Report of the BIPM Ionizing Radiation Department José M. Los Arcos CCRI Executive Secretary IR Department Director CCRI(III) BIPM, 4-6 March 2015 CCRI(III)/15-17

2www.bipm.org Index o IR resources Facilities and standards Staff o Terms of reference o Main achievements in Dosimetry Radionuclides measurements Thermometry International coordination

3www.bipm.org PROJECT RADIATION FACILITY (only 2 irradiation rooms) PRIMARY STANDARDS and other equipment Quantity Dosimetry X-rays Low energy (10-50 kV) Mammography (20-40 kV)W/Mo,Mo/Mo Medium energy ( kV) Free-air ionization chamber FAC-L01 Free-air ionization chamber FAC-L02 Free-air ionization chamber FAC-M01 Ka Ka Ka Ka Ka Ka  -rays 60 Co (therapy): Cis-Bio (0.2 Gy/min) Theratron1000 (1 Gy/min) 60 Co (protection) 10 mGy/h 137 Cs (protection) 50 mGy/h 5 Graphite cavity chambers (+ water phantom)Ka,DwKa,Dw BrachytherapyNo 192 Ir source: 60 Co+ 137 Cs ref.+stab.Travel standards: well & thimble ioniz. chambers RAKR High-energy photon beams CalorimetryTransportable graphite calorimeter DwDw Radioactivity Source preparation Chemical handling Radioactive handling Metallizing (gold evaporator) Weighing Diverse Mettler AX M  emitters Système International de Référence(SIR) SIR Transfer Instrument (SIRTI) Gamma Spectrometry 2 Ionization chambers ( Ra sources) NaI(Tl) well-type transportable instrument HPGe detector AeAeAeAeAeAe  emitters (pure  /  -  ) (  -  ) Liquid scintillation counting (Anti/)Coincidence counting Triple-to-Double-Coincidence-Ratio system (TDCR) Beckman, Quantulus, PerkinElmer: (CIEMAT/NIST) 4  -  (PC/PPC)-  (NaI) AAAAAA Thermo metry SPRT and work thermometer calibrationWTP and Ga fixed points T 11 IR Resources: Facilities and Standards

4www.bipm.org Sammy COURTE (SC) Carine MICHOTTE (CM) Guy RATEL (GR) Manuel NONIS (MN) Radioactivity Thermometry Dosimetry Cecilia KESSLER (CK) David T. BURNS (DB) Susanne PICARD (SP) Philippe ROGER (PR) IR Staff José María LOS ARCOS IR Director CCAUV, CCT, Exec. Secretary Designate KCDB Coordinator JCGM-WG1 (GUM) Scientific Secretary CCRI Exec. Secretary ESWG(II) Coordinator BSWG(I) Coordinator

5www.bipm.org Bureau International des Poids et Mesures Terms of Reference “Programme of work and budget of the BIPM for the three years ” CIPM, 2012 “CCRI strategic plan for the period “ w ith special emphasis on strategic initiatives for the period ” K. Carneiro CCRI President, CIPM, P. Sharpe, Chairman CCRI(I) L. Karam, Chairman CCRI(II) David Thomas, Chairman CCRI(III) José María Los Arcos, CCRI Executive Secretary Last update  December 2013

6www.bipm.org Bureau International des Poids et Mesures “PoW and budget of the BIPM for ” 4.4. Ionizing Radiation. Activities and deliverables for 2013 to 2015 Overall aim: to continue to provide Member States with the ability to compare, or to characterize, their national standards for dosimetry and radionuclide activity, based on a well defined and stable set of international reference facilities. Activities: - RI-A1: Dosimetry: comparisons and/or calibrations for x-rays (+ mammography), 60 Co and 137 Cs  -ray beams, high-energy photon dosimetry, brachytherapy for HDR 192 Ir sources - RI-A2: Radionuclides: SIR comparisons of  emitters, SIR extension to  emitters (according to ESWG(II)), SIRTI comparisons for 99m Tc and 18 F, SIRTI development for other PET nuclides to maintain primary methods for CCRI(II) comparisons to provide SIR entries and establish KCRVs - RI-A3: Coordination activities: Support to CCRI, CCAUV, JCGM-WG1 (GUM), Participation in international organizations/committees: ICRU, ICRM, IAEA (  No neutron measurement activities )

