CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
Degrees of equivalence represented by Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence.
Enlarged graph
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
Degrees of equivalence represented by Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence.
Enlarged graph
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
Degrees of equivalence represented by Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence.
Enlarged graph
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
Degrees of equivalence represented by Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence.
| LABi | Di | Uneg,i | Upos,i | |
|---|---|---|---|---|
dimensionless |
dimensionless |
dimensionless |
||
| BIM | -0.001 | 0.004 | ||
| CENAM | 0.000 | 0.004 | ||
| CMI | 0.002 | 0.003 | ||
| DFM | 0.000 | 0.002 | ||
| GUM | -0.009 | 0.003 | ||
| INDECOPI | -0.002 | 0.004 | ||
| INMETRO | 0.002 | 0.003 | ||
| MKEH | 0.000 | 0.006 | ||
| NIMT | -0.055 | 0.039 | ||
| NIST | 0.002 | 0.002 | ||
| NMIJ | 0.000 | 0.003 | ||
| PTB | -0.001 | 0.003 | ||
| SMU | -0.001 | 0.004 | ||
| UME | -0.022 | 0.002 | ||
| SE "Ukrmetrteststandard" | 0.012 | 0.006 | ||
| VNIIFTRI | -0.004 | 0.004 | ||
| KRISS | -0.001 | 0.004 |
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
Degrees of equivalence represented by Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence.
| LABi | Di | Uneg,i | Upos,i | |
|---|---|---|---|---|
dimensionless |
dimensionless |
dimensionless |
||
| BIM | -0.002 | 0.004 | ||
| CENAM | -0.001 | 0.006 | ||
| CMI | 0.004 | 0.003 | ||
| DFM | -0.001 | 0.002 | ||
| GUM | -0.007 | 0.003 | ||
| IBMETRO | 0.003 | 0.010 | ||
| INDECOPI | -0.004 | 0.004 | ||
| INMETRO | 0.001 | 0.003 | ||
| LATU | -0.004 | 0.010 | ||
| MKEH | -0.002 | 0.007 | ||
| NIMT | -0.057 | 0.029 | ||
| NIST | 0.001 | 0.002 | ||
| NMIJ | -0.001 | 0.002 | ||
| PTB | -0.001 | 0.003 | ||
| SMU | -0.003 | 0.003 | ||
| UME | 0.005 | 0.002 | ||
| SE "Ukrmetrteststandard" | 0.005 | 0.004 | ||
| VNIIFTRI | -0.006 | 0.004 | ||
| KRISS | -0.002 | 0.004 |
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
Degrees of equivalence represented by Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence.
| LABi | Di | Uneg,i | Upos,i | |
|---|---|---|---|---|
dimensionless |
dimensionless |
dimensionless |
||
| BIM | -0.006 | 0.004 | ||
| CENAM | -0.004 | 0.005 | ||
| CMI | -0.006 | 0.004 | ||
| DFM | 0.001 | 0.002 | ||
| GUM | -0.010 | 0.004 | ||
| INDECOPI | 0.000 | 0.004 | ||
| INMETRO | -0.001 | 0.005 | ||
| LATU | 0.002 | 0.010 | ||
| MKEH | -0.004 | 0.007 | ||
| NIMT | -0.053 | 0.022 | ||
| NIST | 0.002 | 0.002 | ||
| NMIJ | 0.001 | 0.003 | ||
| PTB | 0.001 | 0.003 | ||
| SMU | -0.001 | 0.004 | ||
| UME | -0.020 | 0.003 | ||
| SE "Ukrmetrteststandard" | 0.004 | 0.005 | ||
| VNIIFTRI | -0.004 | 0.005 | ||
| KRISS | 0.001 | 0.004 |
| Metrology area, Sub-field | Chemistry and Biology, Electrochemistry |
| Description | pH of phosphate buffer solution |
| Time of measurements | 2026 - 2027 |
| Status | Planned |
| References | |
| Measurand | pH from 6.80 to 7.00 |
| Parameters | Measurement temperature: 25 °C (optionally 15 °C and 37 °C) |
| Transfer device | Dedicated samples |
| Comparison type | Key Comparison |
| Consultative Committee | CCQM (Consultative Committee for Amount of Substance) |
| Conducted by | COOMET (Euro-Asian Cooperation of National Metrological Institutions) |
| RMO Internal Identifier | COOMET 630/RU/25 |
| Comments | The measurement method (primary method or secondary method using a differential potentiometric cell, or working method using a glass electrode pH-meter) is the choice of the each participant-laboratory based on its measurement capabilities. It is possible to use several methods, but only the results obtained by the primary method per temperature will be considered when calculating the key comparison reference value. |
| Pilot institute |
VNIIFTRI
Institute of Physical Technical and Radiotechnical Measurements, Rosstandart Russian Federation |
| Contact person | Narine Oganyan +79017227886 |
| Additional |
| Pilot laboratory | |
|---|---|
| VNIIFTRI |
Institute of Physical Technical and Radiotechnical Measurements, Rosstandart, Russian Federation, COOMET |
| RCAM-Rostest |
Research Center for Applied Metrology - Rostest, Russian Federation, COOMET |
This page proposes print-out on A4 paper (portrait) of the comparison details (best printed out using a black and white printer).
Please, select items to be printed out, then click on "OK" :
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
The key comparison reference value xR and its associated standard uncertainty uR is obtained by calculating the weigthted mean including the institutes using primary standards for which the results passed a previously defined consistancy filter.
xR = 7.5561 uR = 0.0009
The degree of equivalence of laboratory i relative to the key comparison reference value xR is given by a pair of terms:
Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence where Ui = 2 ( (1 − 2wi) ui2 + uR2)1/2 where wi represents the weight of laboratory i.
