Comparison
Comparison close
Results

CCT-K7.2021

 

MEASURAND   Temperature of the triple point of water

NOMINAL VALUE 273.16 K

 

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

Lab i
Di / µK
Participating institutes
Comparison
Comparison close
Results

CCT-K7.2021

 

MEASURAND   Temperature of the triple point of water

NOMINAL VALUE 273.16 K

 

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

LABi Di Uneg,i Upos,i
µK
µK
µK
CEM 47.0 78.1
INMETRO -39.9 71.3
IPQ 7.0 158.3
KRISS -4.7 63.2
LNE-LCM/Cnam 1.2 97.6
MSL 14.1 25.3
NIM -1.1 63.0
NMIA -21.0 46.2
NMIJ 22.4 60.6
NMISA -1.5 120.9
NPL 10.8 47.6
NRC -6.9 36.8
PTB 6.9 50.4
UME -64.1 104.7
VSL -44.7 56.3
Participating institutes
CCT-K7.2021
Comparison
Comparison close
CC comparison
Linked comparison
CCT-K7.2021
Metrology area, Sub-field Thermometry, Fixed Point Cells
Description Comparison of Water Triple Point Cells
 
Time of measurements 2021 - 2022
Status Approved for equivalence
Final Reports of the comparisons
Measurand Triple point of water
273.16 K
Transfer device Triple point of water cell
Comparison type Key Comparison
Consultative Committee CCT (Consultative Committee for Thermometry)
Conducted by CCT (Consultative Committee for Thermometry)
Pilot institute NRC
National Research Council
Canada
Contact person Andrea Peruzzi

First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory
NRC

National Research Council, Canada, SIM

CEM

Centro Español de Metrologia, Spain, EURAMET

INMETRO

Instituto Nacional de Metrologia, Qualidade e Tecnologia, Brazil, SIM

IPQ

Instituto Portugues da Qualidade, Portugal, EURAMET

KRISS

Korea Research Institute of Standards and Science, Korea, Republic of, APMP

LNE-LCM/Cnam

Conservatoire National des Arts et Métiers/Laboratoire Commun de Métrologie, France, EURAMET

MSL

Measurement Standards Laboratory, New Zealand, APMP

NIM

National Institute of Metrology, China, APMP

NMIA

National Measurement Institute, Australia, Australia, APMP

NMIJ AIST

National Metrology Institute of Japan, Japan, APMP

NMISA

National Metrology Institute of South Africa, South Africa, AFRIMETS

NPL

National Physical Laboratory, United Kingdom, EURAMET

PTB

Physikalisch-Technische Bundesanstalt, Germany, EURAMET

UME

TÜBITAK Ulusal Metroloji Enstitüsü, Türkiye, EURAMET

VSL

VSL, Netherlands, EURAMET

Comparison
Comparison close
Results

CCT-K7.2021

MEASURAND   Temperature of the triple point of water

NOMINAL VALUE 273.16 K

 

The key comparison reference value, xR, and its combined uncertainty, uR, are calculated using the adaptive weighted average (DerSimonian-Laird procedure, see [1]) of the NIST Decision Tree [2]. For the particular data set of this key comparison, the result of the adaptive weighted average is identical to that of the conventional weighted average.

xR = 4.7 µK

uR = 7.2 µK

[1] R. DerSimonian, N. Laird (1986) "Meta-analysis in clinical trials," Controlled Clinical Trials 7(3):177-188.

[2] A. Possolo, A. Koepke, D. Newton, M.r. Winchester, "Decision Tree for Key Comparisons," 2021 J Res Natl Inst Stan 126:126007

 

The degree of equivalence of laboratory i with respect to the key comparison reference value is given by a pair of terms:
Di = (xi - xR) and its expanded uncertainty Ui (k = 2), both expressed in µK.
The expanded uncertainties of the Di take into account the correlations between the measured values and the key comparison reference value.

Comparison
Comparison close
Results

CCT-K7.2021

MEASURAND         Temperature of the triple point of water

NOMINAL VALUE       273.16 K

PILOT LABORATORY  NRC

xi : temperature difference between the national reference of laboratory i and the pilot's reference, xi = TLabi - TPilot Ref, where T is the temperature

ui : standard uncertainty of xi 

See also section 5.1 of the Final report for the calculation of xi and ui

  Labi xi ui
    µK µK
  CEM 51.7 40.2
  INMETRO -35.1 37.6
  IPQ 11.7 82.3
  KRISS 0.0 32.4
  LNE-LCM/Cnam 5.9 50.7
  MSL 18.8 13.2
  NIM 3.6 33.1
  NMIA -16.2 24.4
  NMIJ 27.1 31.9
  NMISA 3.2 62.2
  NPL 15.5 24.9
  NRC -2.2 19.8
  PTB 11.6 26.7
  UME -59.3 53.8
  VSL -39.9 29.6