Comparison
Comparison close
Results

EUROMET.RI(II)-K2.Np-237 was placed in the KCDB archives on 12 March 2024

  

BIPM.RI(II)-K1.Np-237 and EUROMET.RI(II)-K2.Np-237

MEASURAND : Equivalent activity of 237Np

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

Red diamonds : participants in BIPM.RI(II)-K1.Np-237
Green triangles : participants in EUROMET.RI(II)-K2.Np-237

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

Comparison
Comparison close
Results

EUROMET.RI(II)-K2.Np-237 was placed in the KCDB archives on 12 March 2024

BIPM.RI(II)-K1.Np-237 and EUROMET.RI(II)-K2.Np-237

MEASURAND : Equivalent activity of 237Np

 

 

     
Lab i Di Ui
  / MBq / MBq
BIPM 0.6 1.6
PTB -0.1 0.3
IRMM 0.1 0.3
LNE-LNHB 0.4 0.5
CIEMAT 0.7 0.8
NPL -0.6 0.9
NRC -0.8 1.7

 

 

In green: participants in EUROMET.RI(II)-K2.Np-237

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

 

Comparison
Comparison close
RMO comparison
Linked comparison
EUROMET.RI(II)-K2.Np-237
Metrology area, Sub-field Ionizing Radiation, Section II (Measurement of Radionuclides)
Description Activity of radionuclide Np-237
Time of measurements 1997 - 2001
Status Approved for equivalence
Final Reports of the comparisons
Measurand Activity
Comparison type Key Comparison
Consultative Committee CCRI (Consultative Committee for Ionizing Radiation)
Conducted by EURAMET (European Association of National Metrology Institutes)
RMO Internal Identifier EUROMET Project No 416
Comments Results of this key comparison are older than 15 years and were thus placed in the KCDB Archives following the decision of the CCRI(II) at its 17th meeting in 2003 (see pages 37 and 38 of the CCRI Report of its 18th meeting in 2003) to gradually phase out old data to ensure that the KCDB maintains its currency.

For the same reason, this comparison was placed in the KCDB archives on 12 March 2024.
 
Pilot institute NPL
National Physical Laboratory
United Kingdom
Contact person M.J. Woods

+44 (0) 20 8943 6425
First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory
NPL

National Physical Laboratory, United Kingdom, EURAMET

BIPM

Bureau International des Poids et Mesures, BIPM - International Organization, N/A

CIEMAT

Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas, Spain, EURAMET

NRC

National Research Council, Canada, SIM

PTB

Physikalisch-Technische Bundesanstalt, Germany, EURAMET

Comparison
Comparison close
Results

EUROMET.RI(II)-K2.Np-237 was placed in the KCDB archives on 12 March 2024

 

BIPM.RI(II)-K1.Np-237 and EUROMET.RI(II)-K2.Np-237

MEASURAND : Equivalent activity of 237Np

  • Key comparison BIPM.RI(II)-K1.Np-237

 

Key comparison reference value: the SIR reference value for this radionuclide is xR = 74.85 MBq, with a standard uncertainty uR = 0.11 MBq (see section 4.1 of the Final Report).

 

 

The degree of equivalence of each laboratory 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. With n the number of laboratories, when each laboratory has contributed to the computation of xR.

 

 

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 in the Matrix of equivalence.

 

  • Linking EUROMET.RI(II)-K2.Np-237 to BIPM.RI(II)-K1.Np-237

 

The value xi is the equivalent activity for laboratory i participant in EUROMET.RI(II)-K2.Np-237 having been normalized using the SIR measurements of the BIPM, PTB, and the IRMM as linking laboratories.

 

 

The degree of equivalence of laboratory i participant in EUROMET.RI(II)-K2.Np-237 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, one participant in BIPM.RI(II)-K1.Np-237 and one in EUROMET.RI(II)-K2.Np-237, or both participants in EUROMET.RI(II)-K2.Np-237, is given by a pair of terms expressed in MBq:
Dij = Di - Dj and Uij, its expanded uncertainty (k = 2), approximated by
Uij = 2(ui2 + uj2 - 2ful2)1/2 with ul being the standard uncertainty of the link when each laboratory is from EUROMET and f is the correlation coefficient.

 

These statements make it possible to extend the BIPM.RI(II)-K1.Np-237 matrix of equivalence to all participants in EUROMET.RI(II)-K2.Np-237.

 

 

Comparison
Comparison close
Results

EUROMET.RI(II)-K2.Np-237 was placed in the KCDB archives on 12 March 2024

 

BIPM.RI(II)-K1.Np-237 and EUROMET.RI(II)-K2.Np-237

MEASURAND : Equivalent activity of 237Np

  • Key comparison BIPM.RI(II)-K1.Np-237

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
/ kBq
ui
/ kBq
Date of measurement
       
 BIPM 75440 790 12-06-1998
 PTB 74740 220 02-02-2006
 IRMM 74950 180 27-02-2007

 

 

 

  • Key comparison EUROMET.RI(II)-K2.Np-237

xi : result of measurement carried out at laboratory i converted to the equivalent activity through the linking laboratories BIPM, PTB and the IRMM
ui : combined standard uncertainty of xi

 

 Lab i xi
/ kBq
ui
/ kBq
Year of measurement
       
 LNE-LNHB 75210 230 1998
 CIEMAT 75510 380 1999
 NPL 74210 450 1998
 NRC 74060 820 1998