Extensive testing on 49 of the most popular toilets in the United States resulted in a performance report by the NAHB Research Center in cooperation with Seattle Public Utilities and the East Bay Municipal Utility District (EBMUD) of Oakland, Calif.
The objective of the report "Summary Test Report: Water Closet Performance Testing" was to develop information on product performance, water savings reliability and physical characteristics that will assist consumers in evaluating products and making purchase choices.