Division 2.4.14 Exhaust after-treatment systems

The function and combination of the following devices are regarded as membership criteria for an engine family:

1. (a)

   Oxidation catalyst;

2. (b)

   DeNO_x system with selective reduction of NO_x (addition of reducing agent);

3. (c)

   Other DeNO_x systems;

4. (d)

   Particulate after-treatment system with passive regeneration:

   1. (1)

      wall-flow,

   2. (2)

      non-wall-flow;

5. (e)

   Particulate after-treatment system with active regeneration:

   1. (1)

      wall-flow,

   2. (2)

      non-wall-flow;

6. (f)

   Other particulate after-treatment systems;

7. (g)

   Other devices.

When an engine has been certified without exhaust after-treatment system, whether as parent engine or as member of the engine family, then this engine, when equipped with an oxidation catalyst (not with particulate after-treatment system), may be included in the same engine family, if it does not require different fuel characteristics.

If it requires specific fuel characteristics (e.g. particulate after-treatment systems requiring special additives in the fuel to ensure the regeneration process), the decision to include it in the same engine family shall be based on technical elements provided by the manufacturer. These elements shall indicate that the expected emissions level of the equipped engine complies with the same limit value as the non-equipped engine.

When an engine has been certified with exhaust after-treatment system, whether as parent engine or as member of an engine family, whose parent engine is equipped with the same exhaust after-treatment system, then this engine, when equipped without exhaust after-treatment system, shall not be added to the same engine family.