Transcript Document

CCRI(III)/15-17
Report 2013-2015 of the BIPM
Ionizing Radiation Department
CCRI(III)
BIPM, 4-6 March 2015
José M. Los Arcos
CCRI Executive Secretary
IR Department Director
Index
o
IR resources
• Facilities and standards
• Staff
o
Terms of reference
o
Main achievements in 2013-2015
•
•
•
•
Dosimetry
Radionuclides measurements
Thermometry
International coordination
www.bipm.org
2
IR Resources: Facilities and Standards
PROJECT
FACILITY (only 2 irradiation rooms)
PRIMARY STANDARDS
and other equipment
X-rays
Low energy (10-50 kV)
Mammography (20-40 kV)W/Mo,Mo/Mo
Medium energy (100-250 kV)
Free-air ionization chamber FAC-L01
Free-air ionization chamber FAC-L02
Free-air ionization chamber FAC-M01
-rays
60Co
RADIATION
11
Radioactivity
Dosimetry
11
Quantity
Ka
Ka
Ka
(therapy):
Cis-Bio
(0.2 Gy/min)
Theratron1000 (1 Gy/min)
60Co (protection) 10 mGy/h
137Cs (protection) 50 mGy/h
5 Graphite cavity chambers (+ water phantom)
Ka,Dw
Brachytherapy
No 192Ir source:
Travel standards: well & thimble ioniz. chambers
RAKR
High-energy
photon beams
Calorimetry
Source
preparation
60Co+137Cs
ref.+stab.
Chemical handling
Radioactive handling
Metallizing (gold evaporator)
Weighing
 emitters Système International de Référence(SIR)
SIR Transfer Instrument (SIRTI)
Gamma Spectrometry
Transportable graphite calorimeter
Dw
Diverse
Mettler AX
2 Ionization chambers (+ 5 226Ra sources)
NaI(Tl) well-type transportable instrument
HPGe detector
M
Ae
Ae
Ae
 emitters
(pure /-)
Liquid scintillation counting
Triple-to-Double-Coincidence-Ratio system (TDCR)
Beckman, Quantulus, PerkinElmer: (CIEMAT/NIST)
A
A
(-)
(Anti/)Coincidence counting
4-(PC/PPC)-(NaI)
A
SPRT and work thermometer calibration
WTP and Ga fixed points
T
Thermo
Thermometry
metrywww.bipm.org
3
IR Staff
IR Director
José María
LOS ARCOS
Dosimetry
Cecilia KESSLER
(CK)
BSWG(I) Coordinator
David T. BURNS
(DB)
Philippe
ROGER
(PR)
Thermometry
Susanne
PICARD
(SP)
CCAUV , CCT, Exec. Secretary
Designate KCDB Coordinator
www.bipm.org
CCRI Exec. Secretary
ESWG(II) Coordinator
Manuel NONIS
(MN)
Radioactivity
Guy
RATEL
(GR)
Carine
MICHOTTE
(CM)
JCGM-WG1 (GUM)
Scientific Secretary
Sammy
COURTE
(SC)
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Terms of Reference
“Programme of work and budget of the BIPM for the three years 2013-2015”
CIPM, 2012
“CCRI strategic plan for the period 2013- 2023“
with special emphasis on strategic initiatives for the period 2016-2019”
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
Bureau
International des Poids et Mesures
www.bipm.org
 December 2013
5
“PoW and budget of the BIPM for 2013-2015”
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), 60Co and 137Cs -ray beams,
high-energy photon dosimetry, brachytherapy for HDR 192Ir sources
- RI-A2: Radionuclides:
SIR comparisons of  emitters, SIR extension to  emitters (according to ESWG(II)),
SIRTI comparisons for 99mTc and 18F, 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
Bureau
International des Poids et Mesures
www.bipm.org
6
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
Bureau
International des Poids et Mesures
www.bipm.org
7
BIPM Dosimetry Measurements
Low-energy x-rays
radiodiagnostics
standards
Medium-energy
x-rays radiotherapy
