ISO 13752 pdf download

ISO 13752 pdf download.Air quality — Assessment of uncertainty of a measurement method under field conditions using a second method as reference 1 Scope This International Standard specifies a method for assessing the measurement uncertainty of a calibrated measurement method (test method) applied under field conditions using a second method as a reference (reference method). The reference method may not necessarily be a legally prescribed measurement method. The measurement uncertainty is derived from measurements made in parallel on real samples by comparing the measured values of the test method with those of the reference method. The result is only valid within the range of the measurements obtained. The test is designed especially for method validation. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 6879:1 995, Air quality — Performance characteristics and related concepts for air quality measuring methods . ISO 91 69:1 994, Air quality — Determination of performance characteristics of measurement methods NOTES 1 The first assumption can be considered as fluctuations of the background or intercept value b 0 without fluctuations of the slope b 1 and the second as fluctuations of the slope without fluctuations of the background or intercept value. 2 The value of the coefficients of the regression function (estimation of bias) is not seriously affected by deviations from the assumption on the standard deviation. However, the estimated random part of measurement uncertainty heavily depends on the assumption. The general variance function used in this International Standard accounts not only for the variability of intercept and slope but also for statistical noise, the standard deviation of which is proportional to the square root of the value itself (approximately proportional to the square root of x) 5 Requirements 5.1 General The method described in this International Standard requires that: — a linear relationship exists between the variables compared; if the relationship is different but mathematically known the procedure may be adapted. — the measurement errors...