{
  "url": "https://openlegislation.uk/eu-regulation-2011-582/annex-IX",
  "json_url": "https://openlegislation.uk/eu-regulation-2011-582/annex-IX.json",
  "legislation": "eur/2011/582",
  "legislation_title": "Commission Regulation (EU) No 582/2011 of 25 May 2011 implementing and amending Regulation (EC) No 595/2009 of the European Parliament and of the Council with respect to emissions from heavy duty vehicles (Euro VI) and amending Annexes I and III to Directive 2007/46/EC of the European Parliament and of the Council (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2011-582",
  "path": "annex/IX",
  "kind": "annex",
  "number": "IX",
  "heading": "SPECIFICATIONS OF REFERENCE FUELS",
  "text": "Technical data on fuels for testing compression ignition and dual-fuel engines\nType: Diesel (B7)\nThe values quoted in the specifications are ‘ true values ’ . In establishment of their limit values the terms of ISO 4259 Petroleum products – Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied.\nThe range for cetane number is not in accordance with the requirements of a minimum range of 4R. However, in the case of a dispute between fuel supplier and fuel user, the terms of ISO 4259 may be used to resolve such disputes provided replicate measurements, of sufficient number to archive the necessary precision, are made in preference to single determinations.\nEven though oxidation stability is controlled, it is likely that shelf life will be limited. Advice shall be sought from the supplier as to storage conditions and life.\nFAME content to meet the specification of EN 14214.\nParameter\nUnit\nLimits\nTest method\nMinimum\nMaximum\nCetane Index\n46,0\nEN ISO 4264\nCetane number\n52,0\n56,0\nEN ISO 5165\nDensity at 15 °C\nkg/m 3\n833,0\n837,0\nEN ISO 12185\nDistillation:\n—\n50 % point\n°C\n245,0\n—\nEN ISO 3405\n—\n95 % point\n°C\n345,0\n360,0\nEN ISO 3405\n—\nfinal boiling point\n°C\n—\n370,0\nEN ISO 3405\nFlash point\n°C\n55\n—\nEN ISO 2719\nCloud point\n°C\n—\n– 10\nEN 23015\nViscosity at 40 °C\nmm 2 /s\n2,3\n3,3\nEN ISO 3104\nPolycyclic aromatic hydrocarbons\n% m/m\n2,0\n4,0\nEN 12916\nSulphur content\nmg/kg\n—\n10,0\nEN ISO 20846\nEN ISO 20884\nCopper corrosion 3hrs, 50 °C\n—\nClass 1\nEN ISO 2160\nConradson carbon residue (10 % DR)\n% m/m\n—\n0,2\nEN ISO 10370\nAsh content\n% m/m\n—\n0,01\nEN ISO 6245\nTotal contamination\nmg/kg\n—\n24\nEN 12662\nWater content\nmg/kg\n—\n200\nEN ISO 12937\nAcid number\nmg KOH/g\n—\n0,1\nEN ISO 6618\nLubricity (HFRR wear scan diameter at 60 °C)\nμm\n—\n400\nEN ISO 12156\nOxidation stability at 110 °C\nh\n20,0\nEN 15751\nFAME\n% v/v\n6,0\n7,0\nEN 14078\nType: Ethanol for dedicated compression-ignition engines (ED95)\nAdditives, such as cetane improver as specified by the engine manufacturer, may be added to the ethanol fuel, as long as no negative side effects are known. If these conditions are satisfied, the maximum allowed amount is 10 % m/m.\nThe values quoted in the specifications are ‘true values’. In establishment of their limit values the terms of ISO 4259 Petroleum products — Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied.\nEquivalent EN/ISO methods will be adopted when issued for properties listed above.\nShould it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of EN 15489 shall be applied.