A major addition to the NFPA 99, Health Care Facilities Code, 2018 Edition is the allowance for the use of Corrugated Medical Tubing, or CMT. This is a new flexible corrugated copper alloy piping similar to that used in other types of fuel gas piping applications. It is a very beneficial option for renovation projects in existing facilities, as well as new and larger projects.
CMT allows for the installation of piping in difficult spaces without multiple brazed fittings, which come with time-consuming and dangerous brazing (hot work) and purging with nitrogen. This new option makes medical gas piping projects much quicker and safer, and decreases the chances of contaminating the pipeline during the installation procedure. CMT will cut labor costs significantly, compared to traditionally installed (purged and brazed) copper tubing installations, especially considering the increasingly stringent burn permit and fire watch requirements in many cities.
CMT comes in rolls, which can be much easier to transport than traditional copper tubing. It has a polyethylene jacket and has similar fire and pressure ratings as copper tubing. The connections are non-separable axial swaged, quick assembly brass fittings requiring no expensive tools. While it is fairly simple, it does require installer training by the manufacturer before installing.