BS 7118-1:1990

Committees responsible
National foreword
Method
1. Scope
2. Normative references
3. Symbols and definitions
4. General
5. Uncertainties in individual calibration points
6. Linearity of the calibration graph
7. Fitting the best straight line
8. Detection of outliers
9. Uncertainty of calibration
10. Uncertainty in the use of the calibration graph for
    a single measurement of flow-rate
11. Uncertainty in the average of several flow-rate
    measurements
Annexes
A. Example for a closed conduit
B. Example for an open channel
C. Uncertainty associated with the calibration
    coefficient when using a calibrated or standardized
    flow-meter
D. Extrapolation of the calibration graph
E. Tests for outliers
F. Guidelines for the application of ISO 7066-1
G. Bibliography
Tables
1. Values of the F distribution for selected degrees
    of freedom - Probability level 0,05
2. Value of Student's t at 95% confidence level
A.1 Calibration results
A.2 Component uncertainties
A.3 Quantities required to calculate uncertainty in
    the calibration graph
B.1 Example of the manual computation of the stage-
    discharge relation by the method of least squares
B.2 Tabulated values required to calculate se and smr
B.3 Example of the computation for the uncertainty in
    the daily mean discharge using hourly values of
    discharge
B.4 Tabulated values required to calculate se and X(v)
E.1 Testing of multiple outliers
E.2 Critical values for the extreme deviation outlier
    test
E.3 Polynomial coefficients
Figures
1. Example of grouping data to establish linearity of
    best fit straight line
2. Basic principles for best-fit straight lines
A.1 Discharge coefficient as a function of the Reynolds
    number
A.2 Discharge coefficient as a function of 10 cubed /
    ((Red) to the power 1/2)
B.1 Stage-discharge curve
B.2 Current-meter rating
C.1 Contributions to uncertainty in the value used for C
D.1 Extrapolation of calibration graph method

Guidance on how the uncertainty in a calibration curve of a flow meter, or in the mean of a number of measurements of the same flow rate, may be calculated, in accordance with the principles stated in BS 5844.