Establishing a mobile environmental survey system for real-time emergency response.

After the 9/11 incident, the needs of environmental survey mobility were increased because the time and place of terrorism attacks are more unpredictable than traditional radiological and nuclear accident. In recent years, more and more attention has been paid to the radiation protection of the survey workers in the field. The Institute of Nuclear Energy Research has established a Mobile Environmental Survey System (MESS) for real time emergency response by using network communication.

Air kerma standard and measurement comparison on source strength determination for high-dose rate 192Ir brachytherapy in Taiwan.

This paper describes the establishment by the Institute of Nuclear Energy Research (INER, Taiwan) of the reference air kerma rate (RAKR) calibration standard for measurement of high-dose rate (HDR) (192)Ir brachytherapy source strength. A bilateral comparison has been made in the RAKR standards for HDR (192)Ir brachytherapy sources at the INER and Physikalisch-Technische Bundesanstalt (PTB, Germany) and the measurement difference was within the overall standard uncertainty and showed good agreement between the two calibration standard systems established at the INER and the PTB. Besides, INER also worked with 20 domestic hospitals to organise an on-site measurement comparison programme to explore the status of HDR (192)Ir brachytherapy source strength determination in Taiwan.

Proficiency testing feasibility study for the measurement of gamma-emitting clearance samples.

A proficiency testing feasibility study program was proposed by the National Radiation Standard Laboratory (NRSL) of Taiwan to understand the capabilities of laboratories dealing with clearance measurements, and to issue related technical criteria for radioactive waste assay. In this program, twelve blind test samples with different levels of radioactivity, radionuclides and different packing densities were prepared. Seven laboratories participated in this program and fourteen instruments were tested.

Development of improved free-air ionisation chamber as absolute dosimetry standard for low-energy X rays in INER.

The National Radiation Standard Laboratory of the Institute of Nuclear Energy Research (INER) designed and constructed an improved Attix style free-air ionisation chamber (FAC) for low-energy X-ray measurements. Clinically, X rays in this energy range are used in mammography radiology. This chamber is also used to perform air-kerma measurements.

Dosimetry study for beta-radiation treatment of in-stent restenosis.

Intravascular brachytherapy (IVBT) has been recognised as a treatment modality for reducing coronary restenosis after angioplasty and stent-implantation procedures. For the treatment of in-stent restenosis using beta-emitter (188)Re, delivering adequate doses to the entire vessel wall is not possible without the potential of overdosing tissues. A method to measure the dose distribution, perturbation and percentage depth dose using plane-parallel and cylindrical tissue-equivalent phantoms has been developed.

Clearance measurement of metal scraps for nuclear facility at INER in Taiwan.

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 calibration and evaluation of a radioactive waste drum counting system.

The drum counting system was calibrated in this study. For (137)Cs, the counting efficiencies were around 14-1% when the density of the waste of the drum was changed from 0.15 to 2.

Primary standardization of (67)Ga radiopharmaceuticals.

The two-dimensional extrapolation technique and dead time extrapolation technique of 4pibeta-gamma-coincidence counting were used to standardize the activity of (67)Ga. The counting results of the two absolute counting techniques showed good agreement while the two-dimensional extrapolation technique could save about 50% of the total counting time in this study. The accuracy of the Capintec CRC-15R radionuclide calibrator used by the radiopharmacy of INER was studied in this research.

Reevaluation of the emergency planning zone for nuclear power plants in Taiwan using MACCS2 code.

According to government regulations, the emergency planning zone (EPZ) of a nuclear power plant (NPP) must be designated before operation and reevaluated every 5 years. Corresponding emergency response planning (ERP) has to be made in advance to guarantee that all necessary resources are available under accidental releases of radioisotope. In this study, the EPZ for each of the three operating NPPs, Chinshan, Kuosheng, and Maanshan, in Taiwan was reevaluated using the MELCOR Accident Consequence Code System 2 (MACCS2) developed by Sandia National Laboratory.

Sequential isotopic determination of plutonium, thorium, americium, strontium and uranium in environmental and bioassay samples.

A procedure has been developed to provide sequential analysis of 238Pu, 230Th, 241Am, 238U, and 90Sr in environmental and bioassay samples. Tracers and/or carriers (242Pu, 243Am, 232U, and stable strontium) are added into the sample as chemical yield monitors, and then, plutonium, thorium, strontium, americium, and uranium are sequentially separated and purified by Dowex ion-exchange resin, EiChroM Sr-resin, EiChroM TRU-resin, and Chelate-100 resin, respectively. The radioactivities of 90Sr and the actinides are measured using the liquid scintillation counter and alpha-particle spectrometer, respectively.