Commission Regulation (EC) No 333/2007Show full title

C.3.1. Definitions U.K.

The following definitions shall apply:

‘r’

=

Repeatability the value below which the absolute difference between single test results obtained under repeatability conditions (i.e., same sample, same operator, same apparatus, same laboratory, and short interval of time) may be expected to lie within a specific probability (typically 95 %) and hence r = 2,8 × s_r.

‘s_r’

=

Standard deviation calculated from results generated under repeatability conditions.

‘RSD_r’

=

Relative standard deviation calculated from results generated under repeatability conditions [(s_r/) × 100].

‘R’

=

Reproducibility the value below which the absolute difference between single test results obtained under reproducibility conditions (i.e., on identical material obtained by operators in different laboratories, using the standardised test method), may be expected to lie within a certain probability (typically 95 %); R = 2,8 × s_R.

‘s_R’

=

Standard deviation, calculated from results under reproducibility conditions.

‘RSD_R’

=

Relative standard deviation calculated from results generated under reproducibility conditions [(s_R/) × 100].

‘LOD’

=

Limit of detection, smallest measured content, from which it is possible to deduce the presence of the analyte with reasonable statistical certainty. The limit of detection is numerically equal to three times the standard deviation of the mean of blank determinations (n > 20).

‘LOQ’

=

Limit of quantification, lowest content of the analyte which can be measured with reasonable statistical certainty. If both accuracy and precision are constant over a concentration range around the limit of detection, then the limit of quantification is numerically equal to six or 10 times the standard deviation of the mean of blank determinations (n > 20).

‘’[F1 HORRAT (1) _r

=

The observed RSD _r divided by the RSD _r value estimated from the (modified) Horwitz equation (2) (cf. point C.3.3.1 (‘Notes to the performance criteria’)) using the assumption r = 0,66 R.]

‘[F1 HORRAT (3) _R ’

=

The observed RSD _R divided by the RSD _R value estimated from the (modified) Horwitz equation (4) (cf. point C.3.3.1 (‘Notes to the performance criteria’)).]

‘[F1 u’

=

Combined standard measurement uncertainty obtained using the individual standard measurement uncertainties associated with the input quantities in a measurement model] (5)

‘U’

=

The expanded measurement uncertainty, using a coverage factor of 2 which gives a level of confidence of approximately 95 % (U = 2u).

‘Uf’

=

Maximum standard measurement uncertainty.

Textual Amendments

F1 Substituted by Commission Regulation (EU) No 836/2011 of 19 August 2011 amending Regulation (EC) No 333/2007 laying down the methods of sampling and analysis for the official control of the levels of lead, cadmium, mercury, inorganic tin, 3-MCPD and benzo(a)pyrene in foodstuffs (Text with EEA relevance).

(1)

[F1 Horwitz W. and Albert, R., 2006, The Horwitz Ratio (HorRat): A useful Index of Method Performance with respect to Precision, Journal of AOAC International, Vol. 89, 1095-1109.]

(2)

[F1 M. Thompson, Analyst, 2000, p. 125 and 385-386.]

(3)

[F1 Horwitz W. and Albert, R., 2006, The Horwitz Ratio (HorRat): A useful Index of Method Performance with respect to Precision, Journal of AOAC International, Vol. 89, 1095-1109.]

(4)

[F1 M. Thompson, Analyst, 2000, p. 125 and 385-386.]

(5)

[F1 International vocabulary of metrology – Basic and general concepts and associated terms (VIM), JCGM 200:2008.]

Textual Amendments

F1 Substituted by Commission Regulation (EU) No 836/2011 of 19 August 2011 amending Regulation (EC) No 333/2007 laying down the methods of sampling and analysis for the official control of the levels of lead, cadmium, mercury, inorganic tin, 3-MCPD and benzo(a)pyrene in foodstuffs (Text with EEA relevance).