Soot, Dust: Solids contain in exhaust gases of diesel engines burning heavy fuel not only consist
of soot (carbon) resulting due to incomplete combustion of the fuel but also due to dust and ash particles
from the fuel and the lube oil, the quality of the combustion air and from the abrasion products. Even
though, these constitutes the major source of visible dark coloration, of exhaust gases, soot particles
only account for a relatively low percentage of total dust concentration. Based on the ash content of the
fuel and the lube, the soot quantity also varies as shown in the table below.