Division C.3.3.2 ‘Fitness-for-purpose’ approachF1
United Kingdom
For in-house validated methods, as an alternative a ‘fitness-for-purpose’ approachf1 may be used to assess their suitability for official control. Methods suitable for official control must produce results with a combined standard measurement uncertainty (u) less than the maximum standard measurement uncertainty calculated using the formula below:
where:
Uf is the maximum standard measurement uncertainty (μg/kg).
LOD is the limit of detection of the method (μg/kg). The LOD must meet the performance criteria set in point C.3.3.1 for the concentration of interest.
C is the concentration of interest (μg/kg);
α is a numeric factor to be used depending on the value of C. The values to be used are given in F2Table 10.
Table 10
Numeric values to be used for α as constant in formula set out in this point, depending on the concentration of interest
| C (μg/kg) | α |
|---|---|
| ≤ 50 | 0,2 |
| 51-500 | 0,18 |
| 501- 1 000 | 0,15 |
| 1 001 - 10 000 | 0,12 |
| > 10 000 | 0,1 |
The analyst shall note the ‘Report on the relationship between analytical results, measurement uncertainty, recovery factors and the provisions of EU food and feed legislation’f2.
Annotations
Textual amendments
- F1
- F2
Footnotes
- f1
-
M. Thompson and R. Wood, Accred. Qual. Assur., 2006, p. 10 and 471-478.
- f2
-
http://ec.europa.eu/food/food/chemicalsafety/contaminants/report-sampling_analysis_2004_en.pdf