Still Too Hot

Abstract

Objective Although water heater manufacturers adopted a voluntary standard in the 1980’s to pre-set thermostats on new water heaters to 120°F, tap water scald burns cause an estimated 1,500 hospital admissions and 100 deaths per year in the United States. This study reports on water temperatures in 976 urban homes and identifies water heater and household characteristics associated with having safe temperatures. Methods The temperature of the hot water, type and size of water heater, date of manufacture and the setting of the temperature gauge were recorded. Demographic data including number of people living in the home and home ownership were also recorded. Results Hot water temperature was unsafe in 41% of homes. Homeowners were more likely to have safer hot water temperature (≤ 120°F) than renters (63% vs. 54%; p<0.01). For 11% of gas water heaters, the water temperature was ≥ 130°F, although the gauge was set at less than 75% of its maximum setting. In a multivariate logistic regression, electric water heaters were more likely to have safe hot water temperatures than gas water heaters (OR=4.99; p<0.01). Water heaters with more gallons per person in the household were more likely to be at or below the recommended 120°F. Conclusions Our results suggest that hot water temperatures remain dangerously high for a substantial proportion of urban homes despite the adoption of voluntary standards to preset temperature settings by manufacturers. This research highlights the need for improved prevention strategies such as installing thermostatic mixing valves to ensure a safer temperature.

Addressing COVID-19 Misinformation on Social Media Preemptively and Responsively

“…Scientific evidence suggests that hot baths can minimally affect body temperature; studies have found a change of roughly 0.5°C –1.0°C in body temperature ( 11 , 12 ). Temperatures needed to deactivate coronavirus are typically >56°C ( 13 – 15 ), which exceed safe bath temperatures; scalding is likely within 10 minutes at 48°C ( 16 ). In other words, this graphic explains the science for why hot baths do not prevent COVID-19 and directly disputes the prevention efficacy of baths.…”

Some like it hot: Results of a community intervention trial aimed at improving safety behaviors to prevent hot water scald burns

“…Type of water heater, gallons per person and homeownership have been associated with safe hot water temperature in the literature. [14] Observations that were missing one or more variables were excluded from the regression.…”

“…Our previous work demonstrated that the availability of more hot water for each person (gallons per person) was associated with lower hot water temperatures. [14] Our study results are limited by it having been conducted as part of a community intervention trial, as opposed to a randomized controlled trial. Our hot water outcomes may be muted by our protocol to inform participants in both the standard and enhanced group when their water was too hot.…”

“…[13] Previous work has demonstrated an association between water temperature and the number of individuals in the home, size of water heater, homeowner status, and type of water heater. [14] Interventions to reduce hot water temperatures, mostly educational in nature, have been the focus of much previous research. A pooled analysis of 16 studies showed varying outcomes, but overall, families participating in the intervention arms were found to be more likely to have a discrete study-defined "safe hot water temperature", than families in the control arms (OR = 1.41, 95% CI [1.07, 1.86]).…”

Revisiting John Snow to Meet the Challenge of Nontuberculous Mycobacterial Lung Disease

“…These are critical observations in light of the ongoing debate regarding the most appropriate set-point for the household water heater for the prevention of scalding injuries [58]. For example, the U.S. Consumer Product Safety Commission recommends a manufacturer reduction in temperature set-point of 48.9 °C (120 °F) [59].…”