EURADOS project on the impact of the proposed ICRU operational dose quantities.

Following the publication of the joint The International Commissions on Radiation Units and Measurements (ICRU) and on Radiological Protection (ICRP) report on new operational quantities for radiation protection, the European Dosimetry Group (EURADOS) have carried out an initial evaluation. The EURADOS report analyses the impact that the new quantities will have on: radiation protection practice; calibration and reference fields; European and national regulation; international standards and, especially, dosemeter and instrument design. The task group included experienced scientists drawn from across the various EURADOS working groups.

The EURADOS CR-39 Quality task for the optimisation and harmonisation of personal neutron dosimetry with CR-39 (PADC).

CR-39 (PADC) nuclear track detectors are among the most widespread devices used for personal neutron dosimetry; however, some issues related to the variable material quality of the CR-39 polymer hinder the performance of CR-39-based dosemeters. For this reason, the Working Group 2 (WG2) of the European Radiation Dosimetry Group (EURADOS) has recently launched the CR-39 Quality task, a project aimed at improving and harmonising personal neutron dosimetry with CR-39 in Europe. Whitin this task, a close collaboration among researchers, individual monitoring services and dosemeter grade CR-39 manufacturers is achieved, thus facilitating the direct dialog between producer and consumer to reach an optimised material for personal neutron dosimetry applications.

EURADOS STRATEGIC RESEARCH AGENDA 2020: VISION FOR THE DOSIMETRY OF IONISING RADIATION.

Since 2012, the European Radiation Dosimetry Group (EURADOS) has developed its Strategic Research Agenda (SRA), which contributes to the identification of future research needs in radiation dosimetry in Europe. Continued scientific developments in this field necessitate regular updates and, consequently, this paper summarises the latest revision of the SRA, with input regarding the state of the art and vision for the future contributed by EURADOS Working Groups and through a stakeholder workshop. Five visions define key issues in dosimetry research that are considered important over at least the next decade.

EURADOS education and training activities.

This paper provides a summary of the Education and Training (E&T) activities that have been developed and organised by the European Radiation Dosimetry Group (EURADOS) in recent years and in the case of Training Courses over the last decade. These E&T actions include short duration Training Courses on well-established topics organised within the activity of EURADOS Working Groups (WGs), or one-day events integrated in the EURADOS Annual Meeting (workshops, winter schools, the intercomparison participants' sessions and the learning network, among others). Moreover, EURADOS has recently established a Young Scientist Grant and a Young Scientist Award.

The work programme of EURADOS on internal and external dosimetry.

Since the early 1980s, the European Radiation Dosimetry Group (EURADOS) has been maintaining a network of institutions interested in the dosimetry of ionising radiation. As of 2017, this network includes more than 70 institutions (research centres, dosimetry services, university institutes, etc.), and the EURADOS database lists more than 500 scientists who contribute to the EURADOS mission, which is to promote research and technical development in dosimetry and its implementation into practice, and to contribute to harmonisation of dosimetry in Europe and its conformance with international practices.

DOSIMETRIC QUALITY ASSURANCE INTERPRETED FOR ISO 17025 IN PUBLIC HEALTH ENGLAND'S PERSONAL DOSIMETRY SERVICE.

Many individual monitoring services (IMSs) have long experience in delivering high-quality dosimetry, and many follow rigorous quality assurance (QA) procedures. Typically, these procedures have been developed through experience and are highly effective in maintaining high-quality dose measurements. However, it is not always clear how the range of QA procedures normally followed by IMSs maps on to the various requirements of ISO 17025.

USE OF A SIMPLE THERMALISED NEUTRON FIELD FOR QUALITY ACCEPTANCE OF WHOLE BODY TLDS.

The individual monitoring service of Public Health England (PHE) uses Harshaw™ whole-body and extremity thermoluminescent dosemeters (TLDs) with high-sensitivity lithium fluoride LiF:Mg,Cu,P, together with Harshaw 8800™ automated readers. The neutron-insensitive, (6)Li-depleted variety of TLD material is used by PHE because the service provides separate neutron and photon dosemeters. The neutron dosemeters are not sensitive to photons and vice versa Since insensitivity to neutrons is a supply requirement for TLDs, there is a need to test every new (annual) consignment for this.

