# Commission Regulation (EC) No 692/2008 of 18 July 2008 implementing and amending Regulation (EC) No 715/2007 of the European Parliament and of the Council on type-approval of motor vehicles with respect to emissions from light passenger and commercial vehicles (Euro 5 and Euro 6) and on access to vehicle repair and maintenance information (Text with EEA relevance), Division 2.4: Parameters defining the tailpipe emissions in-service family

Extent: E+W+S+N.I.

The in-service family may be defined by basic design parameters which shall be common to vehicles within the family. Accordingly, vehicle types may be considered as belonging to the same in-service family if they have in common, or within the stated tolerances, the following parameters:
2.4.1. combustion process (two stroke, four stroke, rotary);
2.4.2. number of cylinders;
2.4.3. configuration of the cylinder block (in-line, V, radial, horizontally opposed, other. The inclination or orientation of the cylinders is not a criteria);
2.4.4. method of engine fuelling (e.g. indirect or direct injection);
2.4.5. type of cooling system (air, water, oil);
2.4.6. method of aspiration (naturally aspirated, pressure charged);
2.4.7. fuel for which the engine is designed (petrol, diesel, NG, LPG, etc.). Bi fuelled vehicles may be grouped with dedicated fuel vehicles providing one of the fuels is common;
2.4.8. type of catalytic converter (three-way catalyst, lean NO x trap, SCR, lean NO x catalyst or other(s));
2.4.9. type of particulate trap (with or without);
2.4.10. exhaust gas recirculation (with or without, cooled or non-cooled); and
2.4.11. engine cylinder capacity of the largest engine within the family minus 30 %.

---
Source: https://www.legislation.gov.uk/eur/2008/692/annex/II/division/2/division/2.4 (the official version)
Page: https://openlegislation.uk/eu-regulation-2008-692/annex-II/division-2/division-2.4
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.