BIPM

CCRI section I meeting - 2025

2025-12-02T11:11:29Z

The 2025 meeting of Section I “Dosimetry” of the Consultative Committee for Ionizing Radiation took place in Minamisoma City, Fukushima Prefecture, Japan, from 17 to 18 September 2025, with the support of the Fukushima Institute for Research Education and Innovation (F-REI) and the National Metrology Institute of Japan (NMIJ). Around 50 participants, including 10 who joined remotely, gathered over two days to review the status of dosimetry and to consider future developments.

In addition to presentations on completed, ongoing, and planned comparison exercises, the program dedicated significant time to technical discussions on dosimetry in diagnostic radiology, Monte Carlo simulations in dosimetry, and challenges in radiation processing. These exchanges, together with the outcomes of the two previous workshops, were brought forward for revision of the strategy plans of CCRI(I) and the BIPM.

The committee adopted a series of resolutions that reflect both technical and organizational priorities. It endorsed the recommendations from the Brachytherapy Workshop held on September 15 and proposed the establishment of a task group to prepare a protocol for a proton dosimetry comparison to be ideally undertaken within the next two years. A new Working Group was also proposed to accelerate the development of proton primary standards across the RMOs, to investigate the challenges posed by carbon ion dosimetry, and to extend metrology into other emerging treatment modalities. Another task group was proposed to provide guidance on traceability and uncertainty estimation in the use of Monte Carlo radiation transport systems applied to dosimetry standards. It was suggested that the KCWG(I) would benefit from new members and an updated terms of reference, while the committee also resolved to appoint a new representative to the CCRI RTQI Working Group.

Requests were made to other subcommittees in support of these goals. The CCRI COM WG was asked to explore ways of enhancing the visibility and impact of reports submitted by delegates and liaisons, without compromising the depth of information currently provided. The KCWG(I) was invited to consider the treatment of CMCs that exceed the 15-year comparison period under extraordinary circumstances beyond a laboratory’s control, and to review existing physical and normative standards to determine whether current Key Comparisons can accommodate additional beam qualities, such as the ISO4037 N-series for radiation protection.

With respect to the BIPM strategy, the CCRI(I) concluded that there is no pressing need at for the BIPM to develop a high-energy electron standard but has a role to play in defining the KCRV for a future comparison. It emphasized, however, the critical importance of maintaining a therapy-level Co-60 source at the BIPM to support both comparisons and calibrations.

Finally, the committee welcomed two new members, OAP (Thailand) and FANR (UAE), whose presentations further underlined the vitality, diversity, and richness of the CCRI(I) community.

Medical Applications of Radiation and Metrology Standards Workshop – 16 September 2025

2025-12-02T11:10:22Z

A half-day Workshop on Medical Applications of Radiation and Metrology Standards Workshop was held at Minamisoma city, Fukushima prefecture, Japan, 16 September 2025. It was organized by the Fukushima Institute for Research Education and Innovation (F-REI) with the support of National Metrology Institute of Japan (NMIJ) and the CCRI section I “dosimetry” and was followed by 116 participants, 48 of them connected remotely.

Japan has a long history of ionizing radiation therapy, and as expected for a technologically advanced nation, boasts a very impressive range of radiotherapy facilities. Japan is a recognized world leader in innovative treatment modalities, including carbon-ion therapy, theranostics (use of radionuclides for diagnosis and treatment of cancer) and boron neutron capture therapy (BNCT). The Fukushima district is also in an era of major revitalization, with the Fukushima Institute for Research Education and Innovation having an ambitious plan to become a major research and development institute, centered around 5 technology pillars, which all directly or indirectly implicate ionizing radiation measurement science. The workshop opened with a detailed overview of F-REI and its combined technological and societal aims. This was followed by presentations on developments in radiological medicine and the status of radiotherapy in Japan. In the second part of the workshop, the focus narrowed to ionizing radiation (IR) metrology with contributions from CCRI members and from the Japanese National Metrological Institute (NMIJ) and long-time partner of the international IR community.

During the discussions that followed, it was noted that information sharing, as through this workshop, between entities such as F-REI, NMIJ and CCRI is of mutual benefit and necessary to explore future collaborations and develop common messaging on the benefits of ionizing radiation in addressing global health needs. Best practice in engaging with local communities, high schools and universities on the challenges and opportunities of radiation science was also shared.

CCRI also deeply expressed its gratitude to F-REI and NMIJ for their exceptional support and welcome in all the events organized at Minamisoma that week.

Metrology for Proton and Hadron Therapy Workshop – 16 September 2025

2025-10-28T07:51:19Z

A half-day Workshop on Metrology for Proton and Hadron Therapy Workshop was held at Minamisoma city, Fukushima prefecture, Japan, 16 September 2025. It was organized by the section I “dosimetry” of the Consultative Committee for Ionizing Radiation with the support of the Fukushima Institute for Research Education and Innovation (F-REI) and the National Metrology Institute of Japan (NMIJ). About 60 participants, 20 of them connected remotely, discussed the status and future developments in metrology for therapeutic applications of protons and light ions*.

Japan has a long history of proton/hadron therapy, and therefore the workshop opened with an overview of this modality over the last 40 years. Following this, attendees heard technical presentations on the state-of-the-art in metrology and descriptions of new activities related to reference dosimetry protocol development. Prior to a discussion on standards and comparisons, the theme returned to the clinical perspective to provide a clear statement of stakeholder needs in dosimetry.

A primary outcome from the discussions was that there is a need to initiate a comparison between NMIs/DIs having proton primary standards already established, as well as a desire for guidelines and support for the members of CCRI(I) that do not currently have such a capacity but have a future requirement to meet the dosimetry needs of national proton therapy programs.

This “workshop” was followed by a meeting of the Section I “dosimetry” of the Consultative Committee for Ionizing Radiation, where these needs were discussed and led to the proposal of a creation of a CCRI(I) task group to rapidly create a comparison program in proton therapy, and a working group focused on the development of metrology for emerging therapy modalities.

* the term “light ions” refers to ions with atomic number in the range 2-8

Brachytherapy Standards Workshop – 15 September 2025

2025-10-28T07:50:38Z

A special meeting, run as a 1-day Workshop, of the Brachytherapy Standards Working Group (BSWG) of the section I “dosimetry” of the Consultative Committee for Ionizing Radiation - CCRI(I), was held at Minamisoma city, Fukushima prefecture, Japan, 15 September 2025 with the support of F-REI and NMIJ. 46 participants, 7 of them connected remotely, discussed the status and future developments in metrology for brachytherapy dosimetry.

