When bathing an infant, put cold water in first and then mix in hot, and test it with the inside of the wrist or the elbow before putting the child in; if the water heater can set the outlet temperature, set it below 50 °C

Hot water at 65 °C, in contact for 2 seconds, gives most adults a 3rd-degree burn, and an infant's skin is thinner. Put cold water in the basin first, then mix in hot. Stir it even, test it with the inside of the wrist or the elbow, and only then put the child in. Do not wash the child under a running tap. After 1 US state lowered the factory outlet temperature of water heaters to 49 °C, hospital admissions of children for hot-water burns fell by more than 1/2.

Cost

No money. Each bath takes 1 or 2 extra minutes to test the water. If you want it steadier, you can buy a water thermometer. The hard part is still testing before you put the child in, even when the child is crying and the adult is in a hurry.

Benefit

The US Consumer Product Safety Commission says most adults get a 3rd-degree burn from 2 seconds in water at 150 °F (about 65 °C). Water at 140 °F (60 °C) for 6 seconds, or water at 130 °F (about 54 °C) for 30 seconds, also scalds. Even at 120 °F (49 °C), a soak of 5 minutes can still cause a 3rd-degree burn. A World Health Organization report says the skin of infants and young children is thinner than an adult's, so a lower temperature can scald, and the scald goes deeper. The American Academy of Pediatrics teaches parents to test the water in the basin with the inside of the wrist or the elbow, and that it should be "warm, not hot." "Never bathe a baby under running water," because water moving through the pipes swings hot and cold, and a small change can scald. In 1983 the US state of Washington passed a law that new water heaters leave the factory preset at 49 °C. By 1988, the average home hot-water temperature had fallen from 61 °C in 1977 to 50 °C. Hospital admissions of children for tap-water burns fell from 5.5 a year in the 70s to 2.4 a year. Burned area, skin grafts, deaths, and days in hospital all fell too. That is a before-and-after comparison, not a trial that split people into groups. Australia sets a maximum of 50 °C for bathroom hot-water taps. In New South Wales from 1989 to 1996, the rate of hospital admission for burns among children aged 0 to 4 fell by 13%. Severe burns, those with a hospital stay of 10 days or more, fell by 30% in the 2 years after the 2nd stage. In 3 Chinese hospital series of childhood burns, scalds from hot liquid accounted for 87.6% to 90.6%, and children under 3 years were the largest share.

Notes

The grade is B because the figures come from before-and-after comparisons and from case records, with no trial that split people into groups. The benefit is set at medium by judgment, because a separate domestic figure for bath-water burns was not found. Water heaters come in 2 kinds. An instantaneous heater, such as a gas water heater, has its outlet temperature set directly below 50 °C. A storage electric water heater is a separate case. The World Health Organization guide on preventing Legionella suggests keeping the heater outlet at 60 °C, and hot water at the tap no lower than 50 °C. Legionella is a bacterium that can cause pneumonia. The same guide also says that preventing Legionella must not raise the risk of a child being scalded, and a thermostatic mixing valve can be fitted at the outlet. If none is fitted, rely on cold first, then hot, and on testing before you put the child in. Do not walk away during the bath. The American Academy of Pediatrics says more than 1/2 of children who drown in a bathtub are under 1 year of age. See Section 1, item 12 (stay in sight near water). Do not carry hot water or hot soup while you are holding the child. The World Health Organization says that in high-income countries, the most common burn in an infant under 1 year of age is a scald from a hot drink in a cup. If the child is burned, run cool water first. See Section 13, item 14 (run cool water after a burn).

Sources · 9

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