Comparison of filtration performance of commercially available automotive cabin air filters against various airborne pollutants

Controlling air pollutants in the automobile cabin environment has become increasingly important owing to the health risks of exposure to high concentrations of harmful air pollutants. To protect daily commuters and drivers against the harmful effects of air pollution, modern automobiles are commonly equipped with automotive cabin air filters (ACAFs). Thus, understanding the filtration performance of ACAFs is essential for assessing cabin indoor air quality. In this study, six original equipment manufacturer (OEM) and nine after-market ACAFs were selected and their particulate matter (PM) filtration performance against standard particle (ISO 12103-1 A2 dust), filter pressure drop under various airflow velocities, and gas removal performance against standard test gases (n-butane and toluene) were estimated. In the PM filtration test, the lowest filtration performance occurred at a particle size range of 0.3-0.5 mu m, with a filtration efficiency of 50-90%, and the filtration performance increased with increasing particle size. The PM filtration performance of OEM ACAFs (72.3 +/- 13.81%) was higher than that of after-market ACAFs (56.4 +/- 23.72%). All test OEM ACAFs satisfied the Korea Air Cleaning Association standard filtration performance guidelines for 0.3-0.5-mu m particles ( > 50%), but four of the nine after-market ACAFs did not satisfy the standard guidelines. In addition, only one of the six OEM ACAFs simultaneously satisfied the standard removal performance guidelines for n-butane ( > 70% after 1 min and > 45% after 5 min) and toluene ( > 80% after 1 min and > 70% after 5 min). This study provides valuable baseline information on ACAFs for understanding and improving cabin indoor air quality.