A wind tunnel test of newly developed personal bioaerosol samplers

In this study, the performance of two newly developed personal bioaerosol samplers was evaluated. The two test samplers are cyclone-based personal samplers that incorporate a recirculating liquid film. The performance evaluations focused on the physical efficiencies that a personal bioaerosol sampler could provide, including aspiration, collection, and capture efficiencies. The evaluation tests were carried out in a wind tunnel, and the test personal samplers were mounted on the chest of a full-size manikin placed in the test chamber of the wind tunnel. Monodisperse fluorescent aerosols ranging from 0.5 to 20 mu m were used to challenge the samplers. Two wind speeds of 0.5 and 2.0 m/sec were employed as the test wind speeds in this study. The test results indicated that the aspiration efficiency of the two test samplers closely agreed with the ACGIH inhalable convention within the size range of the test aerosols. The aspiration efficiency was found to be independent of the sampling orientation. The collection efficiency acquired from these two samplers showed that the 50% cutoff diameters were both around 0.6 mu m. However, the wall loss of these two test samplers increased as the aerosol size increased, and the wall loss of PAS-4 was considerably higher than that of PAS-5, especially in the aerosol size larger than 5 mm, which resulted in PAS-4 having a relatively lower capture efficiency than PAS-5. Overall, the PAS-5 is considered a better personal bioaerosol sampler than the PAS-4. Implications: Detection of personal exposure to airborne microorganisms (bioaerosols) is essential for developing adequate environmental and occupational air monitoring programs. Recently, two liquid-cyclone-based personal bioaerosol samplers were developed for this purpose. This study is to evaluate the performance of these two newly developed samplers in terms of their physical sampling efficiencies, such as the aspiration, collection, and capture efficiencies. The results acquired can offer insight into the efficacy of the newly designed samplers on achieving the goal of providing reliable and accurate personal bioaerosol exposure assessment.