Skip directly to search Skip directly to A to Z list Skip directly to page options Skip directly to site content

NIOSHTIC-2 Publications Search

Search Results

Physical collection efficiency of filter materials for bacteria and viruses.

Authors
Burton-NC; Grinshpun-SA; Reponen-T
Source
Ann Occup Hyg 2007 Mar; 51(2):143-151
NIOSHTIC No.
20031712
Abstract
The purpose of this study was to determine the physical collection efficiency of commercially available filters for collecting airborne bacteria, viruses, and other particles in the 10-900 nm (nanometer) size range. Laboratory experiments with various polytetrafluoroethylene (PTFE), polycarbonate (PC) and gelatin filters in conjunction with ButtonTM Inhalable samplers and three-piece cassettes were undertaken. Both biological and non-biological test aerosols were used: Bacillus atrophaeus, MS2, polystyrene latex (PSL), and sodium chloride (NaCl). The B.atrophaeus endospores had an aerodynamic diameter of 900 nm, whereas MS2 virion particles ranged from 10 to 80 nm. Monodisperse 350 nm PSL particles were used as this size was believed to have the lowest filtration efficiency. NaCl solution (1% weight by volume) was used to create a polydisperse aerosol in the 10-600 nm range. The physical collection efficiency was determined by measuring particle concentrations size-selectively upstream and downstream of the filters. The PTFE and gelatin filters showed excellent collection efficiency (>93%) for all of the test particles. The PC filters showed lower collection efficiency for small particles especially <100 nm. Among the tested filters, the lowest collection efficiencies, 49 and 22%, were observed for 1 and 3-Ám pore size PC filters at the particle sizes of 47 and 63 nm, respectively. The results indicate that the effect of filter material is more significant for the size range of single virions than for bacteria. The effect of filter loading was examined by exposing filters to mixtures of PSL particles, which aimed at mimicking typical indoor dust levels and size distributions. A 4-h loading did not cause significant change in the physical collection efficiency of the tested filters.
Keywords
Filter-materials; Air-filters; Air-samplers; Air-sampling-equipment; Aerosol-particles; Filtration; Laboratory-testing; Particle-aerodynamics; Testing-equipment; Styrenes; Sodium-compounds
Contact
National Institute for Occupational Safety and Health, Division of Surveillance, Harzard Evaluations and Field Studies, MS R-11, 4676 Columbia Parkway, Cincinnati, OH, 45226
CODEN
AOHYA3
CAS No.
764-71-4; 9003-53-6
Publication Date
20070301
Document Type
Journal Article
Email Address
NBurton@cdc.gov
Fiscal Year
2007
NTIS Accession No.
NTIS Price
Issue of Publication
2
ISSN
0003-4878
NIOSH Division
DSHEFS
Source Name
Annals of Occupational Hygiene
State
OH
TOP