Comparison
Comparison close
Results

BIPM.RI(II)-K1.Cr-51, APMP.RI(II)-K2.Cr-51 and EURAMET.RI(II)-K2.Cr-51

MEASURAND : Equivalent activity of Cr-51

 

Degrees of equivalence represented by Di = (xI - xR) and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in MBq.

Cr-51
Di / MBq
Participating institutes

Results in absolute values

Degrees of equivalence represented by Di = (xI - xR)/xR and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in kBq/MBq.

Cr-51
Di / kBq/MBq
Participating institutes

Results in relative values

Comparison
Comparison close
Results

BIPM.RI(II)-K1.Cr-51, APMP.RI(II)-K2.Cr-51 and EURAMET.RI(II)-K2.Cr-51

MEASURAND : Equivalent activity of Cr-51

 

Degrees of equivalence represented by Di = (xI - xR) and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in MBq.

LABi Di Uneg,i Upos,i
MBq
MBq
MBq
NMIJ -0.9 3.1
NPL -1.0 6.7
KRISS 0.4 4.7
POLATOM -4.4 5.9
VNIIM 0.8 2.5
LNE-LNHB -1.6 3.2
Participating institutes
BIPM.RI(II)-K1.Cr-51
APMP.RI(II)-K2.Cr-51
EURAMET.RI(II)-K2.Cr-51

Results in absolute values

Degrees of equivalence represented by Di = (xI - xR)/xR and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in kBq/MBq.

LABi Di Uneg,i Upos,i
kBq/MBq
kBq/MBq
kBq/MBq
NMIJ -1.9 6.3
NPL -2 14
KRISS 0.7 9.7
POLATOM -9 12
VNIIM 1.6 5.1
LNE-LNHB -3.2 6.6
Participating institutes
BIPM.RI(II)-K1.Cr-51
APMP.RI(II)-K2.Cr-51
EURAMET.RI(II)-K2.Cr-51

Results in relative values

APMP.RI(II)-K2.Cr-51
Metrology area, Sub-field Ionizing Radiation, Section II (Measurement of Radionuclides)
Description Activity of radionuclide Cr-51
Time of measurements 2004
Status Approved for equivalence
Final Reports of the comparisons
Measurand Activity concentration in kBq/g
Transfer device Radioactive solution
Comparison type Key Comparison
Consultative Committee CCRI (Consultative Committee for Ionizing Radiation)
Conducted by APMP (Asia Pacific Metrology Programme)
Comments APMP.RI(II)-K2.Cr-51 results are linked to those of BIPM.RI(II)-K1.Cr-51
First results published on 7 March 2003
Update and APMP data published on 10 October 2005
Update published on 07 February 2009

SIR equivalent activity of the radionuclide 51Cr:
Pilot institute NMIJ AIST
National Metrology Institute of Japan
Japan
Contact person Y. Hino

+81 298 61 5667
First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory
NMIJ AIST

National Metrology Institute of Japan, Japan, APMP

VNIIM

D.I. Mendeleyev Institute for Metrology, Rosstandart, Russian Federation, COOMET

Comparison
Comparison close
Results

BIPM.RI(II)-K1.Cr-51, APMP.RI(II)-K2.Cr-51 and EURAMET.RI(II)-K2.Cr-51

MEASURAND : Equivalent activity of Cr-51

 

BIPM.RI(II)-K1.Cr-51

Key comparison reference value: the SIR key comparison reference value xR for this radionuclide is  xR = 488.05 MBq with a standard uncertainty uR = 0.41 MBq

(see Section 4.1 of the BIPM.RI(II)-K1.I-Cr-51 Final Report).  The value xi is taken as the equivalent activity for a laboratory i.

 

The degree of equivalence of each laboratory i with respect to the reference value is given by a pair of terms:

Di = (x- xR) and Uits expanded uncertainty (k = 2), both expressed in MBq, and

Ui = 2((1 - 2wi)ui2 + u2R)1/2, where wi is the weight of laboratory i contributing to the calculation of xR.

The degrees of equivalence are also given in relative terms by Di = (xI - xR) /xR and its expanded uncertainty Ui at a 95 % level of confidence, both expressed in kBq/MBq.

 

Linking APMP.RI(II)-K2.Cr-51 to BIPM.RI(II)-K1.Cr-51

The value xi is the equivalent activity for laboratory i participant in APMP.RI(II)-K2.Cr-51 having been normalized using the value of the NMIJ as the linking laboratory.

The degree of equivalence of laboratory i participant in APMP.RI(II)-K2.Cr-51 with respect to the reference value is given by a pair of terms:
Di = (xi - xR) and Ui, its expanded uncertainty (k = 2), both expressed in MBq. The approximation Ui = 2(ui2 + uR2)1/2 is used in the following table as none of these Di contributed to the key comparison reference value.

 

Linking EURAMET.RI(II)-K2.Cr-51 to BIPM.RI(II)-K1.Cr-51

The value xi is the equivalent activity for laboratory i participant in EURAMET.RI(II)-K2.Cr-51 having been normalized to the value of the POLATOM as the linking laboratory.

The degree of equivalence of laboratory i participant in EURAMET.RI(II)-K2.Cr-511 with respect to the reference value is given by a pair of terms:
Di = (xi - xR) and Ui, its expanded uncertainty (k = 2), both expressed in MBq. The approximation Ui = 2(ui2 + uR2)1/2 is used in the following table as none of these Di contributed to the key comparison reference value..

These statements make it possible to extend the BIPM.RI(II)-K1.Cr-51 matrices of equivalence to all participants in the APMP.RI(II)-K2.Cr-51 and  EURAMET.RI(II)-K2.Cr-51 comparisons

Comparison
Comparison close
Results

BIPM.RI(II)-K1.Cr-51, APMP.RI(II)-K2.Cr-51 and EURAMET.RI(II)-K2.Cr-51

MEASURAND : Equivalent activity of Cr-51

 

xi   measured mass fraction reported by laboratory iLabi

ui   combined standard uncertainty of xi

 

 

BIPM.RI(II)-K1.Cr-51

  Labi xi ui Date of measurement
    kBq kBq  
  NMIJ 487.1 1.6 2004-03-15
  NPL 487.0 3.4 2004-05-28
  KRISS 488.4 2.4 2012-01-27
  POLATOM 483.6 3.0 2022-06-03

 

APMP.RI(II)-K2.Cr-51

  Labi xi ui Date of measurement
    kBq kBq
  VNIIM 488.8 1.2 2004

 

EURAMET.RI(II)-K2.Cr-51

  Labi xi ui Date of measurement
    kBq kBq
  LNE-LNHB 486.5 1.6 2022