Medgas installation standard revised and expanded

While the rules regulating medical gas piping systems may vary state to state, there is only one standard covering their installation. The “Professional Qualifications Standard for Medical Gas Systems Personnel (ASSE Series 6000),” written by the American Society of Sanitary Engineers (ASSE), made its debut in 1998. It’s most recent update, in February 2006, contains a few significant changes and lots of helpful new information.

“It’s a pretty good document, and it’s required for anybody that installs medgas to be certified to this standard,” says Greg Maus, a member of the standard’s development committee. Maus teaches a medgas certification course to pipe fitters of Local Union 597 of the United Association. He is one of several UA members from around the country who serve on the committee. Another is Larry Coleman, Maus’s fellow medgas instructor at Local 597. In the late 1990s, when ASSE introduced the standard, both men foresaw the UA’s growing involvement and so jumped in the at the ground level.

In January 1999, they organized a medgas training program for Local 597, one of the first of its kind in the UA. Since then they have trained and prepared more than 900 pipe fitters for certification, fine tuning their course and approach as they went. Next year they’ll add another 150 journeymen and 5th-year apprentices to the number that have completed the combined 39 hours of classroom instruction with hands-on brazing practice in the union’s welding lab.

The process provided in the ASSE standard is ANSI approved, Coleman said. “It’s not so much to license an individual doing the work but to give them a certificate.” He said the National Fire Protection Association (NFPA) has adopted the ASSE standard into its NFPA 99, specifying that everyone who installs medical gas should not only be proficient craftsmen but also meet the qualification of the ASSE standard.

What’s new

The standard has toughened the requirements for the purging of oxygen from pipe before brazing. Purges must be monitored constantly and a low-pressure alarm must be used in the purged line to alert installers if the nitrogen gas supply is about to run out. “The source of the purge gas shall be monitored and installer audibly alerted when the source content is low,” the revised standard reads. If the nitrogen flow drops below 50 psi, the alarm, mounted in a tee next to the regulator, will beep.

“The flow meter lets out a certain amount of nitrogen, and guys have a good idea how much to use,” Coleman said. “But the code went ahead to say they want you to be able to know when the contents of the source gas is getting low. So you have to buy this other device that is going to audibly alert you when the content of the bottle is going low.” Up to now, this idea was simply implied in the standard; now it is spelled out, Maas explained. The purge should displace oxygen down to zero to one percent, and remain on until the brazed joints are cool to the touch.

The new edition of the standard also specifies that all lock ring fittings should come off the top of the pipe. Past standards did not restrict connections to the top, bottom or side, Maus said. Now it wants installers to come off of the top or, if impossible, no more than 45 degrees from the top of the horizontal pipe.

“It’s good piping practice to come off the top on any gases or air, for moisture. But the systems we’re working with are supposed to be moisture-free, down to the dew point of -35 degrees. There shouldn’t be any moisture in the system,” said Coleman.

Maus added that before connecting new lines to existing ones that are several years old, the installer should test the old line before tieing in. “If you are doing a job on an addition, that existing system might be 20 years old and have some particulate in the system.”

Perhaps the most valuable addition to the standard is all the how-to information and procedures for users. This is new. “This document is going to help anybody who doesn’t know something or is searching for more information,” Maus said. There is a procedure in here on how to install medgas, how to inspect it, how to maintain systems if you are the hospital personnel. “It gives you a procedure for everything, including the equipment you need. It’s all in the publication’s annex,” he added.

No longer is the standard written only for installers and inspectors of medgas systems. This edition reaches out to additional parties involved with medical gas systems. Engineers who must design medgas systems, for example, have no way of getting the training they need except by reading the book. Ditto for the salesperson, the estimator. “This gives them the information they need,” Maas said.

Coleman added that medical gas bulk installers, who furnish bulk liquid oxygen and other gases for medical, industrial and food processing facilities, were another targeted group. Members of the Compressed Gas Association, the large distributors, have looked for an independent consensus ANSI standard like this one for a long time. Before this there was no standard that covered their facilities, which are governed by a separate NFPA code. “They wanted the extra meat this provided to their industry. This was big,” Coleman said.

“There’s going to be a lot of hospital work going on for a long time,” Coleman said. “So as people get aware of the nature of medgas and problems that can develop over time, they are going to be more stringent on different areas of the code. It’s up to us to keep preaching what we’ve been preaching over the last 6 or 8 years: Know the code. If you don’t know it, use the book. All the information you need is there.”

Local Unions taking advantage of new model medgas trainers

Instructors Larry Coleman and Greg Maus employ a number of training aids in the medgas course they teach to members of UA Pipe Fitters Local 597, but none more than their homemade model medgas unit. The elaborate, portable unit includes flow regulators, outlets, alarms and other components all mounted on two 10-foot aluminum frames. Everything can be switched on for demonstrations. It’s all on wheels and easily movable.

Over the years, the units received enough compliments from instructors in other Locals to convince them there was a ready market for more. “I’ve seen a big need for the models,” Maus explained. “To teach without a model is kind of hard,” he added. Naturally, plenty of other instructors wanted one, and building the same thing from scratch would probably be too expensive and time-consuming for most people.

With help from the UA Training Department, the two located a Toledo, Ohio-based model builder that can provide a packaged model trainer at a reasonable cost. The smaller, 8-foot model is based on the Chicago-built prototype. It contains the same equipment. There are zone valve boxes, two types of alarms, different types of outlets, a nitrogen flow regulator, and master alarm. One side of the trainer shows what faces the hospital side of an installation, the other the mechanical side (behind the wall).

The builder, Twins 56, already has orders from five local unions, Maus said. One of the models will be displayed at the next UA Instructor Training Program in Ann Arbor, Mich. Twins 56 is located in Toledo and is a signatory employer with UA Local 50 there. For more information, visit Twins 56 at www.twins56.com.