Studies correlate air pollution with an increase in the incidence of respiratory
diseases, affecting lung function and raising hospitalization rates. Among the
pollutants associated with these diseases, inhalable coarse particulate matter
(PM10) and fine particulate matter (PM2.5) stand out.
The emission of particulate matter resulting from the wear of brake pads in
light vehicles is the second largest source, accounting for approximately 33% of
a vehicle’s total emissions. The particulate matter generated during the braking
process can be analyzed through its collection in tests conducted on
dynamometers, using enclosure and sampling systems. The development of the
dynamometer used was based on the braking cycles described in the SAE J2522:2003
standard, whose main objective is to provide comparative data on different
friction materials. Given the variations in particulate matter emissions
depending on the composition of the brake pads, as reported in the literature,
this study presents an analysis of the emissions from two distinct formulations,
as well as a comparison of wear parameters and the surface roughness of the
pads. The characterization of the particulate matter was carried out using a
sampling system in accordance with ISO 9096:2017, with a sampling duct aligned
with the flow duct downstream of the enclosure chamber, and particle retention
achieved through fiberglass filters. The airflow velocity was controlled to
ensure isokinetic transport conditions in the sampling system, adjusting the
connected pump to match the probe velocity. The results show that wear was not
uniform between the pairs of brake pads, also revealing differences in the
chemical composition of the particulate matter according to the different
formulations, consistent with what is reported in the literature, but with
similar particle concentrations by size.