1995 Volume 12 Issue 3 Pages 165-171
The effects of a portable air circulation system with installed ventilator and HEPA (high efficiency particulate air) filters on airborne microorganisms in the packaging area (packaging areas A and B) of two daily food plants were examined.
The bacterial counts at packaging areas A and B were 0.269-0.533 and 0.041-0.577 cfuper L of air, respectively, and after operation of the air circulation system, the counts were reduced to 0.056-0.132 and 0.026-0.028 cfu per L of air, respectively. The fungal counts at packaging areas A and B were 0.087-0.201 and 0.047-0.444 cfu per L of air, respectively, and after operation, the counts were reduced to 0.016-0.029 and 0.022-0.058 cfu per L of air, respectively. The microbial population at packaging area B tended to increase in the afternoon before operation of the air circulation system.
No significant differences were found among the effectiveness of the air circulation system for controlling airborne microorganisms pollution at each sampling point at packaging areas A and B.
The predominant constituents of airborne bacteria isolated from packaging area B consisted of 23.7% Staphylococcus sp., 20.1% Micrococcus sp. and 13.6% Bacillus sp., and after operation of the air circulation system, this composition was essentially unchanged. Throughout this research period, Listeria sp. was not detected.
