Support for the "Vancouver call for action to strengthen expertise in radiological protection worldwide": the position of organisations in formal relations with the International Commission on Radiological Protection (ICRP).

The International Commission on Radiological Protection (ICRP), recently expressed concern that "a shortage of investment in training, education, research, and infrastructure seen in many sectors and countries may compromise society's ability to properly manage radiation risks" and in 2022 announced the "Vancouver call for action to strengthen expertise in radiological protection worldwide". As representatives of organisations in formal relations with ICRP, we decided to promote this position paper to declare and emphasise that strengthening the expertise in radiological protection is a collective priority for all of us.

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.

ICRP workshop on the review and revision of the system of radiological protection: a focus on research priorities-feedback from the international community.

In September 2022, the International Commission on Radiological Protection (ICRP) organised a workshop in Estoril, Portugal, on the 'Review and Revision of the System of Radiological Protection: A Focus on Research Priorities'. The workshop, which was a side event of the European Radiation Protection Week, offered an opportunity to comment on a recent paper published by ICRP on areas of research to support the System of Radiological Protection. Altogether, about 150 individuals participated in the workshop. After the workshop, 16 of the 30 organisations in formal relations with ICRP provided written feedback. All participants and organisations followed ICRP's view that further research in various areas will offer additional support in improving the System in the short, medium, and long term. In general, it was emphasised that any research should be outcome-focused in that it should improve protection of people or the environment. Many research topics mentioned by the participants were in line with those already identified by ICRP in the paper noted above. In addition, further ideas were expressed such as, for example, that lessons learned during the COVID-19 pandemic with regards to the non-radiological social, economic and environment impacts, should be analysed for their usefulness to enhance radiological protection, and that current protection strategies and application of current radiological protection principles may need to be adapted to military scenarios like those observed recently during the military conflict in the Ukraine or the detonation of a nuclear weapon. On a broader perspective, it was discussed how radiation research and radiological protection can contribute towards the Sustainable Development Goals announced by the United Nations in 2015. This paper summarises the views expressed during the workshop and the major take home messages identified by ICRP.

APPLICABILITY OF A COMMERCIALLY AVAILABLE ACTIVE EXTREMITY DOSE-RATE METER TO EYE LENS DOSE MONITORING.

A commercially available active extremity dosemeter is a promising candidate for medical staff aid individual monitoring of the eye lens. We investigated the applicability of the newly developed active extremity dosemeter, which uses a low-energy photon probe, to eye lens dose monitoring by performing a complete characterization of the dosemeters. Performance tests revealed that the active extremity dosemeter would overestimate personal dose equivalent, Hp(3), when the probe is worn close to the lens of the eye of a medial worker without any improvement in the response. Introducing an appropriate filter into the probe for low-energy photon has proven to improve the response. The dosemeter then satisfies the criteria of the personal dosemeter for eye lens dosimetry and can be applicable to individual monitoring of eye lens dose. This article also discusses the applicability of the dosemeter to area monitoring for decision making regarding additional monitoring of the eye lens and the extremities.

DETERMINING THE DOSE RATE DEPENDENCE OF DIFFERENT ACTIVE PERSONAL DOSEMETERS IN STANDARDIZED PULSED AND CONTINUOUS RADIATION FIELDS.

In 2016, the EURADOS working group 12 started a project to gather reliable data concerning the behavior of active personal dosemeters (APDs) used by European hospitals in standardized pulsed and hospital fields. This paper concentrates on the tests that deal with the dose rate dependence of APDs in laboratory tests. The dependence on the dose rate was determined for 10 dosemeter types with continuous radiation of a 60Co source and pulsed radiation of the reference radiation facility of Physikalisch-Technische Bundesanstalt. Furthermore, irradiations were done with continuous radiation of a 137Cs source of the Karlsruher Institute of Technology and with continuous X-rays of the two radiation qualites in radiation beams emerging from the X-ray source assembly, RQR5 and RQR8, of Nofer Institute of Occupational Medicine. For the first time, APDs have been systematically investigated under laboratory conditions in a pulsed reference fields according to ISO/TS 18090-1 and the experience gained by these test procedures will be included in the new IEC/TS 63050.

CONVERSION COEFFICIENTS FROM AIR KERMA TO DIRECTIONAL DOSE EQUIVALENT H'(0.07) FOR PHOTONS.

New conversion coefficients from air kerma free-in-air, Ka, to directional dose equivalent at 0.07mm depth, H'(0.07), are provided for monoenergetic values and for the spectra of the radiation qualities defined in ISO 4037-1. The interpolation procedure of the monoenergetic conversion coefficients from ICRU Report 57 was improved compared to former publications. The values resulting from the new interpolation procedure describe the energy dependence of the conversion coefficients more accurately and differ by up to 5% between 50keV and 100keV from former values. Due to an additional change of the extrapolation to low energies, the values for angles of radiation incidence above 60° and energies below 40keV changed by up to 50%. The influence on the spectrum weighted conversion coefficients is similar to the changes of the monoenergetic values.

INFLUENCE OF NEW MASS ENERGY-ABSORPTION COEFFICIENTS FROM ICRU REPORT NO. 90 ON AIR KERMA TO DOSE EQUIVALENT CONVERSION COEFFICIENTS.

