NOTE The report of the Committee without its annexes appears as Official Records of the General Assembly, Sixty-third Session, Supplement No. 46. The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Secretariat of the United Nations concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The country names used in this document are, in most cases, those that were in use at the time the data were collected or the text prepared. In other cases, however, the names have been updated, where this was possible and appropriate, to reflect political changes. Scientific Annexes Annex A. Medical radiation exposures Annex B. Exposures of the public and workers from various sources of radiation INTROdUCTION 1. In the course of the research and development for and the application of atomic energy and nuclear technologies, a number of radiation accidents have occurred. Some of these accidents have resulted in significant health effects and occasionally in fatal outcomes. The application of technologies that make use of radiation is increasingly widespread around the world. Millions of people have occupations related to the use of radiation, and hundreds of millions of individuals benefit from these uses. Facilities using intense radiation sources for energy production and for purposes such as radiotherapy, sterilization of products, preservation of foodstuffs and gamma radiography require special care in the design and operation of equipment to avoid radiation injury to workers or to the public. Experience has shown that such technology is generally used safely, but on occasion controls have been circumvented and serious radiation accidents have ensued. 2. Reviews of radiation exposures from accidents have been presented in previous UNSCEAR reports. The last report containing an exclusive chapter on exposures from accidents was the UNSCEAR 1993 Report [U6]. 3. This annex is aimed at providing a sound basis for conclusions regarding the number of significant radiation accidents that have occurred, the corresponding levels of radiation exposures and numbers of deaths and injuries, and the general trends for various practices. Its conclusions are to be seen in the context of the Committee's overall evaluations of the levels and effects of exposure to ionizing radiation. 4. The Committee's evaluations of public, occupational and medical diagnostic exposures are mostly concerned with chronic exposures of …

sources and effects of ionizing radiation

Optically Stimulated Luminescence (OSL) dating allows age determination of sediments deposited during the last glacial-interglacial cycle. This relatively new technique therefore enables chronological frameworks to be established for fluvial deposits that often cannot be dated by other means. The OSL signal of quartz and feldspar minerals is reset by light exposure during fluvial transport, and builds up as a result of ionizing radiation after burial of the minerals. Incomplete resetting of the OSL signal because of inadequate light exposure in the fluvial environment can result in age overestimations, especially for relatively young samples. Methods used for the detection of incomplete resetting, or poor bleaching, are reviewed. It is argued that technique s measuring the OSL signal from small subsamples (aliquots) are most promising for detecting poor bleaching and for obtaining the true age for a sample in which not all grains had their OSL signal completely removed at deposition. Quartz should be the mineral of choice, because it has been shown to yield the most reliable results and because its OSL signal is more rapidly reset than that of feldspar. Aliquot size should be small, with aliquots ideally consisting of a single grain of quartz for samples in which the majority of grains are poorly bleached. Using single-aliquot dating of coarse-grain quartz, age offsets between zero and a few thousand years have been found for modern fluvial deposits. The validity of single-aliquot quartz OSL dating has been demonstrated by application to known-age samples, but for the older age range (>˜13 ka) further proof of the accuracy of the method is essential. The application of quartz OSL dating to investigations of fluvial deposits opens a new realm of possibilities to be explored, as is highlighted by some examples of geological applications.

Optically stimulated luminescence dating of fluvial deposits: a review

Methods of neutron field spectrometry, other than those depending on the use of pulsed neutron sources, are surveyed. Neutron spectrometers are compared with particular reference to characteristics such as energy resolution, useful energy range, neutron detection efficiency and response functions.

Neutron spectrometry-historical review and present status

This report is the first in a series of reports replacing Publications 30 and 68 to provide revised dose coefficients for occupational intakes of radionuclides by inhalation and ingestion. The revised dose coefficients have been calculated using the Human Alimentary Tract Model (Publication 100) and a revision of the Human Respiratory Tract Model (Publication 66) that takes account of more recent data. In addition, information is provided on absorption into blood following inhalation and ingestion of different chemical forms of elements and their radioisotopes. In selected cases, it is judged that the data are sufficient to make material-specific recommendations. Revisions have been made to many of the models that describe the systemic biokinetics of radionuclides absorbed into blood, making them more physiologically realistic representations of uptake and retention in organs and tissues, and excretion. The reports in this series provide data for the interpretation of bioassay measurements as well as dose coefficients, replacing Publications 54 and 78. In assessing bioassay data such as measurements of whole-body or organ content, or urinary excretion, assumptions have to be made about the exposure scenario, including the pattern and mode of radionuclide intake, physical and chemical characteristics of the material involved, and the elapsed time between the exposure(s) and measurement. This report provides some guidance on monitoring programmes and data interpretation.

https://journals.sagepub.com/doi/pdf/10.1177/0146645315577539

ICRP Publication 130: Occupational Intakes of Radionuclides: Part 1.