standard
BIPM.RI(I)-K2
comparison
BIPM.RI(I)-K3
comparison
Calibrations
Calibrations
137Cs
60Co
radioprotection
standard
radiotherapy and
radioprotection standards
Brachytherapy
transfer standards
High-energy (accelerator)
photon beam
radiotherapy standard
BIPM.RI(I)-K5
comparison
BIPM.RI(I)-K1
comparison
BIPM.RI(I)-K4
comparison
Calibrations
Calibrations
Calibrations
Mammography
standard
BIPM.RI(I)-K8
comparison
BIPM.RI(I)-K7
comparison
Calibrations
Future absorbed
dose standard
Future
BIPM.RI(I)-K9
comparison
Future
calibrations
www.bipm.org
BIPM.RI(I)-K6
comparison
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
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BIPM Dosimetry highlights (2013-2015)
INDICATORS / STATUS
Main achievements in dosimetry
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 (60Co, 137Cs):
BIPM.RI(I)-K1-K4-K5
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57
19
Accelerator photon beams (graphite calorimeter), on-site at the NMIs:
BIPM.RI(I)-K6 : NPL-2013 and NPL & VSL-2014
3
--
3
- 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. 2014
Brachytherapy - 192Ir HDR revision (CCRI(I)-2013 recommendation) BIPM.RI(I)-K8
New protocol for evaluation of DoEs : agreed
- Evaluation and publication of results of 2009-2011 comparisons
--
--
3
- 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 Wair, 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-rays
Construction and characterization of ion. chambers with graphite
and air-equivalent plastic walls
Characterization of new 60Co 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 137Cs and spare
Improvement of data acquisition and safety
Bureau
International des Poids et Mesures
www.bipm.org
9
BIPM activity measurements
Solution preparation
CCRI(II) comparisons
CCRI(II)-K2
Solid source
preparation
Liquid source
preparation
SIR
Primary methods
4-γ PC
LSC methods
BIPM.RI(II)-K1
HPGe
spectrometry
Impurity tests
(gamma)
CIEMAT/NIST
Transfer instrument (SIRTI)
for 99mTc
4-γ PPC
TDCR
BIPM.RI(II)-K4.Tc99m
Transfer instrument (SIRTI)
for 18F
SIR extension to  emitters
NEW in 2014:
BIPM.RI(II)-K4.F-18
NEW (2015):
BIPM.RI(II)-K?
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
www.bipm.org
demand, on-site at the NMI/DI (SIRTI) (99mTc, 18F, … )
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Radionuclide activity highlights (2013-2015)
INDICATORS / STATUS
Main achievements in radionuclides
SIR activity measurements of  emitters:
BIPM.RI(II)-K1
222Rn
- SIR improvements
- development of SIRTI for
18F
99mTc
, 18F
(T½ < 1.8 h)
Reports
20
8
monitoring to evaluate possible correlation on SIR meas.
- Pilot study 2014 : 3H, 14C, 55Fe, 63Ni ,14 NMIs, 4 scintillators,
Contribution of secondee-consultant (ex-CIEMAT) for 6 months
- KCRV evaluation method to be defined
- TDCR developments: 241Am source for Compton mode
- New PerkinElmer counter (Nov.) under acceptance tests
- SIR extension to pure beta emitters (ESIR)
SIR transfer instrument (SIRTI) for
Comparisons / Measurements
BIPM.RI(II)-K4.Tc-99m
BIPM.RI(II)-K4.F-18
(BIPM.RI(II)-K4.F-18)
- preliminary arrangements for C-11
5
2
- Duplicated electronic setup
- Linked to SIR for 18F
- Implemented. Since June 2014: VNIIM, NPL, ENEA.
