Injury Prevention Policy
Tap Water Scalds
How big is the problem?
Hot water, including tap water in bathtubs and showers, is the leading cause of both scalds and hospital admissions for burns (1). Each year approximately 3,800 injuries and 34 deaths occur in the home due to scalding from excessively hot tap water. The majority of these injuries involve the elderly and children under the age of five (2). It takes less than 3 seconds to produce a partial-thickness burn when the water temperature is 145° F [63° C], but with a water temperature of 120° F [49° C] it would take much longer -- approximately 5 minutes (3). Since infants, young children and the elderly may not be able to respond quickly to a situation involving contact with hot water, a constant safe water temperature is essential for preventing scalds from tap water.
Policy and Details
States and communities shall enact and enforce building codes that require the installation of water heaters that keep tap water temperature at or below 120° F.
Tap water scalds can be prevented by lowering the water temperature at the source. To reduce the risk of scalds, water heater manufacturers have agreed to voluntary standards. The Gas Appliance Manufacturers Association, the trade organization for companies making gas-fired water heaters, directs all units to be preset at the factory to their lowest setting and have a dial marking or "detent" to indicate 120° F. The electric hot-water heater voluntary standard directs that the factory preset temperature not exceed 125° F (4). However, there have been no studies that examine compliance with this voluntary agreement and despite these standards, children are still being injured from tap water scalds. In addition, these standards do not prevent property owners, residents, water heater installers, plumbers and others from increasing the temperature setting once the heater is manufactured and distributed.
Legislation requiring a safe pre-set temperature for all water heaters has proven to be a more effective method of reducing scald burns than education to encourage parents to turn down water heaters. One study found that the implementation of a state law requiring water heater manufacturers to preset their products at a safe temperature (120 ° F) increased the number of homes with hot water temperatures less than 130° F when compared to educational programs alone. Almost all of the homes with water heaters installed after the law went into effect remained set at the lower temperature. This finding indicates that the lower water temperatures did not present other types of problems for consumers, such as not enough hot water or the inability to adequately clean clothes or dishes (7). These safe temperatures should be maintained through building code inspections to ensure that the hot water temperature setting for multi-family housing units are not increased.
David Lawrence, Center Director
1. Baker SB, et al. The Injury Fact Book: Second Edition. New York, New York; Oxford University Press, 1992.
Last modified: 3-August-2000.