{
  "url": "https://openlegislation.uk/eu-directive-1980-181/annex/chapter-I/division-4",
  "json_url": "https://openlegislation.uk/eu-directive-1980-181/annex/chapter-I/division-4.json",
  "legislation": "eudr/1980/181",
  "legislation_title": "Council Directive of 20 December 1979 on the approximation of the laws of the Member States relating to units of measurement and on the repeal of Directive 71/354/EEC (80/181/EEC)",
  "legislation_url": "https://openlegislation.uk/eu-directive-1980-181",
  "path": "annex/chapter/I/division/4",
  "kind": "division",
  "number": "4",
  "heading": "UNITS AND NAMES OF UNITS PERMITTED IN SPECIALIZED FIELDS ONLY",
  "text": "Quantity\nUnit\nName\nSymbol\nValue\nVergency of optical systems\ndioptre*\n1 dioptre = 1 m -1\nMass of precious stones\nmetric carat\n1 metric carat = 2 × 10 -4 kg\nArea of farmland and building land\nare\na\n1 a = 10 2 m 2\nMass per unit length of textile yarns and threads\ntex*\ntex*\n1 tex = 10 -6 kg · m -1\nBlood pressure and pressure of other body fluids\nMillimetre of mercury\nmm Hg(*)\n1 mm Hg = 133,322 Pa\nEffective cross-sectional area\nBarn\nb\n1 b = 10 -28 m 2",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Inserted by Council Directive of 18 December 1984 amending Directive 80/181/EEC on the approximation of the laws of the Member States relating to units of measurement (85/1/EEC)."
    },
    {
      "type": "X",
      "label": "X1",
      "text": "Substituted by Corrigendum to Council Directive 80/181/EEC of 20 December 1979 on the aproximation of the laws of the Member States relating to units of measurement and on the repeal of Directive 71/354/EEC (Official Journal of the European Communities No L 39 of 15 February 1980)."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eudr/1980/181/annex/chapter/I/division/4",
    "retrieved_at": "2026-11-01T15:23:40.868248+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."
}