Identifying key factors influencing Cook's thermal comfort in Chinese-style residential kitchen based on typical cooking methods

Cooks in Chinese-style residential kitchens (CRKs) often experience unsatisfactory thermal comfort. Different cooking methods lead to different thermal conditions and different metabolic activity, yet their specific impact on cooks' thermal comfort has not been fully investigated. To address this gap, we combined a nationwide survey across China (n=357), field studies in 12 cities, and controlled laboratory experiments. Steaming/boiling (S&B) and stir-frying (SF) were identified as the dominant cooking methods in Chinese homes. Field measurements revealed cooking activities increased ambient air temperature by approximately 2.5 °C compared to non-cooking periods. Laboratory experiments demonstrated that while SF resulted in lower ambient temperatures and higher relative humidity than S&B, cooks reported feeling hotter during SF due to the continuous movement required and greater upper-body heat exposure. Key factors influencing cook's thermal sensation vote (TSV) including air temperature, radiant temperature, relative humidity at different heights varied depending on the cooking method. Using these parameters as inputs, we developed Random Forest regression models that achieved validation accuracies exceeding 0.7 in real-world settings. To improve thermal comfort, we recommend reducing air temperature at 1.7m for S&B and lowering radiant temperature for SF. This study advances thermal comfort research by investigating the combined effects of cooking methods, thermal environment, and behavioral patterns. Our non-intrusive prediction approach requires only environmental measurements, providing practical strategies for improving kitchen design and ventilation systems.