7www.bipm.org Bureau International des Poids et Mesures Terms of Reference Additionally, the IR is responsible for the BIPM internal service of thermometry: RI-A4: Thermometry: - calibration of standard platinum resistance thermometers and laboratory thermometers for the Departments of Mass, Electricity, Chemistry and IR

8www.bipm.org Future absorbed dose standard Future BIPM.RI(I)-K9 comparison BIPM.RI(I)-K5 comparison Calibrations BIPM.RI(I)-K8 comparison Low-energy x-rays radiodiagnostics standards BIPM.RI(I)-K3 comparison Calibrations BIPM.RI(I)-K1 comparison Calibrations BIPM.RI(I)-K4 comparison Calibrations 60 Co radiotherapy and radioprotection standards Medium-energy x-rays radiotherapy standard 137 Cs radioprotection standard BIPM.RI(I)-K2 comparison BIPM.RI(I)-K7 comparison Calibrations BIPM.RI(I)-K6 comparison Brachytherapy transfer standards High-energy (accelerator) photon beam radiotherapy standard Mammography standard BIPM Dosimetry Measurements Future calibrations Summary: 6 on-going comparisons of national primary standards, on demand, at the BIPM 2 on-going comparisons of national primary standards, on demand, on-site at the NMI/DI Calibrations of national secondary standards Summary: 6 on-going comparisons of national primary standards, on demand, at the BIPM 2 on-going comparisons of national primary standards, on demand, on-site at the NMI/DI Calibrations of national secondary standards

9www.bipm.org Bureau International des Poids et Mesures BIPM Dosimetry highlights ( ) Main achievements in dosimetry INDICATORS / STATUS Comparisons Characterizations (certificates) Published reports Low-energy x-ray dosimetry( (ncluding mammography): BIPM.RI(I)-K2-K7 medium-energy x-ray dosimetry: BIPM.RI(I)-K3  -ray dosimetry ( 60 Co, 137 Cs): BIPM.RI(I)-K1-K4-K Accelerator photon beams (graphite calorimeter), on-site at the NMIs: BIPM.RI(I)-K6 : NPL-2013 and NPL & VSL New BIPM remote-controlled intensity-monitoring assembly Better reproducibility, time saving and radiation protection. Implemented in NPL-VSL K6 - Approaches for high-energy photon comparisons at reference facilities Draft document: December 2013 Arrangements for CCRI Workshop in 2015 on accelerator dosimetry Workshop initiative cancelled Nov Brachytherapy Ir HDR revision (CCRI(I)-2013 recommendation) BIPM.RI(I)-K8New protocol for evaluation of DoEs : agreed - Evaluation and publication of results of comparisons New BIPM.RI(I)-K8 comparisons in 2014 on-site at the NMIs: NRC, LNE-LNHB 2-- BIPM comparisons in 2014 : Great demand !! 16 Dosimeter irradiations for IAEA/WHO 12 Key data: re-evaluation of W air, crucial for all primary ionometric dosimetry measurements Published in Physics in Medicine and Biology To be included in ICRU Report on Key Data Development of new absorbed-dose standard for medium-energy x-raysConstruction and characterization of ion. chambers with graphite and air-equivalent plastic walls Characterization of new 60 Co therapy beam (Theratron 1000) Horizontal and vertical profiles Comparison with CisBio beam Calorimetry QA - Construction of primary ionization chamber standards - In-house development and testing LabView acquisition codes for 5 beams 2 constructed and characterized for 137 Cs and spare Improvement of data acquisition and safety

10www.bipm.org BIPM activity measurements Solid source preparation Liquid source preparation Primary methodsLSC methods SIR BIPM.RI(II)-K1 4  - γ PC TDCR CIEMAT/NIST HPGe spectrometry 4  - γ PPC SIR extension to  emitters NEW (2015): BIPM.RI(II)-K? Transfer instrument (SIRTI) for 99m Tc BIPM.RI(II)-K4.Tc99m Transfer instrument (SIRTI) for 18 F NEW in 2014: BIPM.RI(II)-K4.F-18 CCRI(II) comparisons CCRI(II)-K2 Solution preparation Impurity tests (gamma) Summary: 1 on-going comparison for activity of gamma emitters (>60), on demand, at the BIPM (SIR) 1 on-going comparisonson for activity of short-lived radionuclides, on demand, on-site at the NMI/DI (SIRTI) ( 99m Tc, 18 F, … ) Summary: 1 on-going comparison for activity of gamma emitters (>60), on demand, at the BIPM (SIR) 1 on-going comparisonson for activity of short-lived radionuclides, on demand, on-site at the NMI/DI (SIRTI) ( 99m Tc, 18 F, … )

