Assessment of aloe vera for qualitative fit testing of particulaterespirators: a logistic regression approach

摘要

Fit testing procedure is required for filtering facepiece respirators (FFRs) to ascertainan acceptable fit between the skin and facepiece sealing surface. The present study seeksto compare the efficacy of Aloe vera (A. vera) and commercial Bitrex aschallenge agents of qualitative fit testing of particulate respirators. An herbal solutionconsisting of A. vera at seven different concentrations was developed. Threshold ScreeningTests (TSTs) of A. vera solutions were compared to Bitrex . To do so,solutions were administered randomly on a total of 62 participants. A placebo was alsotested to ensure the taste response being valid. Statistical analysis was performed usingR 3.2.5.0 software. There were no statistically significant differences between the A.vera (41.7, 58.3, 75, and 91.7 mg/ml) and Bitrex threshold tests. Therefore,the minimum concentration of A. vera to develop the threshold solution was considered tobe 41.7 mg/ml. When commercial products are expensive and unavailable, a cost-effectivetechnique would be to replace A. vera solution with a commercial product as a challengeagent of qualitative fit testing of respirators.