Issue: 1/02

In the shadow of the Gateway Arch in St. Louis, MO, the American Society of Plumbing Engineers held its 2001 Technical Symposium from November 1-4, 2001. The Symposium featured 2 1/2 days of instruction from nationally recognized experts and practicing design engineers on a wide variety of useful topics, including backflow prevention, reverse osmosis, seismic restraint, pumping applications, fuel gas system design, hot water system sizing, sewerage and sump pumps, air admittance valves, medical gas piping, fire pumps, electronic plumbing and greywater treatment. In addition, the Symposium presented a Technical Product Exposition that gave manufacturers of water heaters, pumps, plastic piping, boilers, valves and commercial fixtures the opportunity to display their wares for the 350 plumbing engineers and ASPE members in attendance.

Here is a look at what was presented at some of the Symposium's technical sessions:

  • Metropolitan Industries' Mark Brickey and Brendan Bates discussed sewerage, sump pumps and booster pumps, focusing on choosing the right pump for various applications, including storm water systems and large and small commercial buildings.

    Self-priming units were named as the most widely used pumps for storm water pumping applications inside building basements. Submersible pumps were also mentioned for storm water systems, as they can be used for both indoor and outdoor applications. Self-priming and submersible pumps were also suggested for use with small office buildings, along with recessed impeller submersible pumps for use with heavier solid concentrates and grinder pumps for longer piping runs.

    Types of impellers were detailed as well, and the components of several pumps were discussed, as were the installation diagrams for different applications. Calculations for determining volume and pump size were also presented.

  • Mark Allen of Beacon Medical Systems spoke about the considerations involved with connecting old and new medical gas and vacuum lines. Preparation, he said, is one of the most important factors. Dirt, foreign material in the piping, flow problems and water in the lines can all cause operating problems, whether the disturbance is in the old work or the new, he said, so inspections and testing of both systems must be done before the tie-in is performed.

    Making sure the new work is clean, leak free and flows correctly is the first step in preparing for the tie-in, Allen advised. The new work must be constructed in isolation according to NFPA, he said, and the new work must also be tested in isolation before the tie-in is performed. Annual testing of the old work should've been done by the facility, but the engineer should make sure to see the surveys pre-test.

    Other issues to consider, Allen said, are the methods of joining the piping, the design angle, inline filtration, gas compatibility and compliance with new and existing standards for medical gas piping. Allen also stressed the importance of purging, testing and verifying the test results after the connection, on both the new and old piping, before the system is put into use.

  • Ford Motor Co.'s Ron Chapman presented a program on backflow preventer applications, design and specifications. He said that when deciding what type of backflow preventer to use for an application, various factors need to be considered. First, you must determine the type of backflow hazard you are facing, either low (pollution) or high (contamination), as well as the way in which backflow will occur, either by backpressure or backsiphonage. Backpressure is a pressure rise of the downstream piping system above the supply pressure that would cause or have a potential of causing a reverse direction of flow. Backsiphonage is a phenomenon that occurs when a reversal of flow is caused by negative pressure.

    There are five basic means of backflow protection that can be used with varying degrees of success in these applications, according to Chapman. They are air gap, dual check valve type, vacuum breakers, double check valve assemblies, and reduced pressure assemblies.

    Air gap is the physical unobstructed vertical distance through free atmosphere between the lowest opening from any potable outlet and the flood level rim of a receptacle. According to Chapman, air gap offers the highest level of protection, as it protects against both backsiphonage and backpressure, as well as high and low hazard.

    Vacuum breakers are designed to break the vacuum caused by a negative pressure in the line, and they protect against both high and low hazard, but they are only effective in protecting against backsiphonage, Chapman cautioned.

    A dual check valve is effective against both backpressure and backsiphonage, but only protects against low hazard and is subject to continuous pressure.

    A double check valve assembly protects against backpressure and backsiphonage, and installs as an assembly, but it only protects against low hazard.

    Reduced pressure assemblies protect against low hazard and high hazard, as well as backpressure and backsiphonage. This is the highest form of mechanical protection, according to Chapman, but it is subject to causing water damage.

    After determining what conditions of backflow exist, and what type of backflow protection to use, other requirements will also have to be considered, Chapman added. It must be an approved device, it must be in compliance with local codes, and it may also need to meet some approved listings. He also discussed the special needs for fire protection applications and NFPA requirements, as well as installation recommendations.

  • ASPE also held its Leadership Caucus during the Symposium, allowing its members an inside look at the new programs and services the association is developing, as well as the chance to provide input to the Board of Directors.

    Reports were presented on the various branches of the board. The Research Foundation reported on a project to develop a new test bulk media for the ASSE/ANSI water closet test. A plumbing research project on ultra-low flow water closets was also discussed.

    The Convention Committee presented a report on the 2002 Dallas/Ft. Worth ASPE Convention.

    The Technical Committee reported on the availability of ASPE's updated Databook 3, as well as the work being done on Databook 4.

    The Education Committee recognized several chapters for their local educational seminars, and also discussed the "Long Distance Learning" program for members living in rural areas without access to local chapter meetings and seminars.

    The Legislative Committee reported on the availability of ASPE's CD-ROM listing state contact names and addresses.

    The Membership Committee announced that as of Nov. 1, 2001, ASPE had 7,501 members, 61 chapters and one satellite chapter in High Plains, TX.

    A discussion among members and the board followed. Topics included ASPE's CIPE Recertification Program, the reformatting of ASPE's Web site and recognition of Certified Plumbing Designer (CPD) status. Awards recognizing merit, membership growth and retention, as well as certificates of appreciation and for the research foundation, were presented.