Particulate emissions are consequently separated according
to the diameter class. Three categories are distinguished,
namely less than 2.5 micron, between 2.5 and 10 micron,
and more than 10 micron. Therefore, there is no double counting
of particulate emissions. It has to be noted that these classes
do not coincide with the standard measurements which distinguish
between less than 2.5 micron (PM2.5), less than 10
micron (PM10) and total particulate matter (TPM). Furthermore,
the distinction between the three classes is often based
on reference works and not based on actual measurements
performed on exactly the processes analysed.