At the time of going to press emission standard IV applies in Europe.
In the diesel sector, emission standard IV is achieved using two different methods.
One method consists of reducing exhaust emissions by means of internal engine measures to the extent that the prescribed limit values are met.
Measures for the reduction of exhaust emissions inside the engine include, for example:
โข further optimized exhaust gas recirculation by means of an electrically controlled EGR system with intake air restriction,
โข optimization of the combustion chamber design and the injection characteristics.
In addition to optimization through internal engine measures, the second method employs a diesel particulate filter system.
With the use of diesel particulate filters, diesel particulate emissions are reduced by more than 99%. This reduction far exceeds the requirements for the European emission limits of emission standard IV.
It can therefore be assumed that the use of the diesel particulate filter will be of great importance with regard to future emission standards, but is not absolutely necessary for meeting emission standard IV.