Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:99:p17
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 99 (pt 17/39)
Character Range: 1200015–1203021

Annex 9B and referred to by Annex 8 shall be the one obtained according to Annex 4 when the engine is tested on an engine test bench in diesel mode.

4.7. Requirements to limit Off-Cycle Emissions (OCE) and in-use emissions
              Dual-fuel engines shall be subject to the requirements of Annex 10, whether operating in dual-fuel mode or in the case of Type 1B, Type 2B, and Type 3B in diesel mode.

              4.7.1. PEMS tests at certification

              The PEMS demonstration test at type-approval required in Annex 10 shall be performed by testing the parent engine of a dual-fuel engine family when operating in dual-fuel mode.

              4.7.1.1. In the case of Type 1B, Type 2B and Type 3B dual-fuel engines, an additional PEMS test shall be performed in diesel mode on the same engine and vehicle immediately after or before the PEMS demonstration test performed in dual-fuel mode.

              In that case, certification can only be granted if both the PEMS demonstration test in dual-fuel mode and the PEMS demonstration test in diesel mode have concluded to a pass.

              4.7.2. Additional requirements

              4.7.2.1. Adaptive strategies of a dual-fuel engine are allowed, provided that:

                  (a) The engine always remains in the HDDF type (that is Type 1A, Type 2B, etc.) that has been declared for type-approval; and

                  (b) In case of a Type 2 engine, the resulting difference between the highest and the lowest GERWHTC within the family shall never exceed the percentage specified in paragraph 3.1.1.; and

                  (c) These strategies are declared and satisfy the requirements of Annex 10.

              5. Performance requirements

              5.1. Emission limits applicable to HDDF Type 1A and Type 1B engines

              5.1.1. The emission limits applicable to HDDF Type 1A engines and HDDF Type 1B engines operating in dual-fuel mode are those defined for PI engines in paragraph 5.3. of this Regulation.

              5.1.2. The emission limits applicable to HDDF Type 1B engines operating in diesel mode are those defined for CI engines in paragraph 5.3. of this Regulation.

5.2. Emission limits applicable to HDDF Type 2A and Type 2B engines
              5.2.1. Emission limits applicable over the WHSC test-cycle

              5.2.1.1. For HDDF Type 2A and Type 2B engines, the exhaust emission limits (incl. the PM number limit) over the WHSC test-cycle applicable to HDDF Type 2A engines and HDDF Type 2B engines operating in dual-fuel mode are those applicable to CI engines over the WHSC test-cycle and defined in the table of paragraph 5.3. of this Regulation.

              5.2.1.2. The emission limits (incl. the PM number limit) over the WHSC test-cycle applicable to HDDF Type 2B engines operating in diesel mode are those defined for CI engines in paragraph 5.3. of this Regulation.

              5.2.2. Emission limits applicable over the WHTC test-cycle

              5.2.2.1.