In Report No. 90 of the International Commission on Radiation Units and Measurements (ICRU), new mass energy-absorption coefficients are listed which are based on renormalized Scofield photoeffect cross-sections. The mass energy-absorption coefficients are the basis for the conversion coefficients from air kerma to the operational quantities listed in ISO 4037-3. Although ICRU does not give a recommendation if these new mass energy-absorption coefficients should be applied instead of the values used so far, an examination of the possible consequences for radiation protection quantities is necessary. We calculated the conversion coefficients for the X-ray qualities specified in ISO 4037-1 with the new mass energy-absorption coefficients and with the mass energy-absorption coefficients used so far to determine the deviations. Our calculations show that the change of the conversion coefficients due to the new values from ICRU Report No. 90 is negligible.

TESTING DIFFERENT AREA DOSEMETERS CONCERNING THEIR BEHAVIOUR IN PULSED RADIATION FIELDS.

In Germany, authorised experts are required to measure around an X-ray facility to determine supervised and controlled areas within the scope of a legal regulatory procedure. For this purpose, they have to use area dosemeters which are nationally type-approved by the PTB according to the German measurement and verification act. To date, all available type-approved area dosemeters are only tested in continuous radiation fields, and therefore the technical data of the measuring instruments are valid only for continuous radiation. In practice, however, the majority of facilities use pulsed radiation X-rays. Since no other measuring equipment is available, the authorised experts use supposedly unsuitable dosemeters. But is this really so? In the scope of this article, instruments typically used for these measurements were tested to investigate their behaviour in pulsed radiation fields. The approach is similar to that of Friedrich et al.

Dose measurements in pulsed radiation fields with commercially available measuring components.

Dose measurements in pulsed radiation fields with dosemeters using the counting technique are known to be inappropriate. Therefore, there is a demand for a portable device able to measure the dose in pulsed radiation fields. As a detector, ionisation chambers seem to be a good alternative. In particular, using a secondary standard ionisation chamber in combination with a reliable charge-measuring system would be a good solution. The Physikalisch-Technische Bundesanstalt (PTB) uses secondary standard ionisation chambers in combination with PTB-made measuring electronics for dose measurements at its reference fields. However, for general use, this equipment is too complex. For measurements on-site, a mobile special electronic system [Hupe, O. and Ankerhold, U. Determination of ambient and personal dose equivalent for personnel and cargo security screening. Radiat. Prot. Dosim. 121: (4), 429-437 (2006)] has been used successfully. Still, for general use, there is a need for a much simpler but a just as good solution. A measuring instrument with very good energy dependence for H*(10) is the secondary standard ionisation chamber HS01. An easy-to-use and commercially available electrometer for measuring the generated charges is the UNIDOS by PTW Freiburg. Depending on the expected dose values, the ionisation chamber used can be selected. In addition, measurements have been performed by using commercially available area dosemeters, e.g. the Mini SmartION 2120S by Thermo Scientific, using an ionisation chamber and the Szintomat 6134 A/H by Automess, using a scintillation detector.

X-ray security scanners for personnel and vehicle control: dose quantities and dose values.

After the security related occurrences in the past few years, there is an increasing need for airport security and border controls. In the combat against terror and smuggling, X-rays are used for the screening of persons and vehicles. The exposure of humans to ionising radiation raises the question of justification. To solve this question, reliable and traceable dose values are needed. A research project of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety was initiated. Its task is to measure the ambient dose equivalent, H*(10), and the personal dose equivalent, H(p)(10), for typical types of personnel and vehicle X-ray scanners, using the transmission and/or backscatter method. In the following, the measuring quantities which are to be used for these investigations will be discussed and the measuring instruments will be presented. Furthermore, the experimental set-up is described. For the personnel X-ray scanners investigated, the obtained dose values are in the range from 0.07 to 6 microSv. These values will be compared to the dose values of the natural environmental radiation and some exposures in the field of medicine.

A novel method of radiochromic film dosimetry using a color scanner.

A procedure that allows the improved extraction of the dose information based on the multicolor scanning of the radiochromic film is presented. The basic principle is the determination of the dose values from each color channel of the digital film image in RGB format by applying a nonlinear calibration function. The best estimate of the dose is then a weighted mean of the dose values derived from each color channel. The weighting factors are determined in such a way that the noise in the two-dimensional dose profile is at the minimum. The calculation of the weighting factors is presented; they are chosen to be proportional to the signal-to-noise ratio, Si/v(i)2, in all three color channels, i=red, green, or blue. The data reduction can be fully computerized, including the "cleaning" of the digital image from dust and scratches. It is highly reproducible, which is important for quality assurance, and easy to use. Our novel evaluation procedure combines the good response in the low dose range of the red color with the extended dose range of the blue and green color channels (response up to 10,000 Gy), making use of one single, steady evaluation function. Therefore, a smooth evaluation is possible in a wide dose range. For the interpretation of measurements with the radiochromic films the spatial inhomogeneity of the film's response to ionizing radiation is very important. Investigations on both film types, HS and MD55-2, as well as on the new EBT film have been carried out.