Calibrations Scope

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Electrical SCOPE ISO 17025-2005

 

    The Least uncertainties of measurement for Electrical quantity/measurement as per the ISO GUM:-
1.0 INDICATING AND RECORDING INSTRUMENTS  
               
  MEASUREMENT FUNCTION   WITH LEAST UNCERTAINTIES OF MEASUREMENT       
               
1.0.1 DC VOLTMETER   Tol(%) Floor      
   0 TO ± 330.00 mV   0.0047 2E-06      
  0 TO ± 3.3 V   0.0039 4E-06      
  0 TO ± 33.0 V   0.0039 4E-05      
  0 TO ± 330.0 V   0.0043 4E-04      
  0 TO ± 1020 V   0.0043 1E-03      
               
               
1.0.2 DC CURRENT    Tol(%) Floor      
   0 TO ± 330.00 µA   0.0116 2E-08      
  0 TO ± 3.3 mA   0.0101 4E-08      
  0 TO ± 33.0 mA   0.0078 2E-07      
  0 TO ± 330.0 mA   0.0078 2E-06      
  0 TO ± 3.0 A   0.0295 3E-05      
  0 TO ± 10.0 A   0.0465 4E-04      
  0 TO ± 20.5 A   0.0775 6E-04      
               
1.0.3 RESISTANCE   Tol(%) Floor      
  0 TO 11 Ohm   0.0093 8E-04      
  11 TO 33 Ohm   0.0093 1E-03      
  33 TO 110 Ohm   0.0070 1E-03      
  110 TO 330 Ohm   0.0070 2E-03      
  330 TO 1.1 kOhm   0.0070 2E-03      
  1.1 TO 3.3 kOhm   0.0070 2E-02      
  3.3 TO 11 kOhm   0.0070 2E-02      
  11 TO 33 kOhm   0.0070 2E-01      
  33 TO 110 kOhm   0.0085 2E-01      
  110  TO 330 kOhm   0.0093 2E+00      
  330 TO 1.1 MOhm   0.0116 2E+00      
  1.1 TO 3.3 MOhm   0.0116 2E+01      
  3.3 TO 11 MOhm   0.0465 4E+01      
  11TO 33 MOhm   0.0775 2E+03      
  33 TO 110 MOhm   0.3876 2E+03      
  110 TO 330 MOhm   0.3876 8E+04      
  330 TO 1.1 GOhm   1.1628 4E+05      
               
               
1.0.4 AC VOLTAGE FREQUENCY Tol(%) Floor      
  1.0 to 33 mV 0.01 Hz to 10 Hz 3.876 1E-04      
    10 Hz to 45 Hz 0.116 2E-05      
    45 Hz to 10 kHz 0.078 2E-05      
    10 to 20 kHz 0.116 2E-05      
    20 to 50 kHz 0.155 2E-05      
    50 to 100 kHz 0.271 3E-05      
    100 to 500 kHz 0.775 5E-05      
               
  33 to 330 mV 0.01 Hz to 10 Hz 3.876 1E-03      
    10 Hz to 45 Hz 0.039 2E-05      
    45 Hz to 10 kHz 0.023 2E-05      
    10 to 20 kHz 0.054 2E-05      
    20 to 50 kHz 0.078 3E-05      
    50 to 100 kHz 0.178 1E-04      
    100 to 500 kHz 0.388 3E-04      
               
  330 to 3.3 V 0.01 Hz to 10 Hz 3.876 1E-02      
    10 Hz to 45 Hz 0.039 5E-05      
    45 Hz to 10 kHz 0.023 5E-05      
    10 to 20 kHz 0.054 5E-05      
    20 to 50 kHz 0.078 5E-05      
    50 to 100 kHz 0.178 2E-04      
    100 to 500 kHz 0.388 7E-04      
               
  3.3  to 33.0 V 0.01 Hz to 10 Hz 3.876 1E-01      
    10 Hz to 45 Hz 0.039 6E-04      
    45 Hz to 10 kHz 0.023 5E-04      
    10 to 20 kHz 0.054 5E-04      
    20 to 50 kHz 0.078 5E-04      
    50 to 100 kHz 0.178 2E-03      
               
  33.0  to 330.0 V 45 Hz to 1 kHz 0.039 2E-03      
    1 to 10 kHz 0.062 7E-03      
    10 to 20 kHz 0.070 7E-03      
    20 to 50 kHz 0.093 7E-03      
    50 to 100 kHz 0.186 6E-02      
               
