{
  "url": "https://openlegislation.uk/eu-regulation-2017-655/annex/appendix-2",
  "json_url": "https://openlegislation.uk/eu-regulation-2017-655/annex/appendix-2.json",
  "legislation": "eur/2017/655",
  "legislation_title": "Commission Delegated Regulation (EU) 2017/655 of 19 December 2016 supplementing Regulation (EU) 2016/1628 of the European Parliament and of the Council with regard to monitoring of gaseous pollutant emissions from in-service internal combustion engines installed in non-road mobile machinery (Text with EEA relevance)",
  "legislation_url": "https://openlegislation.uk/eu-regulation-2017-655",
  "path": "annex/appendix/2",
  "kind": "appendix",
  "number": "2",
  "heading": null,
  "text": "Test procedure for in-service monitoring with a PEMS\n1.\nTest parameters\nThe gaseous pollutant emissions to be measured and recorded during the in-service monitoring test are: carbon monoxide (CO), total hydrocarbons (HC) and nitrogen oxides (NOx). Additionally, carbon dioxide (CO2) shall be measured to enable the calculation procedures described in Appendix 5.\nThe parameters set out in the Table shall be measured and recorded during the in-service monitoring test:\nTable\nTest parameters\nMeasured or corrected to a wet basis.\nDirect measurement of exhaust mass flow shall be used unless one of the following is applicable:\n(a) the exhaust system installed in the non-road mobile machinery results in dilution of the exhaust by air upstream of the location where an EFM could be installed. In this case the exhaust sample shall be taken upstream of the point of dilution; or,\n(b) the exhaust system installed in the non-road mobile machinery diverts a portion of the exhaust to another part of the non-road mobile machinery (e.g. for heating) upstream of the location where an EFM could be installed.\nIn these cases, where the manufacturer is able to provide robust evidence to the approval authority of the correlation between the fuel mass flow estimated by the ECU and the fuel mass flow measured on the engine dynamometer test bench, the EFM may be omitted and indirect exhaust flow measurements (from fuel and intake air flows or fuel flow and carbon balance) may be applied.\nUse the ambient temperature sensor or an intake air temperature sensor. Use of an intake air temperature sensor shall comply with the requirements set out in the second paragraph of point 5.1.\nThe recorded value shall be either (a) the net torque; or (b) the net torque calculated from the actual engine percent torque, the friction torque and the reference torque, according to standards set out in point 2.1.1 of Appendix 7.\nThe basis for the net torque shall be uncorrected net torque delivered by the engine inclusive of the equipment and auxiliaries to be included for an emissions test in accordance with Appendix 2 of Annex VI to Delegated Regulation (EU) 2017/654.\nParameter\nUnit\nSource\nHC concentration\nppm\nGas analyser\nCO concentration\nppm\nGas analyser\nNOx concentration\nppm\nGas analyser\nCO2 concentration\nppm\nGas analyser\nExhaust mass flow\nkg/h\nEFM\nExhaust temperature\n°K\nEFM or ECU or Sensor\nAmbient temperature\n°K\nSensor\nAmbient pressure\nkPa\nSensor\nRelative humidity\n%\nSensor\nEngine torque\nNm\nECU or Sensor\nEngine speed\nrpm\nECU or Sensor\nEngine fuel flow\ng/s\nECU or Sensor\nEngine coolant temperature\n°K\nECU or Sensor\nEngine intake air temperature\n°K\nECU or Sensor\nNon-road mobile machinery latitude\ndegree\nGPS (optional)\nNon-road mobile machinery longitude\ndegree\nGPS (optional)\n2.\nMinimum test duration\nThe test duration, comprising all operating sequences and only including valid data, shall be long enough to complete between five and seven times the work performed during the NRTC or to produce between five and seven times the CO2 reference mass in kg/cycle from the NRTC.\n3.\nPreparation of the non-road mobile machinery\nThe preparation of the non-road mobile machinery shall comprise at least the following:\n(a) the check of the engine: any identified problems, once solved, shall be recorded and presented to the approval authority;\n(b) the replacement of the oil, fuel and reagent, if any;\n(c) demonstration of the availability of the ECU data stream information, according to the requirements set out in point 2 of Appendix 7.\n4.\nInstallation of the PEMS\n4.1.\nThe installation of the PEMS shall not influence the non-road mobile machinery gaseous pollutant emissions or performance.\nIn any case, the installation shall comply with the locally applicable safety regulations and insurance requirements and shall follow the instructions issued by the PEMS, measurement instruments, transfer line and sampling probe manufacturer.\n4.2.\nElectrical power supply\nThe electrical power supply of the PEMS shall, be provided by an external power supply unit.\n4.2.1.