Comparison of six respirator fittest methods with an actual measurement of exposure using fullfacepiece respirators.
Coffey-C; Zhuang-Z; Lawrence-R; Jensen-P
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida. Fairfax, VA: American Industrial Hygiene Association, 2000 May; :86
A recent study found that some quantitative fittest (QNFT) methods may be predictive of actual half-mask respirator performance. The purpose of this study was to determine whether the same degree of predictability could be found using full-facepiece respirators. Fit-factors from six QNFT methods performed under laboratory conditions were compared with the exposure to 1, 1, 2-trichloro-1, 2, 2-trifluoroethane [Freon-113] assessed by exhaled breath analysis. The six QNFT methods were 1) low flow, flush probe corn oil (CLF); 2) high flow, deep probe corn oil (CHD); 3) controlled negative pressure (CNP); 4) ambient aerosol, 10 minutes, six exercises (AA1); 5) ambient aerosol, 30 minutes, 17 exercises (AA2); and 6) high flow, deep probe ambient aerosol (AAHD). Each method was conducted on a sample of 30 subjects with three replications. Each subject randomly selected 3 of 10 organic vapor/P100 full-facepiece respirators. The exhaled breath of each subject exposed to 500 ppm of Freon-113 was first evaluated at 30 minutes post-exposure. This characterization was then used to estimate the actual exposure to Freon-113 during correlation testing. Fit-factors resulting from the QNFT protocols were then individually correlated with the Freon-113 exposures using the coefficient of determination, R2. Statistically significant correlation between fit-factors and actual exposure doses of Freon-113 was found with some QNFT methods. But the highest R2 value was only 0.20. The correlations were not as strong as those observed with the half-mask respirators in the previous study. The results of this study suggest that some QNFT methods can predict actual performance of full-facepiece respirators.
Personal-protective-equipment; Respirators; Respiratory-equipment; Respiratory-protection; Respiratory-protective-equipment; Breathing; Quantitative-analysis; Exposure-assessment; Equipment-reliability; Materials-testing; Measurement-equipment; Simulation-methods; Workplace-studies; Air-sampling; Air-quality-measurement; Gas-chromatography; Air-purifying-respirators; Ethanes; Face-masks; Laboratory-testing; Air-flow; Aerosols; Air-pressure; Organic-vapors; Humans
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida