{
  "url": "https://openlegislation.uk/eu-regulation-2015-68/annex-XI/appendix-1",
  "json_url": "https://openlegislation.uk/eu-regulation-2015-68/annex-XI/appendix-1.json",
  "legislation": "eur/2015/68",
  "legislation_title": "Commission Delegated Regulation (EU) 2015/68 of 15 October 2014 supplementing Regulation (EU) No 167/2013 of the European Parliament and of the Council with regard to vehicle braking requirements for the approval of agricultural and forestry vehicles (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2015-68",
  "path": "annex/XI/appendix/1",
  "kind": "appendix",
  "number": "1",
  "heading": null,
  "text": "Symbols\nThe following symbols are used in Appendices 2, 3 and 4:\nFMnd and FMd in case of two-axled power-driven vehicles: these symbols may be simplified to corresponding Fi-symbols.\nSymbol\nNotes\nE\nwheelbase\nER\ndistance between coupling point and centre of axle(s) of rigid drawbar towed vehicle (or distance between coupling point and centre of axle(s) of centre-axle towed vehicle)\nε\nthe adhesion utilised by the vehicle: quotient of the maximum braking rate with the anti-lock braking system operative (zAL) and the coefficient of adhesion (k)\nεi\nthe ε-value measured on axle i (in the case of a tractor with a category 3 anti-lock braking system)\nεΗ\nthe ε-value on the high-friction surface\nεL\nthe ε-value on the low-friction surface\nF\nforce [N]\nFbR\nbraking force of the towed vehicle with the anti-lock braking system inoperative\nFbRmax\nmaximum value of FbR\nFbRmaxi\nvalue of FbRmax with only axle i of the towed vehicle braked\nFbRAL\nbraking force of the towed vehicle with the anti-lock braking system operative\nFCnd\ntotal normal reaction of road surface on the un-braked and non-driven axles of the vehicle combination under static conditions\nFCd\ntotal normal reaction of road surface on the un-braked and driven axles of the vehicle combination under static conditions\nFdyn\nnormal reaction of road under dynamic conditions with the anti-lock braking system operative\nFidyn\nFdyn on axle i in case of tractors or drawbar towed vehicle\nFi\nnormal reaction of road surface on axle i under static conditions\nFM\ntotal normal static reaction of road surface on all wheels of the tractor\nFMnd\ntotal normal static reaction of road surface on the un-braked and non-driven axles of the tractor\nFMd\ntotal normal static reaction of road surface on the un-braked and driven axles of the power-driven vehicle\nFR\ntotal normal static reaction of road surface on all wheels of towed vehicle\nFRdyn\ntotal normal dynamic reaction of road surface on the axle(s) of rigid drawbar towed vehicle or centre-axle towed vehicle\nFwM\n0,01 FMnd + 0,015 FMd\ng\nacceleration due to gravity (9,81 m/s2)\nh\nheight of centre of gravity specified by the manufacturer and agreed by the technical service conducting the approval test\nhD\nheight of drawbar (hinge point on towed vehicle)\nhK\nheight of fifth wheel coupling (king pin)\nhR\nheight of centre of gravity of the towed vehicle\nk\ncoefficient of adhesion between tyre and road\nkf\nk-factor of one front axle\nkH\nk-value determined on the high-friction surface\nki\nk-value determined on axle i for a vehicle with a category 3 anti-lock braking system\nkL\nk-value determined on the low-friction surface\nklock\nvalue of adhesion for 100 % slip\nkM\nk-factor of the tractor\nkpeak\nmaximum value of the curve ‘adhesion versus slip’\nkr\nk-factor of one rear axle\nkR\nk-factor of the towed vehicle\nP\nmass of individual vehicle [kg]\nR\nratio of kpeak to klock\nt\ntime interval [s]\ntm\nmean value of t\ntmin\nminimum value of t\nz\nbraking rate [m/s2]\nzAL\nbraking rate z of the vehicle with the anti-lock braking system operative\nzC\nbraking rate z of the vehicle combination, with the towed vehicle only braked and the anti-lock braking system inoperative\nzCAL\nbraking rate z of the vehicle combination, with the towed vehicle only braked and the anti-lock braking system operative\nzCmax\nmaximum value of zC\nzCmaxi\nmaximum value of zC, with only axle i of the towed vehicle braked\nzm\nmean braking rate\nzmax\nmaximum value of z\nzMALS\nzAL of the tractor on a ‘split surface’\nzR\nbraking rate z of the towed vehicle with the anti-lock braking system inoperative\nzRAL\nzAL of the towed vehicle obtained by braking all the axles, the tractor un-braked and its engine disconnected\nzRALH\nzRAL on the surface with the high coefficient of adhesion\nzRALL\nzRAL on the surface with the low coefficient of adhesion\nzRALS\nzRAL on the split surface\nzRH\nzR on the surface with the high coefficient of adhesion\nzRL\nzR on the surface with the low coefficient of adhesion\nzRHmax\nmaximum value of zRH\nzRLmax\nmaximum value of zRL\nzRmax\nmaximum value of zR",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "FMnd and FMd in case of two-axled power-driven vehicles: these symbols may be simplified to corresponding Fi-symbols."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2015/68/annex/XI/appendix/1",
    "retrieved_at": "2026-11-01T14:46:56.586941+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."
}