  330.0  to 1020.0 V 45 Hz to 1 kHz 0.039 2E-02      
    1 to 5 kHz 0.062 2E-02      
    5 to 10 kHz 0.070 2E-02      
               
               
1.0.5 AC CURRENT FREQUENCY Tol(%) Floor      
               
  29 to 330 µA 10 to 20 Hz 0.155 8E-08      
    20 to 45 Hz 0.116 8E-08      
    45 Hz to 1 kHz 0.097 8E-08      
    1 to 5 kHz 0.233 1E-07      
    5 to 10 kHz 0.620 2E-07      
    10 to 30 kHz 1.240 3E-07      
               
  330 to 3.3 mA 10 to 20 Hz 0.155 1E-07      
    20 to 45 Hz 0.097 1E-07      
    45 Hz to 1 kHz 0.078 1E-07      
    1 to 5 kHz 0.155 2E-07      
    5 to 10 kHz 0.388 2E-07      
    10 to 30 kHz 0.775 5E-07      
               
  3.3 to 33 mA 10 to 20 Hz 0.140 2E-06      
    20 to 45 Hz 0.070 2E-06      
    45 Hz to 1 kHz 0.031 2E-06      
    1 to 5 kHz 0.062 2E-06      
    5 to 10 kHz 0.155 2E-06      
    10 to 30 kHz 0.310 3E-06      
               
  33 to 330 mA 10 to 20 Hz 0.140 2E-05      
    20 to 45 Hz 0.070 2E-05      
    45 Hz to 1 kHz 0.031 2E-05      
    1 to 5 kHz 0.078 4E-05      
    5 to 10 kHz 0.155 8E-05      
    10 to 30 kHz 0.310 2E-04      
               
  330 mA to 1.1 A 10 to 45 Hz 0.140 8E-05      
    45 Hz to 1 kHz 0.039 8E-05      
    1 to 5 kHz 0.465 8E-04      
    5 to 10 kHz 1.938 4E-03      
               
  1.1 A to 3.0 A 10 to 45 Hz 0.140 8E-05      
    45 Hz to 1 kHz 0.047 8E-05      
    1 to 5 kHz 0.465 8E-04      
    5 to 10 kHz 1.938 4E-03      
               
  3.0 A to 11 A 45 Hz to 100 Hz 0.047 2E-03      
    100 Hz to 1 kHz 0.078 2E-03      
    1 to 5 kHz 2.326 2E-03      
               
  11 A to 20.5 A 45 Hz to 100 Hz 0.093 4E-03      
    100 Hz to 1 kHz 0.116 4E-03      
    1 to 5 kHz 2.326 4E-03      
               
               
1.0.6 CAPACITANCE   Tol(%) Floor      
               
  220 pF to 400 pF   0.388 8E-12      
  0.4 to 1.1 nF   0.388 8E-12      
  1.1 nF to 3.3 nF   0.388 8E-12      
  3.3 nF to 11 nF   0.194 8E-12      
  11 to 33 nF   0.194 8E-11      
  33 to 110 nF   0.194 8E-11      
  110 to 330 nF   0.194 2E-10      
  330 to 1.1 µF   0.194 8E-10      
  1.1 to 3.3  µF   0.194 2E-09      
  3.3 to 11  µF   0.194 8E-09      
  11 to 33 µF   0.310 2E-08      
  33 to 110 µF   0.349 8E-08      
  110 to 330  µF   0.349 2E-07      
  330  µF to 1.1 mF   0.349 8E-07      
  1.1 to 3.3 mF   0.349 2E-06      
  3.3 to 11 mF   0.349 8E-06      
  11 to 33 mF   0.581 2E-05      
  33 to 110 mF   0.853 8E-05      
               
1.0.7 FREQUENCY   Tol(%) Floor      
               
  0.01 to 119.99 Hz   0.002 7.8E-04      
  120 to 1200 Hz   7.8E-04      
  1.2 to 12 kHz   7.8E-04      
  12 to 120 kHz   1.2E-02      
  120 to 1200 kHz   1.2E-02      
  1.2 to 2 MHz   1.2E-02      
               
1.0.8 DC POWER    % of Watts Output        
  33 mV to 1020 V 3.3 to 329.99 mA 0.05        
    0.33 to 11 A 0.11        
    11 to 20 A 0.2        
               