This “workshop” started with 3 presentations providing an overview of brachytherapy in clinical practice and was followed by 3 technical reviews of the physical standards in brachytherapy dosimetry (High Dose Rate, Low Dose Rate, Electronic Brachytherapy). 13 NMIs and DIs then presented their current activities to provide a global picture of brachytherapy standards and dissemination. The final session of the workshop was a discussion on the needs for new comparisons, options for maintaining the current BIPM.RI(I)-K8 comparison for HDR Ir-192 air kerma, and how CCRI(I) and BIPM should address future developments and emerging needs.

A clear outcome from the discussions was that the BIPM.RI(I)-K8 based on bi-lateral comparisons between NMIs/DIs and the BIPM should continue in its current form with the strong recommendation of the addition of a second BIPM well chamber to provide improved robustness, and a third one as a preferred option.

The workshop attendees also supported the relaunch of the BSWG(I) with a new term of reference, a new chair appointment and the support from BIPM IR staff. To reflect all the expressed needs during the meeting, the terms of reference should include the expansion of brachytherapy comparisons to LDR I-125, the exploration of the value of adopting a D _w formalism in brachytherapy dosimetry protocols (to be consistent with external beam dosimetry), a survey of electronic brachytherapy, the definition of CCRI recommendations on source model correction factors and the development of international guidelines (CCRI/IAEA) on the values to be entered into HDR brachytherapy treatment units (afterloaders). In regard to this final point, it was clearly stated that measured, rather than manufacturer-provided, values should be used.

This “workshop” was followed by a meeting of the CCRI(I), where these recommendations were discussed and approved.

nHBEAM 2025 - IAEA-CCRI(III) workshop on Neutron Beams at High Energy: Applications and Metrology

2025-09-16T12:20:52Z

A joint CCRI-IAEA workshop was held at the IAEA Headquarters in Vienna, Austria, from 7 to 8 July 2025. The focus of the meeting was to discuss the needs of high energy neutrons in various applications and how neutron metrology can address them, with the particular focus of finding available and suitable facilities in the world. The workshop attracted 119 participants (33 remotely) having interests in different fields related to high energy neutrons, who came together for 2 days filled with high level scientific presentations and extensive discussions. The topics of the presentations covered all fields in which high energy neutrons play an important role: space and aviation applications, radiobiology, high energy accelerator facilities, fast and high energy neutron facilities, metrology, reference standards, dosimetry, and instrumentation.

During the first day of the meeting, 18 presentations were given demonstrating the needs and challenges related to high energy neutrons. The second day was dedicated to more general overview talks, focused on facilities for the production of monoenergetic and broad neutron fields, on instrumentation and on nuclear data.

A clear result from the presentations and discussions was the worldwide need for standards for high energy neutrons and better access to well characterized facilities being able to produce quasi-monoenergetic and broad energy range neutron fields.

A report summarizing the conclusions is under preparation and will be published soon. The workshop was followed by a meeting of the Working Group 11 “high energy radiation fields” of EURADOS and the 2025 meeting of the Section III “neutron measurements” of the Consultative Committee for Ionizing Radiation. Both committees continued the discussions started during the workshop with special emphasis on their specific needs.

CCRI Section III meeting - 2025

2025-08-11T13:57:15Z

The 2025 meeting of section III “neutron measurements” of the Consultative Committee for Ionizing Radiation was held at the head quarter of the International Atomic Energy Agency (IAEA), Vienna, Austria, from 9 to 11 July 2025 under the chair of Andreas Zimbal, PTB, Germany. About 40 participants, 7 of them connected remotely, discussed for 3 days the actual status and future developments in neutron metrology.

In addition to the discussions about finished, ongoing and planned comparison exercises, a huge topic was the further strategy of CCRI(III) concerning metrology of high energy neutrons with energies about 20 MeV. CCRI(III) decided to create a task group with the goal to prepare and organize a possible key comparison for high energy neutrons in the next two years.

A further topic was the discussion about the needs for neutron metrology in the growing field of Boron Neutron Capture Therapy (BNCT), which resulted in the proposal to organize a dedicated workshop in 2026, possible organized by NMIJ, to get a more profound overview of activities and scientific challenges related to this medical application of neutron radiation.

In addition to the presentations of the members of CCRI(III) about their progress and developments since the last meeting, four guest institutes presented their new engagement in neutron metrology, showing the worldwide growing demand in this fields. All four institutes were encouraged by the CCRI(III) to continue their activities and were invited to participate again as guests at the next meeting, which is planned to be held in 2027.

Dr Haoran Liu receives the Best Poster Award at ICRM 2025

2025-06-12T08:32:47Z

See the poster

Dr Haoran Liu from the National Institute of Metrology (China) was awarded one of the two Best Poster Awards at the 24th International Conference on Radionuclide Metrology and its Applications (ICRM 2025), held in Paris, France, from May 19 to 23, 2025.

Dr Liu's award-winning poster, "A Novel Digital Background Correction Algorithm for the Selective Sampling Method," offers a fresh perspective on nuclear counting techniques. The study introduces an innovative digital background correction algorithm for the Selective Sampling (SESAM) method, which was originally introduced by Jörg W. Müller from the Bureau International des Poids et Mesures (BIPM) in the 1980s as an alternative to conventional β-γ coincidence counting. The Müller algorithm for background correction tended to have problems when sample count rates were not significantly higher than the background. To overcome this, Dr. Liu and his colleagues developed a novel digital cross-selective sampling background correction algorithm that operates on list-mode digital data offline and introduces innovative, virtually-created cross-selective sampling modes not feasible with conventional correction methods. These additions significantly enhance the precision and reliability of the background correction process, demonstrating that the new digital SESAM counting method enhances accuracy, especially for samples with moderate activity levels, and solidifies SESAM as a dependable alternative to traditional β-γ coincidence counting.

The basis for the award, as stated by the jury, is that the “subject of the poster is highly relevant to the field of radionuclide metrology, revisiting an old but fundamental method. The poster is well-structured with an appealing layout, includes all relevant information, and presents a novel approach with clear explanations. The presenting author was frequently present at the poster, consistently willing to engage in discussion and provide additional information."

