Size-Resolved Penetration Through High-Efficiency Filter Media Typically Used for Aerosol Sampling

Abstract

We have developed a new, fully controlled filter testing device and have used it to measure size-resolved penetration through a typically used filtration media for (but not only) atmospheric aerosol sampling. Twenty membrane and fiber filter pieces (mixed cellulose ester filters, polytetrafluoroethylene filters, quartz fiber filters, glass fiber filters, and polycarbonate filters) of various manufacturers and filter codes were examined. High variability in the penetration curve shapes, most penetrating particle size (MPPS) (from 20 nm to 90 nm) and penetration maxima (from 0.001% to almost 100%) has been found. The dependence of pressure drop on face velocity generally agrees with theory, the comparison of penetration at various face velocities proved the theoretical equations being able to determine MPPS only partially correctly. Although the variability within an individual filter of the same code is not negligible, it is small compared to the differences between the various filter types. The results not only differed from the information provided by the manufacturers, but in many cases also provided information otherwise unavailable, although affecting the sampling and also the ability of comparison with theory. To have enough information for the proper choice of the filter for a given purpose, it would be necessary to have not only total penetration given from the DOP standard measurement, but the MPPS, penetration maximum value and pressure drop as well.

Copyright 2015 American Association for Aerosol Research

ACKNOWLEDGMENTS

The authors thank Mr. Sean Miller for his language corrections of the manuscript.

SUPPLEMENTAL MATERIAL

Supplemental data for this article can be accessed on the publisher's website.

Funding

This work was supported by the Ministry of Interior of the CR under grant No. VF2010201513 (J. Ondráček) and by the Czech Science Foundation under grant CSF P503/12/G147 (N. Zíková). The authors would like to thank also Professor R. Holub from Clarkson University for the long-term loan of one UCPC, Š. Rychlík from the Czech Hydrometeorological Institute for providing some of the filter media, and H. Šnajdaufová from the ICPF for the high-pressure mercury porosimetry measurement.