Exposure profile effects on quantitative fit-factor assessment.
Dalamagas D; Coffey C; Zhuang Z
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida. Fairfax, VA: American Industrial Hygiene Association, 2000 May; :86
The purpose of this study was to correlate quantitative fit-factors to specific exposures by measuring Freon-113 in a wearer's exhaled breath. This was done by determining whether identical exposures, occurring at different times during a 30-minute simulated workplace test (SWPT), would result in different end-exhaled air concentrations (EACs) of Freon-113. The study consisted of three phases, each with four different subjects. End-exhaled air samples were collected 30 minutes after the SWPT and analyzed by gas chromatography. The first phase consisted of four exposure scenarios: 1) 500 ppm during the first minute of the SWPT; 2) 500 ppm during the last minute of the SWPT; 3) 33 ppm during the first 15 minutes of the SWPT; and 4) 33 ppm during the last 15 minutes of the SWPT. The second phase consisted of 1) 500 ppm during , the first six minutes of the SWPT; and 2) 500 ppm during the last six minutes of the SWPT. The third phase consisted of 1) 500 ppm during the first two minutes, between 15 and 16 minutes, and between 28 and 30 minutes of the SWPT; and 2) continuous exposure of 100 ppm during the entire SWPT. No significant difference was found between the means for these scenarios except that the means of scenario 2 of phase 1 was higher for two subjects. A significance level of 0.05 was used for all analyses. It was concluded that exposures of the same magnitude produced the same EACs regardless of when they occurred. Freon-113 EAC can be used to determine the actual level of protection provided by an air-purifying respirator.
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; Humans
American Industrial Hygiene Conference and Exposition, May 20-25, 2000, Orlando, Florida