BS EN ISO 19036:2019
$189.07
Microbiology of the food chain. Estimation of measurement uncertainty for quantitative determinations
Published By | Publication Date | Number of Pages |
BSI | 2019 | 48 |
This document specifies requirements and gives guidance for the estimation and expression of measurement uncertainty (MU) associated with quantitative results in microbiology of the food chain.
It is applicable to the quantitative analysis of:
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products intended for human consumption or the feeding of animals;
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environmental samples in the area of food production and food handling;
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samples at the stage of primary production.
The quantitative analysis is typically carried out by enumeration of microorganisms using a colony-count technique. This document is also generally applicable to other quantitative analyses, including:
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most probable number (MPN) techniques;
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instrumental methods, such as impediometry, adenosine triphosphate (ATP) and flow cytometry;
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molecular methods, such as methods based on quantitative polymerase chain reaction (qPCR).
The uncertainty estimated by this document does not include systematic effects (bias).
PDF Catalog
PDF Pages | PDF Title |
---|---|
2 | undefined |
4 | European foreword Endorsement notice |
7 | Foreword |
8 | Introduction |
9 | 1 Scope 2 Normative references 3 Terms, definitions and symbols 3.1 Terms and definitions |
12 | 3.2 Symbols |
13 | 4 General considerations |
14 | 5 Technical uncertainty 5.1 Identification of main sources of uncertainty 5.1.1 General aspects |
15 | 5.1.2 Sampling uncertainty 5.1.3 Bias 5.1.4 Critical factors |
16 | 5.2 Estimation of technical uncertainty 5.2.1 General aspects 5.2.2 Reproducibility standard deviation derived from intralaboratory experiments, sIR |
21 | 5.2.3 Reproducibility standard deviation derived from interlaboratory studies |
22 | 6 Matrix uncertainty 6.1 General aspects |
23 | 6.2 Case of homogeneous laboratory (or test) sample 6.3 Multiple test portions from laboratory samples |
24 | 6.4 Known characteristic of the matrix |
25 | 7 Distributional uncertainties 7.1 General aspects 7.2 Colony-count technique — Poisson uncertainty 7.3 Colony-count technique — Confirmation uncertainty |
26 | 7.4 Most probable number uncertainty |
27 | 8 Combined and expanded uncertainty 8.1 Combined standard uncertainty 8.1.1 General considerations 8.1.2 Combined standard uncertainty based on separate technical, matrix, and distributional standard uncertainties |
28 | 8.1.3 Combined standard uncertainty based on reproducibility standard deviation alone 8.2 Expanded uncertainty 8.3 Worked examples 8.3.1 Example 1 — Technical, matrix and Poisson components of uncertainty 8.3.2 Example 2 — Poisson component negligible |
29 | 8.3.3 Example 3 — Poisson, matrix and confirmation components 8.3.4 Example 4 — Technical, matrix and most probable number components |
30 | 9 Expression of measurement uncertainty in the test reports 9.1 General aspects |
31 | 9.2 Results below the limit of quantification 9.2.1 General aspects 9.2.2 Example |
33 | Annex A (informative) Calculation of standard deviations with two or more than two test portions (intralaboratory reproducibility standard deviation and matrix uncertainty standard deviation) |
38 | Annex B (informative) Matrix effect and matrix uncertainty |
40 | Annex C (informative) Intrinsic variability (standard uncertainty) of most probable number estimates |
42 | Annex D (informative) Correction of experimental standard deviations for unwanted uncertainty components |
45 | Bibliography |