               
1.0.9 AC Power    % of Watts Output        
  33 mV to 1020 V 3.3 to 329.99 mA 0.31        
  45 Hz to 65 Hz 0.33 to 11 A 0.27        
    11 to 20 A 0.27        
               
               
1.0.10 Phase Angle   ∆Φ degrees        
  33 mV to 1020 V 10 to 65 Hz 0.2        
    65 to 500 Hz 0.8        
    500 to 1kHz 1.6        
    1 kHz to 5 kHz 5        
    5 kHz to 10 kHz 9        
               
1.1 Graphic Recording & Digital storage Recorders            
  With least uncertainties as per 1.0            
               
1.2 Calibrators and Standards  
  MEASUREMENT FUNCTION   WITH LEAST UNCERTAINTIES OF MEASUREMENT         
1.2.1 DC VOLTAGE            
  0.1 V   ±1.04 µV        
  1 V   ±6.00 µV        
  10 V   ±50.0 µV        
  100 V   ±0.8 mV        
  1000 V   ±8.0 mV        
               
1.2.2 Ohms            
  10    ±0.25 mΩ        
  100    ±2.10 mΩ        
  1 k   ±0.015 Ω        
  10 k   ±0.15 Ω        
  100 k   ±1.5 Ω        
  1 M   ±24.0 Ω        
  10 M   ±0.74 kΩ        
  100 M   ±0.06 MΩ        
               
1.2.3 DC CURRENT            
  100 µA   ±2.0 nA        
  1 mA   ±13.0 nA        
  10 mA   ±0.13 µA        
  100 mA   ±1.8 µA        
  1 A   ±0.03 mA        
               
1.2.4 AC CURRENT FREQUENCY          
  100 µA 1 kHz ±0.02 µA        
  1 mA 1 kHz ±0.20 µA        
  10 mA 1 kHz ±2.0 µA        
  100 mA 1 kHz ±20.0 µA        
  1 A 1 kHz ±0.30 mA        
               
1.2.5 AC VOLTAGE FREQUENCY          
  0.01 V 1 kHz ±5.0 µV        
  0.01 V 20 kHz ±5.0 µV        
  0.01 V 100 kHz ±8.0 µV        
  0.01 V 300 kHz ±16.0 µV        
  0.01 V 1 MHz ±0.03 mV        
  0.01 V 4 MHz ±3.10 mV        
  0.1 V 1 kHz ±0.03 mV        
  0.1 V 20 kHz ±0.03 mV        
  0.1 V 100 kHz ±0.06 mV        
  0.1 V 300 kHz ±0.10 mV        
  0.1 V 1 MHz ±0.3 mV        
  0.1 V 4 MHz ±0.41 mV        
  0.1 V 8 MHz ±0.41 mV        
  0.1 V 10 MHz ±0.47 mV        
  1 V 1 kHz ±0.3 mV        
  1 V 20 kHz ±0.3 mV        
  1 V 50 kHz ±0.3 mV        
  1 V 100 kHz ±0.2 mV        
  1 V 300 kHz ±0.5 mV        
  1 V 500 kHz ±1.1 mV        
  1 V 1 MHz ±1.9 mV        
  1 V 4 MHz ±4.1 mV        
  1 V 8 MHz ±4.1 mV        
  1 V 10 MHz ±4.7 mV        
  10 V 10 Hz to 50 kHz ±3.0 mV        
  10 V 100 kHz ±1.0 mV        
  10 V 300 kHz ±3.0 mV        
  10 V 500 kHz ±11.0 mV        
  10 V 1 MHz ±17.0 mV        
  10 V 2 MHz ±0.127 V        
  10 V 4 MHz ±0.127 V        
  10 V 8 MHz ±0.128 V        
  10 V 10 MHz ±0.46 V        
  100 V 1 kHz ±30.0 mV        
  100 V 20 kHz ±30.0 mV        
  100 V 50 kHz ±30.0 mV        
  100 V 100 kHz ±20.0 mV        
  1000 V 1 kHz ±0.1 V        
               
