Abstract
The aim of this study was to quantify microbiologically the operator protection factor (OPF) and measure the extent of cross-contamination provided by a new Advisory Committee on Dangerous Pathogens (ACDP) containment level 4 cabinet line system (glove box line). To accomplish this goal, the cabinet line was filled with microbial tracer aerosol, and microbial air samplers were used to detect any release of microbial tracer, both inside and outside the cabinet line when procedures were carried out. These procedures mimicked normal working conditions and realistic accident scenarios. The operator protection factors (OPFs) and internal cross-contamination ratios were calculated.
The cabinet line gave OPFs of between >106 and >107 in all tests. No cross-contamination was detected when internal doors remained closed between the individual cabinets and the spine. However, low levels of microbial tracer were detected moving from the contaminated cabinet to the spine but not to other individual cabinets when cabinet doors were opened.
These experiments demonstrated that the cabinet line provides a high level of protection for the operator and that multi-agents can be manipulated simultaneously within the cabinet line without cross-contamination. In addition, data have been produced, within a large primary containment system, from which informed risk assessments and procedures can be written. Such data provide a basis with which to compare primary containment with alternative ways of working with dangerous pathogens, such as positive pressure-suited systems.