BIPM.RI(I)-K4, EURAMET.RI(I)-K4.1, EURAMET.RI(I)-K4.2, APMP.RI(I)-K4 and EURAMET.RI(I)-K4.3
MEASURAND Absorbed dose to water
Radiation quality Co-60 beam
Degrees of equivalence represented by Di = (xi -1) and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in mGy/Gy.
Data older than 15 years are no longer included for degrees of equivalence.
BIPM.RI(I)-K4, EURAMET.RI(I)-K4.1, EURAMET.RI(I)-K4.2, APMP.RI(I)-K4 and EURAMET.RI(I)-K4.3
MEASURAND Absorbed dose to water
Radiation quality Co-60 beam
Degrees of equivalence represented by Di = (xi -1) and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in mGy/Gy.
| LABi | Di | Uneg,i | Upos,i | |
|---|---|---|---|---|
mGy/Gy |
mGy/Gy |
mGy/Gy |
||
| LNE-LNHB | -1.9 | 7.8 | ||
| METAS | 1.1 | 10.4 | ||
| PTB | -1.3 | 7.6 | ||
| NPL | 2.3 | 14.2 | ||
| VSL | -3.0 | 10 | ||
| BEV | -0.3 | 8.2 | ||
| GUM | 3.0 | 7.0 | ||
| ARPANSA | -0.5 | 10.2 | ||
| NRC | -0.5 | 6.8 | ||
| BFKH | -3.5 | 9.0 | ||
| NIM | 2.7 | 7.2 | ||
| KRISS | -1.4 | 7.6 | ||
| NMIJ | -4.8 | 8.0 | ||
| NIST | 1.9 | 11.4 | ||
| SCK-CEN | -1.5 | 15.5 | ||
| VINS | 0.0 | 14.4 | ||
| BRMD, DMSc | 1.8 | 10.8 | ||
| BARC | 3.2 | 11.0 | ||
| PTKMR-BATAN | 2.3 | 18.8 | ||
| NRSL/INER | -1.9 | 8.2 | ||
| NIS | 0.3 | 14.2 | ||
| SSM | 1.2 | 9.1 | ||
| DSA | 2.2 | 9.7 | ||
| STUK | 2.4 | 9.1 | ||
| DTU | 1.6 | 11.5 | ||
| CIEMAT | 0.2 | 10.7 | ||
| IAEA | -0.2 | 10.3 |
Data older than 15 years are no longer included for degrees of equivalence.
| Metrology area, Sub-field | Ionizing Radiation, Section I (x and gamma rays, electrons) |
| Description | Measurement of absorbed dose to water for Cobalt 60 |
| Time of measurements | 1993 - |
| Status | Continuous, approved for equivalence |
| References |
Technical Protocol for ongoing BIPM Dosimetry comparisons International framework of traceability for radiation dosimetry quantities |
| Measurand | Absorbed dose to water relative to the BIPM evaluation |
| Parameters | Radiation type: Co-60 Therapy |
| Transfer device | Ionization chambers |
| Comparison type | Key Comparison |
| Consultative Committee | CCRI (Consultative Committee for Ionizing Radiation) |
| Conducted by | BIPM (Bureau International des Poids et Mesures) |
| Comments | The Final Report for each bi-lateral comparsion is listed in the tab "Participants" Most recent update of results made on 30 June 2025 Results older than 15 years are no longer considered valid |
| Pilot institute |
BIPM
Bureau International des Poids et Mesures BIPM - International Organization |
| Contact person | C. Kessler +33 (0) 1 45 07 70 84 |
| Pilot laboratory | |
|---|---|
| BIPM |
Bureau International des Poids et Mesures, BIPM - International Organization, N/A |
| ARPANSA |
Australian Radiation Protection and Nuclear Safety Agency, Australia, APMP |
| 1997 | |
| 2010 | |
| 2020 |
| BEV |
Bundesamt für Eich- und Vermessungswesen, Austria, EURAMET |
| 1994 | |
| 2009 | |
| 2020 |
| BFKH |
Government Office of the Capital City Budapest, Hungary, EURAMET |
| 2001 |
Participated as OMH which became MKEH and subsequently BFKH |
| 2021 |
| ENEA-INMRI |
Istituto Nazionale di Metrologia delle Radiazioni Ionizzanti, Italy, EURAMET |
| 1994 | |
| 2007 |
| GUM |
Glowny Urzad Miar, Central Office of Measures, Poland, EURAMET |
| 2020 |
| KRISS |
Korea Research Institute of Standards and Science, Korea, Republic of, APMP |
| 2022 |
| LNE-LNHB |