BIPM Extends Use of Off-Site Facility to Calibrate Secondary Standards for Radiation Protection Dosimetry

2024-11-25T12:36:52Z

The BIPM is advancing dosimetry services for National Metrology Institutes (NMIs) by expanding its use of off-site facilities for calibration and comparison services.

Responding to the needs of the metrology community, as of September 2024, the Bureau International des Poids et Mesures (BIPM) is once again offering a calibration service (in addition to a comparison service) for radiation protection at the International Atomic Energy Agency (IAEA) ¹³⁷Cs irradiation facility in Austria.

This re-established calibration service of secondary standards assures the traceability to the SI units for the radiation protection level.

Who will benefit from this?

This service is being offered to NMIs and Designated Institutes (DIs) from Member States that maintain secondary standards. However, as this also includes the IAEA, its network of Secondary Standards Dosimetry Laboratories (SSDL) will also benefit.

These calibrations play a crucial role in ensuring the reliability of dosimeters and radiation protection devices used in vital sectors like nuclear safety, healthcare and environmental monitoring.

By re-establishing this service, the BIPM underscores its commitment to supporting global dosimetry and contributing to the international metrology community’s efforts to establish the traceability to international reference standards for radiation protection levels.

Background

The BIPM started to use the IAEA’s ¹³⁷Cs facility in 2023, re-establishing the key comparison BIPM.RI(I)-K5. The key comparison reference value (KCRV) is determined using a BIPM primary standard for high-precision measurements, along with a dedicated measuring system, ensuring rigorous technical accuracy. Through this initiative, NMIs holding primary standards can continue to participate in this ongoing key comparison, updating their degrees of equivalence and further validating their capabilities in disseminating the unit of measurement critical for radiation protection.

Successful comparisons have been carried out in 2023 with the Bundesamt für Eich- und Vermessungswesen (BEV), Austria and the Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Spain, and can be found in the BIPM Key Comparison Database (KCDB). Comparisons with the Laboratoire National Henri Becquerel (LNE-LNHB) and the Główny Urząd Miar (GUM), made in 2024, are in the process of being approved.

Workshop on Current and Future Applications of Mass Spectrometry in Radionuclide Metrology, May 16, NPL

2025-12-03T08:54:00Z

The CCRI(II) Mass Spectrometry Task Group hosted a hybrid working group meeting on “The Current and Future Applications of Mass Spectrometry in Radionuclide Metrology” (47 on-site, 108 online from approximately 50 countries). This was a follow-up to the online workshop and survey organized by the Task Group, where regular workshops were highlighted as a topic of interest. This two-day event was combined with the final stakeholder workshop of the Euramet MetroPOEM project, which focused on the application of mass spectrometry for measurement of stable and radioactive pollutants at environmental levels, through the provision of new methods, good practice guides, traceable standards, and reference materials.

The workshop included talks and posters from University of Vienna, University of Mainz, AWE, GAU Radioanalytical, SUERC, Lawrence Livermore, University of Manchester, DTU, NPL, NIST, as well as the MetroPOEM consortium. In line with previous work by the Task Group, the provision of standards and reference materials to support the increasing use of mass spectrometry was a priority, as was the ongoing development of instrumentation to further expand radionuclide measurement.

Use of Mass Spectrometry in Radioactivity Measurements / Workshop at NPL on 16 May 2025

2024-10-10T15:39:18Z

Recently, the CCRI(II) Task Group on the use of mass spectrometry in radionuclide metrology distributed a survey to more than 250 NMIs, DIs, and relevant stakeholders to determine current and planned activities in the use of mass spectrometry for radionuclide measurements. There was a 20 % response rate from laboratories of all Regional Metrology Organizations (SIM, EURAMET, AFRIMETS, GULFMET, COOMET, and APMP), giving a wide breadth of activities and perspectives. Results on the number and designs/techniques of various mass spectrometry instrumentation in use, current application areas, and future projects (including chronometry and medical isotopes) were obtained. Specific challenges to metrological advances were recognized such as a lack of appropriate reference materials (and a need for calibration and quality control materials).

The results are available in the dedicated report

Participants were also asked about future activities they would like to see the task group take on; the vast majority (92 %) would like to have a workshop or similar information-sharing opportunity focused on radionuclide measurement by mass spectrometry, especially concerning certified reference materials, traceability, databases, and methods development. Therefore, the task group will hold the 16 May 2025 (i.e., the Friday before the next ICRM meeting) a follow-up workshop (“Current and Future Applications of Mass Spectrometry in Radionuclide Metrology”) at the NPL, and key takeaways are planned to be presented at that meeting. In addition, the task group is currently preparing a manuscript (“The Role of Mass Spectrometry in Radionuclide Metrology”) to be published later in 2025. A written report of potential metrology activities for distribution to CCRI(II) members will be completed in September 2025, and will be discussed at the biennial CCRI(II) meeting in November 2025 and held at the BIPM.

David Burns retires from the BIPM

2024-09-18T09:46:14Z

Dr David T. Burns, PhD, FInstP, will retire from his position as principal research physicist at the Bureau International des Poids et Mesures (BIPM) on 30 September 2024. After a distinguished career spanning several decades, Dr Burns will leave behind a legacy of excellence and significant contributions to the field of ionizing radiation metrology.

Dr Burns began his academic journey at the University of Glasgow (UK) where he was awarded the Thomson Prize in Experimental Physics. He earned his doctorate in nuclear structure research from the university’s Kelvin Laboratory before joining the National Physical Laboratory (NPL) in the UK. At the NPL, he led the electron dosimetry group and was instrumental in advancing calorimetric measurement standards for absorbed dose at industrial levels.

In 1996, Dr Burns joined the BIPM, where he dedicated his work to the development and refinement of primary measurement standards for air kerma and absorbed dose. His expertise has greatly influenced dosimetric protocols for radiotherapy, including significant contributions to the widely used TRS-398 protocol of the International Atomic Energy Agency (IAEA). Dr Burns is a co-author of the influential book Fundamentals of Ionizing Radiation Dosimetry. His extensive research has resulted in approximately 150 peer-reviewed publications. In 2011, he was elected a Fellow of the Institute of Physics (UK).

