On 7 February 2023 the 19th meeting of TC 1.9 "Ionizing Radiation and Radioactivity" was held online, at which the following persons took part: representatives of 10 COOMET member countries (Azerbaijan, Armenia, Belarus, Bosnia and Herzegovina, Georgia, Kazakhstan, Moldova, Russia, Tajikistan, Uzbekistan), Chair of the Joint Committee for Measurement Standards A. Chunovkina, and Head of COOMET Secretariat N. Liakhova.

The following issues were discussed during the meeting:

• resolutions of the meetings of the COOMET Committee and COOMET President's Council;
• resolutions of the Joint Committee for Measurement Standards, adopted in 2022;
• TC 1.9 activities over the period since the last meeting;
• information about the activities of NMIs of TC 1.9 member countries in the field of measuring ionizing radiation;
• implementation of the current projects, carried out within TC 1.9 and proposal on new projects;
• organization of courses on the BIPM e-learning platform and participation in CCRI webinars;
• extension of powers of the Chairman of TC 1.9 N. Moiseev;
• clarification on the list of COOMET technical experts on CMC review.

Main adopted decision:

1. to recommend to the COOMET Committee to extend the powers of the Chairman of TC 1.9 N. Moiseev (VNIIM, Russia) for 4 years;
2. to continue work on the comparisons within TC 1.9, provided for in the COOMET Development Program, inter alia:
   - complete the publication of the report on comparisons COOMET.RI(I)-S3 "Comparisons of national standards of air kerma for x-radiation qualities used for radiation protection and diagnostic radiology" (project 641/BY-а/14, pilot – BelGIM, Belarus);
   - to conduct the comparison COOMET.RI(II)-S3 "Comparisons of national standards on measuring radioactivity in point sources" (project 833/RU-а/20, pilot – VNIIM, Russia) according to the "beam" scheme with distribution of samples to participants from VNIIM;
   - to send an official request to Cuba about their intention to participate in comparison Comparison of the well-type ionization chamber (IC) calibrations factors for the medical radionuclides ("Dosecalibrators") (topic 389/RU/07) or to change the format of participation to calibration;
3. to complete the preparation of the calibration procedure for gamma spectrometers in 2023 (project 600/RU-а/13, pilot– VNIIM, Russia);
4. after clarification on the possibility of direct traceability of measurement results to SIR, agree on a technical protocol, open the proposed COOMET topic and register the comparisons on measuring the activity of a solution of barium-133 radionuclide;
5. taking into account the past experience and the current situation, to conduct bilateral comparisons in the field of dosimetry with VNIIM or VNIIFTRI upon request (should be formulated and sent from the NMI that needs to conduct such comparisons). These comparisons may be carried out for the needs of NMIs of countries with developing metrological systems (CEEMS).

The next TC meeting is scheduled for autumn 2023 (the venue and format of the event will be decided in due course).