Kang Y J, Frank J F
Animal and Dairy Science Department, University of Georgia, Athens 30602.
J Dairy Sci. 1990 Mar;73(3):621-6. doi: 10.3168/jds.S0022-0302(90)78712-7.
The viable aerosol in dairy processing plant environments was characterized by using an Andersen six-stage sieve sampler and a Reuter centrifugal sampler. Artificially introduced Serratia marcescens were detected in the air during drain flooding and after rinsing the floor with a pressured water hose, thus illustrating the ability of a specific microorganism to be disseminated from drains and wet surfaces via physical disruption activities often observed in food plants. Once a high concentration of wet viable aerosol was generated, it took 40 or more min to return to the background level in the absence of forced ventilation or other activity. The greatest reduction in viable particles occurred during the first 10 min. Estimated mean aerosol particle sizes were decreased from approximately 4.6 to 3.2 mu with time lapse. The estimated mean aerosol particle sizes from actual dairy processing plant environments ranged from approximately 4.3 to 5.3 mu. In addition, a more heavily contaminated dairy processing environment contained larger aerosol particles. These results indicate that the RCS sampler will often overestimate the true aerosol concentration in highly contaminated air, because mean particle sizes are over 4 mu in diameter.
通过使用安德森六级筛孔采样器和路透社离心采样器，对乳制品加工厂环境中的可存活气溶胶进行了表征。在排水口溢流期间以及用高压水软管冲洗地面后，在空气中检测到人工引入的粘质沙雷氏菌，这表明特定微生物能够通过食品工厂中经常观察到的物理破坏活动从排水口和潮湿表面传播开来。一旦产生高浓度的潮湿可存活气溶胶，在没有强制通风或其他活动的情况下，需要40分钟或更长时间才能恢复到背景水平。在最初的10分钟内，可存活颗粒的减少最为显著。随着时间的推移，估计的平均气溶胶粒径从约4.6微米降至3.2微米。实际乳制品加工厂环境中估计的平均气溶胶粒径范围约为4.3至5.3微米。此外，污染更严重的乳制品加工环境含有更大的气溶胶颗粒。这些结果表明，RCS采样器通常会高估高污染空气中的真空气溶胶浓度，因为平均粒径超过4微米。