Advantages and disadvantages of luminescence dosimetry

The catalogue of dosemeters and dosimetric services within the European Union (EU) Member States and Switzerland that was issued by EURADOS in the year 2000 has been updated and extended with information on dosimetric services in the new EU Member States and Bulgaria, Croatia, Romania, Serbia and Montenegro, and Ukraine. The total number of dosimetric services in these European countries is now estimated to be about 200. The present catalogue is based on information collected from 90 European dosimetric services, among which 34 questionnaires from 32 services were obtained over the years 2001-2004 for the first time. This article assesses and updates the present use of personal dosemeters and the extent to which occupationally exposed persons in Europe are monitored with dosemeters able to measure the operational quantity-personal dose equivalent, H P (d). The perspective of joining EU by the new countries accelerated the implementation of the EU Basic Safety Standard Directive to their national regulations. As a result, all newly investigated services reported their ability to measure H P (d). The catalogue provides information on the dosemeters, dose calculation and background subtraction algorithms, calibration methods, energy and angular response, and performance.

/pdf/a-catalogue-of-dosemeters-and-dosimetric-services-within-x6gwjwfhxo.pdf

A catalogue of dosemeters and dosimetric services within Europe--an update.

Among the activities of EURADOS Working Group 2 formed by experts from several European countries is the harmonisation of individual monitoring as part of radiation protection of occupationally exposed persons. Here, we provide information about thermoluminescent detectors (TLDs) applied by the European dosimetric services and the dosimetric characteristics of dosemeters in which these detectors are applied. Among 91 services from 29 countries which responded to the EURADOS questionnaire, 61 apply dosemeters with TLDs for the determination of personal dose equivalent H(p)(10) for photons and beta radiation, and 16 services use TLDs for neutron albedo dosemeters. Those most frequently used are standard lithium fluoride TLDs (mainly TLD-100, TLD-700, Polish MTS-N and MTS-7, Russian DTG-4), high-sensitive lithium fluoride (GR-200, MCP-N) and lithium borate TLDs. Some services use calcium sulphate and calcium fluoride detectors. For neutron dosimetry, most services apply pairs of LiF:Mg,Ti TLDs with (6)Li and (7)Li. The characteristics (energy response) of individual dosemeters are mainly related to the energy response of the detectors and filters applied. The construction of filters in dosemeters applied for measurements of H(p)(10) and their energy response are also reviewed.

/pdf/thermoluminescent-detectors-applied-in-individual-monitoring-382sqaaooo.pdf

Thermoluminescent detectors applied in individual monitoring of radiation workers in Europe--a review based on the EURADOS questionnaire.

The European Radiation Dosimetry Group, EURADOS, established a working group consisting of experts whose aim is to assist in the process of harmonisation of individual monitoring as part of the protection of occupationally exposed workers. A catalogue of facilities and internal dosimetric techniques related to individual monitoring in Europe has been completed as a result of this EURADOS study. A questionnaire was sent in 2002 to services requesting information on various topics including type of exposures, techniques used for direct and indirect measurements including calibration and sensitivity data and the methods employed for the assessment of internal doses. Information relating to Quality Control procedures for direct and indirect measurements, Quality Assurance Programmes in the facilities and legal requirements for "approved dosimetric services" were also considered. A total of 71 completed questionnaires were returned by internal dosimetry facilities in 26 countries. This results in an overview of the actual status of the processes used in internal exposure estimation in Europe. In many ways harmonisation is a reality in internal dose assessments, especially when taking into account the measurements of the activity retained or excreted from the body. However, a future study detailing the estimation of minimum detectable activity in the laboratories is highly recommended. Points to focus on in future harmonisation activities are as follows: the process of calculation of doses from measured activity, establishment of guidelines, similar dosimetric tools and application of the same ICRP recommendations. This would lead to a better and more harmonised approach to the estimation of internal exposures in all European facilities.

/pdf/individual-monitoring-for-internal-exposure-in-europe-and-mtar2pti63.pdf

Individual monitoring for internal exposure in Europe and the integration of dosimetric data.

The current situation amongst Member States is that there are widely differing national requirements for dosimetric services and for dosemeter performance. It is clear that with the free movement of workers within the European Union (EU) and the requirements for individual dosimetry given in Council Directive 96/29 EURATOM, a degree of harmonisation of requirements and procedures of EU Member States would be desirable. A EURADOS action group, made up of members from each of the EU Member States plus Switzerland, was set up with the overall objectives of consolidating within the EU the quality of individual monitoring using personal dosemeters and assisting movement towards harmonised procedures. An outline of the work of the action group is given and the term harmonisation' is discussed.

Harmonisation and dosimetric quality assurance in individual monitoring for external radiation

Measurements have been made with different active dosimetric systems in four Swiss nuclear power plants (2 BWR and 2 PWR) to characterise the mixed n-γ fields. They were performed in 22 positions covering a wide variety of situations inside the containments, in a fuel storage facility and around spent fuel transport flasks. The spectrometric and dosimetric results are presented, discussed and compared. A classification of the neutron spectra in four categories according to their hardness is proposed. The spectra inside the containments are rather soft; they are much harder in the fuel storage facilities and around spent fuel transport flasks. Neutron dose equivalent rates in free access areas are low compared to those due to gammas, whereas in some limited access areas the neutron contribution to the dose equivalent may be appreciable

C. Wernli

Papers

A catalogue of dosemeters and dosimetric services within Europe--an update.

Thermoluminescent detectors applied in individual monitoring of radiation workers in Europe--a review based on the EURADOS questionnaire.

Individual monitoring for internal exposure in Europe and the integration of dosimetric data.

Harmonisation and dosimetric quality assurance in individual monitoring for external radiation

Characterisation of the Mixed Neutron-Gamma Fields Inside the Swiss Nuclear Power Plants by Different Active Systems