Yumiko Nagai

In a pilot study, we observed the state of "heat shock" in elderly persons living in Osaka and Akita by means of simulating bathing and excretion in winter. Furthermore, using data on indoor thermal environments collected nationwide, we investigated relationships between heating equipment and air temperature in bathrooms and toilets, temperature differences from living rooms, and thermal sensations for the elderly. The pilot study showed that differences in air temperature between living rooms and other rooms were larger in cold latitudes, where there was a subject with remarkably increased blood pressure when moving from the living room to the bathroom or the toilet. According to data from our nationwide survey, temperature differences between living rooms and bathrooms or toilets were the highest around eight o'clock in the evening. Despite similar thermal sensations, actual air temperatures in bathrooms and toilets were lower than those in living rooms. Elderly persons seemed to be tolerant to cold in bathrooms and toilets, although they might be stressed physically. Differences in temperature between living and bathrooms have a tendency to correlate with death rates from bathing.

A survey on thermal conditions of houses was carried out on 331 houses in 11 regions (Sapporo, Akita, Sendai, Chiba(north), Chiba(south), Shizuoka, Toyama, Osaka, Hiroshima, Fukuoka and Kagoshima) from December, 2004 to March, 2005. The air temperatures in the living room, bathroom, dressing room, toilet, corridor, bedroom and outdoor of houses were measured evety minute for 7 days. The water temperatures of bath during bathing were also recorded. The thermo-recorders which measured air temperatures at a height of 0.6-1.1m were kept out of the sun. The following results were obtained. (1) The room temperatures in Sapporo were kept above 15℃ in all rooms in winter. On the other hand, only living rooms were kept warm in the rest of regions. (2)The room temperatures in dressing rooms and/or corridors were vety low in all regions, except in Sapporo, (3)The mortality rate ofdrowninginthe 11 regions was correlated withthe room temperature in the dressing room.