Individual Protection Testing (Task 5 - Qualitative Fit Test Simulants)

Abstract

Abstract : A group of potential replacement qualitative fit test simulants was examined for their effectiveness and compared against the currently used compound, isoamyl acetate (IAA) or banana oil. The literature on odorant compounds was assessed to identify compounds which might be useful, and the toxicological literature was used to screen those for safe compounds. A set of four compounds: nonanoic acid, skatole, t-butyl mercaptan, and methyl salicylate was chosen for odor threshold measurement, along with IAA. Th odor threshold measurements were made using a panel of volunteers and a novel odor presentation technique in a forced-choice triangle, ascending odor design. The results of that testing eliminated nonanoic acid and methyl salicylate from further consideration. Simultaneous qualitative and quantitative fit testing was performed on a panel of subjects using each of the odorants: IAA, t-butyl mercaptan, and skatole. The test results were as consistent as can be expected when using a panel to detect odors. The data obtained indicate that t-butyl mercaptan could be used as a qualitative fit test challenge to achieve mask protection factors significantly higher than those achievable with IAA. Keywords: Chemical agent simulants; Respirator fit testing; Odorants; Qualitative fit testing.