Commissariat à l'énergie atomique / Laboratoire National Henri Becquerel, France, EURAMET |
| 1993 | |
| 2003 | |
| 2013 |
| LSDG |
Laboratorium voor Standaarddosimetrie Gent, Belgium, EURAMET |
| 1999 |
| METAS |
Federal Institute of Metrology, Switzerland, EURAMET |
| 2013 |
| NIM |
National Institute of Metrology, China, APMP |
| 2021 |
| NIST |
National Institute of Standards and Technology, United States, SIM |
| 1997 | |
| 2023 |
| NMIJ AIST |
National Metrology Institute of Japan, Japan, APMP |
| 2009 | |
| 2022 |
|
| NPL |
National Physical Laboratory, United Kingdom, EURAMET |
| 1997 | |
| 2007 | |
| 2017 |
| NRC |
National Research Council, Canada, SIM |
| 1998 | |
| 2009 | |
| 2020 |
| PTB |
Physikalisch-Technische Bundesanstalt, Germany, EURAMET |
| 1989 | |
| 2005 | |
| 2015 |
| VNIIFTRI |
Institute of Physical Technical and Radiotechnical Measurements, Rosstandart, Russian Federation, COOMET |
| 2000 | |
| 2009 |
| VSL |
VSL, Netherlands, EURAMET |
| 1993 |
Participated as NMi-VSL which became VSL in 2009 |
| 2000 |
Participated as NMi-VSL which became VSL in 2009 |
| 2005 |
Participated as NMi-VSL which became VSL in 2009 |
| 2017 |
This page proposes print-out on A4 paper (portrait) of the comparison details (best printed out using a black and white printer).
Please, select items to be printed out, then click on "OK" :
BIPM.RI(I)-K4, EURAMET.RI(I)-K4.1, EURAMET.RI(I)-K4.2, APMP.RI(I)-K4 and EURAMET.RI(I)-K4.3
MEASURAND Absorbed dose to water
Radiation quality Co-60 beam
BIPM.RI(I)-K4
The key comparison reference value is the BIPM evaluation of absorbed dose to water (see International framework of traceability for radiation dosimetry quantities).
The degree of equivalence of each laboratory i with respect to the key comparison reference value is given by a pair of terms both expressed in mGy/Gy:
the relative difference Di = (xi - 1) x 1000 and Ui, its expanded uncertainty (k = 2), with Ui = 2ui.
When required, the degree of equivalence between two laboratories i and j can be evaluated by a pair of terms both expressed in mGy/Gy:
Dij = Di - Dj and Uij , its expanded uncertainty (k = 2). The approximation for Uij is explained in section 5 of the Final Report.
Linking EURAMET.RI(I)-K4.1 to BIPM.RI(I)-K4
The linking of EURAMET.RI(I)-K4.1 to BIPM.RI(I)-K4 was made via BEV, LNE-LNHB and METAS, having participated in both comparisons.
The degree of equivalence of each laboratory i participant in EURAMET.RI(I)-K4.1 with respect to the key comparison reference value is given by a pair of terms both expressed in mGy/Gy: Di = (xi - 1) x 1000 and Ui, its expanded uncertainty (k = 2).
Linking EURAMET.RI(I)-K4.2 to BIPM.RI(I)-K4
The linking of EURAMET.RI(I)-K4.2 to BIPM.RI(I)-K4 was made via BEV having participated in both comparisons.
The degree of equivalence of each laboratory i participant in EURAMET.RI(I)-K4.2 with respect to the key comparison reference value is given by a pair of terms both expressed in mGy/Gy: Di = (xi - 1) x 1000 and Ui, its expanded uncertainty (k = 2).
Linking APMP.RI(I)-K4 to BIPM.RI(I)-K4
The linking of APMP.RI(I)-K4 to BIPM.RI(I)-K4 was made via ARPANSA, NMIJ-AIST and PTB having participated in both comparisons.
The degree of equivalence of each laboratory i participant in APMP.RI(I)-K4 with respect to the key comparison reference value is given by a pair of terms both expressed in mGy/Gy: Di = (xi - 1) x 1000 and Ui, its expanded uncertainty (k = 2).
