{
  "url": "https://openlegislation.uk/eu-regulation-2017-654/annex-VII/appendix-5",
  "json_url": "https://openlegislation.uk/eu-regulation-2017-654/annex-VII/appendix-5.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/appendix/5",
  "kind": "appendix",
  "number": "5",
  "heading": null,
  "text": "Particle number calculation\n1.\nDetermination of particle numbers\n1.1.\nTime alignment\nFor partial flow dilution systems residence time in the particle number sampling and measurement system shall be accounted for by time aligning the particle number signal with the test cycle and the exhaust gas mass flow rate according to the procedure in point 8.2.1.2 of Annex VI. The transformation time of the particle number sampling and measurement system shall be determined in accordance with point 2.1.3.7 of Appendix 1 of Annex VI.\n1.2.\nDetermination of particle numbers for transient (NRTC and LSI-NRTC) test cycles and RMC with a partial flow dilution system\nWhere particle numbers are sampled using a partial flow dilution system according to the specifications set out in point 9.2.3 of Annex VI, the number of particles emitted over the test cycle shall be calculated by means of equation (7-167):\nN = m edf 1,293 × k × c – s × ƒ – r × 10 6\n(7-167)\nWhere:\nN is the number of particles emitted over the test cycle, [#/test],\nmedf is the mass of equivalent diluted exhaust gas over the cycle, determined by means of equation (7-45) (point 2.3.1.1.2), [kg/test],\nk is the calibration factor to correct the particle number counter measurements to the level of the reference instrument where this is not applied internally within the particle number counter. Where the calibration factor is applied internally within the particle number counter, a value of 1 shall be used for k in equation (7-167),\nc s – is the average concentration of particles from the diluted exhaust gas corrected to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nƒ r – is the mean particle concentration reduction factor of the volatile particle remover specific to the dilution settings used for the test.\nwith\nc – s = ∑ i = 1 i = n c s,i n\n(7-168)\nWhere:\ncs,i is a discrete measurement of particle concentration in the diluted exhaust gas from the particle counter, corrected for coincidence and to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nn is the number of particle concentration measurements taken over the duration of the test.\n1.3.\nDetermination of particle numbers for transient (NRTC and LSI-NRTC) test cycles and RMC with a full flow dilution system\nWhere particle numbers are sampled using a full flow dilution system according to the specifications set out in point 9.2.2 of Annex VI, the number of particles emitted over the test cycle shall be calculated by means of equation (7-169):\nN = m edf 1,293 × k × c – s × ƒ – r × 10 6\n(7-169)\nWhere:\nN is the number of particles emitted over the test cycle, [#/test],\nmed is the total diluted exhaust gas flow over the cycle calculated according to any one of the methods described in points 2.2.4.1 to 2.2.4.3, of Annex VII, kg/test,\nk is the calibration factor to correct the particle number counter measurements to the level of the reference instrument where this is not applied internally within the particle number counter. Where the calibration factor is applied internally within the particle number counter, a value of 1 shall be used for k in equation (7-169),\nc s – is the average corrected concentration of particles from the diluted exhaust gas corrected to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nƒ r – is the mean particle concentration reduction factor of the volatile particle remover specific to the dilution settings used for the test.\nwith\nc – = ∑ i = 1 i = n c s,i n\n(7-170)\nWhere:\ncs,i is a discrete measurement of particle concentration in the diluted gas exhaust from the particle counter, corrected for coincidence and to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nn is the number of particle concentration measurements taken over the duration of the test\n1.4.\nDetermination of particle numbers for discrete-mode NRSC with a partial flow dilution system\nWhere particle numbers are sampled using a partial flow dilution system according to the specifications set out in point 9.2.3 of Annex VI, the rate of emission of particles during each individual discrete-mode shall be calculated by means of equation (7-171) using the average values for the mode:\nṄ = q medƒ 1,293 × k × c – s × ƒ – r × 10 6 × 3600\n(7-171)\nWhere:\nṄ is the rate of emission of particles during the individual discrete-mode, [#/h],\nqmedf is the equivalent diluted exhaust mass flow rate on a wet basis during the individual discrete-mode, determined in accordance with equation (7-51) (point 2.3.2.1), [kg/s],\nk is the calibration factor to correct the particle number counter measurements to the level of the reference instrument where this is not applied internally within the particle number counter. Where the calibration factor is applied internally within the particle number counter, a value of 1 shall be used for k in the equation (1-171),\nc s – is the average concentration of particles from the diluted exhaust gas during the individual discrete-mode corrected to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nƒ r – is the mean particle concentration reduction factor of the volatile particle remover specific to the dilution settings used for the test.\nwith\nc – s = ∑ i = 1 i = n c s,i n\n(7-172)\nWhere:\ncs,i is a discrete measurement of particle concentration in the diluted gas exhaust from the particle counter, corrected for coincidence and to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nn is the number of particle concentration measurements taken during the individual discrete-mode sampling period\n1.5.\nDetermination of particle numbers for discrete-mode cycles with a full flow dilution system\nWhere particle numbers are sampled using a full flow dilution system according to the specifications set out in point 9.2.2 of Annex VI, the rate of emission of particles during each individual discrete-mode shall be calculated by means of equation (7-173) using the average values for the mode:\nṄ = q mdew 1,293 × k × c – s × ƒ – r × 10 6 × 3600\n(7-173)\nWhere:\nṄ is the rate of emission of particles during the individual discrete-mode, [#/h],\nqmdew is the total diluted exhaust mass flow rate on a wet basis during the individual discrete-mode, [kg/s],\nk is the calibration factor to correct the particle number counter measurements to the level of the reference instrument where this is not applied internally within the particle number counter. Where the calibration factor is applied internally within the particle number counter, a value of 1 shall be used for k in equation (7-173),\nc s – is the average concentration of particles from the diluted exhaust gas during the individual discrete-mode corrected to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nƒ r – is the mean particle concentration reduction factor of the volatile particle remover specific to the dilution settings used for the test.