Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Comparison of airborne asbestos levels determined by transmission electron microscopy (TEM) using direct and indirect transfer techniques : final report /
Author Chesson, J. ; Hatfield, J.
CORP Author Chesson Consulting, Washington, DC. ;Battelle, Arlington, VA.;Environmental Protection Agency, Washington, DC. Office of Toxic Substances.
Publisher Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency,
Year Published 1992
Report Number EPA-68-02-4294; EPA/560/5-89/004
Stock Number PB92-191113
OCLC Number 45896487
Subjects Asbestos dust--Measurement. ; Transmission electron microscopes.
Additional Subjects Asbestos ; Air pollution detection ; Transmission electron microscopy ; Indoor air pollution ; School buildings ; Air pollution monitoring ; Occupational safety and health ; Air pollution abatement ; Comparison ; Reliability
Internet Access
Description Access URL
Library Call Number Additional Info Location Last
NTIS  PB92-191113 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 01/01/1988
Collation xii, 56 pages : illustrations ; 28 cm
A subset of air samples from a 1988 EPA study was reanalyzed for asbestos by TEM using an indirect transfer technique. The samples were originally analyzed using a direct transfer technique. The document presents the results of the reanalysis and extends the discussion to include data from six other studies. The development of the two techniques and their respective advantages and disadvantages are described. The data support the general opinion that TEM analysis of air samples using indirect transfer methods tends to provide estimates of total airborne asbestos structure concentration that are higher than those obtained using direct transfer methods. There is no single factor that can be used to convert measurements made by one method to a value that is comparable with measurements made by the other because the quantitative relationship is expected to depend on details of the sampling and analytical protocols and the nature of the asbestos in the air. The ratio of indirect measurements to direct measurements ranges from 3.8 to 1,700 for the studies considered. Additional research is needed to determine which transfer technique more accurately reflects biologically meaningful airborne asbestos concentrations. Breakdown of larger structures into smaller ones during indirect preparation does not appear to be sufficient to explain the difference in measured concentrations.
Spine title: Transmission electron microscopy using direct and indirect techiques. "EPA 560/5-89-004." "March 1990." Microfiche.