The majority of injuries and deaths involving tap water scalds are to the elderly and children under the age of five. The U.S. Consumer Product Safety Commission (CPSC) urges all users to lower their water heaters to 120 degrees Fahrenheit. In addition to preventing accidents, this decrease in temperature will conserve energy and save money.
Most adults will suffer third-degree burns if exposed to 150-degree water for two seconds. Burns will also occur with a six-second exposure to 140-degree water or with a thirty-second exposure to 130-degree water. Even if the temperature is 120 degrees, a five-minute exposure could result in third-degree burns. Various procedures for lowering water temperature in the home exist, depending on the method of heating. Here are some suggestions:
Electric water heaters. Hot water should not be used for at least two hours prior to setting. To make the adjustment yourself, start by shutting off current to the water heater, then turn off the circuit breaker to the heater or remove the fuse that serves the heater. Most electric water heaters have two thermostats, both of which must be set to a common temperature for proper operation. To reach these thermostats you must remove the upper and lower access panels. Adjust the thermostat following the instructions provided with the appliance. Hold a candy or meat thermometer under the faucet to check the water temperature.
Gas water heaters. Where precise temperatures are not given, hold a candy or meat thermometer under faucet for most accurate reading first thing in the morning or at least two hours after water use. If reading is too high, adjust the thermostat on the heater, according to the manufacturer’s instructions, and check again with thermometer.
Furnace heater. If you do not have an electric, gas, or oil-fired water heater, you probably have an on-line hot water system. Contact your fuel supplier to have the temperature lowered. If you live in an apartment, contact the building manager to discuss possible options for lowering your tap water temperature. Reducing water temperature will not affect the heating capacity of the furnace.
CPSC notes that a thermostat setting of 120 degrees Fahrenheit (49 degrees Celsius) may be necessary for residential water heaters to reduce or eliminate the risk of most tap water scald injuries. Consumers should consider lowering the thermostat to the lowest settings that will satisfy hot water needs for all clothing and dishwashing machines.
Never take hot water temperature for granted. Always hand-test before using, especially when bathing infants and young children. Leaving a child unsupervised in the bathroom, even if only for a second, could cause serious injuries. Your presence at all times is the best defense against accidents and scalding to infants and young children.
U.S. Consumer Product Safety Commission