- 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 2015
- 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
www.bipm.org
- Simplified structure for comparison reports: BIPM.RI(II)-K2.H-3
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Thermometry work (2013-2015)
INDICATOR / STATUS
Thermometry achievements
BIPM internal thermometry calibrations
(new activity since 2009)
Participation in comparisons
www.bipm.org
-
Comparisons
Characterizations
(certificates)
Reports
--
14 work thermometers
18 SPRT(bridge breakdown)
12 study notes
--
--
Pending
(pilot lab)
CCT-K3 (SPRTs)
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International Coordination (2013-2015)
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)
•
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
•
•
•
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
•
BIPM survey of comparison/calibration needs 2014-2019
•
MMC-2014 Workshop (Brdo, Sept.-2014) , INRIM/EURAMET: S.Picard, invited talk
International Organizations
RMOs
NMIs
www.bipm.org
13
THANKS…
IONIZING RADIATION DEPARTMENT
www.bipm.org
14
Key Data: Determination of Wair at the BIPM
Wair – 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 Wair in progress by ICRU Report Committee on Key Data for Dosimetry
• D Burns (BIPM) member of ICRU and of Report Committee
34.03 eV  0.21 % ( k = 1)
Wair determined at the BIPM:
by measuring the total charge produced in a known air volume when a known radiation energy is deposited in the volume…
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

Measure radiation energy per charge using
BIPM calorimeter and ion chamber in NMI
accelerator beams
- Spin-off from BIPM.RI(I)-K6 comparison programme
• Together give Wair as function of beam energy
Normalized current per volume for 13 standards constructed at the BIPM
1.004
Normalized current per volume

BIPM result
published
in 2014 in
Physics in
Medicine
and Biology
1.003
1.002
1.001
1.000
0.999
0.998
0.997
0.996
1
2
3
www.bipm.org
4
5 6 7 8 9
Chamber number
10 11 12 13
15
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) 192Ir sources (would require afterloading
system, shielded laboratory and primary standard) 
High Dose Rate Brachytherapy for Prostate
Cancer
- Implemented setup for comparisons of standards for (HDR) 192Ir
sources, on-site at the NMIs, using travelling reference standards:
* thimble-type ionization chamber
* well-type ionization chamber
Irradiation arrangement for the
thimble-type ionization chamber
Well-type ionization chamber
- Stability of standards requires measurements at the BIPM using:
* a 137Cs check source and
* the 60Co beam
- On-going key comparison BIPM.RI(I)-K8 registered in the KCDB
Recent developments
BIPM.RI(I)-K8
Degrees of equivalence for reference air kerma rate in
- 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
Di / (mGy/Gy)
•
Ir
30
25
20
15
10
5
0
-5
-10
-15
-20
-25
-30
VSL
www.bipm.org
192
NPL
PTB
16
Dosimetry comparisons in (2014)
o 8 series of ongoing key comparisons BIPM.RI(I)-K1 to K8:
-
Diagnostic x-rays including
mammography
Clinical beams: x-rays, 60Co and
medical accelerator
Radiation protection beams:
60Co and 137Cs
Comparisons
•
16 comparisons  1 FTE person
• Possible connection with survey
on comparison/calibration needs
collected in February-2014
www.bipm.org
15
10
5
0
19
92
19
93
19
94
19
95
19
96
19
97
19
98
19
99
20
00
20
01
20
02
20
03
20
04
20
05
20
06
20
07
20
08
20
09
20
10
20
11
20
12
20
13
20
14
GREAT DEMAND IN 2014 !!
Number of comparisons
20
Year
17
New Dw standard for medium-energy X-rays
o
Current approach
•
Existing standards for medium-energy X-rays: free-air ionization chambers
used to determine air kerma (Kair)
 absorbed dose to water (Dw) determined using protocols
•
IAEA recommendation: to calibrate instruments directly in Dw
•
NMIs currently developing appropriate standards
 will drive need for comparisons
o BIPM standard for Dw in medium-energy X-rays
Development of a BIPM standard for Dw is consistent with the
CCRI strategic initiative: to promote transition of standards from Kair to Dw
•
•
Standard will remain the free-air chamber
Conversion from Kair to Dw 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
0.05
0.045
Total
Electron Impact
0.04
Photoelectric
0.035
Spekcalc
0.03
0.025
0
0.02
0.015
0.01
0.005
0
10
20
30
40
Test of ratio air-to-water of
mass attenuation
coefficients
50
60
measured/calculated
additional measurements and calculations
to test interaction coefficients
80
90
100
Pilot
comparison
before end
of 2015
1.04
1.02
–
70
1.06
1.00
0.98
0.96
www.bipm.org
0.94
40
50
60
70
80
90
100
Mean photon energy / keV
110
120
130
18
Absorbed dose to water for high-energy photon beams: BIPM.RI(I)-K6
BIPM.RI(I)-K6 accelerator comparison 2013 with the NPL at 5 and 7 g cm-2
according to the UK dose protocol.
