Impact assessment of mandatory safety device installation for gas stoves

Numerous fire accidents have occurred in Japan owing to food overheating when cooking on gas stoves because users left the cooking area unattended. In response, authorities enacted a legal revision mandating temperature sensor installation on gas stove burners. Nevertheless, the actual effectiveness of this measure remains uncertain. Furthermore, prior studies have raised concerns about the efficacy of specific safety standards for consumer products owing to insufficient evidence of reduction in accidents. Consequently, this study seeks to assess the impact of the standards revision implemented in 2008, requiring the placement of safety devices on all gas stove burners. Through a comprehensive analysis, it was aimed to ascertain how these measures have precisely influenced safety outcomes in cooking-related incidents. The data in this study were subdivided to mitigate potential bias from user attributes during data collection. The analysis employed the difference-in-differences method, specifically utilizing one-burner gas stoves unaffected by the standards revision. The data used in this study include accidents associated with gas stoves, spanning the period 2007-2019. To estimate the likelihood of overheating accidents, a binomial distribution model that utilized the Markov chain Monte Carlo methods was applied. For gas stoves with two or more burners, which were affected by the standards revision, the estimated probability of overheating accidents decreased by approximately 80%. In contrast, no decreasing trend was observed for one-burner gas stoves. The analysis suggests that the mandatory installation of safety devices on gas stoves has indeed resulted in a significant reduction in overheating accidents.