(e)

Appendix 1 is amended as follows: Section 2.1 is replaced by the following: ‘2.1. Preparation of the Sampling Filter At least one hour before the test, each filter shall be placed in a partially covered petri dish which is protected against dust contamination, and placed in a weighing chamber for stabilisation. At the end of the stabilisation period each filter shall be weighed and the tare weight shall be recorded. The filter shall then be stored in a closed petri dish or sealed filter holder until needed for testing. The filter shall be used within eight hours of its removal from the weighing chamber. The tare weight shall be recorded.’ Section 2.7.4. is replaced by the following: ‘2.7.4. Particulate Sampling One filter shall be used for the complete test procedure. The modal weighting factors specified in the test cycle procedure shall be taken into account by taking a sample proportional to the exhaust mass flow during each individual mode of the cycle. This can be achieved by adjusting sample flow rate, sampling time, and/or dilution ratio, accordingly, so that the criterion for the effective weighting factors in section 5.6 is met. The sampling time per mode must be at least 4 seconds per 0,01 weighting factor. Sampling must be conducted as late as possible within each mode. Particulate sampling shall be completed no earlier than 5 seconds before the end of each mode.’ The following new section 4 is inserted: ‘4. CALCULATION OF THE EXHAUST GAS FLOW 4.1. Determination of Raw Exhaust Gas Mass Flow For calculation of the emissions in the raw exhaust, it is necessary to know the exhaust gas flow. The exhaust gas mass flow rate shall be determined in accordance with section 4.1.1 or 4.1.2. The accuracy of exhaust flow determination shall be ± 2,5 % of reading or ± 1,5 % of the engine's maximum value whichever is the greater. Equivalent methods (e.g. those described in section 4.2 of Appendix 2 to this Annex) may be used. 4.1.1. Direct measurement method Direct measurement of the exhaust flow may be done by systems such as: Precautions shall be taken to avoid measurement errors which will impact emission value errors. Such precautions include the careful installation of the device in the engine exhaust system according to the instrument manufacturers’ recommendations and to good engineering practice. Especially, engine performance and emissions shall not be affected by the installation of the device. 4.1.2. Air and fuel measurement method This involves measurement of the air flow and the fuel flow. Air flowmeters and fuel flowmeters shall be used that meet the total accuracy requirement of section 4.1. The calculation of the exhaust gas flow is as follows: q mew = q maw + q mf 4.2. Determination of Diluted Exhaust Gas Mass Flow For calculation of the emissions in the diluted exhaust using a full flow dilution system it is necessary to know the diluted exhaust gas flow. The flow rate of the diluted exhaust (qmdew ) shall be measured over each mode with a PDP-CVS, CFV-CVS or SSV-CVS in line with the general formulae given in section 4.1 of Appendix 2 to this Annex. The accuracy shall be ± 2 % of reading or better, and shall be determined according to the provisions of section 2.4 of Appendix 5 to this Annex.’ pressure differential devices, like flow nozzle, ultrasonic flowmeter, vortex flowmeter. Sections 4 and 5 are replaced by the following: ‘5. CALCULATION OF THE GASEOUS EMISSIONS 5.1. Data Evaluation For the evaluation of the gaseous emissions, the chart reading of the last 30 seconds of each mode shall be averaged and the average concentrations (conc) of HC, CO and NOx during each mode shall be determined from the average chart readings and the corresponding calibration data. A different type of recording can be used if it ensures an equivalent data acquisition. For the NOx check within the control area, the above requirements apply for NOx only. The exhaust gas flow qmew or the diluted exhaust gas flow qmdew , if used optionally, shall be determined in accordance with section 2.3 of Appendix 4 to this Annex. 5.2. Dry/Wet Correction The measured concentration shall be converted to a wet basis according to the following formulae, if not already measured on a wet basis. The conversion shall be done for each individual mode. cwet = kw × cdry For the raw exhaust gas: Text of image or Text of image where: For the diluted exhaust gas: Text of image or, Text of image For the dilution air: KWd = 1 – KW1 Text of image For the intake air: KWa = 1 – KW2 Text of image where: and may be derived from relative humidity measurement, dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the generally accepted formulae. 