Comparison
Comparison close
Results

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

MEASURAND : SIR equivalent activity of 51Cr

Degrees of equivalence Di and expanded uncertainty Ui (k = 2) expressed in MBq

Red diamonds and black squares: participants in BIPM.RI(II)-K1.Cr-51
Green triangle: participant in APMP.RI(II)-K2.Cr-51 (2004)
The black colour identifies participant's results prior to 1983

Note: the right-hand axis shows approximate relative values only

Comparison
Comparison close
Results

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

MEASURAND : SIR equivalent activity of 51Cr

   
Lab iDiUi
 / MBq/ MBq
IRMM-4.12.5
CMI-IIR0.72.7
MKEH-0.72.6
PTB-0.42.0
NIST1.43.0
NMIJ-0.93.1
NPL-1.06.2
LNE-LNHB1.22.3
VNIIM0.32.6

In green: participant in APMP.RI(II)-K2.Cr-51

Results are presented under A4 printable format in Summary Results (.PDF file).

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

MEASURAND : SIR equivalent activity of 51Cr

  • Key comparison BIPM.RI(II)-K1.Cr-51

Key comparison reference value:
The SIR reference value for this radionuclide is xR = 488.0 MBq, with a standard uncertainty uR = 0.3 MBq, see section 4.1 of the Final Report dated January 2009.

The degree of equivalence of each laboratory with respect to the key comparison reference value is given by a pair of terms:
Di = (xi - xR) and Ui, its expanded uncertainty (k = 2), both expressed in MBq. With n the number of laboratories, when each laboratory has contributed to the computation of xR, see Metrologia, 42, 140-144.

The degree of equivalence between two laboratories is given by a pair of terms:
Dij = Di - Dj = (xi - xj) and Uij, its expanded uncertainty (k = 2), both expressed in MBq. The approximation Uij ~ 2(ui2 + uj2)1/2 is used for the computation of the pair-wise degrees of equivalence.
  • 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 to the value of NMIJ as the linking laboratory (see Final Report dated October 2005).

The degree of equivalence of laboratory i participant in APMP.RI(II)-K2.Cr-51 with respect to the key comparison 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 Matrix of equivalence.

The degree of equivalence between two laboratories i and j is given by a pair of terms: Dij = Di - Dj and Uij, its expanded uncertainty (k = 2), both expressed in MBq, where the approximation Uij = 2(ui2 + uj2 - 2ful2)1/2 is used (l is the NMIJ and f the correlation coefficient).
These statements make it possible to extend the BIPM.RI(II)-K1.Cr-51 Matrix of equivalence to the participant in the APMP.RI(II)-K2.Cr-51 comparison.
Comparison
Comparison close
Results

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

MEASURAND : SIR equivalent activity of 51Cr

  • Key comparison BIPM.RI(II)-K1.Cr-51

xi : result of measurement carried out in the SIR for the sample submitted by laboratory i
ui
: combined standard uncertainty of xi

 Lab i xi
/ MBq
ui
/ MBq
Date of measurement
 IRMM 483.9 1.1 1981-06-17
 CMI-IIR 488.7 1.4 1982-06-30
 MKEH 487.3 1.3 1989-10-09
 PTB 487.6 0.9 1998-04-24
 NIST 489.4 1.4 1999-05-03
 NMIJ 487.1 1.6 2004-03-15
 NPL 487.0 3.4 2004-05-28
 LNE-LNHB 489.2 1.1 2006-07-17
  • Key comparison APMP.RI(II)-K2.Cr-51

xi : result of measurement carried out at laboratory i, converted to the equivalent activity through the NMJ SIR measurement (see Final Report dated October 2005)
ui
: combined standard uncertainty of xi

 Lab i xi
/ MBq
ui
/ MBq
Date of measurement
 VNIIM 488.3 1.2 2004