Determination of the Filter Efficiency of High Volume Air Condition (hvac) Systems of Different Cars with Real Particle Pollution Systems in Peking

Fine particulate matter und ultrafine particles can be harmful to human health in different ways. Therefore, in new cars the attempt is made, to prohibit the in-cabin room from fine particulate matter and ultrafine particles, which may be present in the outside air. Within this study it has been investigated, if the High Volume Air Condition (HVAC) systems of cars can quantitatively purify the outside air when entering the cars. Various cars from different car manufacturers and in different classes (car segments) have been analyzed within this study. Throughout these investigations the HVAC systems of the cars have been tested while driving or while standing still in the highly polluted air of Peking. In this paper the measurement instruments as well as the test procedures are described. During the tests some cars showed very good results for the in-car filtering. However, it could be demonstrated that not all the cars of different manufacturers had the same good filter efficiency. Generally this study proved better air cleaning by the HVAC systems during recirculating air operation than by directly using outside air for the intake of the HVAC systems.