The lens of the eye: exposures in the UK medical sector and mechanistic studies of radiation effects.

The recommendation from the International Commission on Radiological Protection that the occupational equivalent dose limit for the lens of the eye should be reduced to 20 mSv year(-1), averaged over 5 years with no year exceeding 50 mSv, has stimulated a discussion on the practicalities of implementation of this revised dose limit, and the most appropriate risk and protection framework to adopt. This brief paper provides an overview of some of the drivers behind the move to a lower recommended dose limit. The issue of implementation in the medical sector in the UK has been addressed through a small-scale survey of doses to the lens of the eye amongst interventional cardiologists and radiologists.

Public Health England survey of eye lens doses in the UK medical sector.

The ICRP has recently recommended that the occupational exposure limit for the lens of the eye be reduced to 20 mSv in a year, averaged over defined periods of 5 years, with no single year exceeding 50 mSv. There has been concern amongst some groups of individuals, particularly interventional cardiologists and radiologists as well as relevant professional bodies, that implementation of these recommendations into UK law will adversely affect working patterns. However, despite a number of informative European studies, there is currently little UK dosimetry data available upon which judgements can effectively be based.

Monte Carlo modelling of 90Sr/90Y and 85Kr beta fields for Hp(3) measurements.

In support of research aimed at developing a thermoluminescence dosemeter capable of accurately measuring ionising radiation doses to the lens of the eye, Monte Carlo modelling of a standard beta exposure set-up has been performed. It was found that electrons with an energy distribution corresponding to the beta emission spectrum from (85)Kr deposit negligible doses at a depth of 3 mm in tissue, but doses from (90)Sr/(90)Y are significant; free in air and fluence-to-Hp(3,θ°) and -Hp(0.07,θ°) conversion coefficient data were found for this field for exposures at 0°, 30° and 60° angles of incidence, and the response characteristics of the new eye dosemeter were evaluated.

Type testing of a head band dosemeter for measuring eye lens dose in terms of H(P)(3).

A new head band dosemeter, for the measurement of eye lens dose in terms of Hp(3), has been type tested by Public Health England's Centre for Radiation, Environmental and Chemical Hazards [formerly part of the UK Health Protection Agency (HPA)]. The type tests were based on the International Standard ISO 12794, drawing also upon earlier work at HPA. The results show that, unlike many existing dosemeters, the new head band dosemeter correctly measures Hp(3) for beta radiations as well as photons.

Radiation-induced cataracts: the Health Protection Agency's response to the ICRP statement on tissue reactions and recommendation on the dose limit for the eye lens.

This paper presents the response of the Health Protection Agency (HPA) to the 2011 statement from the International Commission on Radiological Protection (ICRP) on tissue reactions and recommendation of a reduced dose limit for the lens of the eye. The response takes the form of a brief review of the most recent epidemiological and mechanistic evidence. This is presented together with a discussion of dose limits in the context of the related risk and the current status of eye dosimetry, which is relevant for implementation of the limits.

Long-term stability of Harshaw LiF:Mg,Cu,P TLDS.

The sensitivity of Harshaw™ magnesium/copper/phosphorus-doped lithium fluoride is shown to be stable over long time periods, even when, as is often the case in practical operations, the TLDs are read out only three times a year.

Evaluating the performance of the Harshaw™ DXTRAD LiF:Mg,Cu,P finger ring with two different thickness filters.

Amongst the dosemeters offered by the Health Protection Agency (HPA) Personal Dosimetry Service are finger rings, which use the Harshaw™ DXTRAD element. This paper describes restricted-type testing carried out by HPA on the previously untried combination of the LiF:Mg,Cu,P material and a thicker filter (42 mg cm(-2)). The tests were based on ISO 12794 [International Organization for Standardization.