Dr Burns served as the BIPM observer at the International Commission on Radiation Units and Measurements (ICRU) annual meetings from 1997 to 2011 and was elected to the Commission in 2012. His leadership within the ICRU’s Fundamental Quantities and Units Committee, where he was appointed chairman in 2014, has been instrumental in maintaining rigour in the use of quantities and units in global radiation measurements. Additionally, since 2014 he has been a key member of the Scientific Committee of the IAEA/WHO Network of Secondary Standards Dosimetry Laboratories (SSDL Network), guiding the Network’s operations and the IAEA’s Dosimetry Programme.

Throughout his career, Dr Burns has been recognized for his profound impact on radiation physics and metrology. His dedication to advancing measurement standards has ensured greater accuracy and reliability in radiation dosimetry world-wide. His contributions have not only enhanced scientific understanding but also improved safety and effectiveness in medical, industrial and environmental applications of ionizing radiation.

As Dr Burns retires, we extend our heartfelt gratitude for his exceptional service and unwavering commitment to the field. His legacy will continue to inspire future generations of metrologists and researchers and will be passed on through his successor Dr Anna Villevalde and his long-standing colleague Dr Cecilia Kessler. We wish him all the best in his retirement and this exciting new chapter of his life.

ESIR measurements to start with Technetium-99

2024-10-24T09:56:18Z

The BIPM is pleased to announce the receipt of the first standard solution of Technetium-99 (Tc-99) from the LNE-LNHB for measurement using the newly implemented Extension of the International Reference System (ESIR). This marks the launch of the BIPM.RI(II)-K5 comparison, with the first of the 14 isotopes selected by the Consultative Committee for Ionizing Radiation (CCRI).

The ESIR was developed and implemented at the BIPM after three years of collaborative effort. It enables the measurement of radionuclides that could not previously have been assessed by the original SIR system, allowing NMIs and Designated Institutes (DIs) to obtain degrees of equivalence for these specific isotopes.

Technetium-99, a long-lived by-product of medical diagnostics, nuclear industry activities, and fallout testing, is a significant concern for the environment. The BIPM and NMIs are proud to contribute to enhancing the metrological traceability of this challenging-to-measure radionuclide.

World Metrology Day 2024

2024-07-23T11:52:15Z

At first sight, the theme for World Metrology Day 2024 – Sustainability – does not seem to have much overlap with the activities of primary and secondary standard dosimetry laboratories. However, when one considers the meaning of sustainability in the light of the 17 UN Sustainability Goals it becomes more obvious that ionizing radiation is very relevant to the subject and, by inference, ionizing radiation metrology has an important role to play in supporting (and sustaining) various applications. Here are just a few examples.

First of all, ionizing radiation metrology contributes to “Ensure healthy lives and promote well-being for all at all ages”. Ionizing radiation is one of mankind's main tools in the fight against cancer, with radiation therapy treatments becoming increasingly varied (both in terms of beams and methods) and tailored to the biological specificities of each individual. The increasing cancer burden, identified by the IAEA more than a decade ago, has driven the increased use of radiation-based diagnostic procedures, and NMIs/DIs have responded by the development of novel systems for the accurate comparison of national standards for radiotherapy, brachytherapy, mammography and other x-ray imaging approaches. There is now strong clinical evidence that proton therapy has significant benefits in treating pediatric cancers and CCRI Section I has initiated discussions around the need for international comparisons of proton dosimetry standards. To exploit all the benefits of proton therapy, the effects of unwanted dose due to secondary high energy neutron radiation needs to be investigated. CCRI Section III has recently convened a task group to investigate how high-energy neutron beams suitable for metrological applications can be produced and how the community can come together to use them in an efficient and sustainable manner. Ultra-high dose rate (FLASH) therapy is attracting significant attention and multiple research groups are investigating the technology required to accurately measure and deliver these almost-instantaneous treatments. Perhaps the most disruptive, and exciting, treatment technique is radiopharmaceutical therapy (RPT), and CCRI Section II has been leading an international effort to develop normative standards for clinical implementation as well as co-ordinate the necessary research into standardizing the various radioisotopes being investigated for RPT, highlighted by a recent workshop on alpha-particle therapy (02/2024).

Ionizing radiations can also help to “Take urgent action to combat climate change and its impact”. Within the context of global commitments to reduce greenhouse gases (GHGs), there is the requirement to accurately measure CO2 and CH4 emissions from different sources. The radioactive signature from C-14 can be used as part of this monitoring system. Other radioisotopes, like Be-7 and Na-22, produced by cosmic radiations in the atmosphere could also be useful tools to better understand key atmospheric processes and help to obtain more accurate prediction of global warming. CCRI(II) has put several of these radioisotopes, and in particular C-14, on the priority list for the upcoming activity comparisons with the new reference system (the extended SIR or ESIR) maintained by the BIPM and has started discussions among various specialists in this field to better match the needs pointed out at the last BIPM-WHO Metrology for climate action workshop (09/2022).

In addition, ionizing radiations contribute to ensuring “Availability and sustainable management of water and sanitation for all”. A range of radiation beams – primarily Co-60 and high-energy electrons – have been used for decades for the sterilization of single-use medical goods. The same techniques can also be applied to food, water and waste treatments to eliminate pathogens and certain chemical contaminants. In the field of high-dose dosimetry, CCRI partners with the ASTM international E61 committee, which is the primary forum worldwide for radiation processing standards.

Ionizing radiation metrology is also deeply involved in “Ensuring access to affordable, reliable, sustainable and modern energy for all”. The decarbonization of energy production will require multiple technologies but at least in the shorter-term, fission-based nuclear power will be crucial for many countries. The safe operation of such nuclear facilities requires accurate radiation protection measurements and the calibration services that NMIs/DIs provide support the delivery of sustainable and affordable energy while assuring minimal environmental impact, e.g., through the measurement of radionuclides in natural matrices. Looking further into the future, small and new generation fission reactors as well as fusion technology have the potential to offer a significant resource for energy production. All will need more accurate nuclear data (nuclear decay, neutron cross-sections, etc.) with several challenges for ionizing radiation metrology. For example, the mechanisms of fusion are sufficiently different from fission that new facilities will be necessary to produce the reference neutron beams needed for metrological support.

“Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation” is also part of the missions of the ionizing radiation metrology. Metrology can indeed be viewed as the quantification of knowledge, and various leaders since the industrial revolution have espoused the value of that quantification. The techniques that NMIs/DIs develop to accurately measure ionizing radiation are focussed on industry/societal needs and therefore are directly relevant to this goal. In addition, we have a responsibility as an ionizing radiation metrology community for personal sustainability, and therefore CCRI is active in reviewing how we can operate more efficiently, e.g., through simpler comparison protocols and CMC reviews, partnering with collaborators to make better use of radiation facilities, and continuing to engage with end-users to ensure the rapid and accurate transfer of knowledge and technology.

For more details on CCRI activities see https://www.bipm.org/en/committees/cc/ccri.

Article written for the SSDL Newsletter No. 79, May 2024

New physicist starts in the BIPM IR Department

2024-05-06T07:28:40Z

Dr Anna Villevalde joined the Ionizing Radiation Department as a dosimetry physicist in April 2024.

Before joining the BIPM, Dr Villevalde worked at the D.I. Mendeleyev Institute for Metrology (VNIIM) since 2006 as a researcher responsible for primary standards in ionizing radiation dosimetry, focusing on low- and medium-energy x-rays, gamma rays and brachytherapy. She actively contributed to the Consultative Committee for Ionizing Radiation (CCRI) Section I and the CCRI Communication Working Group, representing COOMET. Additionally, she served as the technical secretary of COOMET's Technical Committee for Ionizing Radiation since 2015 and as the dosimetry activity coordinator since 2021.

In her new role at the BIPM, Dr Villevalde will oversee all key comparisons and calibrations in x-ray dosimetry, continuing the legacy of excellence established by her predecessor, Dr David Burns.

International Workshop on Alpha Emitter Therapy held at the BIPM

2024-03-14T11:27:44Z

Radiopharmaceutical therapy using alpha-emitting radionuclides such as 223Ra and 225Ac is proving to be highly effective in fighting several forms of cancer. The safe and effective use of these types of drugs relies on the ability to make accurate measurements of the amount of the drug, measured clinically as the amount of radioactivity, being administered to the patient. Because of the complicated decay characteristics and chemical properties of the radionuclides currently under clinical investigation, there are many hurdles to making traceable measurements of the radioactivity content in these types of drugs. To start addressing these issues, the CCRI Radionuclide Therapy and Quantitative Imaging Working Group recently organized an international workshop and webinar at the BIPM to bring together clinical practitioners, metrologists, and representatives from the manufacturing community to discuss measurement needs and potential solutions. The workshop was co-organized with the EURAMET AlphaMet project.

The two-day hybrid workshop was attended by 60 in-person attendees and 235 people worldwide who participated online, making it the most significant CCRI event to date in terms of attendance. A total of 25 invited talks were presented in person by internationally recognized experts in widely diverse areas such as radiopharmaceutical development, isotope production, clinical nuclear medicine, and radionuclide metrology to develop a common understanding of each field’s capabilities and where specific measurement problems exist. Some important topics discussed were clinical applications of targeted alpha therapy (TAT), production and availability of alpha-emitting nuclides relevant to nuclear medicine, dosimetry protocols for TAT, the need for primary and secondary standards for radioactivity measurement, and measurement traceability.

A significant output of the workshop will be a paper describing the workshop that includes a set of recommendations for ways in which the metrology community can address measurement needs expressed by their clinical counterparts.

Radionuclide metrology highlighted in Nature Physics

2023-12-11T13:27:44Z

In the August 2023 edition of Measure for Measure in Nature Physics, Dr Carine Michotte took the readers on a journey through a condensed history of radionuclide metrology, starting from its remarkable inception in 1913 – when Marie Curie introduced the first international standard for Ra-226 at the BIPM – and spanning to activity measurement standards, logistical challenges of comparison exercises for short-lived radionuclides, and glimpses of the BIPM travelling activity comparator. Driven by the emergence of new applications in nuclear medicine and corresponding standardization updates, the BIPM and several regional metrology organizations are currently exploring practicable solutions to address the growing demand for comparisons of radionuclides activity measurement.

Radionuclide activities | Nature Physics

Executive Summary for the CCRI (Recommendations and Actions)

2023-08-11T10:13:24Z

The CCRI was held at the Pavillon du Mail at the BIPM headquarters in Sèvres, France, and was well attended in person (36 participants) and additionally had online participation (30 attendees). This was the first in person meeting of the CCRI since the global pandemic was declared in 2020. The meeting was chaired by the new CCRI president JT Janssen from NPL. The following list outlines the recommendations, in addition to those issued from the Sections, and actions noted from the one and a half days of the 29th meeting of the CCRI.

The Joint Committee of the Regional Metrology Organizations and the BIPM (JCRB) made a recommendation to the CCRI that given the availability in the KCDB (the key comparison database) of a unique and persistent identifier for each CMC (and each version of a CMC), all participating National Metrological Institute or Designated Institute (for example in their quality documentation) are recommended to use these CMC identifiers and asks the BIPM to make available appropriate training material to encourage this practice.
Following decisions made at the 26th meeting of CCRI, small changes to membership rules to the CCRI are proposed. As a reminder, membership is decided by the CIPM and is open to Institutions of Member States that are recognized internationally as the most expert in the field. Institutes which are member of at least 2 CCRI sections can be Members of CCRI, and institutes are member in 1 CCRI section can become official Observers of CCRI. Institutes meeting these requirements are invited to apply for Member or Observer status by sending a letter to the BIPM director.
For Sections, only Institutes names will be kept on the BIPM webpages (no more individual names). In addition, only two types of status will be possible for CCRI Sections, Member or Guest, and the Observer status will be abolished. The number of participants to Section meetings will be limited to 2 to 3 per member depending on the approval by the Section Chair.

CCRI Section II meeting - 2023

2023-08-11T09:21:06Z

The CCRI Section II (Measurement of Radionuclides) met at the BIPM in Sèvres on 5-7 June 2023. There were 24 members and guests meeting in person, and an additional 19 total at various times virtually. The first half-day was held jointly with the KCWG(II).

The main recommendations and actions from this meeting were:

The opening of the BIPM(II)-K5 comparison, following the successful 60Co study, using the ESIR (the extension of the SIR to beta and alpha emitters) with 11 possible radionuclides in the first quarter of 2024.
The development of RMO-based SIRTIs, as they will be very good additions to facilitate the comparison of short-lived isotopes for countries geographically very far from the BIPM. For RMOs seeking to develop such a detector, four conditions were adopted so that the detector and its use would mirror the BIPM-based SIRTI.

