Toilets (Tank Type and Flush Valve)

Toilet fixture replacement has been a staple of the water industry’s initiatives to reduce potable water consumption since the late 1980s. It still represents one of today’s most popular water efficiency initiatives, as the first “program of choice” by water providers embarking on their initial foray into hardware-related conservation. In these programs, older 3.5- and 5.0-gallons per flush (gpf) [13 litres per flush (Lpf) and 19 Lpf] toilet fixtures in residences are replaced with 1.6-gpf (6 Lpf) or 1.28-gpf (4.8 Lpf) fixtures. Today, some water providers with aggressive replacement programs are already approaching a level of “saturation” in their residential and commercial sectors wherein the majority of toilet fixtures are the efficient models. Therefore, a number of water providers have moved on to other more efficient products and higher priorities in their conservation programs. However, a study completed by AWE in 2017 of five states found that surprisingly high levels of inefficient toilet stock still remain.

Two distinct types of toilet fixtures dominate the marketplace today: ULFTs (Ultra-Low Flush Toilets – aka “low flow” or “ultra-low-flow”) and HETs (High-Efficiency Toilets). ULFTs are defined by an effective flush volume in the range between 1.28-gpf and 1.6-gpf (4.8 Lpf and 6.0 Lpf), while HETs are defined as 1.28-gpf (4.8 Lpf) or less. View the prevalence of HETs in the North American marketplace here. 

Maximum Performance (MaP) Testing. Many toilet fixture performance tests exist, including proprietary tests by the fixture manufacturers, tests by Consumer Reports magazine, and the tests mandated by the plumbing codes for fixture certification. Few of these, however, use test media that closely resembles the real "demands" upon a toilet, i.e., that of human waste.

The Maximum Performance (MaP)  testing project was developed in 2003 in order to identify how well popular toilet models perform using a realistic test media. The testing protocol, cooperatively developed by water-efficiency and plumbing fixture specialists in the U.S. and Canada, incorporated the use of soybean paste as a test media, closely replicating the "real world demand" upon fixtures. Since 2003, the current MaP lists provide performance information on over 4,500 different tank-type toilet fixture models and commercial flushometer type fixtures by over 200 brands.