Linking CCQM-K99.1 to CCQM-K99
PTB provides the link between the key comparison CCQM-K99 and CCQM-K99.1, having participated in both comparisons. The linking process is described in Section 9 of the CCQM-K99.1 Final report.
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
The key comparison reference value xR and its associated standard uncertainty uR is obtained by calculating the weigthted mean including the institutes using primary standards for which the results passed a previously defined consistancy filter.
xR = 7.5246 uR = 0.0008
The degree of equivalence of laboratory i relative to the key comparison reference value xR is given by a pair of terms:
Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence where Ui = 2 ( (1 − 2wi) ui2 + uR2)1/2 where wi represents the weight of laboratory i.
Linking CCQM-K99.1 to CCQM-K99
PTB provides the link between the key comparison CCQM-K99 and CCQM-K99.1, having participated in both comparisons. The linking process is described in Section 9 of the CCQM-K99.1 Final report.
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
The key comparison reference value xR and its associated standard uncertainty uR is obtained by calculating the weigthted mean including the institutes using primary standards for which the results passed a previously defined consistancy filter.
xR = 7.5013 uR = 0.0009
The degree of equivalence of laboratory i relative to the key comparison reference value xR is given by a pair of terms:
Di = (xi - xR) and its expanded uncertainty Ui at a 95 % level of confidence where Ui = 2 ( (1 − 2wi) ui2 + uR2)1/2 where wi represents the weight of laboratory i.
Linking CCQM-K99.1 to CCQM-K99
PTB provides the link between the key comparison CCQM-K99 and CCQM-K99.1, having participated in both comparisons. The linking process is described in Section 9 of the CCQM-K99.1 Final report.
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
xi measurement value submitted by institute i, Labi
ui combined standard uncertainty of xi
CCQM-K99
| Labi | xi | ui | |
| BIM | 7.5553 | 0.0020 | |
| CENAM | 7.5561 | 0.0016 | |
| CMI | 7.5585 | 0.0013 | |
| DFM | 7.5563 | 0.0008 | |
| GUM | 7.5474 | 0.0013 | |
| INDECOPI | 7.5542 | 0.0020 | |
| INMETRO | 7.5582 | 0.0013 | |
| MKEH | 7.5558 | 0.0030 | |
| NIMT | 7.5006 | 0.0197 | |
| NIST | 7.5578 | 0.0008 | |
| NMIJ | 7.5561 | 0.0010 | |
| PTB | 7.5553 | 0.0011 | |
| SMU | 7.5554 | 0.0016 | |
| UME | 7.5337 | 0.0010 | |
| SE "Ukrmetrteststandard" | 7.5683 | 0.0028 | |
| VNIIFTRI | 7.5520 | 0.0020 |
CCQM-K99.1
| Labi | xi | ui | |
| KRISS | 7.3265 | 0.0013 |
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
xi measurement value submitted by institute i, Labi
ui combined standard uncertainty of xi
CCQM-K99
| Labi | xi | ui | |
| BIM | 7.5228 | 0.0020 | |
| CENAM | 7.5239 | 0.0027 | |
| CMI | 7.5287 | 0.0013 | |
| DFM | 7.5232 | 0.0008 | |
| GUM | 7.5178 | 0.0014 | |
| IBMETRO | 7.5276 | 0.0050 | |
| INDECOPI | 7.5209 | 0.0020 | |
| INMETRO | 7.5255 | 0.0013 | |
| LATU | 7.5206 | 0.0050 | |
| MKEH | 7.5226 | 0.0033 | |
| NIMT | 7.4679 | 0.0143 | |
| NIST | 7.5255 | 0.0008 | |
| NMIJ | 7.5236 | 0.0010 | |
| PTB | 7.5235 | 0.0011 | |
| SMU | 7.5220 | 0.0015 | |
| UME | 7.5291 | 0.0010 | |
| SE "Ukrmetrteststandard" | 7.5295 | 0.0021 | |
| VNIIFTRI | 7.5190 | 0.0021 |
CCQM-K99.1
| Labi | xi | ui | |
| KRISS | 7.2936 | 0.0014 |
CCQM-K99 and CCQM-K99.1
MEASURAND pH value of an unknown phosphate buffer
NOMINAL VALUE pH = 7.5
xi measurement value submitted by institute i, Labi
ui combined standard uncertainty of xi
CCQM-K99
| Labi | xi | ui | |
| BIM | 7.4951 | 0.0020 | |
| CENAM | 7.4973 | 0.0024 | |
| CMI | 7.4954 | 0.0020 | |
| DFM | 7.5021 | 0.0008 | |
| GUM | 7.4917 | 0.0016 | |
| INDECOPI | 7.5014 | 0.0020 | |
| INMETRO | 7.5006 | 0.0022 | |
| LATU | 7.5029 | 0.0050 | |
| MKEH | 7.4973 | 0.0034 | |
| NIMT | 7.4482 | 0.0110 | |
| NIST | 7.5036 | 0.0008 | |
| NMIJ | 7.5025 | 0.0010 | |
| PTB | 7.5027 | 0.0011 | |
| SMU | 7.5005 | 0.0019 | |
| UME | 7.4812 | 0.0010 | |
| SE "Ukrmetrteststandard" | 7.5055 | 0.0021 | |
| VNIIFTRI | 7.4970 | 0.0023 |
CCQM-K99.1
| Labi | xi | ui | |
| KRISS | 7.2725 | 0.0014 |
