The devices to reduce particulate matter emission from disc brake and drum brake mechanisms of motor vehicles successfully passed rig tests carried out on laboratory test stands. In this paper, results of testing the devices installed in a passenger car have been presented. The tests were carried out on a vehicle chassis dynamometer in the conditions of special driving tests. The effectiveness of operation of the system under consideration was found to be good: the particulate matter emission was reduced by about 50 to 70%. The examinations have revealed that the brake dusts comprise particles of very small dimensions and that heavy metals are among the major particle components. Results of tests carried out when the test vehicle was driven in real urban traffic confirmed high effectiveness of operation of the system developed. However, the road test results were not as good as the results obtained from the chassis dynamometer tests because of some design problems that emerged at the installation of an autonomous system version in the test vehicle. The experience gained at the road tests is now used for modifying the system to reduce dust emission from motor vehicle brake mechanisms.