Lisa Karam (NIST) is the current chair of CCRI(II), which was renewed until 2025. A request was made for a new Vice-Chair for CCRI(II) (succeeding Freda Van Wyngaardt) who is intended to become the Chair following the CCRI(II) 2025 meeting.

CCRI Section I meeting – 2023

2023-08-11T09:16:45Z

The CCRI(I) was held from 1 to 2 June 2023 at the Vienna International Centre in conjunction with the IAEA SSDL (Secondary Standard Dosimetry Laboratories) Network meeting the 29 and 30 of May 2023. A Joint IAEA-SSDL CCRI(I) one day workshop was organized between the two meetings to enhance the links between the two communities. All these events provided online participation. 40 attendees of CCRI(I) were in-person at the IAEA , with 15 attending virtually.

Malcolm McEwen (NRC, Canada) is the current chair of CCRI(I) and has been renewed until 2027.

The following list outlines the recommendations and actions noted from the summary of this meeting.

The KCWG(I) (Key Comparison Working Group of section 1) is requested to produce a “how far does the light shine” guidance document to link comparisons with CMCs.
The KCWG(I) is requested to provide guidance on updating measurement standards (if not done at time of a Key Comparison).
The BSWG(I) (Brachytherapy Standards Working Group) should be reformed to discuss options for Low Dose Rate (LDR) brachytherapy comparisons.
The joint SSDL/CCRI(I) meeting should be repeated, when possible; likely date is 2029 (due to meeting cycles of the two groups).

A follow-up virtual meeting was held the 29 of June 2023 to review the Vienna meeting discussions and make final decisions on potential actions proposed.

CCRI Section III meeting - 2023

2023-08-11T09:22:41Z

Section III (neutron metrology) of the CCRI held its 27th meeting from 9th to 12th May 2023 at the BIPM in Sevres. 33 participants, 14 of them online, discussed during 3 full days the ongoing activities and future needs of neutron metrology.

One focus of the meeting was the discussion about ongoing and planned comparisons and the related long-term strategy within the CCRI(III). One conclusion of the discussions was that it is necessary to find and implement ways to limit the duration of key and supplementary comparisons organised within the CCRI(III). It was noted that the long delays, sometimes several years, in the completion of comparisons are mostly due to the increased logistical problems associated with sending around radioactive sources and transfer devices and it was decided for the upcoming CCRI(III).K8 comparison to run two transfer instruments in parallel in two separate groups.

Another issue raised during the meeting was the need to establish traceable metrology for neutron energies above 20 MeV, the upper limit of the well-established range. This is motivated by the need for dosimetry in mixed high energy radiation fields which is relevant for aircrew dosimetry, for space missions and for dosimetry of patients treated with modern forms of radiotherapy using protons and heavy ions. Therefore, it was decided to create a CCRI(III) task group “metrology for high energy neutrons” with the aim of increasing communication and interaction between metrology institutes, institutes with suitable facilities and stakeholders interested in this field through a potential workshop to be organised in 2024 or early 2025.

Creation of the CCRI Digital SI Task Group

2023-08-11T09:20:02Z

The Resolution 2 of the 27th CGPM on the Global digital Transformation and the International System of units encouraged the CIPM to continue its outreach and engagement initiatives to ensure that the Metre Convention naturally extends its role as the globally accepted anchor of trust for metrology into the digital era and to undertake the development and promotion of an SI Digital Framework.

The CCRI therefore decided to create a Task Group on digital transformation aiming to advise the CCRI on the SI Digital Framework and the wider implications of the global digital transformation for ionising radiation metrology, as well as to act as a forum to exchange information on progress and to create synergies and opportunities for collaboration in this field.

In this wider context, the TG will focus on the following specific short-term priorities:

Kind of quantities identification in view of the digitalisation of service categories of the KCDB.
Discuss how “digital traceability chain” could be implemented for applications in the three sections.
Collect use cases and user needs from the three sections.

The TG is chaired by Romain Coulon (BIPM IR Department) and includes two representatives from all three of the CCRI sections and one representative from the ICRU, the IAEA/WHO SSDL network and the LNHB/DDEP group with appropriate expertise.

The scope and membership of the TG will be reviewed by CCRI at its biennial meetings in the light of progress and the wider developments of the Digital SI (liaising as appropriate with the CIPM Digital-SI forum)

2023 Randall S. Caswell Award: Dr Lisa Karam

2023-06-28T09:38:21Z

Dr Lisa Karam, the Chair of CCRI Section II: Measurement of radionuclides, was presented with the 2023 Randall S. Caswell Award by the US Council on Ionizing Radiation Measurements and Standards (CIRMS).

The award is in recognition of Dr Karam’s distinguished achievements in the field of Ionizing Radiation Measurements and Standards since beginning her career as a research chemist at NIST in 1983. From 2003 to 2017 she served as Chief of the Radiation Physics Division, playing a pivotal role in NIST’s international interactions in radionuclide metrology. Her research interests encompass radioactivity and dosimetry measurements, particularly in nuclear medicine and radiation therapy, as well as the establishment of an international infrastructure for metrology of ionizing radiation. Dr Karam has co-authored over 65 peer-reviewed papers on the measurement, standards and use of ionizing radiation during her four decades of activity.

“The Caswell Award of CIRMS is reserved for those scientists who have made special contributions to radiation measurements and standards in the US. Lisa was selected because of her leadership in CIRMS over the past two decades in all aspects of the organization. Lisa’s legacy at NIST will be her advocacy with the US Congress and the NIST administration for the major modernization of the radioactivity and radiation dosimetry facilities reflected in the new Radiation Physics Building at NIST.” Bert Coursey (formerly NIST)

The BIPM joins in congratulating Dr Karam for her extensive and successful involvement in ionizing radiation metrology research and development.

Randall S. Caswell Award webpage

Dr Karam receiving the Randall S. Caswell Award from Spencer Mickum, CIRMS former President.

Message from former CCRI President Martyn Sené

2023-03-28T08:06:00Z

The end of March 2023 marks the end of my term as a Member of CIPM and President of CCRI, as well as my retirement from NPL (the UK’s NMI).

It has been a privilege to be President of CCRI and to work with such an active and committed community of metrologists from across the globe; committed to metrology and committed to ensuring its benefits are realized in the enormous number of applications of Ionizing Radiation.

