Submitted to: American Association for Aerosol Research
Publication Type: Abstract Only
Publication Acceptance Date: 5/1/2007
Publication Date: 9/9/2007
Citation: Purdy, C.W., Clark, R.N., Straus, D.C. 2007. Indoor air quality of four Southern High Plains dairy milking parlors in the summer and winter [abstract]. In: Proceedings of the American Association for Aerosol Research Annual Conference, September 9-14, 2007, Reno, Nevada. p. 3B.4. 2007 CD-ROM.
Technical Abstract: Milking parlor indoor air quality of 4 large dairies was sampled to investigate: (1) bacterial and fungal concentration/m**3 of air, (2) bioaerosol microbial types, and (3) respirable and non-respirable bioaerosol concentrations/m**3 of air. Equipment used were cascade biological samplers, a laser strategic aerosol monitor (SAM), and a weather station. Design and Methods: Two milking parlor sampling sites were established for the equipment, one site on each end (front and back) of the milking parlor center alley with cows on both sides facing the alley. Cascade impactors were loaded in duplicate with each of 10 different media. Vacuum pumps displaced 28.3 L of air/min, and media were exposed from 30 seconds to 15 minutes depending on the medium used. Statistically, the overall bioaerosol ANOVA model statement included the following parameters: one of 10 bioaerosol types; 2-stage or 6-stage impactors; winter and summer; parlor indoor aerosols compared to outdoor aerosol; AM and PM aerosols; and aerosols of 4 dairies. Conclusions: Milking parlor indoor aerosols colony forming unit(CFM)/m**3 for all bacterial types were significantly increased compared to outdoor aerosols. Mesophilic fungi were significantly increased in outdoor aerosols compared to indoor aerosols; however, thermophilic fungi were significantly increased in indoor aerosols compared to outdoor aerosols. Six-stage total mean microbial aerosols among dairy parlors ranged from 2,124 +/- 265 CFU/m**3 to 6,445 +/- 1,072 CFU/m**3, winter had 4,182 +/- 557 CFU/m**3 compared to summer's 3,519 +/- 438 CFM/m**3, and outdoor aerosols were 2.9 times lower than indoor aerosls. Six-stage total microbial mean respirable aerosols among dairies ranged from 693 +/- 104 CFU/m**3 to 1,995 +/- CFU/m**3.