China 6 – Emission Standard

Since the end of 2016, it has been announced that all light-duty vehicles must comply with the Emission Standard China 6a until 01.07.2020 and with the China 6b as of 01.07.2023.

The Ministry of Environmental Protection (MEP) has issued relevant renewals together with AQSIQ, that in the future automobile exhaust catalysts, fuel injection and combustion chamber of engine must be upgraded. Besides, the N2O limits is planned in China 6b, that in comparison to China 5 the pollutant CO should be further reduced by 50%, the THC be reduced by 50%, the NOx reduced by 40% and the PM by 33%. Furthermore, it is implemented that tests should be tested under Worldwide harmonized Light vehicles Test Procedure (WLTP).

But what exactly does this mean to the automobile producer? Which limits must be fulfilled under which test conditions? In the following an overview about China IV will be given and afterwards it will come to the relevant regulations with technical requirements.

Chinas Emission Standards

The Chinese Emission Standards were published together by the MEP and SAC. They comply with the European Emission Standards and are mandatory for the following type of motor categories in new vehicles:

  • Passenger vehicles and heavy-duty vehicles
  • Motorcycles
  • Off-road diesel engines
  • Bus engines
  • Marine engines

Since the introduction of the guideline “National Stage I Emission Standard” in 2001, China’s emission standards have been developing over the past 15 years rapidly. The current emission standard China IV was already implemented throughout the country while China V is already being enforced in key areas. From 2018 China V will implemented throughout the country and from 2020 China VI. More strict emission standards should reduce more than 90% carbon emissions and thus promote the technical development in the automobile industry.

The following tests must be carried out by China VI:

  1. Type test I: Verifying the exhaust emissions after a cold start by normal ambient temperature
  2. Type test II: RDE test
  3. Type test III: Emission of crankcase gases
  4. Type test IV: Evaporation emissions
  5. Type test V: Verifying the durability of pollution control devices
  6. Type test VI: Verifying the exhaust emission of CO, THC and NOx after a cold start by low ambient temperature
  7. Type test VII: Verifying evaporative emissions by refuelling

The development of type test I Verifying the exhaust emissions after a cold start by normal ambient temperature by China 4, China 5 and China 6 shows how the emission standards have been developing and how the requirements are becoming more and more strict.

GB 18352.3-2005 Limits and measurement methods for emissions from light-duty vehicles (China III, IV)

Type test I: Verifying the exhaust emissions after a cold start by normal ambient temperature by China IV
      Limits(g/km)
Category Class CO HC NOx HC+ NOx PM
L1 L2 L3 L2 +L3 L4
PI CI PI CI PI CI PI CI CI
Type 1 all 1.00 0.50 0.10 0.08 0.25 0.30 0.025
Type 2 I RM≤1305 1.00 0.50 0.10 0.08 0.25 0.30 0.025
II 1305≤RM≤1760 1.81 0.63 0.13 0.10 0.33 0.39 0.040
III 1760<RM 2.27 0.74 0.16 0.11 0.39 0.46 0.060
Source:  GB 18352.3-2005 Limits and measurement methods for emissions from light-duty vehicles (China III, IV)

 

In comparison to China IV the limits of CO and HC remain the same by China V, while the limit values of NOx and PM are reduced. Besides the limit values of NMHC and PN will be added.

GB 18352.5-2013 Limits and measurement methods for emissions from light-duty vehicles (China 5)

Type test I: Verifying the exhaust emissions after a cold start by normal ambient temperature by China V
     RM/kg Limits(g/km)
Category Class CO THC NMHC NOx THC+NOx PM PN
  L1 L2 L3 L4 L2+ L4 L5 L6
  PI CI PI CI PI CI PI CI PI CI PI(1) CI PI CI
Type 1 all 1.00 0.50 0.100 0.068 0.060 0.180 0.230 0.0045 0.0045 6.0×1011
Type 2 I RM≤1305 1.00 0.50 0.100 0.068 0.060 0.180 0.230 0.0045 0.0045 6.0×1011
  II 1305≤RM≤1760 1.81 0.63 0.130 0.090 0.075 0.235 0.295 0.0045 0.0045 6.0×1011
  III 1760<RM 2.27 0.74 0.160 0.108 0.082 0.280 0.350 0.0045 0.0045 6.0×1011
(1)     Only applicable to motor vehicles with GDI-Engine
Source: GB 18352.5-2013 Limits and measurement methods for emissions from light-duty vehicles (China 5)

GB 18352.6-2016  Limits and measurement methods for emissions from light-duty vehicles (China 6)

In comparison to China V remain the limit values of HC, NMHC, NOx and PM by China 6a unchanged, while the limit values of CO are reduced and furthermore the limit value of N2O will be introduced.

Type test I: Verifying the exhaust emissions after a cold start by normal ambient temperature by China 6a
      Limits
Category Class   CO THC NMHC NOx N2O PM PN1
      mg/km mg/km mg/km mg/km mg/km mg/km /km
Type 1 all 700 100 68 60 20 4.5 6×1011
Type 2 I TM≤1305 700 100 68 60 20 4.5 6×1011
  II 1305≤TM≤1760 880 130 90 75 25 4.5 6×1011
  III 1760<TM 1000 160 108 82 30 4.5 6×1011
1 Transitional limits for gasoline vehicles of 6×1012 / km before 1.7.2020 permitted
 
Type test I: Verifying the exhaust emissions after a cold start by normal ambient temperature by China 6b
      Limits
Category Class   CO HC NMHC NOx N2O PM PN1
      mg/km mg/km mg/km mg/km mg/km mg/km /km
Type 1 all 500 50 35 35 20 3.0 6×1011
Type 2 I TM≤1305 500 50 35 35 20 3.0 6×1011
  II 1305≤TM≤1760 630 65 45 45 25 3.0 6×1011
  III 1760<TM 740 80 55 50 30 3.0 6×1011
1  Transitional limits for gasoline vehicles of 6×1012 个 / km before 1.7.2020 permitted
Source: GB 18352.6-2016  Limits and measurement methods for emissions from light-duty vehicles (China 6)

 

The limit values of CO, HC, NMHC, NOx and PM based on China 6a will have to decrease significantly and only the limit vales of N2O and PN remain the same.

For further reading: https://www.mittelstandswiki.de/wissen/Gastbeitrag:Emissionsstandards_in_China

Alle Leichtfahrzeuge müssen bis zum 01.07.2020 den Emission-Standard China 6a und ab 01.07.2023 China 6b entsprechen.

All light-duty vehicles must comply with the Emission Standard China 6a until 01.07.2020 and with the China 6b as of 01.07.2023.