\nParameter\nUnit\nLimits\nTest method\nMinimum\nMaximum\nTotal alcohol (Ethanol incl. content on higher saturated alcohols)\n% m/m\n92,4\nEN 15721\nOther higher saturated mono-alcohols (C3-C5)\n% m/m\n2,0\nEN 15721\nMethanol\n% m/m\n0,3\nEN 15721\nDensity at 15 °C\nkg/m3\n793,0\n815,0\nEN-ISO 12185\nAcidity, calculated as acetic acid\n% m/m\n0,0025\nEN 15491\nAppearance\nBright and clear\nFlashpoint\n°C\n10\nEN 3679\nDry residue\nmg/kg\n15\nEN 15691\nWater content\n% m/m\n6,5\nEN 15489\nEN-ISO 12937\nEN 15692\nAldehydes calculated as acetaldehyde\n% m/m\n0,0050\nISO 1388-4\nEsters calculated as ethylacetat\n% m/m\n0,1\nASTM D1617\nSulphur content\nmg/kg\n10,0\nEN 15485\nEN 15486\nSulphates\nmg/kg\n4,0\nEN 15492\nParticulate contamination\nmg/kg\n24\nEN 12662\nPhosphorus\nmg/l\n0,2\nEN 15487\nInorganic chloride\nmg/kg\n1,0\nEN 15484 or EN 15492\nCopper\nmg/kg\n0,1\nEN 15488\nElectrical Conductivity\nμS/cm\n2,5\nDIN 51627-4 or\nprEN 15938\nTechnical data on fuels for testing positive ignition and dual-fuel engines\nType: Petrol (E10)\nThe values quoted in the specifications are ‘ true values ’ . In establishment of their limit values the terms of ISO 4259 Petroleum products - Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied.\nA correction factor of 0,2 for MON and RON shall be subtracted for the calculation of the final result in accordance with EN 228:2008.\nThe fuel may contain oxidation inhibitors and metal deactivators normally used to stabilise refinery gasoline streams, but detergent/dispersive additives and solvent oils shall not be added.\nEthanol is the only oxygenate that shall be intentionally added to the reference fuel. The ethanol used shall conform to EN 15376.\nThe actual sulphur content of the fuel used for the Type 6 test shall be reported.\nThere shall be no intentional addition of compounds containing phosphorus, iron, manganese, or lead to this reference fuel.\n( 2 ) Equivalent EN/ISO methods will be adopted when issued for properties listed above.\nParameter\nUnit\nLimits\nTest method\nMinimum\nMaximum\nResearch octane number, RON\n95,0\n98,0\nEN ISO 5164\nMotor octane number, MON\n85,0\n89,0\nEN ISO 5163\nDensity at 15 °C\nkg/m 3\n743,0\n756,0\nEN ISO 12185\nVapour pressure (DVPE)\nkPa\n56,0\n60,0\nEN 13016-1\nWater content\nmax 0,05 % v/v\nAppearance at – 7 °C: clear and bright\nEN 12937\nDistillation:\n—\nevaporated at 70 °C\n% v/v\n34,0\n46,0\nEN ISO 3405\n—\nevaporated at 100 °C\n% v/v\n54,0\n62,0\nEN ISO 3405\n—\nevaporated at 150 °C\n% v/v\n86,0\n94,0\nEN ISO 3405\n—\nfinal boiling point\n°C\n170\n195\nEN ISO 3405\nResidue\n% v/v\n—\n2,0\nEN ISO 3405\nHydrocarbon analysis:\n—\nolefins\n% v/v\n6,0\n13,0\nEN 22854\n—\naromatics\n% v/v\n25,0\n32,0\nEN 22854\n—\nbenzene\n% v/v\n—\n1,0\nEN 22854 EN 238\n—\nsaturates\n% v/v\nreport\nEN 22854\nCarbon/hydrogen ratio\nreport\nCarbon/oxygen ratio\nreport\nInduction Period\nminutes\n480\n—\nEN ISO 7536\nOxygen content\n% m/m\n3,3\n3,7\nEN 22854\nSolvent washed gum (Existent gum content)\nmg/100 ml\n—\n4\nEN ISO 6246\nSulphur content\nmg/kg\n—\n10\nEN ISO 20846\nEN ISO 20884\nCopper corrosion 3hrs, 50 °C\n—\nclass 1\nEN ISO 2160\nLead content\nmg/l\n—\n5\nEN 237\nPhosphorus content\nmg/l\n—\n1,3\nASTM D 3231\nEthanol\n% v/v\n9,0\n10,0\nEN 22854\nType: Ethanol (E85)\nThe values quoted in the specifications are ‘true values’. In establishment of their limit values the terms of ISO 4259 Petroleum products — Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied.\nThe actual sulphur content of the fuel used for the emission tests shall be reported.\nEthanol to meet specification of EN 15376 is the only oxygenate that shall be intentionally added to this reference fuel.\nThe unleaded petrol content can be determined as 100 minus the sum of the percentage content of water, alcohols, MTBE and ETBE.