metrology, Uncertainty

Type B Evaluation of Standard Uncertainty

The Type B evaluation of uncertainty involves estimating the quantity u^2j, which may be taken as an approximation to the
metrology, quality insurance

Rejection of an Instrument Received for Calibration

If the pooled variance of certain type of instruments is already known, then the particular instrument received for calibration may
metrology, quality insurance

Fixing Maximum Permissible Error of an Instrument

Having known the pooled variance of an instrument, its maximum permissible error may be fixed. For an instrument, the maximum
quality insurance

Maintenance of Laboratory Instruments

Maintenance of Laboratory Instruments , For ensuring the good working of a measuring instrument, not only its calibration but also
metrology

Testing the Authenticity of Observations

Standard deviation S , the square root of pooled variance, may also be used for testing the authenticity of the
quality insurance, Uncertainty

Uses of Pooled Variance

Estimation of Type A Uncertainty of an Instrument In the following paragraphs, an example has been cited for justification and
quality insurance, Uncertainty

Pooled Variance

Pooled variance is the arithmetic mean of a number of variances. Due consideration is being given to their respective degrees
Uncertainty

Numerical Example for Calculation of Type A Evaluationof Standard Uncertainty

Let us consider a case of measurement of mass of a 1 kg mass standard. Observations after applying buoyancy and