5.3. NOx correction for humidity and temperature As the NOx emission depends on ambient air conditions, the NOx concentration shall be corrected for ambient air temperature and humidity with the factors given in the following formulae. The factors are valid in the range between 0 and 25 g/kg dry air. 5.4. Calculation of the emission mass flow rates The emission mass flow rate (g/h) for each mode shall be calculated as follows. For the calculation of NOx, the humidity correction factor k h,D, or k h,G, as applicable, as determined according to section 5.3, shall be used. The measured concentration shall be converted to a wet basis according to section 5.2 if not already measured on a wet basis. Values for u gas are given in Table 6 for selected components based on ideal gas properties and the fuels relevant for this Directive. 5.5. Calculation of the specific emissions The emissions (g/kWh) shall be calculated for all individual components in the following way: Text of image where: m gas is the mass of individual gas P n is the net power determined according to section 8.2 in Annex II. The weighting factors used in the above calculation are according to section 2.7.1. Table 6 Values of u gas in the raw and dilute exhaust gas for various exhaust components 5.6. Calculation of the area control values For the three control points selected according to section 2.7.6, the NOx emission shall be measured and calculated according to section 5.6.1 and also determined by interpolation from the modes of the test cycle closest to the respective control point according to section 5.6.2. The measured values are then compared to the interpolated values according to section 5.6.3. 5.6.1. Calculation of the Specific Emission The NOx emission for each of the control points (Z) shall be calculated as follows: m NOx,Z = 0,001587 × c NOx,Z × k h,D × q mew Text of image 5.6.2. Determination of the Emission Value from the Test Cycle The NOx emission for each of the control points shall be interpolated from the four closest modes of the test cycle that envelop the selected control point Z as shown in Figure 4. For these modes (R, S, T, U), the following definitions apply: Speed(R) = Speed(T) = nRT Speed(S) = Speed(U) = nSU Per cent load(R) = Per cent load(S) Per cent load(T) = Per cent load(U). The NOx emission of the selected control point Z shall be calculated as follows: Text of image and: Text of image Text of image Text of image Text of image where: ER, ES, ET, EU = specific NOx emission of the enveloping modes calculated in accordance with section 5.6.1. MR, MS, MT, MU = engine torque of the enveloping modes. x Torque Speed 5.6.3. Comparison of NOx Emission Values The measured specific NOx emission of the control point Z (NOx,Z) is compared to the interpolated value (EZ) as follows: Text of image 6. CALCULATION OF THE PARTICULATE EMISSIONS 6.1. Data Evaluation For the evaluation of the particulates, the total sample masses (m sep) through the filter shall be recorded for each mode. The filter shall be returned to the weighing chamber and conditioned for at least one hour, but not more than 80 hours, and then weighed. The gross weight of the filters shall be recorded and the tare weight (see section 2.1) subtracted, which results in the particulate sample mass m f. If background correction is to be applied, the dilution air mass (m d) through the filter and the particulate mass (m f,d) shall be recorded. If more than one measurement was made, the quotient m f,d/m d shall be calculated for each single measurement and the values averaged. 6.2. Partial Flow Dilution System The final reported test results of the particulate emission shall be determined through the following steps. Since various types of dilution rate control may be used, different calculation methods for q medf apply. All calculations shall be based upon the average values of the individual modes during the sampling period. 6.2.1. Isokinetic systems q medf = q mew × rd Text of image where r a corresponds to the ratio of the cross sectional areas of the isokinetic probe and the exhaust pipe: Text of image 6.2.2. Systems with measurement of CO2 or NOx concentration qmedf = qmew × rd Text of image where: Concentrations measured on a dry basis shall be converted to a wet basis according to section 5.2 of this Appendix. 