The Interface Problem in Medical Gas Projects

In hospital construction and renovation, the oxygen wall outlet and the flowmeter are often treated as a single line item. They are not. The wall outlet is a fixed terminal unit within the medical gas system; the flowmeter is a separate point-of-use device that connects through a compatible inlet. Ordering one does not automatically include the other, and matching gas labels alone do not prove that their connection systems will fit. For procurement and engineering teams, the critical question is not which device is better, but how to ensure the two interfaces are specified, sourced, and installed as a coordinated pair.

What the Wall Outlet and Flowmeter Each Provide

The wall outlet provides a standardized connection point for medical gas delivery. Its design, including the gas-specific index and the probe or connection format, is determined by the facility’s medical gas system. The flowmeter regulates and indicates gas flow at the point of use. It attaches to the outlet via an inlet that must match the outlet’s connection system. The proposed combination must be checked as an interface: the outlet type does not establish which point-of-use device is appropriate, and a flowmeter cannot connect to an incompatible outlet. Procurement decisions for one therefore affect the other.

Key Questions for Procurement and Engineering

When planning a project, the following questions help clarify the interface requirements:

• For existing rooms: What is the installed outlet family? Obtain the approved outlet drawing, probe specification, or a controlled sample from the facility.

• For new construction: Have the outlet and flowmeter interfaces been placed on a single coordinated schedule before either item is ordered?

• Does the proposed flowmeter inlet match the outlet’s connection system as confirmed by the facility’s technical team and the exact model documents?

• Are seals, adaptors, or accessories included with either item? Which are required for a complete installation?

• If a mismatch is identified, what is the facility’s approved procedure for resolution? Improvised adaptors should not be used without technical approval.

These questions are not exhaustive, but they frame the interface verification that must occur before purchase orders are issued.

Practical RFQ Checklist

Use this checklist when requesting quotations for oxygen wall outlets and flowmeters:

• Provide the approved outlet drawing or probe specification for each room type.

• State the exact flowmeter inlet required, referencing the outlet connection system.

• Confirm whether the flowmeter is supplied with a probe, nut, and seal, or if these are separate.

• List quantities by room and note any variations in outlet types.

• Request that the vendor identify the exact model numbers and provide interface documentation.

• Clarify which party is responsible for verifying compatibility: the facility’s technical team, the contractor, or the vendor.

• Include a requirement that any substitution of outlet or flowmeter models be approved by the facility before delivery.

This checklist is intended to be adapted to the specific project and facility requirements.

Where Responsibility Lies

Clinical staff determine device selection and operating settings under their own procedures. This article addresses the purchasing interface only. The facility’s technical team is responsible for confirming that the proposed outlet and flowmeter interfaces are compatible with the installed medical gas system. Vendors should provide accurate model documentation, but they cannot approve a connection without the facility’s verification. Procurement’s role is to ensure that the RFQ and purchase order reflect the technical decisions made by the facility.

Coordinating the Purchase

Review Kersai's gas outlet range and oxygen flowmeters together. When requesting a quotation, send the project interface specification to request matching model documents. This allows the vendor to identify the correct models and provides the facility’s technical team with the information needed to verify compatibility. By treating the outlet and flowmeter as a coordinated pair from the start, projects can avoid delays and rework caused by interface mismatches.