[en] In the development these capacities it is necessary the aspects that can constitute performance indicators to evaluate the effectiveness work for regulatory authority in the execution their responsibilities as for the management accidents

[en] Ingestion of stable iodine (potassium iodide) offers an efficient protection against the irradiation of the thyroid when an accidental exposure to radioiodine occurs. This prophylaxis aims at obtaining a rapid and maximum thyroid protection without anti thyroid effects. The recommended posology is 100 mg of iodine in one time ( that is to say a tablet of 130 mg potassium iodide). After this single dose of iodine, the percentage of avoided radiation dose after 48 hours is near 75%, then decreases until 50% at 72 hours. It is possible to keep an efficient thyroid protection by taking a stable tablet of iodine on the first day, then a fourth of tablet the following days. This approach is an optimization allowing an efficient protection while reducing the eventual side effects linked to an excess of iodine. This protocol can be applied to adults, fifteen years or more adolescents, young adults and pregnant women. For children and babies there are not data to confirm the thyroid protection. The children constitute the most sensitize age group and this question should deserve to be thoroughly discussed. (N.C.)

[en] A selection of modern divers style watches were purchased and analysed for radioactive content. Those watches that were found to be radioactive were then tested to the international standard Radioluminescence for time measurement instruments specifications ISO 3157:1991. From the measurement results, the radiation exposures of people wearing radioluminous watches have been estimated and compared with the dose criteria specified in the consumer goods standards previously published by the Board. Twenty-two of the thirty-nine watches purchased were identified as being luminised with radioactive materials, the radionuclides involved being either tritium or promethium-147. Seven of these watches did not meet all the requirements of the ISO standard, due either to failure of luminised components under the adhesion test or to the presence of unprotected tritium paint on the watch bezel. This report found that the potential radiation doses do not exceed recommended levels. However, it was felt that for many of the products examined there was room for improvement. All manufacturers were contacted and asked what action they planned to take on the findings in this report. Manufacturers either confirmed that their products no longer used radioactive material or were being manufactured to comply with all international standards. The situation will be kept under review and levels of radioactivity in watches will be monitored. (author)

[en] Unit 1 of NAPS achieved first criticality on 12.3.1989 and Unit 2 achieved on 24.10.1991. Till the end of Feb-2000 these units have completed 1890 and 1811 full power days respectively. The performance of NAPS was expected to be better than the earlier Indian reactors in respect of safe production as well as cumulative radiation exposures. This is because of the major design improvements like: fully double containment system, elimination of ⁴¹Ar by introducing light water in calandria vault, reduction of core based fuel failure rate, separation of high radiation equipment to no occupancy areas during normal operation, a separate purification building for the purification of both moderator and PHT systems, a better layout of equipment and plant areas, elimination of unnecessary equipment in various systems besides ensuring the reliability of equipment for safe operation, selection of materials with low corrosion and activation characteristics etc. In this paper, the operational health physics experiences at NAPS to achieve ALARA exposures to plant personnel are described briefly. (author)

[en] No formal guideline exists on how to manage the patient with implanted pacemaker in Japan. We treated a patient not to receive the dose of 2 Gy to the pacemaker which is recommended in the ASTRO guideline. We could reduce the absorbed dose to the pacemaker below 2 Gy by the effort of several shielding techniques. (author)

[en] The Monte Carlo method is a tool from numeric dosimetry being used for the theoretical calculation of backscatter factors. This work aims to show and apply the method and give results attained determining backscatter factors for radiological diagnosis conditions

[en] We developed new suspension fluidized electro-polishing decontamination technique that the anodizing reaction electro-polishing reaction) progresses on the surface of object without electrical power input. Two electrodes are set in electrolyte that partitions by a porous membrane. After putting graphite particles into the positive side and flowing, take the polishing subject in the solution and input the electrical power. The etching effect is increased by adding a grinding material's particle or ultrasonic treatment. The radioactive substances in the materials or in the oxide layer on the surface of materials are dissolved and removed. The metal ions and radioactive elements reduce on the negative pole and change to metals. At the same time, positive graphite changes to neutral one. So that, neutral graphite can be used many times. The decontamination treatment of main structure materials in the atomic power plant was carried out. The residual activity was 0.03 Bq/g, from 3000 to 5000 or more DF, the marvelous values. This method can be applied to decontamination in the tube and the equipment far apart, industries, the dissolution method of plutonium and decontamination of radioactive contaminant metal waste in the nuclear facility. (S.Y.)

[en] The shielding of diagnostic x-rays in medical facilities is expected to be estimated according to effective dose based on the Enforcement Regulations of the Medical Service Law, which is to be amended in the near future. The method of calculation provided in this paper takes account of three types of radiation, primary, scatter, and leakage, for each radiation source, to estimate effective dose in the controlled area of a medical facility. X-ray data such as transmission, kerma in air, conversion factor, scatter fraction, and half-value layer were adjusted to estimate the shielding accurately. Estimations of x-ray shielding using effective dose were performed at our existing diagnostic x-ray facility as a model for a single x-ray tube and combined radiation resulting from multiple x-ray tubes. Effective doses estimated at the border of the controlled area ranged from 0.7 to 29.2 mSv per three months, meeting the effective dose limit defined by new the regulations of 1.3 mSv per three months. Results also indicated that exposure to combined radiation can be estimated. (author)

[en] In late years, if importance of mammography rises with increase of, cancer of the breast and introduces mammography into, cancer of the breast examination, I reach it. Several many inspection items are nominated for quality control of mammography. Reduction of quantity of being affected by exposure dose is made in those as an important item. This is because I may give excessive exposure dose so that mammography uses soft X-ray. I add some references consideration about the measurement of; half value layer and Average Glandular Dose in these studies and report it. (author)

No abstract available