CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17

TEMPERATURE : 15 °C

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

Red diamonds: participants in CCQM-K19
Green triangles: participants in CCQM-K19.1 only

Blue circles: participants in APMP.QM-K19 only

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17

TEMPERATURE : 25 °C

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

Red diamonds: participants in CCQM-K19
Green triangles: participants in CCQM-K19.1 only

Blue circles: participants in APMP.QM-K19 only

Note: DNPLI = -0.2030 and UNPLI = 0.0686
 

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17

TEMPERATURE : 37 °C

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

Red diamonds: participants in CCQM-K19
Green triangles: participants in CCQM-K19.1 only

Blue circles: participants in APMP.QM-K19 only

Note: DNPLI = -0.2455 and UNPLI = 0.1144

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17

TEMPERATURE : 15 °C

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

Dark blue: participants in CCQM-K19
Green: participants in CCQM-K19.1 only

Blue: participants in APMP.QM-K19 only

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

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17

TEMPERATURE : 25 °C

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

Dark blue: participants in CCQM-K19
Green: participants in CCQM-K19.1 only

Blue: participants in APMP.QM-K19 only

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

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17

TEMPERATURE : 37 °C

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

Dark blue: participants in CCQM-K19
Green: participants in CCQM-K19.1 only

Blue: participants in APMP.QM-K19 only

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

Comparison
Comparison close
CC comparison
Linked comparison
CCQM-K19.1
Metrology area, Sub-field Chemistry and Biology, Electrochemistry
Description pH measurement of borate buffer solutions
Time of measurements 2010
Status Approved for equivalence
Final Reports of the comparisons
Measurand pH 9.2
Parameters Temperature: 15 °C, 25 °C and 37 °C
Transfer device Borate buffer solutions
Comparison type Key Comparison
Consultative Committee CCQM (Consultative Committee for Amount of Substance)
Conducted by CCQM (Consultative Committee for Amount of Substance)
Comments

Results published on 16 June 2011

CCQM-K19.1 and APMP.QM-K19 results are linked to those of CCQM-K19

pH of a borate buffer

Pilot institute PTB
Physikalisch-Technische Bundesanstalt
Germany
Contact person P. Spitzer

+49 (0) 531 592 3130
First Name Last Name
wwww@ww.www +356719836 Institute 1 Institute 1 Khmelnitskiy
Pilot laboratory
PTB

Physikalisch-Technische Bundesanstalt, Germany, EURAMET

DFM

Danish Fundamental Metrology A/S, Denmark, EURAMET

INMETRO

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

LNE

Laboratoire national de métrologie et d'essais, France, EURAMET

NIM

National Institute of Metrology, China, APMP

NIST

National Institute of Standards and Technology, United States, SIM

NMIJ AIST

National Metrology Institute of Japan, Japan, APMP

SMU

Slovensky Metrologicky Ustav, Slovakia, EURAMET

CCQM-K19, CCQM-K19.1 and AMPM.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 15 °C

  • Key comparison CCQM-K19

The key comparison reference value, xR, is computed as the median of all results except the NCM result, which is identified as an outlier and thus is not taken into account (see Annex B of the CCQM-K19 Final Report).
Its standard uncertainty, uR, is the standard uncertainty of the median.

xR = 9.3222 and 2uR = 0.0014

The degree of equivalence of each laboratory i 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), Ui = 2(ui2 + uR2)1/2.
The NCM degree of equivalence is not computed.
The degree of equivalence between two laboratories i and j is given by a pair of terms: Dij = Di - Dj = xi - xj and Uij, its expanded uncertainty (k = 2),
Uij = 2(ui2 + uj2)1/2.
No pair-wise degrees of equivalence are explicitely computed here.
  • Linking key comparison CCQM-K19.1 to key comparison CCQM-K19

The linkage of key comparison CCQM-K19.1 to key comparison CCQM-K19 is explained on page 15 of the CCQM-K19.1 Final Report. It relies on the common participation of NMIJ, PTB and SMU. Each of these laboratories demontrated consistent results and uncertainties in both comparisons.
The degrees of equivalence of participants in CCQM-K19.1 only, relative to the CCQM-K19 key comparison reference value, is given by two terms: Di and Ui, its expanded uncertainty (k = 2), computed according to equations 11 and 12 of the CCQM-K19.1 Final Report.

  • Linking key comparison APMP.QM-K19 to key comparison CCQM-K19

The results of the participants in APMP.QM-K19 are linked to those of CCQM-K19 through the results of the two linking laboratories, NMIJ and SMU, as explained in Section 8 of the APMP.QM-K19 Final Report.