1.2.6 FREQUENCY            
  1 Hz   ±5 x 10-6        
  10 MHz   ±50 x 10-8        
               
1.2.7 CAPACITANCE            
  ≤ 100 µF   ±0.2%        
  100 µF   ±1%        

SCOPE 17025

INDEX CLASS SUBCLASS CAPABILITY / UNCERTAINTY Procedure #’s
2.1 TEMPERATURE Radiation pyrometers calibration of infrared thermometers,
with a spectral response range of 6.5 to 18µm, and a preset emissivity of 0.95,
with least uncertainty of measurement of –  ±1.8°C from 0°C to 300°C
HKC030
2.2 TEMPERATURE Digital temperature indicator systems with least uncertainties of measurement of –
using thermocouple sensor , ±0.23°C from -50°C to 250°C,
using metallic resistance sensor, ±0.16°C from -50°C to 250°C,
HKC063
2.3 TEMPERATURE Ancillary temperature measuring instruments – Indicators, recorders and controllers with least uncertainties of measurement of –
for thermocouple temperature indicators,
±0.3°C from -100°C to 1000°C,
for metallic resistance thermometer indicators,
±0.06°C from -200°C to 260°C,
±0.1°C from 260°C to 630°C,
±0.2°C from 630°C to 800°C,
HKC001, HKC001A
2.4 TEMPERATURE Dry block calibrators with least uncertainty of measurement of –
±0.2°C from -50°C to 250°C
HKC063
2.5 TEMPERATURE Calibration of humidity measuring devices with least uncertainty of measurement of –
±3% RH from 10% to 90% RH
TBD
         
3.1 DIMENSIONAL Plain plug gauges with least uncertainties of measurement of –
±0.003mm from 0mm to 25mm,
±0.03mm from 25mm to 300mm,
HKC012, HKC034,
3.2 DIMENSIONAL External micrometers with least uncertainties of measurement of –
±0.0008mm from 0mm to 25mm,
±0.0012mm from 25mm to 75mm,
±0.0016mm from 75mm to 100mm
±0.006mm from 100mm to 250mm
HKC007,HKC008
3.3 DIMENSIONAL Electronic indicators, dial gauges and test indicators with least uncertainty of measurement of –
±0.0008mm from 0mm to 25mm
HKC007,HKC008
3.4 DIMENSIONAL Electronic and vernier callipers with least uncertainties of measurement of –
±0.0008mm from 0mm to 25mm,
±0.0012mm from 25mm to 75mm,
±0.0016mm from 75mm to 100mm
±0.006mm from 100mm to 250mm
HKC007,HKC008
3.5 DIMENSIONAL Feeler gauges with least uncertainty of measurement of –
±0.003mm from 0mm to 25mm
HKC034,
3.6 DIMENSIONAL Gauge blocks and accessories with least uncertainties of measurement of –
±0.003mm from 0mm to 25mm,
±0.03mm from 25mm to 300mm,
HKC012, HKC034,
3.7 DIMENSIONAL Length bars and accessories with least uncertainties of measurement of –
±0.003mm from 0mm to 25mm,
±0.03mm from 25mm to 300mm,
HKC012, HKC034,
3.8 DIMENSIONAL Precision graticules with least uncertainty of measurement of –
±(3 µm + 3L/1000), L: mm, from 0mm to 150mm
STANDARD SCALE
3.9 DIMENSIONAL Precision linear scales with least uncertainty of measurement of –
for transparent linear scales,
±(3 µm + 3L/1000), L: mm, from 0mm to 150mm
STANDARD SCALE
         
4.1 TORQUE Torque wrenches with least uncertainties of measurement of –
±0.5% from 0N·m to 2N·m,
±0.4% from 2N·m to 40N·m,
±0.2% from 40N·m to 400N·m,
±0.2% from 400N·m to 1500N·m,
HKC035, HKC035A, HKC037, HKC077, HKC077A
         
5.1 PRESSURE Pressure gauges with least uncertainties of measurement of –
±0.02 kPa from 0 kPa to 200 kPa
±1.2 kPa from 200 kPa to 10000 kPa,
±5 kPa from 10000 kPa to 60000 kPa,
±120 kPa from 60000 kPa to 100000 kPa
HKC038, HKC039, HKC039A, HKC100
5.2 PRESSURE Vacuum gauges with least uncertainty of measurement of –
±0.02 kPa from 0 kPa abs. to 110 kPa abs.
HKC038, HKC068,
5.3 PRESSURE Pressure transducers with least uncertainties of measurement of –
±0.02 kPa from 0 kPa to 200 kPa
±1.2 kPa from 200 kPa to 10000 kPa,
±5 kPa from 10000 kPa to 60000 kPa,
±120 kPa from 60000 kPa to 100000 kPa
HKC038, HKC039, HKC039A, HKC100
         
