Document ID: chunk:federal_register_of_legislation:F2023C00229:reg:10:p4
Version: federal_register_of_legislation:F2023C00229
Segment Type: reg
Provision Reference: reg 10 (pt 4/30)
Character Range: 531528–534331

is replaced by the following:

    '1.3.1. ESC Test

         During a prescribed sequence of warmed-up engine operating conditions the amounts of the above exhaust emissions shall be examined continuously by taking a sample from the raw or diluted exhaust gas. The test cycle consists of a number of speed and power modes which cover the typical operating range of diesel engines. During each mode the concentration of each gaseous pollutant, exhaust flow and power output shall be determined, and the measured values weighted. For particulate measurement, the exhaust gas shall be diluted with conditioned ambient air using either a partial flow or full flow dilution system. The particulates shall be collected on a single suit- able filter in proportion to the weighting factors of each mode. The grams of each pollutant emitted per kilowatt hour shall be calculated as described in Appendix 1 to this Annex. Additionally, NOx shall be measured at three test points within the control area selected by the Technical Service and the measured values compared to the values calculated from those modes of the test cycle enveloping the selected test points. The NOx control check ensures the effectiveness of the emission control of the engine within the typical engine oper- ating range.'

  (b)     Section 1.3.3 is replaced by the following:

  '1.3.3. ETC Test

         During a prescribed transient cycle of warmed-up engine operating conditions, which is based closely on road-type-specific driving pat- terns of heavy-duty engines installed in trucks and buses, the above pollutants shall be examined either after diluting the total exhaust gas with conditioned ambient air (CVS system with double dilution for particulates) or by determining the gaseous components in the raw exhaust gas and the particulates with a partial flow dilution system. Using the engine torque and speed feedback signals of the engine dynamometer, the power shall be integrated with respect to time of the cycle resulting in the work produced by the engine over the cycle. For a CVS system, the concentration of NOx and HC shall be determined over the cycle by integration of the analyser signal, whereas the concentration of CO, CO2, and NMHC may be determined by integration of the analyser signal or by bag sampling. If mea- sured in the raw exhaust gas, all gaseous components shall be determined over the cycle by integration of the analyser signal. For par- ticulates, a proportional sample shall be collected on a suitable filter. The raw or diluted exhaust gas flow rate shall be determined over the cycle to calculate the mass emission values of the pollutants. The mass emission values shall be related to the engine work to get the grams of each pollutant emitted per kilowatt hour, as described in Appendix