\nWhen the manufacturer demonstrates to the approval authority that it is not possible to comply with point 4.2, a source drawing its energy (directly or indirectly) from the engine during the test may be used.\n4.2.2.\nIn this case, the peak power consumption of the PEMS shall not exceed 1 % of the engine maximum power, and additional measures shall be taken to prevent the excessive discharge of the battery when the engine is not running or idling.\n4.3.\nMeasurement instruments other than the EFM\nAs far as possible, the measurement instruments other than the EFM shall be installed in a location subject to minimal:\n(a) ambient temperature changes;\n(b) ambient pressure changes;\n(c) electromagnetic radiation;\n(d) mechanical shock and vibration;\n(e) ambient hydrocarbons — if using a FID analyser that uses ambient air as FID burner air.\n4.4.\nEFM\nThe installation of the EFM shall not increase the backpressure beyond the value recommended by the manufacturer.\n4.4.1.\nThe EFM shall be attached to the non-road mobile machinery's tailpipe. The EFM's sensors should be placed between two pieces of straight tube whose length should be at least 2 times the EFM diameter (upstream and downstream).\n4.4.2.\nThe EFM shall be placed after the non-road mobile machinery silencer, to limit the effect of exhaust gas pulsations upon the measurement signals.\n4.5.\nTransfer line and sampling probe\nThe transfer line shall be properly insulated at the connection points (sampling probe and back of the measurement instruments).\n4.5.1.\nIf the length of the transfer line is changed, the transport times shall be verified and if necessary corrected.\n4.5.2.\nThe transfer line and the sampling probe shall be installed in accordance with the requirements set out in Section 9.3 of Annex VI to Delegated Regulation (EU) 2017/654.\n4.6.\nData logger\nThe data logger shall be connected with the engine ECU to record the engine parameters listed in Table 1 of Appendix 7, and, where applicable, the engine parameters listed in Table 2 of Appendix 7.\n4.7.\nGPS (where applicable)\nThe antenna should be mounted at the highest possible location, without risking interference with any obstructions encountered during in-use operation.\n5.\nPre-in-service monitoring test procedures\n5.1.\nAmbient temperature measurement\nThe ambient temperature shall be measured at the beginning of the test and also at the end of the test within a reasonable distance from the non-road mobile machinery. It is allowed to use the CAN signal for intake air temperature (temperature experienced by the engine).\nIf an intake air temperature sensor is used to estimate the ambient temperature the recorded ambient temperature shall be the intake air temperature adjusted by the applicable nominal offset between ambient and intake air temperature as specified by the manufacturer.\n5.2.\nStarting and stabilising the measurement instruments\nThe measurement instruments shall be warmed up and stabilised until pressures, temperatures and flows have reached their operating set points, according to the instructions issued by the measurement instrument/PEMS manufacturer.\n5.3.\nCleaning and heating the transfer line\nTo prevent system contamination, the transfer line shall be purged until sampling begins, according to the instructions issued by the transfer line/PEMS manufacturer.\nThe transfer line shall be heated to 190 °C (+/– 10 °C) before starting the test to avoid the presence of cold spots that could lead to a contamination of the sample by condensed hydrocarbons.\n5.4.\nChecking and calibrating the gas analysers\nThe zero and span calibration and the linearity checks of the gas analysers shall be performed using the analytical gases set out in point 2.1.3 of Appendix 1.\n5.5.\nCleaning the EFM\nThe EFM shall be purged at the pressure transducer connections in accordance with the instructions issued by the PEMS or EFM manufacturer. This procedure shall remove condensation and diesel particulate matter from the pressure lines and the associated flow tube pressure measurement ports.\n6.\nIn-service monitoring test data logging\n6.1.\nBefore the in-service monitoring test\nGaseous pollutant emissions data sampling, measurement of the exhaust parameters and recording of the engine and ambient data shall start prior to starting the engine.\n6.2.\nDuring the in-service monitoring test\nGaseous pollutant emissions data sampling, measurement of the exhaust parameters and recording of the engine and ambient data shall continue throughout the normal in-use operation of the engine.\nThe engine may be stopped and started, but the gaseous pollutant emissions data sampling, measurement of the exhaust parameters and recording of the engine and ambient data shall continue throughout the entire in-service monitoring test.\n6.3.