Document Detail

Parameters that bias the measurement of airborne concentration within a respirator.
MedLine Citation:
PMID:  3456696     Owner:  NLM     Status:  MEDLINE    
This paper describes the theoretical basis upon which a test system has been set up to evaluate the sampling error associated with in-facepiece sampling on half-mask respirators. The in-facepiece sampling technique evaluated in this study is the one currently used in the U.S. to conduct quantitative facepiece fit testing. An experimental design was developed to study the sampling bias associated with in-facepiece sampling when selected parameters of the man/respirator system were varied. The results indicated that significant errors can be made in estimating concentration within a respirator when the current in-facepiece sampling technique is employed. Sampling bias was determined when in-facepiece samples were collected only during the inhalation phase of the respiratory cycles. They were found to range from greater than -99% to greater than +98%. The mean sampling bias was -17 +/- 38%. When measured in-facepiece concentrations were used to calculate a fit factor the resulting range was 44 to 4728 even though the actual fit factor was only 87. Based upon the data presented, it was hypothesized that faceseal leakage was streamlining within the respirator cavity. As a result, quantitative facepiece fit data on half-mask respirators may be biased by the large measurement error.
W R Myers; J Allender; R Plummer; T Stobbe
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Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, Non-P.H.S.    
Journal Detail:
Title:  American Industrial Hygiene Association journal     Volume:  47     ISSN:  0002-8894     ISO Abbreviation:  Am Ind Hyg Assoc J     Publication Date:  1986 Feb 
Date Detail:
Created Date:  1986-04-17     Completed Date:  1986-04-17     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0371160     Medline TA:  Am Ind Hyg Assoc J     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  106-14     Citation Subset:  IM    
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MeSH Terms
Acetone / analysis
Air / analysis*
Air Pollutants / analysis
Models, Biological
Quality Control
Ventilators, Mechanical / standards*
Reg. No./Substance:
0/Aerosols; 0/Air Pollutants; 67-64-1/Acetone

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

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