Survey on thermal environments in bathrooms and elderly behavior while bathing in old residential buildings in Nanjing, China

¹ School of Architecture, Southeast University, 210000 Nanjing, Jiangsu Province, P.R. China
² Architecture Internationalization Demonstration School, Southeast University, 210000 Nanjing, Jiangsu Province, P.R. China

^* Corresponding author: hokoi@seu.edu.cn

Abstract

Bathing is a typical daily behavior among Chinese elderly people, which causes large thermal environmental fluctuations especially in winter. Rapid fluctuations of the thermal environment can lead to a drastic change in human blood pressure and may cause accidents while bathing. The most common style of Chinese bathing is showers. Information on the thermal environment during bathing is limited, making analysis difficult. This study aims to understand the current situation of bathing in old residences in Nanjing, China. To examine elderly bathing behaviors and thermal environments in bathrooms during bathing, we monitored the thermal environment in three elderly families and administered a questionnaire survey from which 49 responses were obtained. Results were categorized into environmental and personal factors that affect blood pressure during bathing. In winter, the temperature in a bathroom is often below 10℃. A heating device is installed close to the head (87%); thus, the thermal environment is vertically non-uniform (air temperature difference often exceeds 10℃). Most elderly individuals bathe for less than 30 minutes and the rise in air temperature often exceeds 10℃. This information will be used as the boundary conditions for thermo-physiological models that can quantitatively assess the impact of the environment on the elderly, and for the renovation of bathrooms.