{
  "url": "https://openlegislation.uk/eu-regulation-2017-654/annex-VII/division-3/division-3.5/division-3.5.2",
  "json_url": "https://openlegislation.uk/eu-regulation-2017-654/annex-VII/division-3/division-3.5/division-3.5.2.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/3/division/3.5/division/3.5.2",
  "kind": "division",
  "number": "3.5.2",
  "heading": "Dry-to-wet concentration conversion",
  "text": "Parameters of this point are obtained from the results of the chemical balance calculated in point 3.4.3. The following relation exists between gas molar concentrations in the measured flow x gasdry and x gas [mol/mol] expressed on a dry and wet basis respectively [equations (7-109) and (7-110)]:\nx gasdry = x gas 1 − x H2O\n(7-109)\nx gas = x gasdry 1 + x H2Odry\n(7-110)\nwhere:\nx H2O molar fraction of water in the measured flow on a wet basis [mol/mol]\nx H2Odry molar fraction of water in the measured flow on a dry basis [mol/mol]\nFor gaseous emissions a removed water correction shall be performed for the generic concentration x [mol/mol] by means of equation (7-111):\nx = x emission meas 1 − x H2Oexh 1 − x H2O emission meas\n(7-111)\nWhere:\nx [emission]meas molar fraction of emission in the measured flow at measurement location [mol/mol]\nx H2O[emission]meas amount of water in the measured flow at the concentration measurement [mol/mol]\nx H2Oexh amount of water at the flowmeter [mol/mol]",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2017/654/annex/VII/division/3/division/3.5/division/3.5.2",
    "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."
}