Which component connects the gas hose to the wall outlet and the anesthesia machine?

• A. Diameter Index Safety System
• B. Pin Index Safety System
• C. Anesthesia System Display
• D. Auxiliary O2 Flow Control

Answer: (A)

The essential idea is safety through standardized gas connections. The Diameter Index Safety System (DISS) provides unique diameters and threading for each medical gas so the hose from the wall outlet can only mate with the correct port on the anesthesia machine for that gas. This prevents mixing up gases like oxygen with nitrous oxide because the connectors simply won’t fit if the gas types don’t match. The DISS fittings are used for the low‑pressure pipeline connections between wall outlets and the machine.

The other items serve different roles: the Pin Index Safety System is used on cylinder connections to prevent attaching the wrong gas cylinder to the machine, the Anesthesia System Display is just the readout panel, and the Auxiliary O2 Flow Control is a control for adjusting oxygen flow, not the connection mechanism.