Ziemann B, Corn M, Ansari A A, Eggleston P
Bristol Myers Squibb, Industrial Hygiene Department, Syracuse, NY.
Am Ind Hyg Assoc J. 1992 Feb;53(2):138-45. doi: 10.1080/15298669291359401.
The Duo-Flo BioClean unit, consisting of a chamber unit with an animal rack, a HEPA filtration system, an air plenum, and a blower, was evaluated as a control unit for airborne rat antigen levels in the room housing the unit. The unit was evaluated in negative and positive pressure operating modes. In the negative mode, room air is drawn into the unit, passes over the animal cages, and is then exhausted into the room through the filters. In the positive mode, air passes through the filters, traverses the animals, and then is discharged into the room. Airborne antigen concentrations (ng/m3) and particle size distributions associated with antigen were measured during the two operating modes and prior to operation (background mode). Airborne antigen concentrations during the positive pressure operating mode were higher than during the negative pressure mode or background. Approximately 70% of airborne antigen was associated with respirable particles during background and positive pressure operating modes. A total of 36% of airborne antigen mass was associated with respirable particles during negative pressure operation. The unit is usually operated in the positive mode to protect experimental animals. This study clearly indicates that negative pressure operation would reduce the dispersion of dust-containing antigen, the exposure of room occupants to airborne antigen, and the risk to many workers of contracting animal allergy.
双流式生物清洁装置由一个带有动物饲养架的腔室单元、一个高效空气过滤器（HEPA）过滤系统、一个空气静压箱和一个鼓风机组成，被评估为该装置所在房间内空气传播大鼠抗原水平的控制单元。该装置在负压和正压运行模式下进行了评估。在负压模式下，室内空气被吸入装置，经过动物笼，然后通过过滤器排放回室内。在正压模式下，空气通过过滤器，穿过动物，然后排放到室内。在两种运行模式期间以及运行前（背景模式）测量了空气传播抗原浓度（ng/m³）和与抗原相关的粒径分布。正压运行模式下的空气传播抗原浓度高于负压模式或背景浓度。在背景和正压运行模式下，约70%的空气传播抗原与可吸入颗粒相关。在负压运行期间，共有36%的空气传播抗原质量与可吸入颗粒相关。该装置通常以正压模式运行以保护实验动物。这项研究清楚地表明，负压运行将减少含尘抗原的扩散、室内人员接触空气传播抗原的机会以及许多工作人员感染动物过敏的风险。