\nwith\nc – s = ∑ i = 1 i = n c s,i n\n(7-174)\nWhere:\ncs,i is a discrete measurement of particle concentration in the diluted gas exhaust from the particle counter, corrected for coincidence and to standard conditions (273,2 K and 101,33 kPa), particles per cubic centimetre,\nn is the number of particle concentration measurements taken during the individual discrete-mode sampling period.\n2.\nTest result\n2.1.\nCalculation of the specific emissions for transient (NRTC and LSI-NRTC) test cycles and RMC\nFor each applicable individual RMC, hot-start NRTC and cold-start NRTC the specific emissions in number of particles/kWh shall be calculated by means of equation (7-175):\ne = N W act\n(7-175)\nWhere:\nN is the number of particles emitted over the applicable RMC, hot-start run of the NRTC or cold-start NRTC,\nWact is the actual cycle work in accordance with point 7.8.3.4 of Annex VI, [kWh].\nFor an RMC, in case of an engine with infrequent (periodic) exhaust after-treatment system regeneration (see point 6.6.2 of Annex VI), the specific emissions shall be corrected with either the applicable multiplicative adjustment factor or with the applicable adjustment additive factor. In the case that infrequent regeneration did not take place during the test the upward factor shall be applied (k ru,m or k ru,a). In the case that infrequent regeneration took place during the test the downward factor shall be applied (k rd,m or k rd,a).\nFor an RMC the final result shall also be adjusted with the applicable multiplicative or additive deterioration factor established according to the requirements of Annex III.\n2.1.1.\nWeighted average NRTC test result\nFor the NRTC, the final test result shall be a weighted average from cold-start run and hot-start run (including infrequent regeneration where relevant) shall be calculated by means of equation (7-176) or (7-177):\n(a) In the case of multiplicative regeneration adjustment, or engines without infrequently regenerating exhaust after-treatment system\ne = k r 0,1 × N cold + 0,9 × N hot 0,1 × W act,cold + 0,9 × W act,hot\n(7-176)\nIn the case of additive regeneration adjustment\ne = k r + 0,1 × N cold + 0,9 × N hot 0,1 × W act,cold + 0,9 × W act,hot\n(7-177)\nWhere:\nNcold is the total number of particles emitted over the NRTC cold-start run of the NRTC,\nNhot is the total number of particles emitted over the NRTC hot-start run of the NRTC,\nWact,cold is the actual cycle work over the cold-start NRTC in accordance with point 7.8.3.4 of Annex VI, [kWh],\nWact, hot is the actual cycle work over the hot-start NRTC in accordance with point 7.8.3.4 of Annex VI, [kWh],\nkr is the regeneration adjustment, according to point 6.6.2 of Annex VI, or in the case of engines without infrequently regenerating exhaust after-treatment system kr = 1\nIn the case that infrequent regeneration did not take place during the test the upward factor shall be applied (k ru,m or k ru,a). In the case that infrequent regeneration took place during the test the downward factor shall be applied (k rd,m or k rd,a).\nThe result, where applicable inclusive of infrequent regeneration adjustment factor, shall also be adjusted by the applicable multiplicative or additive deterioration factor established according to the requirements of Annex III.\n2.2.\nCalculation of the specific emissions for discrete-mode NRSC tests\nThe specific emissions e [#/kWh] shall be calculated by means of equation (7-178):\ne = ∑ i = 1 N mode Ṅ i × WF i ∑ i = 1 N mode P i × WF i\n(7-178)\nWhere:\nP i engine power for the mode i [kW] calculated by adding to the measured power P meas [kW] the power required to drive auxiliaries P AUX [kW] determined in accordance with equation (6-8) of Annex VI ( P i = P meas + P AUX ).\nWFi is the weighting factor for the mode i [-]\nṄi is the mean emission number flow rate for the mode i [#/h] from equation (7-171) or (7-173) depending upon the dilution method\nIn case of an engine with infrequent (periodic) exhaust after-treatment system regeneration (see point 6.6.2 of Annex VI), the specific emissions shall be corrected with either the applicable multiplicative adjustment factor or with the applicable adjustment additive factor. In the case that infrequent regeneration did not take place during the test the upward factor shall be applied (k ru,m or k ru,a). In the case that infrequent regeneration took place during the test the downward factor shall be applied (k rd,m or k rd,a). Where the adjustment factors have been determined for each mode they shall be applied to each mode during the calculation of the weighted emission result at equation (7-178).\nThe result, where applicable inclusive of infrequent regeneration adjustment factor, shall also be adjusted by the applicable multiplicative or additive deterioration factor established according to the requirements of Annex III.\n2.3.\nRounding of final results\nThe final NRSC and weighted average NRTC test results shall be rounded in one step to three significant figures in accordance with ASTM E 29–06B. No rounding of intermediate values leading to the final brake specific emission result is permissible.\n2.4.\nDetermination of particle number background\n2.4.1.\nAt the engine manufacturer's request, dilution tunnel background particle number concentrations may be sampled, prior to or after the test, from a point downstream of the particle and hydrocarbon filters into the particle number measurement system, to determine the tunnel background particle concentrations.\n2.4.2.\nSubtraction of particle number tunnel background concentrations shall not be allowed for type-approval, but may be used at the manufacturer's request, with the prior approval of the approval authority, for conformity of production testing, if it can be demonstrated that tunnel background contribution is significant, which can then be subtracted from the values measured in the diluted exhaust gas.",
  "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/appendix/5",
    "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."
}