders shall consist of ______ equal headers; each with one average day's supply, but not fewer than _______ connections.

• A. three - three
• B. two - two
• C. four - four
• D. one - one

Answer: (B)

Two equal headers provide redundancy and a reliable daily supply. In a gas-cylinder manifold, splitting the system into two identical banks means you always have a full day’s worth of gas ready in each header. If one header is depleted or needs attention, the other can still deliver gas without interrupting patient care. Each header must hold at least one day’s supply, ensuring the system can be switched over smoothly while keeping the flow steady. Having at least two connections per header means multiple cylinders feed into that header, which helps distribute the load, avoids relying on a single cylinder, and allows parallel changes without dropping supply. Using more than two headers would complicate the setup unnecessarily, while a single header would eliminate the necessary redundancy.