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Using CO2 to Determine Inhaled Contaminant Volumes and Blower Effectiveness in Several Types of Respirators
Joint Authors
Koh, Frank C.
Johnson, Arthur T.
Rehak, Timothy E.
Scott, William H.
Source
Journal of Environmental and Public Health
Issue
Vol. 2011, Issue 2011 (31 Dec. 2011), pp.1-9, 9 p.
Publisher
Hindawi Publishing Corporation
Publication Date
2011-07-18
Country of Publication
Egypt
No. of Pages
9
Main Subjects
Abstract EN
This experiment was conducted to determine how much contaminant could be expected to be inhaled when overbreathing several different types of respirators.
These included several tight-fitting and loose-fitting powered air-purifying respirators (PAPRs) and one air-purifying respirator (APR).
CO2 was used as a tracer gas in the ambient air, and several loose-and tight-fitting respirators were tested on the head form of a breathing machine.
CO2 concentration in the exhaled breath was monitored as well as CO2 concentration in the ambient air.
This concentration ratio was able to give a measurement of protection factor, not for the respirator necessarily, but for the wearer.
Flow rates in the filter/blower inlet and breathing machine outlet were also monitored, so blower effectiveness (defined as the blower contribution to inhaled air) could also be determined.
Wearer protection factors were found to range from 1.1 for the Racal AirMate loose-fitting PAPR to infinity for the 3M Hood, 3M Breath-Easy PAPR, and SE 400 breath-responsive PAPR.
Inhaled contaminant volumes depended on tidal volume but ranged from 2.02 L to 0 L for the same respirators, respectively.
Blower effectiveness was about 1.0 for tight-fitting APRs, 0.18 for the Racal, and greater than 1.0 for two of the loose-fitting PAPRs.
With blower effectiveness greater than 1.0, some blower flow during the exhalation phase contributes to the subsequent inhalation.
Results from this experiment point to different ways to measure respirator efficacy.
American Psychological Association (APA)
Johnson, Arthur T.& Koh, Frank C.& Scott, William H.& Rehak, Timothy E.. 2011. Using CO2 to Determine Inhaled Contaminant Volumes and Blower Effectiveness in Several Types of Respirators. Journal of Environmental and Public Health،Vol. 2011, no. 2011, pp.1-9.
https://search.emarefa.net/detail/BIM-469173
Modern Language Association (MLA)
Johnson, Arthur T.…[et al.]. Using CO2 to Determine Inhaled Contaminant Volumes and Blower Effectiveness in Several Types of Respirators. Journal of Environmental and Public Health No. 2011 (2011), pp.1-9.
https://search.emarefa.net/detail/BIM-469173
American Medical Association (AMA)
Johnson, Arthur T.& Koh, Frank C.& Scott, William H.& Rehak, Timothy E.. Using CO2 to Determine Inhaled Contaminant Volumes and Blower Effectiveness in Several Types of Respirators. Journal of Environmental and Public Health. 2011. Vol. 2011, no. 2011, pp.1-9.
https://search.emarefa.net/detail/BIM-469173
Data Type
Journal Articles
Language
English
Notes
Includes bibliographical references
Record ID
BIM-469173