CCQM-K19, CCQM-K19.1 and APMP.QM-K9

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 25 °C

  • Key comparison CCQM-K19

The key comparison reference value, xR, is computed as the median of all results.
Its standard uncertainty, uR, is the standard uncertainty of the median.

xR = 9.2300 and 2uR = 0.0013

The degree of equivalence of each laboratory i 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), Ui = 2(ui2 + uR2)1/2.
The degree of equivalence between two laboratories i and j is given by a pair of terms: Dij = Di - Dj = xi - xj and Uij, its expanded uncertainty (k = 2),
Uij = 2(ui2 + uj2)1/2.
No pair-wise degrees of equivalence are explicitely computed here.
  • Linking key comparison CCQM-K19.1 to key comparison CCQM-K19

The linkage of key comparison CCQM-K19.1 to key comparison CCQM-K19 is explained on page 15 of the CCQM-K19.1 Final Report. It relies on the common participation of NMIJ, PTB and SMU. Each of these laboratories demontrated consistent results and uncertainties in both comparisons.
The degrees of equivalence of participants in CCQM-K19.1 only, relative to the CCQM-K19 key comparison reference value, is given by two terms: Di and Ui, its expanded uncertainty (k = 2), computed according to equations 11 and 12 of the CCQM-K19.1 Final Report.

  • Linking key comparison APMP.QM-K19 to key comparison CCQM-K19

The results of the participants in APMP.QM-K19 are linked to those of CCQM-K19 through the results of the two linking laboratories, NMIJ and SMU, as explained in Section 8 of the APMP.QM-K19 Final Report.

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 37 °C

  • Key comparison CCQM-K19

The key comparison reference value, xR, is computed as the median of all results.
Its standard uncertainty, uR, is the standard uncertainty of the median.

xR = 9.1421 and 2uR = 0.0024

The degree of equivalence of each laboratory i 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), Ui = 2(ui2 + uR2)1/2.
The degree of equivalence between two laboratories i and j is given by a pair of terms: Dij = Di - Dj = xi - xj and Uij, its expanded uncertainty (k = 2),
Uij = 2(ui2 + uj2)1/2.
No pair-wise degrees of equivalence are explicitely computed here.
  • Linking key comparison CCQM-K19.1 to key comparison CCQM-K19

The linkage of key comparison CCQM-K19.1 to key comparison CCQM-K19 is explained on page 15 of the CCQM-K19.1 Final Report. It relies on the common participation of NMIJ, PTB and SMU. Each of these laboratories demontrated consistent results and uncertainties in both comparisons.
The degrees of equivalence of participants in CCQM-K19.1 only, relative to the CCQM-K19 key comparison reference value, is given by two terms: Di and Ui, its expanded uncertainty (k = 2), computed according to equations 11 and 12 of the CCQM-K19.1 Final Report.

  • Linking key comparison APMP.QM-K19 to key comparison CCQM-K19

The results of the participants in APMP.QM-K19 are linked to those of CCQM-K19 through the results of the two linking laboratories, NMIJ and SMU, as explained in Section 8 of the APMP.QM-K19 Final Report.

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

  • Key comparison CCQM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 15 °C

xi : result of measurement carried out by laboratory i
ULab i : expanded uncertainty (k = 2) of xi, ULab i = 2ui

 Lab i

xi ULab i Date of
measurement
       
 CENAM 9.3212 0.0148 Sep 05
 Radiometer A/S 9.3268 0.0019 Sep 05
 GUM 9.3266 0.0026 Oct 05
 KRISS 9.3247 0.0034 Sep 05
 NCM 9.2955 0.0045 Sep 05
 NMIJ 9.3224 0.0028 Sep 05
 NIST 9.3220 0.011 Sep 05
 OMH 9.3220 0.0054 Sep 05
 PTB 9.3214 0.0025 Aug - Sep 05
 SMU 9.3210 0.0025 Sep 05
 VNIIFTRI 9.3296 0.0040 Sep 05

  • Key comparison CCQM-K19.1

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 15 °C

xi1 : result of measurement carried out by laboratory i
ui1 : combined standard uncertainty (k = 1) of xi1

 Lab i

xi1 ui1 Date of
measurement
       
 INMETRO 9.3250 0.0039 2010
 NIM 9.3385 0.0016 2010
 PTB 9.3314 0.0011 2010
 DFM 9.3352 0.00085 2010
 LNE 9.3236 0.0025 2010
 NMIJ 9.3305 0.00119 2010
 SMU 9.3325 0.00110 2010
 NIST 9.3337 0.00069 2010
  • Key comparison APMP.QM-K19

MEASURAND : pH of an unknown borate buffer, pH ~ 9.2
TEMPERATURE : 15 °C

xi : result of measurement carried out by laboratory i
ui : combined standard uncertainty of xi

 Lab i

xi ui Date of
measurement
       
 NMIJ 9.2726 0.0012 2013
 NIMT 9.2905 0.0045 2013
 GL 9.280 0.0073 2013
 NML-SIRIM 9.2919 0.0035 2013
 VMI-STAMEQ 9.270 0.0065 2013
 SMU 9.2739 0.0014 2013
 LNE 9.2735 0.0014 2013
 NPLI - - -
 INDECOPI 9.274 0.002 2013
 INMETRO 9.2682 0.0010 2013
 CMI 9.2759 0.0011 2013
 BelGIM 9.297 0.0032 2013
 KazInMetr - - -

