Background

European Union emission regulations for new light duty vehicles (cars and light commercial vehicles) are specified in the Directive 70/220/EEC. This basis Directive was amended a number of times, some of the most important amendments including:

Fuels. The 2000/2005 standards were accompanied by an introduction of more stringent fuel regulations that require minimum diesel cetane number of 51 (year 2000), maximum diesel sulfur content of 350 ppm in 2000 and 50 ppm in 2005, and maximum petrol (gasoline) sulfur content of 150 ppm in 2000 and 50 ppm in 2005. “Sulfur-free” diesel and gasoline fuels (≤ 10 ppm S) must be available from 2005, and become mandatory from 2009.

Emission Testing. Emissions are tested over the NEDC (ECE 15 + EUDC) chassis dynamometer procedure. Effective year 2000 (Euro 3), that test procedure was modified to eliminate the 40 s engine warm-up period before the beginning of emission sampling. This modified cold start test is referred to as the New European Driving Cycle (NEDC) or as the MVEG-B test. All emissions are expressed in g/km.

The draft Euro 5/6 implementing legislation adopts a new PM mass emission measurement method (similar to the US 2007 procedure) developed by the UN/ECE Particulate Measurement Programme (PMP) and adjusts the PM mass emission limit to account for differences in results using the old and the new method. The legislation also introduces a particle number emission limit at the Euro 5/6 stage (PMP method), in addition to the mass-based limits. At the time of adoption of the Euro 5/6 regulation, its mass-based PM emission limits could only be met by closed particulate filters. Number-based PM limits would prevent the possibility that in the future open filters are developed that meet the PM mass limit but enable a high number of ultra fine particles to pass.

Emission Standards

Emission standards for passenger cars and light commercial vehicles (vehicle categories M1 and N1, respectively) are summarized in the following tables. Since the Euro 2 stage, EU regulations introduce different emission limits for diesel and gasoline vehicles. Diesels have more stringent CO standards but are allowed higher NOx. Gasoline vehicles are exempted from PM standards through the Euro 4 stage. Euro 5/6 regulations introduce PM mass emission standards, numerically equal to those for diesels, for gasoline cars with DI engines.

All dates listed in the tables refer to new type approvals. The EC Directives also specify a second date—one year later (unless indicated otherwise)—which applies to first registration (entry into service) of existing, previously type-approved vehicle models.