11www.bipm.org Radionuclide activity highlights ( ) Main achievements in radionuclides INDICATORS / STATUS Comparisons / MeasurementsReports SIR activity measurements of  emitters: BIPM.RI(II)-K SIR improvements 222 Rn monitoring to evaluate possible correlation on SIR meas. - SIR extension to pure beta emitters (ESIR) -Pilot study 2014 : 3 H, 14 C, 55 Fe, 63 Ni,14 NMIs, 4 scintillators, Contribution of secondee-consultant (ex-CIEMAT) for 6 months - KCRV evaluation method to be defined - TDCR developments: 241 Am source for Compton mode - New PerkinElmer counter (Nov.) under acceptance tests SIR transfer instrument (SIRTI) for 99m Tc, 18 F BIPM.RI(II)-K4.Tc-99m BIPM.RI(II)-K4.F development of SIRTI for 18 F (T½ < 1.8 h) (BIPM.RI(II)-K4.F-18) - Duplicated electronic setup - Linked to SIR for 18 F - Implemented. Since June 2014: VNIIM, NPL, ENEA. - preliminary arrangements for C-11- project: campaign 2016 at CIEMAT: 6 NMIs interested KCRV determination using the Power ModeratedMean (PMM) method- Implemented in CCRI(II)-2013 Gamma spectrometry - Old Ge(Li) detector: irreversible failure (>25 years old) - Impurity assessment suspended: NMIs to provide data - In progress: efficiency characterization of new HPGe detector (IFIN-HH secondee, 3 months, 2014)) Metrologia Special Issue on uncertainties in radionuclide measurements - Under peer review stage. Publication June Guest Editors:J.M. Los Arcos, L. Karam, J. Keightley - Authorship of 3 chapters: G. Ratel, C., Michotte BIPM primary methods for SIR and CCRI comparisons - New gold-coating machine (received 2013). In operation -4πβ-γ PPC coincidence setups being updated (BIPM to pilot the CCRI(II)-K1.Cd-109 comparison in 2016) Publication of reports: Time optimization - Simplified structure for comparison reports: BIPM.RI(II)-K2.H-3

12www.bipm.org Thermometry achievements INDICATOR / STATUS Comparisons Characterizations (certificates) Reports BIPM internal thermometry calibrations (new activity since 2009) work thermometers 18 SPRT(bridge breakdown) 12 study notes -- Participation in comparisons-CCT-K3 (SPRTs)-- Pending (pilot lab) Thermometry work ( )

13www.bipm.org International Coordination / Cooperation INDICATOR Support to CIPM CCs CCRI Exec. Secretary: J.M. Los Arcos CCAUV Exec. Secretary: S.Picard CCT, ad interim Exec. Secretary: S. Picard Suppport to JCGM/WG1 (GUM) Scientific Secretary: C.Michotte Support to KCDB (in progress) S. Picard: Designate KCDB Coordinator (since February 2015) International Organizations ICRU: Commissioner, Chair of Fundamental Quantities and Units Committee, Member of Key Data Report Committee, D.T. Burns ICRM: Executive Board Member, G. Ratel. ICRM-2013 & ICRM-2015 Scientific Committees IAEA, Scientific Committee of the SSDL network, D.T. Burns RMOs EURAMET TC-IR Meeting (Oslo, Oct.-2014): C. Kessler, invited talk EURAMET TC-T Meetings (Cavtat, Apr.-2014, Lisbonne, Febr.-2015): S. Picard, invited talk Reports of IR regional comparisons published : 13 NMIs BIPM survey of comparison/calibration needs MMC-2014 Workshop (Brdo, Sept.-2014), INRIM/EURAMET: S.Picard, invited talk International Coordination ( )

