{
  "url": "https://openlegislation.uk/eu-decision-2002-657/annex/chapter-3.5",
  "json_url": "https://openlegislation.uk/eu-decision-2002-657/annex/chapter-3.5.json",
  "legislation": "eudn/2002/657",
  "legislation_title": "Commission Decision of 12 August 2002 implementing Council Directive 96/23/EC concerning the performance of analytical methods and the interpretation of results (notified under document number C(2002) 3044) (Text with EEA relevance) (2002/657/EC)",
  "legislation_url": "https://openlegislation.uk/eu-decision-2002-657",
  "path": "annex/chapter/3.5",
  "kind": "chapter",
  "number": "3.5.",
  "heading": "EXAMPLES FOR THE STANDARD ADDITION METHOD",
  "text": "A test sample with a content T of the analyte is divided in two test portions 1 and 2 of respective masses m1 and m2. The test portion 2 is spiked with a volume VA of a solution of concentration ρA of the analyte. Two extracts of the test portions of respective volumes V1 and V2 are obtained after extraction and purification steps of the method. The recovery of the analyte is supposed to be rc. Both extracts are assayed with a measurement method of sensitivity b and give an analytical response of x1 and x2 respectively.\nIf assumed that rc and b are the same for the analyte in the native sample and in the spiked sample, then the content T can be calculated as:\nT = x 1 . V 1 . ρ A . V A /( x 2 . V 2 . m 1 - x 1 . V 1 . m 2 )\nThe method will allow the determination of the recovery rc. Then, in addition with the assay described above, part of the extract of the test portion 1 (volume V3) is spiked with a known amount ρB.VB of the analyte and assayed. The analytical response is x3 and the recovery is:\nrc = x 2 . V 1 . V 2 . ρ B . V B /[ x 3 . V 1 . V 3 (T. m 2 + ρ A . V A ) - x 2 . V 2 .T. m 1 ( V 3 - V B )]\nMoreover, it is possible to calculate the sensitivity b, as:\nb = x 1 . V 1 /rc.T. m 1\nAll conditions of application and details have been described (18).",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eudn/2002/657/annex/chapter/3.5",
    "retrieved_at": "2026-11-01T15:18:31.211349+00:00"
  },
  "licence": "Open Government Licence v3.0",
  "licence_url": "https://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/",
  "attribution": "Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives."
}