6.2.3. Systems with CO2 measurement and carbon balance method (*) Text of image where: (concentrations in vol % on wet basis) This equation is based upon the carbon balance assumption (carbon atoms supplied to the engine are emitted as CO2) and determined through the following steps: qmedf = qmew × r d and Text of image 6.2.4. Systems with flow measurement qmedf = qmew × rd Text of image 6.3. Full Flow Dilution System All calculations shall be based upon the average values of the individual modes during the sampling period. The diluted exhaust gas flow q mdew shall be determined in accordance with section 4.1 of Appendix 2 to this Annex. The total sample mass m sep shall be calculated in accordance with section 6.2.1 of Appendix 2 to this Annex. 6.4. Calculation of the Particulate Mass Flow Rate The particulate mass flow rate shall be calculated as follows. If a full flow dilution system is used, q medf as determined according to section 6.2 shall be replaced with q mdew as determined according to section 6.3. Text of image PTmass = mf msep × qmedf 1000 Text of image qmedf = Σ i = 1 i = n qmedfi × Wfi Text of image msep = Σ i = 1 i = n msepi i = 1, … n The particulate mass flow rate may be background corrected as follows: Text of image PTmass = {mf msep - [mf,d md × Σ i = 1 i = n (1 - 1 Di) × Wfi]} × qmedf 1000 where D shall be calculated in accordance with section 5.4.1 of Appendix 2 to this Annex. (*) The value is only valid for the reference fuel specified in Annex IV.’ " pr | = | water vapour pressure after cooling bath, kPa, pb | = | total atmospheric pressure, kPa, Ha | = | intake air humidity, g water per kg dry air, kf | = | 0,055584 × wALF – 0,0001083 × wBET – 0,0001562 × wGAM + 0,0079936 × wDEL + 0,0069978 × wEPS H a | = | intake air humidity, g water per kg dry air H d | = | dilution air humidity, g water per kg dry air for compression ignition engines: Text of image with: where: H a may be derived from relative humidity measurement, dewpoint measurement, vapour pressure measurement or dry/wet bulb measurement using the generally accepted formulae. T a | = | temperature of the intake air, K H a | = | humidity of the intake air, g water per kg dry air for spark ignition engines k h.G = 0,6272 + 44,030 × 10–3 × H a - 0,862 × 10–3 × H a 2 where: H a may be derived from relative humidity measurement, dew point measurement, vapour pressure measurement or dry/wet bulb measurement using the generally accepted formulae. for the raw exhaust gas m gas = u gas × c gas × q mew where: u gas | = | ratio between density of exhaust component and density of exhaust gas c gas | = | concentration of the respective component in the raw exhaust gas, ppm q mew | = | exhaust mass flow rate, kg/h for the diluted gas m gas = u gas × c gas,c × q mdew where: where: Text of image The dilution factor D shall be calculated according to section 5.4.1 of Appendix 2 to this Annex. u gas | = | ratio between density of exhaust component and density of air c gas,c | = | background corrected concentration of the respective component in the diluted exhaust gas, ppm q mdew | = | diluted exhaust mass flow rate, kg/h Fuel | | NOx | CO | THC/NMHC | CO2 | CH4 Diesel | Exhaust raw | 0,001587 | 0,000966 | 0,000479 | 0,001518 | 0,000553 Exhaust dilute | 0,001588 | 0,000967 | 0,000480 | 0,001519 | 0,000553 Ethanol | Exhaust raw | 0,001609 | 0,000980 | 0,000805 | 0,001539 | 0,000561 Exhaust dilute | 0,001588 | 0,000967 | 0,000795 | 0,001519 | 0,000553 CNG | Exhaust raw | 0,001622 | 0,000987 | 0,000523 | 0,001552 | 0,000565 Exhaust dilute | 0,001588 | 0,000967 | 0,000584 | 0,001519 | 0,000553 Propane | Exhaust raw | 0,001603 | 0,000976 | 0,000511 | 0,001533 | 0,000559 Exhaust dilute | 0,001588 | 0,000967 | 0,000507 | 0,001519 | 0,000553 Butane | Exhaust raw | 0,001600 | 0,000974 | 0,000505 | 0,001530 | 0,000558 Exhaust dilute | 0,001588 | 0,000967 | 0,000501 | 0,001519 | 0,000553 Notes: — u values of raw exhaust based on ideal gas properties at λ = 2, dry air, 273 K, 101,3 kPa — u values of dilute exhaust based on ideal gas properties and density of air — u values of CNG accurate within 0,2 % for mass composition of: C = 66 – 76 %; H = 22 – 25 %; N = 0 – 12 % — u value of CNG for HC corresponds to CH2,93 (for total HC use u value of CH4). c wE | = | wet concentration of the tracer gas in the raw exhaust c wD | = | wet concentration of the tracer gas in the diluted exhaust c wA | = | wet concentration of the tracer gas in the dilution air c (CO2)D | = | CO2 concentration of the diluted exhaust c (CO2)A | = | CO2 concentration of the dilution air Former section 6 is renumbered as section 7.

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Source: EUR-Lex (Cellar) · retrieved 2026-11-10 · Text as adopted (Official Journal); later amendments are not incorporated in this text.