Emission standards for new heavy-duty truck and bus engines are based on the European standards. Regulation GB 17691-2005 specifies the emission limits for China III-V stages, which are based on Euro III-V, respectively. The emission limits are shown in Table 1.
|China III||ESC + ELR||2.1||0.66||-||5.0||0.10/0.13†||0.8|
|China IV||ESC + ELR||1.5||0.46||-||3.5||0.02||0.5|
|China V||ESC + ELR||1.5||0.46||-||2.0||0.02||0.5|
|† For engines with a per cylinder displacement of < 0.75 L and rated speed > 3000 rpm|
|At the China I/II stage (not shown in the table), the test was ECE R-49 or the Chinese 9-mode.|
The following provisions apply to emissions of ammonia and nitrogen dioxide:
- NO2 requirements: OEMs are required to report tailpipe NO2 concentration and NO2 increase level if an oxidation catalyst-based aftertreatment system is used, such as DOC, POC, DPF or NAC.
- NH3 slip limit: No limit for China IV. For China V, NH3 slip limit is 25 ppm (peak) and 10 ppm (cycle average).
Implementation dates for the standards are listed in Table 2. The dates generally refer to new type approvals—first registration of existing vehicle models is typically allowed for one more year.
|Standard||Actual Date||Initially Scheduled|
Emission durability requirements, including the engine useful life and the minimum aftertreatment testing periods, are shown in Table 3. The aftertreatment periods according to HJ 438-2008 are mandatory for type approval and production conformity, while GB 20890-2007 provides a guideline to conduct aftertreatment durability testing during product development.
|Category||Useful Life||Aftertreatment Testing|
|GB 20890-2007||HJ 438-2008|
|M1 (GVW > 3.5 t)|
|100,000 km/5 yrs||50,000 km||100,000 km|
|M3 (GVW ≤ 7.5 t)|
N2 and N3 (GVW ≤ 16 t)
|200,000 km/6 yrs||60,000 km||125,000 km|
|M3 (GVW > 7.5 t)|
N3 (GVW > 16 t)
|500,000 km/7 yrs||80,000 km||167,000 km|
The GB 20890-2007 standard recommends that aftertreatment testing be conducted on-vehicle, over the China Heavy-Duty Durability Cycle—Vehicle (C-HDD-V). Alternatively, an engine based durability test can be conducted over the China Heavy-Duty Durability Cycle—Engine (C-HDD-E).