GLOBAL REGISTRY - UNECE

1 ECE/TRANS/180 25 January 2007 GLOBAL REGISTRY Created on 18 November 2004, pursuant to Article 6 of the AGREEMENT CONCERNING THE ESTABLISHING OF GLOBAL TECHNICAL REGULATIONS FOR WHEELED VEHICLES, EQUIPMENT AND PARTS WHICH CAN BE FITTED AND/OR BE USED ON WHEELED VEHICLES (ECE/TRANS/132 and ) Done at Geneva on 25 June 1998 Addendum GLOBAL technical regulation No. 4 TEST PROCEDURE FOR COMPRESSION-IGNITION ( ) ENGINES AND POSITIVE-IGNITION ( ) ENGINES FUELLED WITH NATURAL GAS (NG) OR LIQUEFIED PETROLEUM GAS (LPG) WITH REGARD TO THE EMISSION OF POLLUTANTS (Established in the GLOBAL REGISTRY on 15 November 2006) UNITED NATIONS ECE/TRANS/180 page 3 TABLE OF CONTENTS Page A.

2 STATEMENT OF TECHNICAL RATIONALE AND JUSTIFICATION .. 5 B. TEXT OF THE REGULATION .. 7 1. Purpose .. 7 2. Scope .. 7 3. Definitions, symbols and abbreviations .. 7 4. General 14 5. Performance requirements .. 14 6. Test 19 7. Test 8. Emission measurement and 38 9. Measurement equipment .. 61 ANNEXES Annex 1 WHTC engine dynamometer 87 Annex European diesel reference fuel .. 100 Annex United States of America diesel reference fuel 2-D .. 101 Annex 3 Measurement equipment .. 102 Annex 4 Determination of system 119 Annex 5 Carbon flow 121 Annex 6 Example of calculation procedure.

3 124 ECE/TRANS/180 page 4 A. STATEMENT OF TECHNICAL RATIONALE AND JUSTIFICATION 1. TECHNICAL AND ECONOMIC FEASIBILITY The objective of this proposal is to establish a harmonized GLOBAL technical regulation (gtr) covering the type-approval procedure for heavy-duty engine exhaust emissions. The basis will be the test procedure developed by the WHDC informal group of GRPE (see the informal document No. 4 distributed during the forty-sixth GRPE session). Regulations governing the exhaust emissions from heavy-duty engines have been in existence for many years but the test cycles and methods of emissions measurement vary significantly.

4 To be able to correctly determine the impact of a heavy-duty vehicle on the environment in terms of its exhaust pollutant emissions, a laboratory test procedure, and consequently the gtr, needs to be adequately representative of real-world vehicle operation. The proposed regulation is based on new research into the world-wide pattern of real heavy commercial vehicle use. From the collected data, two representative test cycles, a transient test cycle (WHTC) with both cold and hot start requirements and a hot start steady state test cycle (WHSC), have been created covering typical driving conditions in the European Union (EU), the United States of America, Japan and Australia.

5 Alternative emission measurement procedures have been developed by an expert committee in ISO and have been published in ISO 16183. This standard reflects exhaust emissions measurement technology with the potential for accurately measuring the pollutant emissions from future low emission engines. This work has been the basis for future Japanese and the EU emission legislation. In parallel, substantial work has been undertaken on a different basis in the last several years in the United States of America to make major improvements to the emissions measurement procedures, testing protocols, and regulatory structure for both highway heavy-duty and non-road heavy-duty engines.

6 This work is documented in the rulemaking of the United States of America and was published on 13 July 2005. Some of those new testing protocols are already reflected in this gtr. It is recognized by the Contracting Parties to the 1998 Agreement that a long-term goal for highway heavy-duty diesel engine testing and non-road diesel engine testing would be gtrs which are similar in structure and substance with respect to measurement equipment, procedures and requirements. Therefore, the Contracting Parties recognize there will be a need in the future to amend this gtr in order to have as much commonality as is possible between the highway heavy-duty diesel gtr and the non-road diesel gtr currently under development.

7 As discussed below, this gtr does not contain emission limit values. When this gtr is amended in the future to include limit values, that may be the appropriate time to reconcile any substantive differences between the world-wide heavy-duty certification procedure (WHDC) gtr and the future gtr on non-road mobile machinery (NRMM). At this stage, the limit values shall be developed by the Contracting Parties according to their own rules of procedure. ECE/TRANS/180 page 5 The WHTC and WHSC test procedures reflect world-wide on-road heavy-duty engine operation, as closely as possible, and provide a marked improvement in the realism of the test procedure for measuring the emission performance of existing and future heavy-duty engines.

8 In summary, the test procedure was developed so that it would be: (a) representative of world-wide on-road vehicle operations, (b) able to provide the highest possible level of efficiency in controlling on-road emissions, (c) corresponding to state-of-the-art testing, sampling and measurement technology, (d) applicable in practice to existing and foreseeable future exhaust emissions abatement technologies, and (e) capable of providing a reliable ranking of exhaust emission levels from different engine types. At this stage, the gtr is being presented without limit values.

9 In this way, the test procedure can be given a legal status, based on which the Contracting Parties are required to start the process of implementing it into their national law. The gtr contains several options, whose adoption is left to the discretion of the Contracting Parties. Those options are related to the hot soak procedure between the cold and hot WHTC, the weighting factor of cold and hot WHTC, the particulate filter material and size, and the reference fuel. However, these aspects have to be fully harmonized when common limit values are established.

10 When implementing the test procedure contained in this gtr as part of their national legislation or regulation, Contracting Parties are invited to use limit values which represent at least the same level of severity as their existing regulations, pending the development of harmonized limit values by the Executive Committee ( ) under the 1998 Agreement administered by the World Forum for Harmonization of Vehicle Regulations ( ). The performance levels (emissions test results) to be achieved in the gtr will, therefore, be discussed on the basis of the most recently agreed legislation in the Contracting Parties, as required by the 1998 Agreement.