Going With the Flow--1.6 gpf Toilets That Work

Few efficiency standards have generated as many jokes and complaints as the 1.6 gallons per flush (6 liter) toilet requirement. The Energy Policy Act of 1992 required manufacturers to reduce the quantity of water per flush to 1.6 by 1994. Some say the industry was caught off guard and was given insufficient time to re-engineer their models, others say they not only had enough time, they should have seen the new standard coming (Massachusetts and California already had such a standard in place). In any event, the new requirement has been widely blamed for performance problems with some low-flow toilets. User unhappiness with toilet performance led to Congressman Joe Knollenberg (Republican – Michigan) sponsoring legislation to repeal the standard last year (see
EBN
Vol. 8, No. 9). So, are there low-flow toilets that work, and if so, how can they be identified? The answer is a resounding “yes” to the first question and “help is on the way” to the second.

The fluid dynamics are more critical at 1.6 gallons per flush (6 lpf) than at 3.5 gpf (13 lpf). All aspects of operation must work in concert for optimal performance.