14www.bipm.org IONIZING RADIATION DEPARTMENT THANKS…

15www.bipm.org Together give W air as function of beam energy Key Data: Determination of W air at the BIPM  Measure charge q per volume V for series of 13 ionization chambers constructed at BIPM - High-accuracy determination of mean value q/V - Spin-off from comparison programmes in x- and  -ray dosimetry BIPM result published in 2014 in Physics in Medicine and Biology W air – mean energy required to create an ion pair in dry air Physical constant required for all ionometric primary standards used worldwide Value used at present was recommended by CCRI in 1985 Re-evaluation of W air in progress by ICRU Report Committee on Key Data for Dosimetry D Burns (BIPM) member of ICRU and of Report Committee W air determined at the BIPM: eV  0.21 % ( k = 1) by measuring the total charge produced in a known air volume when a known radiation energy is deposited in the volume…  Measure radiation energy per charge using BIPM calorimeter and ion chamber in NMI accelerator beams - Spin-off from BIPM.RI(I)-K6 comparison programme

16www.bipm.org Brachytherapy dosimetry at the BIPM: BIPM.RI(I)-K8 CCRI(I) recommended (2008) to implement a BIPM reference for brachytherapy dosimetry comparisons Brachytherapy dosimetry at the BIPM: no primary facility available for (HDR) 192 Ir sources (would require afterloading system, shielded laboratory and primary standard)  - Implemented setup for comparisons of standards for (HDR) 192 Ir sources, on-site at the NMIs, using travelling reference standards: * thimble-type ionization chamber * well-type ionization chamber - Stability of standards requires measurements at the BIPM using: * a 137 Cs check source and * the 60 Co beam - On-going key comparison BIPM.RI(I)-K8 registered in the KCDB Recent developments - After CCRI(I)-2013: * revised protocol for evaluation of DoEs * 3 published results in the KCDB * HDR comparisons resumed: 2 further NMIs in 2014, 1 planned in 2015 High Dose Rate Brachytherapy for Prostate Cancer Well-type ionization chamber Irradiation arrangement for the thimble-type ionization chamber

17www.bipm.org Dosimetry comparisons in (2014) -Diagnostic x-rays including mammography -Clinical beams: x-rays, 60 Co and medical accelerator -Radiation protection beams: 60 Co and 137 Cs o 8 series of ongoing key comparisons BIPM.RI(I)-K1 to K8: GREAT DEMAND IN 2014 !! 16 comparisons  1 FTE person Possible connection with survey on comparison/calibration needs collected in February-2014 GREAT DEMAND IN 2014 !! 16 comparisons  1 FTE person Possible connection with survey on comparison/calibration needs collected in February-2014

18www.bipm.org Development of a BIPM standard for D w is consistent with the CCRI strategic initiative: to promote transition of standards from K air to D w o BIPM standard for D w in medium-energy X-rays Standard will remain the free-air chamber Conversion from K air to D w will make use of transfer ionization chambers – BIPM design of waterproof chamber for use in air and water – using different wall materials to test uncertainties – Monte Carlo calculations for these materials – calculation of x-ray spectra – additional measurements and calculations to test interaction coefficients New D w standard for medium-energy X-rays Pilot comparison before end of 2015 o Current approach Existing standards for medium-energy X-rays: free-air ionization chambers used to determine air kerma (K air)  absorbed dose to water (D w ) determined using protocols IAEA recommendation: to calibrate instruments directly in D w NMIs currently developing appropriate standards  will drive need for comparisons

19www.bipm.org Absorbed dose to water for high-energy photon beams: BIPM.RI(I)-K6 BIPM primary standard for clinical accelerator dosimetry New BIPM remote controlled intensity monitoring assembly  optimized reproducibility  time saving  improved radiation protection  Used for the first time in the NPL and VSL 2014 comparisons. Newly built VSL water calorimeter mounted on the NPL linac couch. BIPM.RI(I)-K6 accelerator comparison 2013 with the NPL at 5 and 7 g cm -2 according to the UK dose protocol. Published Comparison with NMIJ/AIST prepared  ( ) Joint NPL-VSL comparison 2014 at 10 g cm -2 ( ). Draft B