I am grateful to everyone who has supported me in my role and who has contributed to the work of CCRI; those who have participated in our main meetings, sections, WGs and TGs and the wider community actively involved in the comparisons, which are the foundation of the global consistency of IR measurements. My thanks to all of you who have been involved in the leadership of our WGs and TGs for the time you have given to our work and particularly to Malcolm, Lisa and Andreas in their vital and time consuming roles as Chairs of the three Sections.

The role of President would be impossible without the support an Executive Secretary and I have been very fortunate to have been supported by two excellent Secretaries Steven Judge and Vincent Gressier (who prior to this role was Chair of Section III). I want to thank them for their support and also for their leadership of the technical work at the BIPM, which is recognised by the IR community as vitally important and critical for confidence in IR metrology.

As I highlighted in my report at the CGPM in 2022 and in the CIPM meeting earlier in March 2023, there are a lot of important items on the CCRI agenda for the coming years. Activities already under way that need to continue are reflected in our WGs and TGs, in the work under way with CCQM to support the use of Mass Spectrometry in IR applications, and in our new communications group; maximizing the benefits of new communications technologies for collaboration and Knowledge Transfer. But there are also new challenges, including developments in areas such as nuclear power (new small modular fission reactors and a move to accelerate commercialization of fusion). The CCRI will also need to contribute to the wider Digital Agenda of CIPM; ensuring we understand how best to digitize what we do and how we respond to the increasing use of digital technology in applications of IR. I am grateful to Romain Coulon for chairing the new TG in this area. The next few years will also see the development by the CIPM of a new Vision for BIPM and the SI to mark the 150th Anniversary of the Metre Convention in 2025; something that all the CCs will need to contribute to.

With such a full, important and exciting agenda, I am delighted that J.-T. Janssen will be succeeding me as President of CCRI. I have worked with J.-T., who is Chief Metrologist at the NPL, for many years. I know his scientific and technical skills, his commitment to metrology and his commitment to ensuring its benefits are realized will be a major asset for the CCRI community. I wish him and all the CCRI community the best for the coming years.

Martyn Sené

Advances in traceability for nuclear medicine

2023-03-24T15:15:24Z

Validation work is continuing for the International Reference System for α- and pure β-emitting radionuclides (ESIR) in anticipation of a significant expansion of the therapeutic use of radiopharmaceuticals.

The CCRI 2018-2028 Strategy and underlying stakeholder consultation predicted a significant expansion of the therapeutic use of radiopharmaceuticals. This motivated an extensive analysis of the status of primary radioactivity standards underpinning metrological traceability for nuclear medicine. Recently published as a review in Metrologia, the study conducted by experts from the BIPM, NPL, NIST and the International Atomic Energy Agency (IAEA) reached important conclusions regarding:

the implementation by the radionuclide metrology community of a robust system to cross-check primary standards of radionuclides used world-wide in nuclear medicine.
the realization accuracies of existing primary standards and their conformance probability with different tolerances required by medical imaging or therapy applications.
the absence of comparisons for some radionuclides used for single photon emission computerized tomography (SPECT-CT), for positron emission tomography (PET) and for in vitro diagnostics.
in certain cases, the lack of formal evidence that primary standards have been realized.

This situation also applies to candidate species for next-generation radiopharmaceutical products. In this context, the opportunity is now with the radionuclide metrology community to collaboratively work with concerned parties to prioritize the study of these materials. In the same context, CCRI-Section II initiated the development of a new international reference system for α- and pure β-emitting radionuclides (ESIR). The ESIR enables metrology institutes to evaluate the international equivalence of targeted particles used in medical diagnosis and treatments. Based on liquid scintillation counting, the ESIR shall:

for α-emitting standards (actinium, terbium, astatine) enable bilateral comparisons of low activity sources therefore reducing the amount of work required by the strict conditions for shipment and manipulation of radioactive solutions.
for pure β-emitting standards (yttrium, strontium, scandium, erbium) enable bilateral comparisons hence reduce the drive for complex large-scale exercises that overburden the piloting laboratories.
provide traceability services for standards employed in Auger-therapy (erbium, lanthanum).

Validation work on the ESIR is currently in progress, based on a CCRI(II) pilot study completed in 2023. A list of radionuclides is being established and will be discussed at the upcoming meeting of CCRI(II) and by its Key Comparisons Working Group to progressively open the new service.

CCRI-CCQM Workshop on the Use of Mass Spectrometry in Radionuclide Metrology

2023-01-10T14:52:36Z

This online workshop is open to experts and stakeholders from both radionuclide metrology and inorganic chemical analysis communities with experience or interest in using mass spectrometry to support metrological analysis of radioactive elements in applications such as nuclear power, environmental stewardship, forensics and medicine, and the nuclear data supporting the counting methods used in radionuclide metrology. In particular, we look forward to the synergy of CCQM’s expertise in mass spectrometry and CCRI’s expertise in radionuclide materials analyses in guiding our discussions on the most suitable methodologies.

To set the stage, short video “tutorials” – on topics such as using mass spectrometry to resolve data issues with long-lived radionuclides; counting methods used in radionuclide metrology; proper usage of mass spectrometry instrumentation in analysing radioactive materials – will be made available.

We are looking forward to a dynamic meeting!

Please find more details and the registration link on the dedicated webpage.

BIPM workshop on digital electronics for the RMO SIRTIs on 8 June 2022

2023-02-28T12:31:43Z

The workshop was aimed at people from RMOs who have developed, are developing or wish to develop digital electronics suitable for a RMO SIRTI comparison based on a NaI(Tl) well counter.

The objective of this workshop with 35 participants from 16 NMIs/DIs was to :

define the needs by discussing techniques for accurate live-time corrections
share experience with different digital electronics and discuss the advantages and disadvantages
present developments for discussion
establish a list of the most suitable solutions for the RMO SIRTI.

The different presentations are available on the workshop webpage.

In view of the interest in this topic shown by the participants, it is envisaged to continue the discussions at a future event.

A secondment opportunity opened in 2023 at the BIPM Ionizing radiation department

2023-02-28T12:27:17Z

The BIPM is looking for a scientist with experience in radionuclide metrology for the development of a new, high precision method to compare primary standards of alpha-emitting radionuclides.

Please contact the Department Director, Dr Vincent Gressier, to discuss the project and confirm whether the secondment opportunity is still available. Further information available here.

