Animal colonies used in research require abundant support materials such as feed, bedding, fresh cages, new animals, or other ancillary equipment. When any of these items need to be moved into the controlled environment of a vivarium, great care needs to be taken to prevent exposure of the colony to contamination. Many years of expensive research can be compromised as a result of contamination. The use of a Class II biological safety cabinet pass-through system substantially reduces the contamination risk associated with introduction of support materials.
Class II biosafety cabinets provide personnel protection by employing an inward velocity of air through the access openings. Product protection is accomplished by a downward unidirectional flow of HEPA filtered air that bathes the biosafety cabinet work area in clean air. Environmental protection is maintained by subjecting all exhausted air to HEPA filtration.
In a side-to-side pass-through configuration, two separate cabinets are connected by a buffer area that attaches the receiving side to the controlled side. This buffer area is engineered with unique air flows that prevent any migration of air (and any contaminants in it) from the receiving side to the controlled side. HEPA filtered supply air from both cabinets coupled with high velocity suction slots (along the walls and floor of the tunnel) insure product protection and cross-contamination control in both cabinets. Additionally, there are provisions to isolate each cabinet so that either can be decontaminated separately.
One side of the system is considered the “dirty” side (or receiving side) and the other is designated the “clean” side (or controlled side). A technician introduces an item into the clean side from the dirty side by placing the item in the receiving end of the biological safety cabinet system. The technician then performs a surface decontamination with an appropriate disinfectant and the item can be passed through to the controlled side of the system. Another technician receives the item in the controlled side and takes it into the facility.
A Class II vivarium pass-through biosafety cabinet system should connect to the facility’s HVAC system to allow a differential pressure between the receiving side and clean side to ensure protection for the vivarium. Alarms systems are programmed to alert when either of the cabinets’ flow rates are not within pre-set parameters or if the room intake and exhaust systems are out of ranges. Additionally the cabinets are canopy connected to the exhaust for a more robust operation with few nuisance alarms.
Programmable logic controller (PLC) based monitors on each cabinet are interconnected and equipped with alarms for low exhaust flow, inadequate room air supply volume (causing unacceptable variances in room differential pressure), and sash position. These PLC controllers can be connected to building monitoring systems for remote monitoring. Other important features that are useful in a pass-through system include an intercom system to allow technicians on each side to communicate effectively.
Routine cleaning and maintenance is quick and easy. All work surfaces, including the integrated tunnel connection, are easily removed. Each cabinet is equipped with a drain valve to drain any disinfecting liquids or spills. Coved and radiused corners facilitate cleaning.
Preserving the integrity of controlled environments is critical in a vivarium. Implementation of a Class II biological safety cabinet pass-through system is an effective solution for safeguarding research and the sizeable investment made in animal colonies.
For 60 years, Baker has responded to our customers’ changing needs with creative solutions to the most sensitive and complex containment challenges. We are always glad to recommend a solution to fit your needs and budget. In fact, some of our most innovative and successful products were originally developed in response to a customer’s unique situation.
See how our dual-sided biosafety cabinet helped Jackson Labs, one of the world’s leading distributors of human disease mouse models, increase the efficiency of the cage-changing process and improve the overall work environment for its technicians in our SterilGARD Duo Case Study.