Health physics in JAERI, no.28

In the annual report No.28 (fiscal 1985) are described the activities of health physics including radioactive waste management in Tokai Research Establishment, Takasaki Radiation Chemistry Research Establishment and Oarai Research Establishment. There were no occupational exposure exceeding the maximum permissible dose and no release of radioactive gaseous and liquid waste beyond the release limit specified according to the regulations. In the environment there were observed no abnormal radioactivity due to facilities. Technology development and research; Technology developments were made as in the previous years for improving the techniques and methods in monitoring of individuals, facilities and environment, radiation measurement instrumentation and also in waste management and decontamination. The following works were made in the researches of radiation dosimetry, body radioactivity, airborne radioactivity and estimation of radiation dose due to low level waste disposal. For radiation dosimetry: portable apparatus for calibration of radioactive gas monitors, evaluation of β-ray depth dose distribution, and exposure analysis through an extended series of specific jobs at JRR-2. For body radioactivity: characteristic of JAERI phantom for an assessment of Pu in lung, transfer compartment in the internal dose evaluation method, and radiosensitivity of chromosomes of rabbit lymphocytes. For airborne radioactivity and estimation of radiation dose due to wastedisposal: sheltering effect of houses for radioactive effluent, tritium oxide permeability of membrance in protective appliances, conversion rate of low concentration tritium gas to tritiated water, computer code for calculation of radiation dose from very low-level radioactive waste disposal and safety demonstration tests of national disposal of very low-level radioactive solid waste. (J.P.N.)