\nThere shall be no intentional addition of compounds containing phosphorus, iron, manganese, or lead to this reference fuel.\nParameter\nUnit\nLimits\nTest method\nMinimum\nMaximum\nResearch octane number, RON\n95,0\n—\nEN-ISO 5164\nMotor octane number, MON\n85,0\n—\nEN-ISO 5163\nDensity at 15 °C\nkg/m3\nReport\nISO 3675\nVapour pressure\nkPa\n40,0\n60,0\nEN-ISO 13016-1 (DVPE)\nSulphur content\nmg/kg\n—\n10\nEN 15485 or\nEN 15486\nOxidation stability\nMinutes\n360\nEN-ISO 7536\nExistent gum content (solvent washed)\nmg/100 ml\n—\n5\nEN-ISO 6246\nAppearance\nThis shall be determined at ambient temperature or 15 °C whichever is higher.\nClear and bright, visibly free of suspended or precipitated contaminants\nVisual inspection\nEthanol and higher alcohols\n% v/v\n83\n85\nEN 1601\nEN 13132\nEN 14517\nE DIN 51627-3\nHigher alcohols (C3-C8)\n% v/v\n—\n2,0\nE DIN 51627-3\nMethanol\n% v/v\n1,0\nE DIN 51627-3\nPetrol\n% v/v\nBalance\nEN 228\nPhosphorus\nmg/l\n0,2\nEN 15487\nWater content\n% v/v\n0,3\nEN 15489 or\nEN 15692\nInorganic chloride content\nmg/l\n1\nEN 15492\npHe\n6,5\n9,0\nEN 15490\nCopper strip corrosion\n(3 h at 50 °C)\nRating\nClass 1\nEN ISO 2160\nAcidity, (as acetic acid CH3COOH)\n% m/m\n(mg/l)\n—\n0,005\n(40)\nEN 15491\nElectric Conductivity\nμS/cm\n1,5\nDIN 51627-4\nor\nprEN 15938\nCarbon/hydrogen ratio\nreport\nCarbon/oxygen ratio\nreport\nType: LPG\nBalance shall be read as follows: balance = 100 - C3 - < C3 - > C4.\nThis method may not accurately determine the presence of corrosive materials if the sample contains corrosion inhibitors or other chemicals which diminish the corrosivity of the sample to the copper strip. Therefore, the addition of such compounds for the sole purpose of biasing the test method is prohibited.\nAt the request of the engine manufacturer, a higher MON could be used to perform the type-approval tests.\nParameter\nUnit\nFuel A\nFuel B\nTest method\nComposition:\nEN 27941\nC3-content\n% v/v\n30 ± 2\n85 ± 2\nC4-content\n% v/v\nBalance\nBalance\n< C3, > C4\n% v/v\nMaximum 2\nMaximum 2\nOlefins\n% v/v\nMaximum 12\nMaximum 15\nEvaporation residue\nmg/kg\nMaximum 50\nMaximum 50\nEN 15470\nWater at 0 °C\nFree\nFree\nEN 15469\nTotal sulphur content including odorant\nmg/kg\nMaximum 10\nMaximum 10\nEN 24260, ASTM D 3246\nASTM 6667\nHydrogen sulphide\nNone\nNone\nEN-ISO 8819\nCopper strip corrosion\n(1 h at 40 °C)\nRating\nClass 1\nClass 1\nISO 6251\nOdour\nCharacteristic\nCharacteristic\nMotor octane number\nMinimum 89,0\nMinimum 89,0\nEN 589 Annex B\nType: Natural gas/biomethane\nNotes:\nInerts + C 2+\nValue to be determined at standard conditions 293,2 K (20 °C) and 101,3 kPa.\nCharacteristics\nUnits\nBasis\nLimits\nTest method\nminimum\nmaximum\nReference fuel G R\nComposition:\nMethane\n87\n84\n89\nEthane\n13\n11\n15\nBalance\n% mole\n—\n—\n1\nISO 6974\nSulphur content\nmg/m 3\n—\n10\nISO 6326-5\nNotes:\nInerts (different from N 2 ) + C 2 + C 2+\nValue to be determined at 293,2 K (20 °C) and 101,3 kPa.\nReference fuel G 23\nComposition:\nMethane\n92,5\n91,5\n93,5\nBalance\n% mole\n—\n—\n1\nISO 6974\nN 2\n% mole\n7,5\n6,5\n8,5\nSulphur content\nmg/m 3\n—\n—\n10\nISO 6326-5\nNotes:\nInerts (different from N 2 ) + C 2 + C 2+\nValue to be determined at 293,2 K (20 °C) and 101,3 kPa.\nReference fuel G 25\nComposition:\nMethane\n% mole\n86\n84\n88\nBalance\n% mole\n—\n—\n1\nISO 6974\nN 2\n% mole\n14\n12\n16\nSulphur content\nmg/m 3\n—\n—\n10\nISO 6326-5\nNotes:\nInerts (different from N 2 ) + C 2 + C 2 +.\nValue to be determined at 293,2 K (20 °C) and 101,3 kPa.\nValue to be determined at 273,2 K (0 °C) and 101,3 kPa.