What is the difference between gasoline and D2

Emission class: From D2 to Euro 6

In Germany, the vehicle class decides whether a car is assigned a red, yellow or green environmental badge. Since the beginning of 2015, the Euro 6 emissions standard has been binding for all new registrations. This is divided into nine sub-categories that have one thing in common: a maximum CO2 emission of 500 milligrams per kilometer.

German emission standards such as D3 and D4 have merely anticipated the regulations of the Euro emission standards. They are seen as a national extension that was particularly relevant for taxation in Germany. At the moment they are no longer of importance, the Euro emission class is decisive.

Determination of the pollutant classes

Vehicles with internal combustion engines naturally produce exhaust gases. The emission class shows how high a vehicle's emissions are. In the context of emissions standards such as the Euro standard, limit values ​​are set for the emission of carbon monoxide (CO), nitrogen oxides (NOx), Hydrocarbons (HC) and particles (PM).

On the basis of these limit values, vehicles are in turn divided into different classes of pollutants. When defining the limit values, a distinction is made between gasoline and diesel engines. Diesel engines generally emit more pollutants than gasoline engines, so different limit values ​​are required. Furthermore, a distinction is made in the classification into pollutant classes according to vehicle type - i.e. cars, trucks and buses, two-wheelers and mopeds.

The emission class currently to be met and new emissions tests

Emission classes are particularly important for car manufacturers because they are binding for new vehicles. Since September 1, 2015, newly registered vehicles have to meet the Euro 6 standard, previously the less strict Euro 5 standard was sufficient.

Since September 2017 there have been two new emissions tests across the EU: WLTP and RDE. WLTP ("Worldwide Harmonized Light-Duty Vehicles Test Procedure") was the successor to the NEDC ("New European Driving Cycle"), which has been in effect since 1992.

Since September 1, 2018, WLTP tests have been the basis for new cars to be registered. In September 2019, the rules were tightened again: lower tolerances and deviations are only accepted. Currently, under the 6d-TEMP, a car is allowed to emit a maximum of 160 milligrams per kilometer of nitrogen oxides on the road, or 110 percent more in the RDE process than in the WLTP.

In 2020, a further tightening of the Euro norm 6d is planned - then the value will drop to only 120 milligrams or 50 percent more exhaust gases in the RDE than in the WLTP process. Another change that took effect on September 1, 2019: Manufacturers of light commercial vehicles in category N1 (class II and III) and category N2 must now report exhaust gas values ​​in accordance with WLTP.

Overview of pollutant classes for cars

  • Euro 0: non-polluting cars (they are not allowed to drive in case of ozone alarm, for example)
  • Euro 1: highest pollutant emissions, since July 1st, 1992, first registration from January 1st, 1993
  • Euro 2: since January 1st, 1996, first registration from January 1st, 1997
  • Euro 3: since January 1st, 2000, first registration from January 1st, 2001
  • Euro 4: since January 1st, 2005, first registration from January 1st, 2006
  • Euro 5: since September 1st, 2009/2011, first registration from January 1st, 2011
  • Euro 6, divided into:
    • Euro 6a
    • Euro 6b (since 2015, first registration from 01.09.2015)
    • Euro 6c (since September 1, 2017 or September 1, 2018 for all new registrations)
    • Euro 6d-TEMP (valid until the end of 2019)
    • Euro 6d (applies from January 2020) Electric cars have no emission classes.

Trucks and buses from 3.5 tons are vehicle classes in Roman numerals. Here, too, Euro I achieves the highest emissions, while Euro VI produces the least pollutants. If new buses or trucks are registered, Euro VI is the condition. Since 2018, the lower pollutant values ​​prescribed by the Euro 4 standard have also been mandatory for light vehicles such as microcars and mopeds, mopeds, quads and trikes that can be driven from the age of 16 without a license.

Determine the emission class of a vehicle

Emission code number in the registration certificate.

Photo: ADAC / ADAC

The emission class of your car can be found in the registration certificate Part I or, in the case of vehicles registered before October 1, 2005, in the vehicle registration document.

In the registration certificate, part I, you will find the designation of the national emission class under number 14; for older vehicle certificates, an emission group is specified in field 1. In older vehicles, however, this emission standard does not correspond to the currently valid pollutant classes.

The entry "low emission according to E2" or "emission class E2" is not to be equated with the Euro 2 standard, but only corresponds to emission class Euro 1.