Practical low dose limits for passive personal dosemeters and the implications for uncertainties close to the limit of detection.

Recent years have seen the increasing use of passive dosemeters that have high sensitivities and, in laboratory conditions, detection limits of <10 µSv. However, in real operational use the detection limits will be markedly higher, because a large fraction of the accrued dose will be due to natural background, and this must be subtracted in order to obtain the desired occupational dose. No matter how well known the natural background is, the measurement uncertainty on doses of a few tens of microsieverts will be large.

Different versions of the right answer: the importance of measurement uncertainty in radiation dosimetry.

The performance of radiation dosemeters that are issued by approved individual monitoring services generally meet international standards, with typical results within a few tens of per cent of the reference value. Experienced dosimetry practitioners will understand the uncertainties and treat monitoring results with due caution. However, where different technologies (for example, where passive and electronic dosemeters) are used side by side, apparent disagreements can arise.

Type testing of a new TLD for the UK Health Protection Agency.

The UK Health Protection Agency is currently commissioning a new personal dosimetry system based on the use of Harshaw two-element thermoluminescent dosemeter cards using LiF:Mg,Cu,P. Results of extensive type testing carried out with reference to IEC 61066, "Thermoluminescence Dosimetry Systems for Personal and Environmental Monitoring", have been presented.

Comparison of time effects, decision limit and residual signal in Harshaw LiF:Mg,Ti and LiF:Mg,Cu,P.

The personal dosimetry service of the UK Health Protection Agency--formerly of the National Radiological Protection Board (NRPB)--is currently commissioning a body thermoluminescence dosemeter (TLD) system based on the use of Harshaw 8800 readers and two-element cards. As part of the process, studies have been carried out into the long-term time dependence of response, the limit of detection and the magnitude of the signal remaining after recommended processing. TLD cards containing both conventional lithium fluoride (LiF:Mg,Ti) and the high-sensitivity material LiF:Mg,Cu,P were available, thus allowing a comparison between the two types of material.

Type testing of an extremity finger stall dosemeter based on Harshaw TLD EXTRAD technology.

A new type of extremity dosemeter, which incorporates the Harshaw TLD EXTRAD dosemeter element into a PVC finger stall, has been developed. The dosemeter uses high-sensitivity lithium fluoride, (7)LiF:Mg,Cu,P (TLD-700H) in a thin 7 mg cm(-2) layer, with alternative coverings of PVC at 10 mg cm(-2) and aluminised polyester at 3.2 mg cm(-2).

Experience of radiation passbooks in the UK NRPB dose record keeping service.

The National Radiological Protection Board (NRPB)--now part of the new UK Health Protection Agency (HPA)--has operated an automated Dose Record Keeping (DRK) Service for over 30 y, and currently maintains records for some 10,000 workers. A proportion of these are designated as Outside Workers, and are issued with Radiation Passbooks, under the Ionising Radiations Regulations 1999 (IRR99). The present study reports the operational experience of NRPB's DRK Service in issuing passbooks, providing advice to users and issuing tailored reports.

Comparison of the effects of exposure to light in Harshaw LiF:Mg,Ti and LiF:Mg,Cu,P.

The response of thermoluminescence dosemeters (TLDs) to light, in various conditions, has been studied. TLD cards containing both conventional lithium fluoride (LiF:Mg,Ti) and the high-sensitivity material LiF:Mg,Cu,P were available, so permitting a comparison between the two types. Also available for the tests were Harshaw extremity EXT-RAD (LiF:Mg,Cu,P) dosemeters.

Extremity TLD high dose response.

The Extremity TLD service provided by the UK National Radiological Protection Board (NRPB) supplies dosemeters to 3200 wearers in various occupations, primarily in the industrial, research and medical sectors. The dosemeters and associated processing equipment were supplied by Bicron/NE Technology Ltd and the service in this form has been operating successfully for over 15 years. The dosemeter uses LiF powder, which is deposited onto the adhesive face of a carbon-loaded Kapton tape.