6.1 FLOW Gas meters with least uncertainties of measurement of –
Air
±1.6% of F.S. from 0 Std mL/min to 300 Std mL/min,
±1.6% of F.S. from 0 Std L/min to 30 Std L/min,
±2.1% of reading or 0.05 Std L/min, whichever is greater, from 0 Std L/min to 300 Std L/min
 
6.2 FLOW Liquid meters with least uncertainty of measurement of –
Water, total volume of,
±1 L from 0 L to 400 L
HKC036
         
7.1 ACOUSTIC Sound level meters with least uncertainty of measurement of –
±0.12 dB at 94 dB & 114 dB
HKC016
         
8.1 FREQUENCY AND TIME Tachometers with least uncertainty of measurement of –
(±0.001% ± 1 digit) from 0 RPM to 60000 RPM
HKC015
         
9.1 MASS mass standards with least uncertainty of measurement of –
±0.2 mg from 5 mg to 220 g
HKC009
9.2 MASS Precision laboratory balances with least uncertainty of measurement of –
±0.1 mg from 5 mg to 220 g
HKC009
9.3 MASS Industrial balances with least uncertainty of measurement of –
±3 g up to 70 kg
HKC010
         
10.1 FORCE Load cells with least uncertainties of measurement of –
±10 N from 0 to 50 kN,
±25 N up to 500 kN,
HKC055, HKC060

 

Definitions and metrology concepts taken into account when we perform our measurements:-

1: Measurement

– process of experimentally obtaining one or more quantity values that can reasonably be attributed to a quantity

2: Metrology

– science of measurement and its application

3: Measurand

– quantity intended to be measured

4: Measurement principle

– principle of measurement
– phenomenon serving as a basis of a measurement

5: Measurement method

– method of measurement

6: Measurement procedure

– detailed description of a measurement according to one or more measurement principles and to a given measurement method, based on a measurement model and including any calculation to obtain a measurement result

7: Reference measurement procedure

– measurement procedure accepted as providing measurement results fit for their intended use in assessing measurement trueness of measured quantity values obtained from other measurement procedures for quantities of the same kind, in calibration, or in characterizing reference materials

8: Primary reference measurement

– procedure
– primary reference procedure
– reference measurement procedure used to obtain a measurement result without relation to a measurement standard for a quantity of the same kind

9: Measurement result result of measurement

– set of quantity values being attributed to a measurand together with any other available relevant information

10: Measured quantity value

– value of a measured quantity
– measured value
– quantity value representing a measurement result

11: True quantity value

– true value of a quantity
– true value
– quantity value consistent with the definition of a quantity

12: Conventional quantity value

– conventional value of a quantity
– conventional value
– quantity value attributed by agreement to a quantity for a given purpose

13: Measurement accuracy

– accuracy of measurement
– accuracy
– closeness of agreement between a measured quantity value and a true quantity value of a measurand

14: Measurement trueness

– trueness of measurement
– trueness
– closeness of agreement between the average of an infinite number of replicate measured quantity values and a reference quantity value

15: Measurement precision

– precision
– closeness of agreement between indications or measured quantity values obtained by replicate measurements on the same or similar objects under specified conditions

16: Measurement error

– error of measurement
– error
– measured quantity value minus a reference quantity value

17: Systematic measurement error

– systematic error of measurement
– systematic error
– component of measurement error that in replicate measurements remains constant or varies in a predictable manner

18: Measurement bias

– bias
– estimate of a systematic measurement error

19: Random measurement error

– random error of measurement
– random error
– component of measurement error that in replicate
– measurements varies in an unpredictable manner

20: Repeatability condition of measurement

– repeatability condition
– condition of measurement, out of a set of conditions that includes the same measurement procedure, same operators, same measuring system, same operating conditions and same location, and replicate measurements on the same or similar objects over a short period of time

21: Measurement repeatability

– repeatability
– measurement precision under a set of repeatability conditions of measurement

22: Intermediate precision condition of

– measurement
– intermediate precision condition
– condition of measurement, out of a set of conditions that includes the same measurement procedure, same location, and replicate measurements on the same or similar objects over an extended period of time, but may include other conditions involving changes

23: Intermediate precision condition of

– measurement
– intermediate precision condition
– condition of measurement, out of a set of conditions that includes the same measurement procedure, same location, and replicate measurements on the same or similar objects over an extended period of time, but may include other conditions involving changes

