{
  "url": "https://openlegislation.uk/eu-regulation-2009-1222/annex-V/division-4/division-4.2/division-4.2.8/division-4.2.8.1",
  "json_url": "https://openlegislation.uk/eu-regulation-2009-1222/annex-V/division-4/division-4.2/division-4.2.8/division-4.2.8.1.json",
  "legislation": "eur/2009/1222",
  "legislation_title": "Regulation (EC) No 1222/2009 of the European Parliament and of the Council of 25 November 2009 on the labelling of tyres with respect to fuel efficiency and other essential parameters (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2009-1222",
  "path": "annex/V/division/4/division/4.2/division/4.2.8/division/4.2.8.1",
  "kind": "division",
  "number": "4.2.8.1",
  "heading": "Calculation of the peak braking force coefficient",
  "text": "The tyre peak braking force coefficient ( μ peak ) is the highest value of μ(t) before lockup occurs calculated as follows for each test run. Analogue signals should be filtered to remove noise. Digitally recorded signals must be filtered using a moving average technique.\nμ(t) = fh(t) fv(t)\nwhere:\nμ(t) is the dynamic tyre braking force coefficient in real time;\nfh(t) is the dynamic braking force in real time, in N;\nfv(t) is the dynamic vertical load in real time, in N.",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Inserted by Commission Regulation (EU) No 228/2011 of 7 March 2011 amending Regulation (EC) No 1222/2009 of the European Parliament and of the Council with regard to the wet grip testing method for C1 tyres (Text with EEA relevance)."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2009/1222/annex/V/division/4/division/4.2/division/4.2.8/division/4.2.8.1",
    "retrieved_at": "2026-11-01T14:51:03.606681+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."
}