20www.bipm.org Extension of SIR to short-lived radionuclides: - previously implemented for 99m Tc (6 h half-life) with the SIR Travelling Instrument (SIRTI), on-site at the NMI/DI - extended in 2014 to 18 F (the most frequent radionuclide used for imaging by Positron Emission Tomography-PET) - New BIPM.RI(II)-K4.F-18 comparison registered in the KCDB in F Comparisons carried out (all in 2014) - VNIIM, NPL and ENEA - All reports at Draft A stage: * VNIIM and ENEA: pending on their results of primary measurements of activity * NPL: Analysis of results in progress Comparison results linked to the SIR: to be presented at the ICRM Conference in Vienna (June 2015) SIRTI EXTENSION TO 18 F ( 1.8 h half-life) Future radionuclides: 11 C, 64 Cu Other registered participants : ANSTO, BARC, BEV, CNEA, IFIN-HH, KRISS, LNMRI/IRD, NIM, NIST, NMIJ, NMISA, NRC,…

21www.bipm.org Extension of SIR to  emitters o Pilot study 2014 : Defined in the ESWG(II) Goal: to test the cross-efficiency and the apparent efficiency methods 14 NMIs participants 3 H, 14 C, 55 Fe, 63 Ni sent by the NMIs/Dis 4 scintillators: UltimaGold, Hisafe 3, BioFluor, IonicFluor Two volumes: 10 mL and 15 mL Beckman LSC Tricarb 2910TR Quantulus 1220 TDCR 4 counters: o Schedule: Reception of ampoules:  until December 2014 (extended) Measurements at the BIPM: planned  March 2015 Analysis of results (method for KCRV) within the ESWG(II) in 2015 (  October 2015) o Schedule: Reception of ampoules:  until December 2014 (extended) Measurements at the BIPM: planned  March 2015 Analysis of results (method for KCRV) within the ESWG(II) in 2015 (  October 2015) Delayed: balance breakdown (under revision at Mettler technical headquarters)

22www.bipm.org Bureau International des Poids et Mesures “PoW and budget of the BIPM for ” Revised and definitive (budgetary restrictions) after the CGPM “3.5. Ionizing Radiation In the field of dosimetry, budget limitations will result in the postponement of the realization of a high-energy photon dosimetry facility based on a clinical linear accelerator. In the field of radionuclide metrology, the planned extension of the International Reference system (SIR) to alpha emitters will be postponed to the PoW …“

23www.bipm.org Bureau International des Poids et Mesures “PoW and budget of the BIPM for ” RI-A1: Dosimetry: - RI-A1-1: x-rays (+ mammography): comparisons and calibrations and completing a new medium-energy x-rays standard - RI-A1-2: 60 Co and 137 Cs beams: comparisons and calibrations and calorimetric evaluation of absorbed dose - RI-A1-3: high-energy photon dosimetry: off-site comparisons with graphite calorimeter and identifying funding possibilities for a reference facility in the future - RI-A1-4: brachytherapy: HDR 192 Ir comparisons based on transfer standards and piloting a LDR 125 I seeds comparison.

24www.bipm.org Bureau International des Poids et Mesures “PoW and budget of the BIPM for ” RI-A2: Radionuclides: - RI-A2-1: Maintain SIR comparisons of  emitters Maintain  -spectrometry, particularly for impurities measurements Provide SIR comparisons for  emitters (according to ESWG(II)) Construction of a Becquerel chamber (depending on BqWG(II)) Analyze the challenge of low-level activity measurements for 2016-> - RI-A2-2: SIRTI comparisons for 99m Tc and 18 F SIRTI development for other PET nuclides: 64 Cu, 11 C, 153 S,… - RI-A2-3: Maintain primary methods for CCRI(II) comparisons Provide SIR entries and establish KCRVs

25www.bipm.org Bureau International des Poids et Mesures “PoW and budget of the BIPM for ” RI-A3: International Coordination Activities: - Support to CCRI, CCAUV, JCGM-WG1 (GUM) - Participation in international organizations/committees (ICRU, ICRM, IAEA) Additionally, the IR is responsible for the BIPM internal service of thermometry: RI-A4: Thermometry: - calibration of standard platinum resistance thermometers and laboratory thermometers for the Departments of Mass, Electricity, Chemistry and IR