Which of the following is NOT a component of the pipeline gas supply?

• A. Check valve
• B. Pressure gauge
• C. Flowmeter
• D. DISS protected inlet

Answer: (C)

The correct choice highlights that a flowmeter is not a component of the pipeline gas supply. In an anesthesia machine, the pipeline supply includes the infrastructure that delivers gases from a central source to the anesthesia machine, which is separate from the measurement of gas flow.

Key components of the pipeline gas supply are designed to ensure the safe and efficient delivery of gases, such as oxygen, nitrous oxide, and medical air. A check valve prevents backflow of gases, ensuring that the flow is unidirectional. A pressure gauge is vital for monitoring the gas supply pressure and ensuring it is within safe operating limits. The DISS (Diameter Index Safety System) protected inlet specifically prevents the connection of incompatible gas supplies, enhancing safety during operation.

In contrast, a flowmeter is part of the anesthesia delivery system itself and is responsible for measuring and controlling the amount of gas that is being delivered to the patient. It does not play a role in the pipeline infrastructure, thus making it the correct answer in this context.