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

  • Key comparison CCQM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 25 °C

xi : result of measurement carried out by laboratory i
ULab i : expanded uncertainty (k = 2) of xi, ULab i = 2ui

 Lab i

xi ULab i Date of
measurement
       
 CENAM 9.2291 0.0063 Sep 05
 Radiometer A/S 9.2361 0.0017 Sep 05
 GUM 9.2269 0.0046 Oct 05
 KRISS 9.2343 0.0030 Sep 05
 NCM 9.2295 0.0044 Sep 05
 NMIJ 9.2303 0.0030 Sep 05
 NIST 9.2300 0.011 Sep 05
 OMH 9.2230 0.0054 Sep 05
 PTB 9.2300 0.0025 Aug - Sep 05
 SMU 9.2289 0.0023 Sep 05
 VNIIFTRI 9.2372 0.0040 Sep 05

  • Key comparison CCQM-K19.1

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 25 °C

xi1 : result of measurement carried out by laboratory i
ui1 : combined standard uncertainty (k = 1) of xi1

 Lab i

xi1 ui1 Date of
measurement
       
 INMETRO 9.2367 0.0022 2010
 NIM 9.2465 0.0017 2010
 PTB 9.2399 0.0011 2010
 DFM 9.2432 0.00094 2010
 LNE 9.2321 0.0020 2010
 NMIJ 9.2379 0.00117 2010
 SMU 9.2390 0.00109 2010
 NIST 9.2409 0.00056 2010
  • Key comparison APMP.QM-K19

MEASURAND : pH of an unknown borate buffer, pH ~ 9.2
TEMPERATURE : 25 °C

xi : result of measurement carried out by laboratory i
ui : combined standard uncertainty of xi

 Lab i

xi ui Date of
measurement
       
 NMIJ 9.1802 0.0011 2013
 NIMT 9.2110 0.0034 2013
 GL 9.188 0.0061 2013
 NML-SIRIM 9.2030 0.0035 2013
 VMI-STAMEQ 9.208 0.0053 2013
 SMU 9.1799 0.0010 2013
 LNE 9.1804 0.0014 2013
 NPLI 8.9775 0.0343 2013
 INDECOPI 9.182 0.002 2013
 INMETRO 9.1759 0.0011 2013
 CMI 9.1787 0.0018 2013
 BelGIM 9.1977 0.0022 2013
 KazInMetr 9.1814 0.0015 2013

CCQM-K19, CCQM-K19.1 and APMP.QM-K19

  • Key comparison CCQM-K19

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 37 °C

xi : result of measurement carried out by laboratory i
ULab i : expanded uncertainty (k = 2) of xi, ULab i = 2ui

 Lab i

xi ULab i Date of
measurement
       
 CENAM 9.1401 0.0034 Sep 05
 Radiometer A/S 9.1485 0.0017 Sep 05
 GUM 9.1429 0.0054 Oct 05
 KRISS 9.1471 0.0031 Sep 05
 NCM 9.1400 0.0045 Sep 05
 NMIJ 9.1426 0.0026 Sep 05
 NIST 9.1420 0.011 Sep 05
 OMH 9.1370 0.0040 Sep 05
 PTB 9.1421 0.0025 Aug - Sep 05
 SMU 9.1415 0.0023 Sep 05
 VNIIFTRI 9.1495 0.0040 Sep 05

 

  • Key comparison CCQM-K19.1

MEASURAND : Acidity function at zero chloride molality of an unknown borate buffer, pH ~ 9.17
TEMPERATURE : 37 °C

xi1 : result of measurement carried out by laboratory i
ui1 : combined standard uncertainty (k = 1) of xi1

 Lab i

xi1 ui1 Date of
measurement
       
 INMETRO 9.1541 0.0041 2010
 NIM 9.1592 0.0016 2010
 PTB 9.1522 0.0011 2010
 DFM 9.1550 0.00098 2010
 LNE 9.1441 0.0024 2010
 NMIJ 9.1503 0.00117 2010
 SMU 9.1505 0.00109 2010
 NIST 9.1516 0.00078 2010

 

  • Key comparison APMP.QM-K19

MEASURAND : pH of an unknown borate buffer, pH ~ 9.2
TEMPERATURE : 37 °C

xi : result of measurement carried out by laboratory i
ui : combined standard uncertainty of xi

 Lab i

xi ui Date of
measurement
       
 NMIJ 9.0912 0.0011 2013
 NIMT 9.1156 0.0041 2013
 GL 9.100 0.0062 2013
 NML-SIRIM 9.1125 0.0035 2013
 VMI-STAMEQ 9.131 0.0052 2013
 SMU 9.0898 0.0018 2013
 LNE 9.0907 0.0014 2013
 NPLI 8.845 0.0572 2013
 INDECOPI 9.093 0.002 2013
 INMETRO 9.0853 0.0017 2013
 CMI 9.0875 0.0011 2013
 BelGIM 9.1073 0.0031 2013
 KazInMetr - - -