Conference Agenda

A floor heating system offers a highly comfortable living environment by providing an optimal temperature distribution keeping the air cooler around the head while maintaining warmth at the feet. Previous studies on thermal comfort suggest that the floor heating system enables direct warmth through thermal radiation, which can lead to discomfort when used for long-term. Therefore, it is necessary to evaluate the thermal sensation of floor heating system with focusing the thermal sensation and energy consumption on time dependence. In this study, with using the composition of floor materials and underfloor materials for floor heating system, the long-term measurements focusing on the relationship between thermal properties and power consumption, and the subject experiments on thermal sensation evaluation was performed. The tatami and wooden flooring were used in this experiment. We will report that the relationship between the psychological evaluation of thermal sensation, comfort, etc. of 10 subjects and the thermal properties of floor heating, such as power consumption, surface temperature, and contact temperature, when the composition of floor materials and underfloor materials was rearranged in the traditional Japanese lifestyle of sitting on the floor. As a result, although the surface temperature of tatami is about 2 to 2.5 K lower than that of wooden flooring, it leads to energy savings of about 5 to 10%. At this time, there was no difference in the contact temperature of the buttocks in contact with the flooring material, and the thermal sensation tended to be higher with tatami, revealing differences in thermal sensation and energy saving due to the different constituent materials.

Office space is the place where the employees spend most of their day, and it is known that the office environment affects their psychology and physiology. It has been pointed out that various factors in offices, such as noise, indoor air quality, lighting, and seating position, exert stress on employees, causing them to work less efficiently and to leave their jobs. As a countermeasure, for example, in 2014, Delos Corporation began operating the WELL Building Standard certification system, as a workspace evaluation system for office. In this certification, the office environments are considered as a big factor that affects the mental and physical health of employees. Among these environments, the importance of planting has been attracting attention, and it can be said that the effects of planting in offices on the psychology and physiology of employees will be considered important. Previous studies have shown that indoor planting offers air purification and visual healing effects, contributing to the reduction of employees' stress. Therefore, number of companies are incorporating planting in their offices in consideration of the impact of the office environment on employee psychology and physiology. Although there are several studies on planting arrangements in office spaces, only few have evaluated the effects of their layout conditions on office workers' impressions. In this study, the relationship between the arrangement of plantings in office space and the subjects' sensation were examined using Sandplay therapy. The outcome of this study can contribute to the proposal for an effective arrangement of plantings for reducing employees' stress and for efficient work when indoor greening is implemented in office spaces.

Portable air cleaners (PACs) are simple appliances that can be used to reduce indoor concentrations of fine particulate matter (PM2.5). However, PAC performance, measured by absolute and relative reductions in PM2.5 concentration, can vary considerably in real environments. To understand the extent that performance is influenced by user behaviour, a three-arm randomized crossover trial testing PACs was conducted in 60 apartments in three neighbouring buildings in Toronto, Canada. PACs operated under one of three conditions (placebo, constant filtration, and automated) for each one-week study arm. Particulate matter (PM) concentrations were measured continuously using PurpleAir sensors. Weekly surveys were used to estimate the frequency of specific behaviours that may affect PM2.5 concentrations during each study arm. Larger absolute reductions were consistently observed in homes with relatively high indoor PM2.5 concentrations during the placebo arm. Relative reductions were less consistent, although frequently greater in homes with lower average concentrations. Similar results were observed during the automation arm. The variation in PM2.5 concentrations within and between homes can be attributed to at least three of the behavioural factors evaluated by the survey: smoking; use of incense, candles, and essential oil diffusers; and opening the balcony door. Future intervention studies should therefore make efforts to track these and other behavioural factors, as well as environmental factors that can affect indoor PM2.5 concentrations, as these may provide context for evaluating PAC performance as well as information that may be helpful in any assessment of health outcomes.