\nAfter the in-service monitoring test\nAt the end of the in-service monitoring test, sufficient time shall be given to the measurement instruments and data logger to allow their response times to elapse. The engine may be shut down before or after data logging is stopped.\n6.4.\nValid measured data for gaseous pollutant emissions calculation\nThe valid measured data for the gaseous pollutant emissions calculations shall be determined in accordance with Appendix 4. Point 6.4.2 shall apply to those calculations.\n6.4.1.\nIn order to determine the duration of the take-off phase after a long non-working event, as set out in point 2.2.2 of Appendix 4, the exhaust gas temperature shall be measured during the operating sequence within 30 cm of the outlet of the after-treatment device used for NOx reduction.\n6.4.2.\nCold start data\nCold start gaseous pollutant emissions measured data shall be removed for the gaseous pollutant emissions calculations.\nValid measured data for gaseous pollutant emissions calculations shall start after the engine coolant temperature has reached 343 K (70 °C) for the first time or after the engine coolant temperature is stabilised within +/– 2 K over a period of 5 minutes, whichever comes first; in any case it shall start no later than 20 minutes after starting the engine.\n7.\nChecking of gas analysers\n7.1.\nZero periodic verification during the operating sequence\nZero verification of the gas analysers shall be conducted at least every 2 hours during an in-service monitoring test.\n7.2.\nZero periodic correction during the in-service monitoring test\nThe results obtained with the checks performed in accordance with point 7.1 may be used to perform a zero drift correction.\n7.3.\nDrift verification after performing the test\nThe drift verification shall be performed only if no zero drift correction was made during the in-service monitoring test in accordance with point 7.2.\n7.3.1.\nNo later than 30 minutes after the in-service monitoring test is completed, the gas analysers shall be zeroed and spanned in order to verify their drift compared to the pre-test results.\n7.3.2.\nThe zero, span and linearity checks of the gas analysers shall be performed as set out in point 5.4.\n8.\nEngine malfunction\n8.1.\nIn the case that a malfunction occurs during an operating sequence and the non-road mobile machinery operator is clearly notified by the on-board diagnostics system via a malfunction visual warning, text message or other indicator, the in-service monitoring test shall be considered void.\n8.2.\nAny malfunction shall be corrected before any further in-service monitoring test is carried out on the engine.",
  "extent": "E+W+S+N.I.",
  "status": null,
  "version": "current",
  "annotations": [
    {
      "type": "footnote",
      "label": "f1",
      "text": "Measured or corrected to a wet basis."
    },
    {
      "type": "footnote",
      "label": "f2",
      "text": "Direct measurement of exhaust mass flow shall be used unless one of the following is applicable: (a) the exhaust system installed in the non-road mobile machinery results in dilution of the exhaust by air upstream of the location where an EFM could be installed. In this case the exhaust sample shall be taken upstream of the point of dilution; or, (b) the exhaust system installed in the non-road mobile machinery diverts a portion of the exhaust to another part of the non-road mobile machinery (e.g. for heating) upstream of the location where an EFM could be installed. In these cases, where the manufacturer is able to provide robust evidence to the approval authority of the correlation between the fuel mass flow estimated by the ECU and the fuel mass flow measured on the engine dynamometer test bench, the EFM may be omitted and indirect exhaust flow measurements (from fuel and intake air flows or fuel flow and carbon balance) may be applied."
    },
    {
      "type": "footnote",
      "label": "f3",
      "text": "Use the ambient temperature sensor or an intake air temperature sensor. Use of an intake air temperature sensor shall comply with the requirements set out in the second paragraph of point 5.1."
    },
    {
      "type": "footnote",
      "label": "f4",
      "text": "The recorded value shall be either (a) the net torque; or (b) the net torque calculated from the actual engine percent torque, the friction torque and the reference torque, according to standards set out in point 2.1.1 of Appendix 7. The basis for the net torque shall be uncorrected net torque delivered by the engine inclusive of the equipment and auxiliaries to be included for an emissions test in accordance with Appendix 2 of Annex VI to Delegated Regulation (EU) 2017/654."
    }
  ],
  "outstanding_effects": [],
  "provenance": {
    "source": "legislation.gov.uk",
    "source_url": "https://www.legislation.gov.uk/eur/2017/655/annex/appendix/2",
    "retrieved_at": "2026-11-01T14:45:01.033154+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."
}