174 Hood performance in removing NO2 from natural gas cooking in eight Taiwanese households

The emissions from cooking with a gas stove are harmful to human health, among which NO2 has been linked to an increased risk of asthma incidence. The use of kitchen hoods has been an effective solution to mitigate exposure to cooking emissions; however, information on their performance in Taiwanese households was extremely limited. This study aimed to evaluate hood performance in removing NO2 in eight Taiwanese households, using two kitchen hoods with distinct laboratory performance. We recruited eight Taiwanese houses and conducted repeated, 3-day integrated sampling for NO2 in kitchens, living rooms, and balconies for two months per home. Two kitchen hoods with distinct performance in the laboratory tests were chosen to undergo two consecutive 4-week sampling. In the second week of each hood test, we designed a recipe-control week to ensure all the ingredients and the way of cooking for each household were in comparable conditions. Additionally, the time-activity data were collected to account for cooking activities and potential pollutant sources. Our results showed that using different kitchen hoods impacted NO2 concentrations in the same household. However, when using the same hood, the NO2 concentration differed by cooking activities across different homes, even in the recipe-control weeks. No significant, consistent difference was found between the hoods using NO2 as the indicator, suggesting that environmental factors played an important role in influencing hood performance. Findings from this study provide insights for evaluating the hood performance in Taiwanese houses with different cooking activities and other factors in the future.