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The 3-11 Earthquake occurred in Japan last year had greatly damaged the lives and properties and also caused the core meltdown accident in the Fukushima nuclear power plant followed by the leakage of radioactive materials into biosphere. In order to protect against the detriment of radiation from foods which were imported from Japan, the Institute of Nuclear Energy Research (INER) in Taiwan started to conduct radioactivity inspection of food products from Japan after the accident. A total of about 20,000 samples had been tested from March 24 2011 to March 31 2012., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The nuclear facilities at Institute of Nuclear Energy Research (INER) had been successively decommissioned and decontaminated over the recent years. Since dismantling was a complex task, to achieve the main goal was minimization of radioactive waste production and required the set-up of procedures, criteria of free release, strict follow-up and traceability at all steps. This study gave an overview of the efforts on non-destructive assay (NDA) of relatively large volumes of waste and the sampling of contaminated waste with radiochemical analysis was utilized to determine the radionuclide vectors. The experiences of free release planning and measurement of a very low level radioactivity with high throughput for scrapped metal at the INER and the technical achievements in this research could offer a reference of decision-making by the competent authority.

An alpha/beta emitter measurement system used to calibrate surface sources following the guidelines of ISO 8769 has been established in Institute of Nuclear Energy Research (INER) around the year 2000. This system consists of a windowless proportional counter with a uniformity of 0.28% when measuring the emission rate of a source on a centered area of 100 mm x 150 mm, and a uniformity of 0.62% when the source area was 150 mm x 200 mm. Four 100 mm x 150 mm sources (90Sr + 90Y, 36Cl, 14C and 241Am) had been measured by this system. The measurement results of the above four sources when compared with those of National Physical Laboratory, UK (NPL) showed difference between the two laboratories of < 1%.