New Toilet Testing Transforms Performance

Alex Wilson - This article was produced by BuildingGreen, Inc.- www.buildinggreen.com

A plethora of new toilets have come onto the market in the past few years: dual-flush, pressure-assist, vacuum-assist, and advanced-flush toilets with larger-diameter flush valves, flapperless flush valves, and highly polished porcelain surfaces that minimize staining. Dozens of toilets have been introduced that use at least 20 percent less water and are considered high-efficiency toilets in some rebate programs and in the new Uniform North American Requirements (UNAR) criteria.

One of the drivers of this innovation has been a newer and far more realistic testing protocol to rate the flush performance of toilets. Called Maximum Performance (MaP) testing, this provides, for the first time, a quantitative assessment of real toilet performance. To understand why it’s such a big change, it’s helpful to look at what the industry had done up to now.

Toilet performance has, for decades, been governed by standards created by the American Society of Mechanical Engineers (ASME), using test standards developed by volunteer committees made up of industry representatives. Essentially, toilets in the U.S. have been designed to flush ASME-standard plastic balls, plastic granules, paper balls, dye, and sponges—and they did a very good job with that.

For better or worse, human waste is distinctly different from plastic balls and sponges. So when it came to performance in the field, even toilets that passed the ASME tests with flying colors sometimes didn’t perform satisfactorily. “Manufacturers did not recognize real-world performance in the design of their products,” says water conservation expert John Koeller, an engineer with Koeller and Company. Municipal water utilities with programs to subsidize the purchase of water-efficient toilets often received complaints about performance from users who had to flush twice or clean the toilets too often.

Enter the MaP testing. Developed by Koeller and William Gauley, and engineer with Veritec Consulting, MaP testing involves reusable 50-gram “sausages” of a soybean paste encased in latex sleeves. This test media is added to the toilet bowl and the toilet is flushed; if successful, the toilet is tested again at the next higher loading increment—using mass loadings of 250g, 300g, 350g, 400g, 500g, 600g, 800g, and 1,000g. A toilet must successfully flush all of the test media in four out of five attempts to end up with that MaP rating. A loading of 250 grams is considered the minimum for “satisfactory” performance, but there are many toilets on the market today—including several recently introduced models—that achieve MaP test results of 800 and even 1,000 grams.

While just introduced in mid-2003, MaP testing is now widely employed throughout the toilet industry in the design and rating of toilets. “By 2004 we had the majority of manufacturers participating,” according to Koeller. To date, Veritec Consulting has carried out most of the third-party MaP testing, but the International Association of Plumbing and Mechanical Officials (IAPMO) is now also conducting MaP testing at its large Ontario, California laboratory—and they can accredit other laboratories to carry out MaP testing. The test protocol is also publicly available, so most of the major manufacturers use it in-house during toilet design making MaP testing the de facto basis for a significant number of new toilets in design. MaP testing has expanded beyond North America, too, with the three largest European toilet manufacturers now MaP testing their toilets, according to Koeller.

Even if the MaP performance data isn’t listed on product literature, nearly all toilet manufacturers will provide that information on request. MaP performance is also listed in the GreenSpec Directory (editor’s note: the Directory is published by BuildingGreen, which is a partner with McGraw-Hill Construction for GreenSource magazine). Information is also available in a frequently updated report, published by the California Urban Water Conservation Council. The 7th Edition of this report was released July 7, 2006.

For more information:
The most recent edition of “Maximum Performance (MaP) Testing of Popular Toilet Models” is available as a free download from the California Urban Water Conservation Council: http://www.cuwcc.org/MaPTesting.lasso

Koeller and Company
5962 Sandra Drive
Yorba Linda, CA 92886
714-777-2744

Veritec Consulting, Inc.
1495 Bonhill Road, #12
Mississauga, ON L5T 1M2 CANADA
905-696-9391

GreenSpec Product Directory
BuildingGreen, Inc.
122 Birge Street, Suite 30
Brattleboro, VT 05301
802-257-7300
www.buildinggreen.com

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