Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:13:p19
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 13 (pt 19/27)
Character Range: 687689–690863

shall be made on the basis of surveys and studies of production vehicles.
3. Technical requirements
              3.1. The technical requirements shall be those set out in Annex 5 to Regulation No. 83, with the exception set out in paragraph 3.2.
              3.2. The reference fuels specified in paragraph 2.1. of Annex 5 to Regulation No. 83 shall be understood as referring to the appropriate reference fuel specifications set out in Annex 5 to this Regulation.

Annex 7 Verifying the durability of engine systems

1. Introduction

              1.1. This annex sets out the procedures for selecting engines to be tested over a service accumulation schedule for the purpose of determining deterioration factors. The deterioration factors shall be applied in accordance with the requirements of paragraph 3.6. of this annex to the emissions measured according to Annex 4.

              1.2. This annex also sets out the emission and non-emission-related maintenance carried out on engines undergoing a service accumulation schedule. Such maintenance shall conform to the maintenance performed on in-service engines and shall be communicated to owners of new engines and vehicles.

2. Selection of engines for establishing useful life deterioration factors

              2.1. Engines shall be selected from the engine family defined in accordance with paragraph 7. of this Regulation for emission testing in order to establish useful life deterioration factors.

              2.2. Engines from different engine families may be further combined into families based on the type of exhaust after-treatment system utilised. In order to place engines with different numbers of cylinders and different cylinder configuration but having the same technical specifications and installation for the exhaust after-treatment systems into the same engine-after-treatment system family, the manufacturer shall provide data to the Type Approval Authority that demonstrates that the emissions reduction performance of such engine systems is similar.

2.3. One engine representing the engine-after-treatment system family as determined in accordance with paragraph 2.2., shall be selected by the engine manufacturer for testing over the service accumulation schedule defined in paragraph 3.2., and shall be reported to the Type Approval Authority before any testing commences.
2.3.1. If the Type Approval Authority decides that the worst case emissions of the engine-after-treatment system family can be characterised better by another engine then the test engine shall be selected jointly by the Type Approval Authority and the engine manufacturer.

3. Establishing useful life deterioration factors

3.1. General
               Deterioration factors applicable to an engine-after-treatment system family are developed from the selected engines based on a service accumulation schedule that includes periodic testing for gaseous and particulate emissions over the WHTC and WHSC tests.
3.2. Service accumulation schedule
               Service accumulation schedules may be carried out at the choice of the manufacturer by running a vehicle equipped with the selected engine over an