Share thisArchitects and engineers who design vivariums have a critical responsibility to provide specialty design and engineering that will facilitate cleaning procedures. Clean animal facilities are critical to the health and well-being of the animals, researchers, and animal care technicians who live and work in the facility. Clean facilities also help to ensure the accuracy of research by keeping potential contaminants at bay. In order to obtain AAALAC (Association for the Assessment and Accreditation of Laboratory Animal Care) accreditation, specific requirements and guidelines outlined in the National Research Council's “Guide for the Care and Use of Laboratory Animals” must be followed. When looking to obtain AAALAC accreditation, there are three important rules of thumb regarding clean facilities. First and foremost, the design and engineering of the vivarium must facilitate cleaning procedures; second, the leadership of the animal care program must actively promote cleanliness; and third, the animal care providers must be properly trained and motivated. The success of the latter two components is highly dependent on the first, and leadership of animal care programs will find that promoting cleanliness is much less of a challenge and the motivation and training of their staff much easier when a facility is “designed for clean.” Clean facilities are built around five key elements: well-designed planning concepts for corridors, circulation and holding rooms; a great HVAC system; the proper use of robotics; the application of correct finishes; and most important, detailing.
Programming - Where it all begins
Designing for clean all begins in the programming (or planning) phase. At this phase, corridor concepts will be determined, as will the plans for circulation patterns and animal holding rooms. (See Plans 1, 2, and 3).
Determining whether a single or double-corridor scheme will be used is fundamental. Both concepts are acceptable, but they each have their own benefits. On one hand, two-corridor schemes, with their designated clean and dirty sides, are inherently cleaner and thereby make a sterile environment easier to maintain. One-corridor schemes, on the other hand, are much less expensive and are just as sufficient at maintaining a clean facility.
It is important here to digress for a moment and make clear the difference between clean and sterile. When we talk of the term clean, we are referring to “kitchen clean.” Sterile, on the other hand, requires specific wipe-down procedures that are necessary when cross-contamination is an issue. This is especially true in barrier facilities. In such facilities, a double corridor system is needed to maintain a sterile environment. Non-barrier facilities, such as the University of North Carolina's Biomolecular Research Building, do not require a sterile environment and a one-corridor scheme functions perfectly well in maintaining an appropriately clean environment. It should be stated, however, that a two-corridor scheme alone does not prevent cross-contamination between the clean and dirty sides of a facility without the strictest of protocols. The benefit is derived from keeping the cage-processing movement to one corridor, thereby helping the other corridor maintain its cleanliness.
Circulation patterns should also be addressed at this point as they can have an important impact on the corridor scheme. Access to the many support areas found in a vivarium must be considered, especially the cage-washing areas. Many cage-washing facilities are separated into a dirty and clean side and others add an autoclave for decontamination, a critical component in bio-containment and barrier facilities. This dirty and clean side arrangement functions best when the access corridors also maintain this separation. The major obstacles to maintaining the clean-dirty concept are the additional square footage required and the associated costs of that square footage. Generally, the most effective net to gross ratio for a single corridor scheme is 60/65%, while double corridors function best at a 50/55% ratio.