[en] Gamma spectrometric analyses of air and other environmental samples from PINSTECH were carried out. Air particulate samples were analyzed by a Ge(Li) detector on a computer-based multichannel analyzer. Other environmental samples were analyzed by a Na(T1) scintillation detector spectrometer and a multichannel analyzer with manual analysis. Concentration of radionuclides in the media was determined and the sources of their production were identified. Age of the fall out was estimated from the ratios of the fission products. (authors)

[en] Radiometric analysis of lunch served at PINSTECH cafeteria was carried out during the period from 1976 to 1984 by NaI (TI) scintillation detector, high resolution Ge(Li) detector gamma spectrometry system and low level beta counter. K-40 and Sr-90 were the most prominent radionuclides normally detected in all the lunch samples. Other radionuclides were below the measurement limits of our counting set up. Assuming 5 days a week and 50 weeks a year it can be safely stated that intake of K-40 and Sr-90 through LUNCH taken at PINSTECH cafeteria remains well below respective ALI's of these radionuclides. (author)

[en] The paper describes some counting facilities available in low-level environmental surveillance laboratory at PINSTECH. Radioactive measurement techniques for the environmental media such as air-particulates, rain and surface waters, vegetables and other food items with low radioactivity concentration are described with particular reference to the lower limit of detection possible with the counting set-ups described. Air-particulates with complex gamma spectra were analysed by a high-resolution Ge(Li) detector and a computer-based multichannel analyser from Canberra Industries. Other samples with simple spectra were analysed by a NaI(Tl) scintillation detector. The better resolution of the Ge(Li) detector more than compensated for its lower efficiency with respect to the NaI(Tl) detector regarding analysis of complex gamma spectra. The background of the gamma spectrometry set-up was reduced by 8-cm lead shielding lined internally with 8-mm copper; the latter was used to remove the low-energy peak due to X-rays from lead. The system was capable of measuring gamma activity lower than 1.85 Bq, corresponding to a concentration of radioactivity in air of about 2.74x10^-5 Bq/m³ for a counting period of 100 min. The background of the beta set-up was reduced by aged lead shielding and anticoincidence circuitry. The lowest beta activity measured by this counting set-up was about 9.31x10^-7 Bq/m³ in air for ⁹⁰Sr and 8.16x10^-7 Bq/m³ for ¹³⁷Cs. Beta counting of ¹³⁷Cs afforded a 100-fold increase in sensitivity over gamma counting. Low-level tritium in aqueous samples was measured by a Packard Model 3320 liquid scintillation spectrometer. The instrument has a low background due to cooling of the photomultipliers and coincidence technique. The minimum activity of tritium measured for a 50-min counting period ranged from 0.5 to 1.0x10^-2 Bq/ml, corresponding to 50-100 tritium units (TU). (author)

[en] A plan for handling of the radiation emergency situation prevailing outside PINSTECH has been incorporated in this report. This report outlines the detailed procedures and collective responsibilities and actions to be undertaken for meeting the emergency situation. These procedures include announcement/notification of emergency, evaluation of emergency, control of access and aggress, personnel monitoring and internal dosimetry, medical care of injured etc. A summary of the role and responsibilities of PINSTECH and the public organisations during a sector emergency at PINSTECH has been included as an appendix. (Orig./A.B.)