Evaluation of Filter Media for Particle Number, Surface Area and Mass Penetrations

Skip Navigation
LIN LI1,*, ZHILI ZUO1, DANIEL A. JAPUNTICH2 and DAVID Y.H. PUI1

1 Particle Technology Laboratory, Mechanical Engineering, University of Minnesota, 111 Church Street SE,

Minneapolis, MN 55455, USA

; 2 3M Company Building 201-2E-04,

Saint Paul, MN 55144, USA ? *Author to whom correspondence should be addressed. Tel: +3145182090; e-mail: llin{at}umn.edu Received April 5, 2012. Revision received February 21, 2012. Accepted March 14, 2012. The National Institute for Occupational Safety and Health (NIOSH) developed a standard for respirator certification under 42 CFR Part 84, using a TSI 8130 automated filter tester with photometers. A recent study showed that photometric detection methods may not be sensitive for measuring engineered nanoparticles. Present NIOSH standards for penetration measurement are mass-based; however, the threshold limit value/permissible exposure limit for an engineered nanoparticle worker exposure is not yet clear. There is lack of standardized filter test development for engineered nanoparticles, and development of a simple nanoparticle filter test is indicated. To better understand the filter performance against engineered nanoparticles and correlations among different tests, initial penetration levels of one fiberglass and two electret filter media were measured using a series of polydisperse and monodisperse aerosol test methods at two different laboratories (University of Minnesota Particle Technology Laboratory and 3M Company). Monodisperse aerosol penetrations were measured by a TSI 8160 using NaCl particles from 20 to 300nm. Particle penetration curves and overall penetrations were measured by scanning mobility particle sizer (SMPS), condensation particle counter (CPC), nanoparticle surface area monitor (NSAM), and TSI 8130 at two face velocities and three layer thicknesses. Results showed that reproducible, comparable filtration data were achieved between two laboratories, with proper control of test conditions and calibration procedures. For particle penetration curves, the experimental results of monodisperse testing agreed well with polydisperse SMPS measurements. The most penetrating particle sizes (MPPSs) of electret and fiberglass filter media were ~50 and 160nm, respectively. For overall penetrations, the CPC and NSAM results of polydisperse aerosols were close to the penetration at the corresponding median particle sizes. For each filter type, power–law correlations between the penetrations measured by different instruments show that the NIOSH TSI 8130 test may be used to predict penetrations at the MPPS as well as the CPC and NSAM results with polydisperse aerosols. It is recommended to use dry air (<20 data-blogger-escaped-a="a" data-blogger-escaped-adequate="adequate" data-blogger-escaped-aerosol.="aerosol." data-blogger-escaped-aerosol="aerosol" data-blogger-escaped-air="air" data-blogger-escaped-an="an" data-blogger-escaped-and="and" data-blogger-escaped-as="as" data-blogger-escaped-challenge="challenge" data-blogger-escaped-chloride="chloride" data-blogger-escaped-constant="constant" data-blogger-escaped-cpc="cpc" data-blogger-escaped-deliquescing="deliquescing" data-blogger-escaped-detectors.="detectors." data-blogger-escaped-dielectric="dielectric" data-blogger-escaped-for="for" data-blogger-escaped-fully="fully" data-blogger-escaped-geometric="geometric" data-blogger-escaped-in="in" data-blogger-escaped-is="is" data-blogger-escaped-it="it" data-blogger-escaped-makeup="makeup" data-blogger-escaped-mean="mean" data-blogger-escaped-minimizing="minimizing" data-blogger-escaped-nanoparticle="nanoparticle" data-blogger-escaped-neutralize="neutralize" data-blogger-escaped-neutralizer="neutralizer" data-blogger-escaped-nm="nm" data-blogger-escaped-nsam="nsam" data-blogger-escaped-of="of" data-blogger-escaped-or="or" data-blogger-escaped-particle="particle" data-blogger-escaped-penetration="penetration" data-blogger-escaped-polydisperse="polydisperse" data-blogger-escaped-prevent="prevent" data-blogger-escaped-recommended="recommended" data-blogger-escaped-rh="rh" data-blogger-escaped-simple="simple" data-blogger-escaped-sodium="sodium" data-blogger-escaped-system="system" data-blogger-escaped-test="test" data-blogger-escaped-the="the" data-blogger-escaped-to="to" data-blogger-escaped-use="use" data-blogger-escaped-with="with">Keywords: © The Author 2012. Published by Oxford University Press on behalf of the British Occupational Hygiene SocietyThis ArticleAnn Occup Hyg (2012) 56 (5): 581-594. doi: 10.1093/annhyg/mes034 Current Issue
Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.

View the original article here

Posted in: Evaluation, Filter, Media, Number, Particle, Penetrations, Surface