Creation of a Task Group at CCRI on radioactive sources and alternative technologies

2022-08-30T06:46:41Z

Radioactive sources are at the heart of CCRI activities, whether it is a reference field for the calibration of instruments, an unknown sample that needs to be identified and standardized, or a check source that monitors system stability. However there are pressures from several different directions to reduce the use of radioactive sources in ionizing radiation applications, replacing them with other technologies. To study the impact of such an evolution on ionizing radiation metrology, the CCRI decided to create a task group dedicated to this issue with representatives from each section of the CCRI and from source suppliers, with the following main objectives:

review the report from the US National Academies of Sciences, Engineering and Medicine on “Radioactive Sources: Applications and Alternative Technologies” and identify the potential impact on ionizing radiation metrology,
review the current and future requirements for radioactive sources within the activities of CCRI, including the options for non-source-based alternatives,
produce a report summarizing this review and make recommendations to the CCRI for strategic activities to ensure that a robust international system of standards and calibration capabilities within the field of ionizing radiation can be maintained.

This task group held its first meeting on 17 May 2022 and will present its conclusions at the next CCRI meeting in June 2023.

The Measurement Methods Matrix (MMM) available at the CCRI webpage

2022-07-06T15:20:47Z

The KCWG(II) has posted the Measurement Methods Matrix (MMM), as a tool for evaluating CMCs in radioactivity, on the BIPM website.

In the interest of supporting the calibration and measurement capabilities (CMCs) published by National Measurement and Designated Institutes (NMIs and DIs) on the Key Comparison Database (KCDB), the Consultative Committee on Ionizing Radiation Section II [CCRI(II)] developed a generic groupings table of radionuclides called the MMM. Using these groupings, CCRI(II) and corresponding technical committees in the Regional Metrology Organizations (RMOs) might leverage a select set of comparisons to support a wider range of CMCs for the measurement of radionuclides. The MMM has been designed for used by the NMIs and DIs.

For the official rules to CMC claims, refer to the latest “Rules for entering CMC Claims in Ionizing Radiation Metrology” located on the BIPM website: https://www.bipm.org/en/committees/cc/ccri/publications.

The MMM is meant to be used as a tool for evaluating CMCs but should not be construed to imply traceability of radionuclides, which still requires an unbroken chain of comparisons or calibrations against an appropriate standard.

World Metrology Day

2022-05-20T14:25:11Z

The Henri Becquerel National Laboratory (LNHB) at @CEA-List is participating in the World Metrology Day! Two videos are available in English. Other videos are available in French on the LNHB website (http://www.lnhb.fr/categorie/actualite/#journee-mondiale-de-la-metrologie-2022).

The LNHB is the French national laboratory for metrology in the field of ionizing radiation. As such, it belongs to the French national metrology network, led by the France's National Metrology Institute (LNE).

Creation of the CCRI Communication working group

2023-05-09T07:37:54Z

The value of the range of communication channels the CCRI can use to engage, inform and support the Ionizing Radiation (IR) community has been demonstrated in the last years; in particular electronic communication (Webinars, e-learning, Blog, Newsletter, YouTube).

Although this is led, coordinated and mostly resourced from the BIPM work programme, it would be valuable to ensure that the communication plan reflects the needs of the IR community.

A CCRI working group has therefore been created, chaired by the CCRI Executive Secretary to help:

plan and shape communication activities, taking advantage of the networks of the group members
provide input and insights on the needs and interests of the whole IR community (e.g. reflecting different regions, NMI size, maturity of metrology systems etc.)
enable young metrologists to communicate their work.

The members of the CCRI communication working group are as follows: Reham Hamdy (NIS) for AFRIMETS, Anna Villevalde (VNIIM) for COOMET, Paula Toroi (STUK) for EURAMET, Elham Al Fares (Calibration laboratory of Kuwait) for GULFMET, Raphael Galea (NRC) for SIM, Haoran Liu (NIM) for APMP, Freda Van Wyngaardt (ANSTO) for both APMP and Section 2, Massimo Pinto (ENEA) for Section 1, Andreas Zimbal (PTB) for section 3, Romain Coulon and Vincent Gressier (BIPM).

This WG first met February 28 with introduction from Martyn Sené, CCRI president, and will prepare several communication projects and events in the coming months.

ICRM Low-Level Radioactivity Measurement Techniques (LLRMT) Conference

2022-04-01T11:59:40Z

The Low-Level Radioactivity Measurement Techniques (LLRMT) 2022 conference will take place at Gran Sasso National Laboratory (LNGS), Italy, on 2-6 May 2022.

Version 2.0 of the CCRI Strategy

2021-09-29T13:11:54Z

The CCRI Strategy provides an overview of the CCRI strategy to 2028 and beyond. The strategy was developed by CCRI members in consultation with the wider ionizing radiation metrology community and key stakeholders and was first published in 2018.

Strategies such as this need to be living documents. Hence this second version, adopted by the CCRI in June 2021, updates the strategy to reflect new developments in the field of ionizing radiation metrology and in our stakeholder community. It also responds to a wider strategic review being undertaken by the CIPM.

CCRI Workshop: Metrology for Radionuclide Therapy

2021-04-29T07:09:06Z

Accurate patient dosimetry for radionuclide therapy is a complex task which includes measuring the activity of the radionuclide administered to the patient, determining the distribution of the radiopharmaceutical in the body and estimating the radiation dose delivered. This field, which combines biology, dosimetry and radionuclide metrology, is at an early stage.

The aim of this workshop is to identify the current needs and gaps in metrology. Speakers are from the NIST, the University of Würzburg, the Medical University of Marburg, the NPL and the IAEA.

Register in advance on: https://zoom.us/webinar/register/WN_mXYEvCCvTnSvg82O85_1dA

CCRI Webinar: Cosmic-ray dosimetry

2021-04-20T14:09:23Z

The topic of the CCRI webinar in April is cosmic-ray dosimetry. The exposure to cosmic radiation is one of the main concerns for space and aviation activities; accurate dosimetry is a challenge for metrology because specific devices and dedicated protocols are required for the characterization of instruments and their calibration.

Please register for the webinar on: https://zoom.us/webinar/register/WN_bIPefrVoRISnw1R2ik7Gxw. After registering, you will receive a confirmation email containing information about joining the webinar.