Emission code number in the vehicle registration document

However, the emission class according to the applicable Euro standard can then be determined using the vehicle's emission code number.

In the newer registration certificate part 1 you will find the key number in field 14.1, the last 2 digits are relevant. In the old vehicle registration document you will find the entry at the top under "Key number - to 1". The last two digits are also relevant here.

Using this code number, the pollutant classes are assigned as follows:

Key numberEmission class
36NO to 36YOEuro 6
36WO to 36YO (test according to NEDC); 36BA to 36BC (test according to WLTP)Euro 6b
36ZA to 36ZF (test according to NEDC); 36AA to 36AF (test according to WLTP)Euro 6c
36ZG to 36ZI (test according to NEDC); 36AG to 36AI, 36BG to 36BI (test according to WLTP)Euro 6d-TEMP
36ZJ to 36ZL (test according to NEDC); 36AJ to 36AL (test according to WLTP)Euro 6d
35AO to 35MO5 euro
32, 33, 38, 39, 43, 62-70Euro 4
30, 31, 36, 37, 42, 44-61Euro 3
25-29, 34, 35, 40, 41, 49, 71Euro 2
01-04, 09, 11-14, 16, 18, 21, 22, 77Euro 1
00, 05-08, 10, 15, 17, 19, 20, 23, 24, 88other

Electric cars do not emit pollutants such as carbon monoxide that are relevant to the Euro emissions standard, which is why there are currently no pollutant classes for them. However, the situation is different for vehicles with hybrid drive, here the Euro emissions standard applies.

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Effect of the pollutant classes: vehicle tax

The emission class is a decisive factor for calculating the vehicle tax. The amount of the vehicle tax is calculated from the emission class in combination with the type of engine (diesel or gasoline engine) and the displacement.

Overview of pollutant classes & tax rates (per 100 cm or part thereof3 Displacement)

Key numberEmission classTax rate OttoTax rate diesel a)Key numberEmission classTax rate OttoTax rate diesel a)
0025,36 €37,58 €35Euro 2, 5L7,36 €16,05 €
01Euro 115,13 €27,35 €36D3, 5L6,75 €15,44 €
02Euro 115,13 €27,35 €37D3 I, 5L6,75 €15,44 €
0325,36 €37,58 €38D4, 5L6,75 €15,44 €
03 a) b) c) d)Euro 115,13 €27,35 €39D4 I, 5L6,75 €15,44 €
0425,36 €37,58 €40E2, 3L6,75 €15,44 €
04 d)Euro 115,13 €27,35 €41Euro 2, 3L6,75 €15,44 €
0525,36 €37,58 €42D3, 3L6,75 €15,44 €
05 g)25,36 €37,58 €43D4, 3L6,75 €15,44 €
0625,36 €37,58 €44Euro 36,75 €15,44 €
0725,36 €37,58 €45Euro 3, 5L6,75 €15,44 €
0825,36 €37,58 €46Euro 3, 3L6,75 €15,44 €
0925,36 €37,58 €47Euro 3 I.6,75 €15,44 €
09 d)Euro 115,13 €27,35 €48Euro 3 I, 5L6,75 €15,44 €
1025,36 €37,58 €49Euro 3 II7,36 €16,05 €
10 d)21,07 €33,29 €50Euro 3 II, 5L7,36 €16,05 €
11Euro 115,13 €27,35 €51Euro 3 III7,36 €16,05 €
12Euro 115,13 €27,35 €52Euro 3 III, 5L7,36 €16,05 €
13Euro 115,13 €27,35 €53Euro 3 + D46,75 €15,44 €
14Euro 115,13 €27,35 €54Euro 3 + D4, 5L6,75 €15,44 €
1525,36 €37,58 €55Euro 3 + D4, 3L6,75 €15,44 €
15 d)21,07 €33,29 €56Euro 3 I + D4 I.6,75 €15,44 €
16Euro 115,13 €27,35 €57Euro 3 I + D4 I, 5L6,75 €15,44 €
1721,07 €33,29 €58Euro 3 II + D4 I.6,75 €15,44 €
18Euro 115,13 €27,35 €59Euro 3 II + D4 I, 5L6,75 €15,44 €
1921,07 €33,29 €60Euro 3 III + D4 I.6,75 €15,44 €
2021,07 €33,29 €61Euro 3 III + D4 I, 5L6,75 €15,44 €
21Euro 115,13 €27,35 €62Euro 46,75 €15,44 €
22Euro 115,13 €27,35 €63Euro 4, 5L6,75 €15,44 €
2321,07 €33,29 €64Euro 4, 3L6,75 €15,44 €
2421,07 €33,29 €65Euro 4 I.6,75 €15,44 €
25Euro 27,36 €16,05 €66Euro 4 I, 5L6,75 €15,44 €
26Euro 27,36 €16,05 €67Euro 4 II6,75 €15,44 €
27Euro 2 I.7,36 €16,05 €68Euro 4 II, 5L6,75 €15,44 €
28Euro 2 II15,13 €27,35 €69Euro 4 III6,75 €15,44 €
29Euro 2 III15,13 €27,35 €70Euro 4 III, 5L6,75 €15,44 €
30D36,75 €15,44 €71Euro 27,36 €16,05 €
31D3 I6,75 €15,44 €77 f)Euro 115,13 €27,35 €
32D46,75 €15,44 €88 e)25,36 €37,58 €
33D4 I6,75 €15,44 €35A0-35M05 euro6,75 €15,44 €
34E2, 5L15,13 €27,35 €36N0-36Y0Euro 66,75 €15,44 €

