Abstract
Recent amendments to the Law concerning Prevention of Radiation Hazards due to Radioisotopes, etc. and related regulations might afford the use of unsealed radioisotopes below the exemption limits outside controlled areas. This drastic change brought a great convenience to radiation workers, however, the practical management should take safety of both non-radiation workers and environments into consideration. Analysis of research activities using unsealed radioisotopes and a survey for radiation workers in Nagasaki University revealed that a number of biochemical experiments could be performed using radioisotopes below the exemption limits and that a half of respondents desired to use them in their own laboratories. Radiation safety management of those areas was also favored by most of responders, which would increase tasks of radiation safety staffs. Therefore, the rational and affordable safety management practice is required. On the basis of these results together with radiation safety managements in the U. S., Canada and the U. K., practical considerations for the use of radioisotopes outside controlled areas in Japan are discussed.
