Assessing the effectiveness of combined ventilation strategies for cooking in residential kitchens in Hong Kong

Abstract

Cooking activities are a major source of indoor air pollutants, including particulate matter (PM) and volatile organic compounds (VOCs), in residential buildings, and could impact occupants’ health and comfort. To enhance the understanding of IAQ in domestic kitchens, this study investigated the impacts of eight commonly used ventilation strategies (including the combinations of opening windows, opening doors, and using range hoods) during pan-frying, a prevalent cooking method in typical Hong Kong residences. Concentrations of CO2, TVOCs, and PM10 were measured and compared across different ventilation strategies. An IAQ index which integrated these indicators and their corresponding exposure limits was proposed to evaluate the ventilation effectiveness. The results revealed that the range hood was the most effective individual ventilation strategy, achieving the best IAQ index and highest ventilation rate. Combining multiple ventilation strategies could further enhance IAQ and is therefore recommended to meet practical ventilation needs. Importantly, significant interaction effects between the three ventilation strategies on IAQ were observed in both kitchen and living areas. Based on these findings, several practical suggestions were proposed, such as, using the range hood during cooking and keeping the kitchen door closed to minimize the transfer of pollutants to adjacent living areas. These insights contribute to a better understanding of ventilation effectiveness in Hong Kong’s residential kitchens and offer guidance for improving IAQ in small domestic settings.