\nReference fuel G 20\nComposition:\nMethane\n% mole\n100\n99\n100\nISO 6974\nBalance\n% mole\n—\n—\n1\nISO 6974\nN 2\n% mole\nISO 6974\nSulphur content\nmg/m 3\n—\n—\n10\nISO 6326-5\nWobbe Index (net)\nMJ/m 3\n48,2\n47,2\n49,2",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Substituted by Commission Regulation (EU) No 133/2014 of 31 January 2014 amending, for the purposes of adapting to technical progress as regards emission limits, Directive 2007/46/EC of the European Parliament and of the Council, Regulation (EC) No 595/2009 of the European Parliament and of the Council and Commission Regulation (EU) No 582/2011 (Text with EEA relevance)."
    },
    {
      "type": "F",
      "label": "F2",
      "text": "Substituted by Commission Regulation (EU) No 136/2014 of 11 February 2014 amending Directive 2007/46/EC of the European Parliament and of the Council, Commission Regulation (EC) No 692/2008 as regards emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and Commission Regulation (EU) No 582/2011 as regards emissions from heavy duty vehicles (Euro VI) (Text with EEA relevance)."
    },
    {
      "type": "footnote",
      "label": "f1",
      "text": "The values quoted in the specifications are ‘ true values ’ . In establishment of their limit values the terms of ISO 4259 Petroleum products – Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied."
    },
    {
      "type": "footnote",
      "label": "f2",
      "text": "The range for cetane number is not in accordance with the requirements of a minimum range of 4R. However, in the case of a dispute between fuel supplier and fuel user, the terms of ISO 4259 may be used to resolve such disputes provided replicate measurements, of sufficient number to archive the necessary precision, are made in preference to single determinations."
    },
    {
      "type": "footnote",
      "label": "f3",
      "text": "Even though oxidation stability is controlled, it is likely that shelf life will be limited. Advice shall be sought from the supplier as to storage conditions and life."
    },
    {
      "type": "footnote",
      "label": "f4",
      "text": "FAME content to meet the specification of EN 14214."
    },
    {
      "type": "footnote",
      "label": "f5",
      "text": "Additives, such as cetane improver as specified by the engine manufacturer, may be added to the ethanol fuel, as long as no negative side effects are known. If these conditions are satisfied, the maximum allowed amount is 10 % m/m."
    },
    {
      "type": "footnote",
      "label": "f6",
      "text": "The values quoted in the specifications are ‘true values’. In establishment of their limit values the terms of ISO 4259 Petroleum products — Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied."
    },
    {
      "type": "footnote",
      "label": "f7",
      "text": "Equivalent EN/ISO methods will be adopted when issued for properties listed above."
    },
    {
      "type": "footnote",
      "label": "f8",
      "text": "Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of EN 15489 shall be applied."
    },
    {
      "type": "footnote",
      "label": "f9",
      "text": "The values quoted in the specifications are ‘ true values ’ . In establishment of their limit values the terms of ISO 4259 Petroleum products - Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied."
    },
    {
      "type": "footnote",
      "label": "f10",
      "text": "A correction factor of 0,2 for MON and RON shall be subtracted for the calculation of the final result in accordance with EN 228:2008."