As of January 2016, source: ADAC

a)The tax surcharge of 1.20 euros per 100 cm3 Displacement for diesel cars without particulate filters ended on April 1, 2011.
b)With a displacement of more than 2,000 cm3 the vehicle automatically receives the Euro 1 tax rate if the key number 03 was assigned before July 6, 1995.
c)The vehicle has a displacement of 1,400 to 2,000 cm3, it must also be proven by a manufacturer's certificate that the emissions standard complies with the requirements of one of the following directives: Annex XXIII StVZO or RL 70/220 / EEC Annex III A (corresponding to the exhaust gas limit values ​​of Annex XXIII StVZO) or RL 91/441 / EEC.
d)Vehicles with gasoline engines that were equipped with a regulated catalytic converter before July 26, 1995. Proof is the entry in the vehicle registration document under number 5 "Otto / G-Kat" drive type and the number "51" behind it. A corresponding entry under item 33 is also accepted.
e)Vehicles for which the pollutant emissions are not known.
f)Vehicles that first came onto the market before October 1, 1995 and were converted to Euro 1 after January 1, 1996.
G)Only for vehicles that were registered for the first time before October 1, 1986 and were recognized as "conditionally low-pollutant A" before January 1, 1988.

In addition to the vehicle tax calculation, the emission class is also relevant for which particulate matter sticker is assigned to a vehicle. This marking, also known as the environmental badge, is required in numerous cities in order to be allowed to enter the corresponding environmental zones.

Driving bans and restrictions for vehicles with high pollutant emissions do not only exist in Germany, but in numerous EU countries. In Austria, for example, the amount of motorway tolls depends on the emission class of a vehicle. Most of the regulations only apply to vehicles over 7.5 tons. It is gradually forbidden to drive diesel vehicles in particular in major German cities. These regulations were increasingly tightened in 2019.

Inner-city environmental zones, internationally known as Low Emission Zones, or LEZ for short, generally also apply to cars. Environmental badges on vehicles are only required in German, Swedish and Danish environmental zones, for example.

Opportunities to improve the pollutant class

The classification of the pollutant classes of vehicles can in many cases be improved by structural changes. However, it must be considered whether the retrofitting costs are actually worthwhile. You should also keep the expected useful life in mind.

Retrofitting options for vehicles with gasoline engines

  • Catalytic converter retrofitting (G-Kat): For older vehicles that previously had no or an unregulated catalytic converter. Improvement from emission class 00 to Euro 1, partly also possible to Euro 2. Costs from around 700 euros.
  • Upgrade catalyst: For vehicles that are already equipped with a regulated catalytic converter. Primarily interesting if the existing catalytic converter has to be replaced anyway due to its age. Improvement from Euro 1 to Euro 2 or D3. Costs from around 400 euros.
  • Cold run control systems: Ensure that the catalytic converter is activated more quickly during a cold start. Improvement from Euro 1 to Euro 2 or D3 possible. Costs from around 200 euros.