Linking EURAMET.RI(I)-K4.3 to BIPM.RI(I)-K4
VSL provides the link between the key comparison BIPM.RI(I)-K4 and EURAMET.RI(I)-K4.3, having participated in both comparisons. The linking process is described in Section 2.4 of the EURAMET.RI(I)-K4.3 Final Report.
The degree of equivalence of each laboratory i participant in EURAMET.RI(I)-K4.3 with respect to the key comparison reference value is given by a pair of terms both expressed in mGy/Gy: Di = (xi - 1) x 1000 and Ui, its expanded uncertainty (k = 2).
BIPM.RI(I)-K4, SIM.RI(I)-K4, EUROMET.RI(I)-K4, EURAMET.RI(I)-K4.1, EURAMET.RI(I)-K4.2, APMP.RI(I)-K4 and EURAMET.RI(I)-K4.3
MEASURAND Absorbed dose to water
Radiation quality Co-60 beam
xi : ratio of the measurement made at the BIPM by laboratory i to that of the BIPM
ui : combined standard uncertainty of the ratio xi
BIPM.RI(I)-K4 - Laboratory measurements
| Labi | xi | ui | year of measurement | |
| LNE-LNHB | 0.9981 | 0.0039 | 2013 | |
| METAS | 1.0011 | 0.0052 | 2013 | |
| PTB | 0.9987 | 0.0038 | 2015 | |
| NPL | 1.0023 | 0.0071 | 2017 | |
| VSL | 0.9970 | 0.0048 | 2017 | |
| BEV | 0.9997 | 0.0041 | 2020 | |
| GUM | 1.0030 | 0.0035 | 2020 | |
| ARPANSA | 0.9995 | 0.0051 | 2020 | |
| NRC | 0.9995 | 0.0034 | 2020 | |
| BFKH | 0.9965 | 0.0045 | 2021 | |
| NIM | 1.0027 | 0.0036 | 2021 | |
| KRISS | 0.9986 | 0.0038 | 2022 | |
| NMIJ | 0.9952 | 0.0040 | 2022 | |
| NIST | 1.0019 | 0.0057 | 2023 |
SIM.RI(I)-K4 - Laboratory measurements
See SIM.RI(I)-K4 Final report (results older than 15 years)
EUROMET.RI(I)-K4 - Laboratory measurements
See EUROMET.RI(I)-K4 Final report (results older than 15 years)
EURAMET.RI(I)-K4 - Laboratory measurements
| Labi | xi | ui | year of measurement | |
| METAS | 0.9980 | 0.0063 | 2013 - 2015 | |
| BEV | 1.0011 | 0.0057 | 2013 - 2015 | |
| LNE-LNHB | 0.9977 | 0.0052 | 2013 - 2015 | |
| SCK-CEN | 0.9985 | 0.0078 | 2013 - 2015 | |
| VSL | 0.9952 | 0.0058 | 2013 - 2015 | |
| CIEMAT | 1.0023 | 0.0056 | 2013 - 2015 |
EURAMET.RI(I)-K4.2 - Laboratory measurements
| Labi | xi | ui | year of measurement | |
| VINS | 1.0000 | 0.0072 | 2017 |
APMP.RI(I)-K4 - Laboratory measurements
See APMP.RI(I)-K4 Final report for results older than 15 years
| Labi | xi | ui | year of measurement | |
| BRMD, DMSc | 1.0018 | 0.0054 | 2010 | |
| BARC | 1.0032 | 0.0055 | 2010 | |
| NIM | 1.0010 | 0.0050 | 2010 | |
| PTKMR-BATAN | 1.0023 | 0.0094 | 2010 | |
| NRSL/INER | 0.9981 | 0.0041 | 2010 | |
| NIS | 1.0003 | 0.0071 | 2010 |
EURAMET.RI(I)-K4.3 - Laboratory measurements
| Labi | xi | ui | year of measurement | |
| SSM | 1.0012 | 0.0046 | 2022 | |
| DSA | 1.0022 | 0.0049 | 2022 | |
| STUK | 1.0024 | 0.0046 | 2022 | |
| DTU | 1.0016 | 0.0058 | 2022 | |
| CIEMAT | 1.0002 | 0.0054 | 2022 | |
| IAEA | 0.9998 | 0.0052 | 2022 |