    },
    {
      "type": "footnote",
      "label": "f11",
      "text": "The fuel may contain oxidation inhibitors and metal deactivators normally used to stabilise refinery gasoline streams, but detergent/dispersive additives and solvent oils shall not be added."
    },
    {
      "type": "footnote",
      "label": "f12",
      "text": "Ethanol is the only oxygenate that shall be intentionally added to the reference fuel. The ethanol used shall conform to EN 15376."
    },
    {
      "type": "footnote",
      "label": "f13",
      "text": "The actual sulphur content of the fuel used for the Type 6 test shall be reported."
    },
    {
      "type": "footnote",
      "label": "f14",
      "text": "There shall be no intentional addition of compounds containing phosphorus, iron, manganese, or lead to this reference fuel."
    },
    {
      "type": "footnote",
      "label": "f15",
      "text": "The values quoted in the specifications are ‘true values’. In establishment of their limit values the terms of ISO 4259 Petroleum products — Determination and application of precision data in relation to methods of test have been applied and in fixing a minimum value, a minimum difference of 2R above zero has been taken into account; in fixing a maximum and minimum value, the minimum difference is 4R (R = reproducibility). Notwithstanding this measure, which is necessary for technical reasons, the manufacturer of fuels shall nevertheless aim at a zero value where the stipulated maximum value is 2R and at the mean value in the case of quotations of maximum and minimum limits. Should it be necessary to clarify whether a fuel meets the requirements of the specifications, the terms of ISO 4259 shall be applied."
    },
    {
      "type": "footnote",
      "label": "f16",
      "text": "The actual sulphur content of the fuel used for the emission tests shall be reported."
    },
    {
      "type": "footnote",
      "label": "f17",
      "text": "Ethanol to meet specification of EN 15376 is the only oxygenate that shall be intentionally added to this reference fuel."
    },
    {
      "type": "footnote",
      "label": "f18",
      "text": "The unleaded petrol content can be determined as 100 minus the sum of the percentage content of water, alcohols, MTBE and ETBE."
    },
    {
      "type": "footnote",
      "label": "f19",
      "text": "There shall be no intentional addition of compounds containing phosphorus, iron, manganese, or lead to this reference fuel."
    },
    {
      "type": "footnote",
      "label": "f20",
      "text": "Balance shall be read as follows: balance = 100 - C3 - < C3 - > C4."
    },
    {
      "type": "footnote",
      "label": "f21",
      "text": "This method may not accurately determine the presence of corrosive materials if the sample contains corrosion inhibitors or other chemicals which diminish the corrosivity of the sample to the copper strip. Therefore, the addition of such compounds for the sole purpose of biasing the test method is prohibited."
    },
    {
      "type": "footnote",
      "label": "f22",
      "text": "At the request of the engine manufacturer, a higher MON could be used to perform the type-approval tests."
    },
    {
      "type": "footnote",
      "label": "f23",
      "text": "Inerts + C 2+"
    },
    {
      "type": "footnote",
      "label": "f24",
      "text": "Value to be determined at standard conditions 293,2 K (20 °C) and 101,3 kPa."
    },
    {
      "type": "footnote",
      "label": "f25",
      "text": "Inerts (different from N 2 ) + C 2 + C 2+"
    },
    {
      "type": "footnote",
      "label": "f26",
      "text": "Value to be determined at 293,2 K (20 °C) and 101,3 kPa."
    },
    {
      "type": "footnote",
      "label": "f27",
      "text": "Inerts (different from N 2 ) + C 2 + C 2+"
    },
    {
      "type": "footnote",
      "label": "f28",
      "text": "Value to be determined at 293,2 K (20 °C) and 101,3 kPa."
    },
    {
      "type": "footnote",
      "label": "f29",
      "text": "Inerts (different from N 2 ) + C 2 + C 2 +."
    },
    {
      "type": "footnote",
      "label": "f30",
      "text": "Value to be determined at 293,2 K (20 °C) and 101,3 kPa."
    },
    {
      "type": "footnote",
      "label": "f31",
      "text": "Value to be determined at 273,2 K (0 °C) and 101,3 kPa."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2011/582/annex/IX",
    "retrieved_at": "2026-11-01T14:50:03.864087+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."
}