24: Intermediate precision condition of

– measurement
– intermediate precision condition
– condition of measurement, out of a set of conditions that includes the same measurement procedure, same location, and replicate measurements on the same or similar objects over an extended period of time, but may include other conditions involving changes

25: Reproducibility condition of measurement

– reproducibility condition
– condition of measurement, out of a set of conditions that includes different locations, operators, measuring systems, and replicate measurements on the same or similar objects

26: Measurement reproducibility

– reproducibility
– measurement precision under reproducibility conditions of measurement

27: Measurement uncertainty

– uncertainty of measurement
– uncertainty
– non-negative parameter characterizing the dispersion of the quantity values being attributed to a measurand, based on the information used

28: Definitional uncertainty

– component of measurement uncertainty resulting from the finite amount of detail in the definition of a measurand

29: Type A evaluation of measurement

– uncertainty
– Type A evaluation
– evaluation of a component of measurement uncertainty by a statistical analysis of measured quantity values obtained under defined measurement conditions

30: Type B evaluation of measurement

– uncertainty
– Type B evaluation
– evaluation of a component of measurement uncertainty determined by means other than a Type A evaluation of measurement uncertainty

31: Standard measurement uncertainty

– standard uncertainty of measurement
– standard uncertainty
– measurement uncertainty expressed as a standard deviation

32: Combined standard measurement

– uncertainty
– combined standard uncertainty
– standard measurement uncertainty that is obtained using the individual standard measurement uncertainties associated with the input quantities in a measurement model

33: Relative standard measurement

– uncertainty
– standard measurement uncertainty divided by the absolute value of the measured quantity value

34: Uncertainty budget

– statement of a measurement uncertainty, of the components of that measurement uncertainty, and of their calculation and combination

35: Expanded measurement uncertainty

– expanded uncertainty
– product of a combined standard measurement uncertainty and a factor larger than the number one

36: Coverage interval

– interval containing the set of true quantity values of a measurand with a stated probability, based on the information available

37: coverage probability

– probability that the set of true quantity values of a measurand is contained within a specified coverage interval

38: coverage factor

– number larger than one by which a combined standard measurement uncertainty is multiplied to obtain an expanded measurement uncertainty

39: Calibration

– operation that, under specified conditions, in a first step, establishes a relation between the quantity values with measurement uncertainties provided by measurement standards and corresponding indications with associated measurement uncertainties and, in a second step, uses this information to establish a relation for obtaining a measurement result from an indication

40: Calibration hierarchy

– sequence of calibrations from a reference to the final measuring system, where the outcome of each calibration depends on the outcome of the previous calibration

41: Metrological traceability

– property of a measurement result whereby the result can be related to a reference through a documented unbroken chain of calibrations, each contributing to the measurement uncertainty

42: Traceability

– The abbreviated term “traceability” is sometimes used to mean metrological traceability as well as other concepts, such as ‘sample traceability’ or ‘document traceability’ or ‘instrument traceability’ or ‘material traceability’, where the history (“trace”) of an item is meant. Therefore, the full term of “metrological traceability” is preferred if there is any risk of confusion.

43: The ILAC considers the elements for confirming metrological traceability to be an unbroken metrological traceability chain to an international measurement standard or a national measurement standard, a documented measurement uncertainty, a documented measurement procedure, technical competence, metrological traceability to the SI, and calibration intervals

44: Metrological traceability chain

– traceability chain
– sequence of measurement standards and calibrations that is used to relate a measurement result to a reference

45: Metrological traceability to

– a measurement unit
– metrological traceability to a unit
– metrological traceability where the reference is the definition of a measurement unit through its practical realization

46: Verification

– provision of objective evidence that a given item fulfills specified requirements

47: Validation

– verification, where the specified requirements are adequate for an intended use

48: Metrological comparability of

– measurement results
– metrological comparability
– comparability of measurement results, for quantities of a given kind, that are metrologically traceable to the same reference

49: Metrological compatibility of

– measurement results
– metrological compatibility
– property of a set of measurement results for a specified measurand, such that the absolute value of the difference of any pair of measured quantity values from two different measurement results is smaller than some chosen multiple of the standard measurement uncertainty of that difference

50: Measurement model

– model of measurement
– model
– mathematical relation among all quantities known to be involved in a measurement