AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Using Virtual Impactor for Classification of Submicron-Sized Indoor Bioaerosols
ALI MOHAMADI NASRABADI, Ji-Woon Park, Hyung Sun Kim, Jang-Seop Han, Junho Hyun, Dongeun Yong, Jungho Hwang, Yonsei University, Department of Mechanical Engineering
Abstract Number: 32 Working Group: Indoor Aerosols
Abstract Airborne fungal and bacterial particles (i.e., bioaerosols) can penetrate deep into the lower respiratory tract and deposit in the bronchi, bronchioles, and alveoli, particularly when inhaled by infants. This study aimed to sample and classify indoor bioaerosols using a virtual impactor with a cutoff diameter of 1 μm, which was designed and fabricated. To design the virtual impactor, a computational fluid dynamics simulation was conducted to determine its optimal design and predict its performance. Using polystyrene latex particles, laboratory tests were conducted to evaluate performance and validate simulation results. By changing the inlet flow rate and minor-to-total flow ratio, cutoff diameters of 635 nm and 1.5 µm were obtained. Using an SKC Button Aerosol Sampler at the virtual impactor outlets, field test results demonstrated that 56% of fungal fragments and 63% of bacterial particles that were suspended in an office environment had aerodynamic sizes that were smaller than 1 µm. Furthermore, Our results from MALDI-TOF analysis showed that nearly the same bacterial species were found in the major and minor outlet channels, with gram-positive bacteria being dominant in all samples.