A low-flush toilet or low-flow toilet is a flush toilet that uses significantly less water than a full-flush toilet. Most low-flush toilets use 6 liters (1.6 gallons) per flush as opposed to the usual 13.2 liters (about 3.5 gallons). They came into use in the United States in the 1990s, citing water conservation concerns. Many dual flush toilets have a 6 litre and a lower flush. In 1992 President George H. W. Bush signed the Energy Policy Act.