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原文传递 Update to the Determination of CO Basic Emission Rates, OBD and I/M Effects for Tier 1 and Later LDVs and LDTs

题名：	Update to the Determination of CO Basic Emission Rates, OBD and I/M Effects for Tier 1 and Later LDVs and LDTs
作者：	Glover, E. L.; Koupal, J.; Brzezinski, D.
关键词：	Environmental benefits##Determination factors##CO emissions##Later Arrivals##Low Emitting Vehicle (LEV)##Future Standards Vehicles (FSV)##NOx standards##Emission Certification Standards##Emission rates##Methodology##Light-duty vehicles##
摘要：	This document (M6.EXH.012) updates the CO emission factors originally described in the document M6.EXH.009 (April 2001). The update is necessary to account for the changes made in MOBILE6 to account for the effects of Low Emitting Vehicle (LEV) and Tier 2 HC and NOx standards on CO emissions. This document completely supercedes the previous document (M6.EXH.009) and contains all of the descriptions contained in that document, but the descriptions have been updated to reflect the subsequent changes in CO emission rates for MOBILE6. The purpose of this document is to describe the methodology, data analysis and results of the process used to develop basic light duty vehicle CO emission factors, OBD (On-board Diagnostics II) effects, and I/M (Inspection / Maintenance) credits for Tier1, TLEV (Transitional Low Emitting Vehicle), LEV (Low Emitting Vehicle), ULEV (Ultra Low Emitting Vehicle) vehicles (referred collectively throughout the document as Future Standards Vehicles (FSV) for MOBILE6. The document “Determination of NOx and HC Basic Emission Rates, OBD and I/M Effects for Tier1 and Later LDVs and LDTs” (M6.EXH.007) shows the analogous methodology and the results for NOx and HC pollutants for the FSVs. These vehicles are current and future model year cars and light trucks which must meet increasingly stringent tailpipe exhaust emission limits. Of the four types, the first three types (Tier1, TLEV and LEV) are held to the same numerical CO standards. The fourth type (ULEV) meet a more stringent CO standard which is 50 percent of the Tier1 standard. Table 1 shows the emission standards limits in grams per mile for each vehicle type and standard. The limits in units of grams per mile are shown for the 5 year / 50,000 mile certification point. The other important parameter in regards to the certification standards is the model year implementation schedule for all of the standards. This is the percentage of a particular model year and vehicle class that will be required to be certified to the lower standard. This schedule can be found in EPA document EPA420-B-98-001 “Exhaust Emission Certification Standards”. It is available on the EPA-OMS website. The current website address is “http://www.epa.gov/oms/stds-lh.htm” This document (M6EXH.012) also provides a brief explanation of the derivation of CO start and running emissions for all FSV classes (i.e., Tier1, TLEV, LEV and ULEV). Results are also provided in tabular and graphical form. A more detailed explanation of the concept of start and running emissions and their derivation can be found in “Determination of Running Emissions as a Function of Mileage for 1981-1993 Model Year Light-Duty Cars” (M6.EXH.001) and “Determination of Start Emissions as a Function of Mileage and Soak Time for 1981-93 Model Year Light-Duty Vehicles” (M6.STE.003). This document (M6.EXH.012) also explains the I/M credit methodology for 1994 and later model year vehicles, and discusses the algorithm used to predict OBD effectiveness.
总页数：	35
报告类型：	科技报告