Hot water scalding is a major cause of burn injuries in the United States. Each year approximately 3,800 injuries and 34 deaths occur due to scalding from excessively hot tap water. Young children, older adults, and people with disabilities or special needs are more susceptible to hot water burns than the general population. Scald injuries are painful and can result in prolonged treatment, possible lifelong scarring, and even death.
Severity of scalding injuries is dependent on the time that skin is exposed to elevated water temperatures. Research has documented this relationship in Time/Temperature Charts. Based on this information, third-degree burns occur in adults when the skin is exposed to water at:
- 120-F for 5 min.
- 127-F for 1 min.
- 133-F for 15 sec.
- 140-F for 5 sec.
With this data, knowing the severity (degree) of the burn injury and the estimated time that skin was exposed to hot water, the temperature of the scalding water involved during an incident can be determined.
Hot water systems provide water for washing, bathing, cooking, and cleaning. Many things contribute to the final water temperatures from the plumbing hot water system, such as water heater settings, piping layout, valving, recirculation pumps, water usage, and other variables. A properly designed, installed, and maintained hot water system will deliver hot water at fixture outlets without placing the user at risk for hot water scalding.
Today’s plumbing codes and standards provide guidelines and requirements necessary to design and install safe hot water systems.