{
  "url": "https://openlegislation.uk/eu-regulation-2017-654/annex-VII/division-2/division-2.1/division-2.1.5/division-2.1.5.2",
  "json_url": "https://openlegislation.uk/eu-regulation-2017-654/annex-VII/division-2/division-2.1/division-2.1.5/division-2.1.5.2.json",
  "legislation": "eur/2017/654",
  "legislation_title": "Commission Delegated Regulation (EU) 2017/654 of 19 December 2016 supplementing Regulation (EU) 2016/1628 of the European Parliament and of the Council with regard to technical and general requirements relating to emission limits and type-approval for internal combustion engines for non-road mobile machinery",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2017-654",
  "path": "annex/VII/division/2/division/2.1/division/2.1.5/division/2.1.5.2",
  "kind": "division",
  "number": "2.1.5.2",
  "heading": "Calculated values",
  "text": "The component specific factor, u gas,i, may be calculated by the density ratio of the component and the exhaust gas or alternatively by the corresponding ratio of molar masses [equations (7-11) or (7-12)]:\nu gas, i = M gas ∕ M e, i × 1000\n(7-11)\nor\nu gas, i = ρ gas ∕ ρ e, i × 1000\n(7-12)\nwhere:\nM gas molar mass of the gas component [g/mol]\nM e, i instantaneous molar mass of the wet raw exhaust gas [g/mol]\nρ gas density of the gas component [kg/m3]\nρ e,i instantaneous density of the wet raw exhaust gas [kg/m3]\nThe molar mass of the exhaust gas, M e,i shall be derived for a general fuel composition CH α O ε N δ S γ under the assumption of complete combustion, and shall be calculated by means of equation (7-13):\nM e,i = 1 + q mf,i q maw,i q mf,i q maw,i × α 4 + ε 2 + δ 2 12,011 + 1,00794 × α + 15,9994 × ε + 14,0067 × δ + 32,065 × γ + H a × 10 − 3 2 × 1,00794 + 15,9994 + 1 M a 1 + H a × 10 − 3\n(7-13)\nWhere:\nqm f, i instantaneous fuel mass flow rate on wet basis [kg/s]\nqm aw, i instantaneous intake air mass flow rate on wet basis [kg/s]\nα molar hydrogen-to-carbon ratio [-]\nδ molar nitrogen-to-carbon ratio [-]\nε molar oxygen-to-carbon ratio [-]\nγ atomic sulphur-to-carbon ratio [-]\nH a intake air humidity [g H2O/kg dry air]\nM a dry intake air molecular mass = 28,965 g/mol\nThe instantaneous raw exhaust gas density ρ e, i [kg/m3] shall be calculated by means of equation (7-14):\nρ e, i = 1000 + H a + 1000 × q m f, i ∕ q m ad, i 773,4 + 1,2434 × H a + k f × 1000 × q m f, i ∕ q m ad, i\n(7-14)\nwhere:\nqm f, i instantaneous fuel mass flow rate [kg/s]\nqm ad, i instantaneous dry intake air mass flow rate [kg/s]\nH a intake air humidity [g H2O/kg dry air]\nk f combustion additional volume [m3/kg fuel] [see equation (7-5)]",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "F",
      "label": "F1",
      "text": "Substituted by Commission Delegated Regulation (EU) 2018/989 of 18 May 2018 amending and correcting Delegated Regulation (EU) 2017/654 supplementing Regulation (EU) 2016/1628 of the European Parliament and of the Council with regard to technical and general requirements relating to emission limits and type-approval for internal combustion engines for non-road mobile machinery (Text with EEA relevance)."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2017/654/annex/VII/division/2/division/2.1/division/2.1.5/division/2.1.5.2",
    "retrieved_at": "2026-11-01T14:45:01.864924+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."
}