The current study was performed to investigate the influence of high temperature on the value of radiation dose measured by optically stimulated liminescence (OSL) dosimeter or radio photo luminescence (RPL) dosimeter (glass dosimeter) . Serial measurements of temperature in the car confirmed that it can rise to 80°C or higher in the area irradiated with sun beam. The relationship between the temperature and the radio dose measured by X-ray irradiated OSL dosimeter or glass dosimeter under the condition from 50°C to 90°C after the set of 3h. to 72h. The value measured by OSL dosimeter tended to be lower with higher temperature or longer setting time. On the other hand, those factors did not influence the value measured by glass dosimeter.
Tritium concentrations in river water have been measured at Toki area (Toki-shi, Gifu-ken, Japan) since 1982. The tritium concentrations decreased exponentially, and their apparent half-lives were distributed between 2.3 and 7.2 year. It is suggested that the time during which rainwater changes to groundwater and is discharged again as river water is different at spot by spot. As a result of comparison with yearly variations of flow rate, a inverse correlation was recognized between tritium concentration and flow rate in some spots.