Medical Gas Systems Maintenance
Contributing Author, Roland Lamer RCI TC10001-060 is VP of Operations for National Med-Gas Services, Inc., an affiliate of Environmental Analysis, Inc.
This article may read familiar to you as it originally appeared in a publication entitled: Advance for Managers of Respiratory Care, September 1997. It was written in response to an article that appeared in the May 1997 issue.
The response article was written by Roland W. Lamer, RCI/Medical Gas Systems designer. It addresses the effectiveness of one facility's emergency plan and their ingenuity in providing contingent measures to ensure functional ability of life support systems under adverse conditions. We have reformatted this article as we felt our readers would find the crux of this specific topic educational and informative.
- The Editor
It May Be an Emergency
The article describes an automatic switch-over oxygen manifold that has been installed on the downstream (patient side) of the main line valve for the oxygen system. There are 10 H cylinders on each side of the unit. Only those in the primary (vs. reserve) mode of the automatic system supply the oxygen. When the first 10 cylinders are depleted, the system will automatically switch to the reserve cylinders. The system will also send audible and visual alarms tothe 24-hour monitored master alarm panel.
The article further describes a former emergency procedure where available RT and engineering staff rushed E and H-sized cylinders to critical care areas from a remote storage location. The engineering department would then determine how it would use the H cylinders and zone valves to isolate parts of the system and back-pressure designated piping system zones. The problem with this procedure, as recognized by the facility's management, was the time that would elapse from the instant they recognized a problem existed until they could secure the facility effectively.
With the installation of this 20-cylinder automatic manifold, the facility is confident that they have designed a system that completely eliminates the need for the former procedure and ensures their ability to effectively deal with unanticipated loss of their medical oxygen piped distribution system. However, the automatic changeover manifold as installed is beneficial only under ideal conditions. These include:
- The system loss is located at the liquid oxygen storage unit.
- The system loss is somewhere between the storage unit and the main line valve.
This design leaves most of the system's main line unprotected. If the system failure originates anywhere besides the upstream side of the facility's main line valve, the newly installed unit will yield no benefit.
The portion of the main line protected by this automatic unit would typically represent a fraction of the entire main line that snakes its way throughout the whole building. The loss of main line distribution would more likely originate within the hundreds, probably thousands, of linear feet of pipe networked throughout the building than the relatively few feet ofburied pipe connecting the storing unit to the main line valve. The emergency system must accommodate this entire piping distribution system.
Strategic H cylinder placement throughout the various facility zones provides complete and immediate portability with no conflict of applicable fire and safety codes.
Building and plumbing codes for medical gas systems have required the use of zone, riser, lateral and maintenance valves since 1934. They provide a tremendous level of flexibility in planning varied procedures for the continued use of an impaired piping system. In fact, all that was lacking in that facility's former procedure was a more formal plan that would include:
- a description of the facility's control valves, including their exact location and all medical gas station outlets that they serve
- a documented procedure of back-pressurization techniques supported by periodic in-service training of all engineering, respiratory therapy and nursing staff
- strategic placement of portable storage containers with accessory equipment so that each unit H cylinder is immediately useable without the need to locate and attach regulators, hoses, adapters, etc.
- a step-by-step flow chart designed to simplify implementation procedures during chaotic or stressful conditions.
As a medical gas systems designer, it's exuberating to read an article demonstrating the progressive thinking that obviously exists. The facility recognized their abilities to provide contingent measures to ensure the functional ability of these life support systems under adverse conditions. I believe that a little further study and additional perspective would vastly improve the effectiveness of their emergency plan.