Published
Joint NPL-VSL comparison 2014 at 10 g cm-2 (2014-10).
Draft B
Comparison with NMIJ/AIST prepared  (2015-04)
BIPM primary standard for clinical
accelerator dosimetry
 optimized reproducibility
 time saving
 improved radiation protection
 Used for the first time in the
NPL and VSL 2014 comparisons.
New BIPM remote controlled intensity
monitoring assembly
www.bipm.org
Newly built VSL water calorimeter
mounted on the NPL linac couch.
19
SIRTI EXTENSION TO 18F ( 1.8 h half-life)
75
8
60
6
45
4
30
2
15
0
0
IFIN-HH
LNMRI/IRD
NIM
CNEA
NMIJ
NIST
-60
KRISS
-45
-8
NPL
-30
-6
PTB
-15
-4
LNE-LNHB
-2
IRA
- previously implemented for
(6 h half-life) with
the SIR Travelling Instrument (SIRTI), on-site at the NMI/DI
90
10
MKEH
99mTc
12
BEV
Extension of SIR to short-lived radionuclides:
[Di = (xi - xR)] / (MBq)
•
[Di /xR] / (kBq/MBq)
BIPM.RI(II)-K1.Tc-99m and BIPM.RI(II)-K4.Tc-99m
Degrees of equivalence for equivalent activity of 99mTc
- extended in 2014 to 18F (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 2014
•
18F
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)
•
Future radionuclides:
•
Other registered participants:
11C, 64Cu
ANSTO, BARC, BEV, CNEA, IFIN-HH, KRISS, LNMRI/IRD, NIM, NIST, NMIJ, NMISA, NRC,…
www.bipm.org
20
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
•
3H, 14C, 55Fe, 63Ni
•
4 counters:
Quantulus 1220
sent by the NMIs/Dis
Beckman LSC
•
•
4 scintillators:
UltimaGold, Hisafe 3, BioFluor, IonicFluor
Two volumes: 10 mL and 15 mL
TDCR
Tricarb 2910TR
o Schedule:
•
Reception of ampoules:
•
Measurements at the BIPM: planned  March 2015
•
Analysis of results (method for KCRV) within the ESWG(II) in 2015 ( October 2015)
 until December 2014 (extended)
Delayed: balance breakdown
www.bipm.org
(under revision at Mettler technical headquarters)
21
“PoW and budget of the BIPM for 2013-2015”
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 2016-2019…“
Bureau
International des Poids et Mesures
www.bipm.org
22
“PoW and budget of the BIPM for 2013-2015”
RI-A1: Dosimetry:
- RI-A1-1: x-rays (+ mammography): comparisons and calibrations and
completing a new medium-energy x-rays standard
- RI-A1-2:
60Co
and 137Cs 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 192Ir comparisons based on transfer standards
and piloting a LDR125I seeds comparison.
Bureau
International des Poids et Mesures
www.bipm.org
23
“PoW and budget of the BIPM for 2013-2015”
•
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 99mTc and 18F
SIRTI development for other PET nuclides: 64Cu, 11C, 153S,…
- RI-A2-3:
Maintain primary methods for CCRI(II) comparisons
Provide SIR entries and establish KCRVs
Bureau
International des Poids et Mesures
www.bipm.org
24
“PoW and budget of the BIPM for 2013-2015”
•
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
Bureau
International des Poids et Mesures
www.bipm.org
25