AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Real-Time Measurements of Fluorescent Biological Aerosol Particles in the Infant Near-Floor Microenvironment in a Child Development Laboratory School
TIANREN WU, Brandon E. Boor, Purdue University
Abstract Number: 627 Working Group: Indoor Aerosols
Abstract Infants and young children spend a considerable amount of their time (~8 hours/day) in childcare facilities. Crawling, playing, walking, movements in a crib, and other activities can induce resuspension of settled dust, a process that can contribute to early-life inhalation exposures to bacteria, fungi, pollen, and allergens. Infants can be exposed to bioaerosols they themselves resuspend, as well as particles resuspended by other infants and adults, the shedding of skin, and the transport of outdoor bioaerosols indoors via ventilation and infiltration. The objective of this study is to characterize the size distribution and concentration of fluorescent biological aerosol particles (FBAPs) in the infant near-floor microenvironment in field conditions.
Measurements were conducted in the Purple Room at the Ben and Maxine Miller Child Development Laboratory School at Purdue University. Infants in the Purple Room are 6 weeks to 2 years in age (enrollment=8) and are supervised by two teachers and a child care aid. The room is mechanically ventilated and flooring materials consist of carpet and hard tile, which are cleaned daily. A laser-induced fluorescence-based instrument, the Wideband Integrated Bioaerosol Sensor (WIBS-NEO, Droplet Measurement Technology), sampled at infant breathing zone height (50 cm) with copper tubing in an air-cooled, foam-lined plastic box designed to muffle the noise of the pump and maintain security of the infants. Total particle and FBAP size distributions (0.5 to 30 μm) were monitored continuously during occupied (7:30-17:30, M-F) and unoccupied periods for several weeks. We will present preliminary results categorizing the mean number concentration of FBAPs per event, such as free play, group time, lunch, clean-up, and quiet/nap time, to better understand the dynamic nature of infant bioaerosol exposures in childcare facilities. The transient behavior of FBAPs in the infant breathing zone will be related to the spatial proximity of infants and teachers to the WIBS, as monitored via an observation room.