Table 1
EU Emission Standards for Passenger Cars (Category M1*), g/km
Tier Date COHCHC+NOxNOxPM
Diesel
Euro 1† 1992.07 2.72 (3.16)-0.97 (1.13)-0.14 (0.18)
Euro 2, IDI 1996.01 1.0-0.7-0.08
Euro 2, DI 1996.01a 1.0-0.9-0.10
Euro 3 2000.01 0.64-0.560.500.05
Euro 4 2005.01 0.50-0.300.250.025
Euro 5 2009.09b 0.50-0.230.180.005e
Euro 6 2014.09 0.50-0.170.080.005e
Petrol (Gasoline)
Euro 1† 1992.07 2.72 (3.16)-0.97 (1.13)--
Euro 2 1996.01 2.2-0.5--
Euro 3 2000.01 2.300.20-0.15-
Euro 4 2005.01 1.00.10-0.08-
Euro 5 2009.09b 1.00.10c-0.060.005d,e
Euro 6 2014.09 1.00.10c-0.060.005d,e
* At the Euro 1..4 stages, passenger vehicles > 2,500 kg were type approved as Category N1 vehicles
† Values in brackets are conformity of production (COP) limits
a - until 1999.09.30 (after that date DI engines must meet the IDI limits)
b - 2011.01 for all models
c - and NMHC = 0.068 g/km
d - applicable only to vehicles using DI engines
e - proposed to be changed to 0.003 g/km using the PMP measurement procedure
Table 2
EU Emission Standards for Light Commercial Vehicles, g/km
Category† Tier Date COHCHC+NOxNOxPM
Diesel
N1, Class I
≤1305 kg
Euro 1 1994.10 2.72-0.97-0.14
Euro 2, IDI 1998.01 1.0-0.70-0.08
Euro 2, DI 1998.01a 1.0-0.90-0.10
Euro 3 2000.01 0.64-0.560.500.05
Euro 4 2005.01 0.50-0.300.250.025
Euro 5 2009.09b 0.50-0.230.180.005e
Euro 6 2014.09 0.50-0.170.080.005e
N1, Class II
1305-1760 kg
Euro 1 1994.10 5.17-1.40-0.19
Euro 2, IDI 1998.01 1.25-1.0-0.12
Euro 2, DI 1998.01a 1.25-1.30-0.14
Euro 3 2001.01 0.80-0.720.650.07
Euro 4 2006.01 0.63-0.390.330.04
Euro 5 2010.09c 0.63-0.2950.2350.005e
Euro 6 2015.09 0.63-0.1950.1050.005e
N1, Class III
>1760 kg
Euro 1 1994.10 6.90-1.70-0.25
Euro 2, IDI 1998.01 1.5-1.20-0.17
Euro 2, DI 1998.01a 1.5-1.60-0.20
Euro 3 2001.01 0.95-0.860.780.10
Euro 4 2006.01 0.74-0.460.390.06
Euro 5 2010.09c 0.74-0.3500.2800.005e
Euro 6 2015.09 0.74-0.2150.1250.005e
Petrol (Gasoline)
N1, Class I
≤1305 kg
Euro 1 1994.10 2.72-0.97--
Euro 2 1998.01 2.2-0.50--
Euro 3 2000.01 2.30.20-0.15-
Euro 4 2005.01 1.00.1-0.08-
Euro 5 2009.09b 1.00.10f-0.060.005d,e
Euro 6 2014.09 1.00.10f-0.060.005d,e
N1, Class II
1305-1760 kg
Euro 1 1994.10 5.17-1.40--
Euro 2 1998.01 4.0-0.65--
Euro 3 2001.01 4.170.25-0.18-
Euro 4 2006.01 1.810.13-0.10-
Euro 5 2010.09c 1.810.13g-0.0750.005d,e
Euro 6 2015.09 1.810.13g-0.0750.005d,e
N1, Class III
>1760 kg
Euro 1 1994.10 6.90-1.70--
Euro 2 1998.01 5.0-0.80--
Euro 3 2001.01 5.220.29-0.21-
Euro 4 2006.01 2.270.16-0.11-
Euro 5 2010.09c 2.270.16h-0.0820.005d,e
Euro 6 2015.09 2.270.16h-0.0820.005d,e
† For Euro 1/2 the Category N1 reference mass classes were Class I ≤ 1250 kg, Class II 1250-1700 kg, Class III > 1700 kg.
a - until 1999.09.30 (after that date DI engines must meet the IDI limits)
b - 2011.01 for all models
c - 2012.01 for all models
d - applicable only to vehicles using DI engines
e - proposed to be changed to 0.003 g/km using the PMP measurement procedure
f - and NMHC = 0.068 g/km
g - and NMHC = 0.090 g/km
h - and NMHC = 0.108 g/km

Particle Number Emissions. Under the draft implementing legislation, a particle number emission limit of 5 × 1011 km-1 (PMP method, NEDC test) becomes effective at the Euro 5/6 stage for all categories of diesel vehicles (M, N1, N2). The particle number limit must be met in addition to the PM mass emission limits listed in the above tables.

The particle number emission limit is not applicable to gasoline vehicles.

Durability. Useful vehicle life for the purpose of emission regulations is:

Other Provisions. The regulations include several additional provisions, such as:

OBD Requirements

Starting from the Euro 3 stage, vehicles must be equipped with an onboard diagnostic system for emission control. Driver must be notified in case of a malfunction or deterioration of the emission system that would cause emissions to exceed mandatory thresholds, as listed in Table 3 (Euro 4 limits are proposed). The thresholds are based on the NEDC (cold start ECE+EUDC) test. To distinguish from the US OBD, the European limits are also referred to as the EOBD (European OBD).

Table 3
European OBD Threshold Limits, g/km
Category Class Tier Date CO HC NOx PM
Diesel
M1   EU 3 2003 3.20 0.40 1.20 0.18
EU 4 2005 3.20 0.40 1.20 0.18
N1 I EU 3 2005 3.20 0.40 1.20 0.18
EU 4 2005 3.20 0.40 1.20 0.18
II EU 3 2006 4.00 0.50 1.60 0.23
EU 4 2006 4.00 0.50 1.60 0.23
III EU 3 2006 4.80 0.60 1.90 0.28
EU 4 2006 4.80 0.60 1.90 0.28
Petrol (Gasoline)
M1   EU 3 2000 3.20 0.40 0.60 -
EU 4 2005 1.90 0.30 0.53 -
N1 I EU 3 2000 3.20 0.40 0.60 -
EU 4 2005 1.90 0.30 0.53 -
II EU 3 2001 5.80 0.50 0.70 -
EU 4 2005 3.44 0.38 0.62 -
III EU 3 2001 7.30 0.60 0.80 -
EU 4 2005 4.35 0.47 0.70 -
Note: Passenger cars category M1 > 2,500 kg or with more than 6 seats meet OBD requirements for Category N1.

A number of OBD issues were clarified in the Directive 1999/102/EC. Dates of OBD application to gas fueled (LPG or NG) vehicles are given in Directive 2001/1/EC.