[en] Fuji Electric is working to develop methods for utilizing and monitoring radioactivity. In the monitoring field, Fuji Electric is developing and providing personal dose monitoring systems, survey meters and the like for use at newly constructed nuclear power plants and at an increasing number of worksites that use radiation. As personal dose monitoring systems, Fuji Electric provides a dose monitoring system capable of wireless real-time monitoring of doses detected with a semiconductor-based personal dosimeter, and a body surface monitor for use when entering or existing a radiation controlled area. Additionally, using a survey meter to measure the environmental radiation surrounding a radiation handling facility, and then sharing that data with local governments and disclosing it to the public, Fuji Electric also provides systems and survey meters for realizing safety and security for the local population. (author)

[en] The contamination monitoring is done by means of flat detectors, which are part of two detector walls. The detector walls are interlocked at an angle of 104⁰. Both the detector walls or columns have a vertical subdivision, which reduces the sensitivity of the arrangement at these places and therefore achieves an even measurement over the measurement cross section of the person to be monitored. (DG)

[en] The monitor has detector devices at an angle to each other made as a rigid component which can be rotated around a vertical axis in the angle between the joined detector devices. A reset drive which can be tensioned is provided at the axis of rotation. If it is in its rest position, a platform is situated as floor plate with a foot detector between the vertical detector devices. (orig./HP)

[en] The monitor has only two detector columns at an angle to one another and possibly divided in height, whose detectors are divided in the vertical direction in a middle range depending on a reference shape. The units formed by the subdivision equal the effect produced by the subdivision in approximation to the reference shape in evaluation. By including the detector columns divided into several detectors in height, a detector of about half the width is produced at a level above the threshold. Underarm boxes are provided at the outer edge of this detector, which are directed obliquely upwards. (orig./HP)

[en] There is a need for a personal dosimeter to measure the dose equivalent of newtrons from thermal to 15MeV. The authors have developed a combination dosimeter, which consists of TLD albedo dosimeter, newtron track film (NTA), and CR-39 carbonate track-etch dosimeter, for the purpose of evaluating wide energy range newtron dose-equivalent. This paper involves following: (1) The unfolding method of evaluating the dose-equivalent from measured data of the dosimeter using SAND-2 code. (2) The basic characteristics of the developed dosimeter when irradiated by ²⁴¹Am-Be source or TRIGA-2 nuclear reacter. (3) The comparison between evaluated dose-equivalent of the dosimeter and STUDVIK remcounter evaluated value. (4) The accuracy and sensitivity of this dosimeter. The next results are obtained: (1) The developed unfolding method is enough to evaluate wide energy dose-equivalent. (2) The measured spectrum and dose-equivalent is agreed with the BF₃ bonner counter evaluated one. (3) The accuracy is estimated within +-20%, and the sensitivity is enough satisfied the standard level of NRC and ANSI. (author)

[en] Among all the components required for radiation protection optimization, the evaluation of instrumentation is essential. The instrumentation in radiation protection allows to make the surveillance of personnel, installations and environment against the risk bound to radioactive contamination and ionizing radiations. The different devices can give the following functions: ambient dosimetry, (individual and environmental dosimetry), measurement of surface contaminations, air contamination by aerosols or gas, water contamination by liquid wastes,detection of criticality accidents, measurement of samples radioactivity. (N.C.)

[en] In Reports 39 (1985) und 43 (1988) the International Commission on Radiation Units and Measurements (ICRU) has proposed new operational quantities for environmental and individual monitoring in radiation protection. Extensive experimental and numerical studies performed at the PTB supporting the implementation of these quantities into the practice of radiation protection instrument calibration are described. Results of calculations of neutron fluence-to-dose equivalent conversion factors for various dose equivalent quantities and calculations and measurements of the responses of individual neutron monitors are discussed. (orig.)

[en] Specific radionuclide analyses are necessary for evaluating an environmental contamination and radiation exposure of population. Gross measurements - gross beta, gross alpha or gross gamma - are in most cases not appropriate to give the necessary information. In normal situations suitable analytical methods are available for gamma emitters just as well as for beta and alpha emitters. Refined equipment and skilled technicians are prerequisites. In situations like after the Chernobyl accident there is a lack of rapid methods for beta and alpha emitters. This has to be overcome by prompt analyses of the primarily contaminated media like air and precipitation. The methods developed should be considered reference methods and not standardized methods, i.e. they may be used as long as there are no alternatives that might be better suited. The descriptions of the methods should not only tell what to do, they should also tell why something is done. The provision of methods has to be supplemented by an appropriate program of quality control. Performance of measurement equipment and of analytical procedures should be regularly checked. Every laboratory should participate in intercomparisons as often as possible. Only the combination of suitable reference methods and of appropriate performance of these methods in the laboratories will ensure an optimum of information which is necessary to assess environmental contaminations. (orig./HP)

[en] This invention relates to a personal continuous air monitor capable of giving immediate warning of the presence of radioactivity. The monitor has a filter/detector head to be worn in the breathing zone of a user and it contains a filter mounted adjacent to radiation detectors, and a preamplifier. The filter/detector head is connected to a belt pack to be worn at the waist or on the back of a user. The belt pack contains a signal processor, batteries, a multichannel analyzer, a logic circuit, and an alarm. An air pump also is provided in the belt pack for pulling air through the filter/detector head by way of an air tube.d

[en] In post-accident situations where a release has resulted in the deposition of radioactive materials on the soil, it is essential to take contamination measurements immediately after the accident and throughout the recovery operations. A description is given of measurement equipment which has been developed in France for performing efficient measurements over large areas; it includes a gamma mapping device and an in situ gamma spectrometry system. These are compared and their use is described. (author). 3 figs, 1 tab