Field investigation of lifestyle and indoor environment with COVID-19 in facilities for older adults in cold regions of Japan

The emergence of COVID-19 clusters for older adults has been increasing recently in Japan. Facility staff control cross-ventilation with open windows as the primary measure against COVID-19 in facilities for older adults. In this study, the indoor thermal environment, lifestyle, ventilation method, and other in six facilities for older adults were investigated to understand how facility operation management has changed since the spread of COVID-19. As a result, the indoor air temperature was well-managed in all facilities during both seasons. However, the wet bulb globe temperature was measured above the warning level of 25 °C due to the influence of high indoor humidity in summer. The humidity in the facilities was always controlled under low-humidity conditions during winter. In the lifestyle investigation, many votes suggested that the staff found wearing masks uncomfortable. Most older adults were not wearing masks because it made them feel stuffy. Moreover, the staff opened windows for cross-ventilation without relying on objective judgment. Thus, if effective ventilation is not performed, the ventilation efficiency in the facility deteriorates and raises further infection risks. Therefore, staff in facilities should be maintained appropriate indoor carbon dioxide concentrations by ventilation during the COVID-19 catastrophe.