Retrofitting options for diesel vehicles

  • Retrofitting a catalytic converter (Oxy-Kat): For vehicles without a catalytic converter. Improvement from emission class 00 to Euro 1, in individual cases also Euro 2. Costs from approx. 400 Euro.
  • Upgrade catalyst: For vehicles with Oxy-Kat. Primarily of interest if the existing catalytic converter has to be replaced anyway due to its age. Improvement from Euro 1 to Euro 2. Costs from approx. 400 Euro.
  • Soot particle filter retrofitting: Reduces soot emissions by around 40 percent, but not available for all diesel engines. Costs between approx. 650 and 1,500 euros, government funding of 260 euros possible.

To the history of the pollutant classes

For many it came as a surprise, but the idea of ​​setting limit values ​​for vehicle emissions originated in the USA. The country, which is not necessarily known for the greatest environmental awareness, had to contend with massive smog problems in California as early as the early 1960s. This made a binding emission control for road traffic necessary.

The regulations were partially adopted by the EU and were incorporated into the first uniform European exhaust gas regulations, which came into force in 1970. Initially, the regulations only concerned carbon monoxide and hydrocarbon emissions. The emission of nitrogen oxides has only been regulated since 1977.

In 1988, the introduction of limit values ​​for soot particles from diesel engines and the first EU-wide emissions standard for trucks and buses followed. For motorized two-wheelers, Europe-wide emission standards have only been in effect since 1997. The first version of the still valid Euro emissions standard came into force in 1991.

German pollution classes (D-Norm)

In addition to the generally binding Euro emission standards, there are also some German emission standards. These D standards are national extensions that were relevant for tax advantages during their validity period. Basically, the D standards only play a subordinate role.

The differences between the two standards are mainly due to the different measuring methods and measuring points. A vehicle with emission class D3, for example, has similar emissions to a vehicle with emission class Euro 3, but it does not fully comply with the Euro 3 standard. As a rule, vehicles with emission class D3 only correspond to Euro 2. In the case of diesel engines, the measurement methods and thus also the limit values ​​for D3 and Euro 3 as well as for D4 and Euro 4 are identical.

The main difference between D and Euro standards are the respective periods of validity.

35th Ordinance for the Implementation of the Federal Immission Control Act (35th BImSchV)

Legally, exhaust standards in Germany are anchored in the Federal Immission Control Act, the exact implementation is regulated in the 35th Ordinance on Implementation (35th BImSchV). The assignment of vehicles to pollutant groups is regulated in §2:

§ 2 35th BImSchV: Allocation of motor vehicles to pollutant groups

(1) Motor vehicles that are marked with a sticker in accordance with Appendix 1 are exempt from a traffic ban within the meaning of Section 40 (1) of the Federal Immission Control Act, insofar as a related traffic sign provides for this.

(2) Motor vehicles are assigned to pollutant groups 1 to 4, taking into account their pollutant emissions. The detailed allocation of the motor vehicles to the pollutant groups can be found in Appendix 2.

(3) Motor vehicles listed in Appendix 3 are exempt from traffic bans in accordance with Section 40 Paragraph 1 of the Federal Immission Control Act even if they are not marked with a sticker in accordance with Paragraph 1.

Criticism of the previous emission class regulation

Criticism of the existing classification into pollutant classes is primarily due to the measurement method. The pollutant emissions measured in the test procedure do not correspond to the values ​​that are achieved under realistic conditions. For example, no speeds of more than 120 km / h are taken into account in the test simulations and driving under full load is not simulated.

Another point of criticism so far has been the differentiation between gasoline and diesel engines. Failure to take into account the number of particles in gasoline engines is particularly difficult. The fine dust emissions of gasoline engines with direct injection are often many times higher than the limit values ​​that apply to diesel engines. On the other hand, nitrogen oxide emissions are neglected in diesel vehicles, while strict regulations apply to gasoline-powered vehicles.

Changes since 2017

The emission test for the Euro emission standard dates from the 1980s and was considered by experts to be out of date. However, the procedure was updated in September 2017. Since then there has been an improved emissions test on the test bench ("WLTP" for short) and an additional one on the road ("RDE" for short). The aim is to be able to demonstrate pollutant emissions under realistic driving conditions.

The regulations, especially the tolerances, were tightened again in September 2019. The new test cycle also tests at higher speeds and is more dynamic. Special equipment of the vehicle and their aerodynamics as well as the respective weight are taken into greater account in the test cycle - as is the rolling resistance of the tires. This gives drivers the opportunity, depending on the individual equipment of the car, to help change the vehicle's CO2 value.