“The first thing that always strikes me about animal barrier facilities is the amplification of all of the issues,” says Tim Reynolds, senior principal and lead electrical engineer for The Clark Enersen Partners, the architectural and engineering design firm for the NSRRC. “Everything is more critical in the planning and design process because you have to address issues that are not typically encountered in research facilities or other types of facilities.”

A key component of the NSRRC is its barrier facility, which is a pathogen-free environment. The Center contains animal holding areas, treatment and procedure rooms, research space, cryogenic freezing, and storage facilities within the barrier. Many design and construction issues for barrier facilities are similar to those for biocontainment environments. The major difference is that the goal in a biocontainment environment is to keep pathogens inside the designated space, while the objective in a barrier facility is to keep pathogens outside the area. Regardless of the type of facility, the planning process must be comprehensive enough to build a solid foundation for the project’s future success.

Planning Process

Planning for a barrier facility such as the NSRRC begins with the owner initiating and defining the project and its goals. The owner must develop the program, establish the size of the project, create a budget, identify funding, determine the location and site for the facility, set the schedule, and acknowledge any opportunities or issues related to the project.

“Defining and balancing the program at a public institution like the University of Missouri-Columbia is sort of a three-legged stool,” says Jude Wawrzyniak, facilities project manager for the University. “We have to balance the input between three entities, including the user groups, the institution, and the stakeholders.”

Gathering input from all of the involved entities is best achieved by conducting charrette sessions, or workshops, which can range from a one-day intensive meeting to a week-long session. The design team is able to weigh and balance input from all perspectives and build a consensus project solution.

The user groups consist of the principal investigators, the research assistants, the animal care group, and the barrier facility manager or operations manager. Grant requirements are brought to the table as part of the discussion among the user groups.

Institutional goals are primarily centered around the site, which should include discussion about the context of the site to the campus master plan and the profile or image of the project on campus. It is also important to determine whether the site can offer non-detectable operations, meaning a place where research can occur but not be seen by the public when it comes to animal research facilities.

Proximity to the individuals who will use the lab must be considered because researchers want the animal facility as close to their labs as possible. However, labs are often located in high-profile areas of the campus where animal barrier facilities may not be appropriate. Therefore, these facilities often get relegated to more remote areas of campus where the roads and infrastructure may not be sufficient. The cost of providing this infrastructure can become a significant portion of the project costs. It is important to note that barrier facilities require a tremendous amount of utilities.

Other institutional goals focus on grant obligations associated with the project, time commitments, how long the facility must be in operation to support the research, and recruiting efforts to attract top researchers.

The stakeholders are defined as individuals associated with the University, as well as those from external entities, who participate in the planning process but do not contribute any capital money to the project. They take part in the planning because they are instrumental to the successful operation of the facility once it is completed. The stakeholders include individuals who work in maintenance, energy management, environmental health and safety, grounds, fire department, and utility companies. Neighbors on the campus and in the local community also are included in this group.

Project Costs and Budget Distribution

Another major aspect of the planning process is establishing project costs and making sure all of the involved groups understand how the costs are distributed.

“One of the toughest things we deal with on every project is when users believe they should have $10 million to spend on a building if they have a $10-million budget,” says Greg Lattig, senior partner, architect, and lab planner with The Clark Enersen Partners. “They do not realize there are soft costs and other costs associated with it.”

A general guideline, established and utilized by The Clark Enersen Partners and the University of Missouri, indicates that hard construction costs can account for between 50 and 75 percent of the project dollars, while other construction costs can range between zero and five percent. Design and bidding costs may be between eight and 15 percent; project and construction management, two to 15 percent; site development, five to 20 percent; chiller plant costs, zero to eight percent; and project contingency, two to eight percent.

After all of the costs are outlined, it is essential to discuss the preliminary size of the facility by determining the expected net-to-gross ratio. The facility size is driven by the program, the budget, and the particular site. The net square footage (NSF) is the usable area in a facility and the gross square footage (GSF) is the overall building area. The number, size, and type of animals to be housed in the facility must be considered, as well as the associated support spaces that will be required.

The basic discussion of NSF versus GSF is often misunderstood as the academic world tends to speak in terms of NSF while the design and construction community relates all discussions to GSF. Early in the design process the confusion related to these terms can often lead to diverse expectations of project costs.

“We generally like to start out with an expected net-to-gross ratio in an animal facility of between 30 and 50 percent, preferably 40 percent,” says Lattig. “The expected cost per square foot for a vivarium is between $400 and $500, and some of the larger animal facilities are between $250 and $300.”

The NSF is determined by multiplying the construction budget by the net-to-gross ratio and then dividing by the construction cost per GSF. The construction budget is equal to the construction cost per GSF multiplied by the NSF and divided by the net-to-gross ratio.

Design and Construction Issues

Animal Welfare

The welfare of the animals is a paramount concern when designing and constructing any animal housing whether it is a barrier facility or a biocontainment facility. The NSRRC includes nooks covered with canvas where the swine can nest because they like to go into places where they can trap their body heat. Paying attention to animal welfare in a rodent facility could be as simple as providing properly ventilated rack systems.

Process Flow

Process flow must be figured into the design of a barrier facility. Entrances and exits, for example, must be carefully located to facilitate the convenient flow of people coming into the building, animals being brought in and taken out, and the supplies that must be delivered.

The NSRRC produces new swine models for research and some of the animals are shipped to other institutions. The genetically modified animals are so valuable that they do not give live birth. Instead, they undergo cesarean sections. The Center accommodates this type of veterinary work within a surgery suite, which includes an adjacent nursery and farrowing area.

The micromanipulation of all genetic material is done on site inside the barrier environment. Six to eight people work in the barrier environment on a daily basis to do the lab work and to care for the animals, which will number about 250 at full operation. A shower-in area must be used by everyone who works in the lab to ensure they are free of contaminants. A break room and office areas are provided for people who spend a lot of time working at the Center.

A loading dock has an entrance through an interlocked fumigation chamber, where vaporized hydrogen peroxide is used to disinfect bagged feed and bagged bedding. A wipe-down airlock is available for the delivery of products, such as pharmaceuticals, that cannot be fumigated and must be disinfected by hand.

Another example of process flow involves a renovated barrier facility for rodents on the University campus. The facility was enlarged to include a pass-through autoclave, a pit-mounted autoclave where racks could be sterilized before going back into the barrier. The renovation was difficult due to budget constraints and the location of the mechanical support systems, so the sterilizer was made smaller than originally designed and it is not pit-mounted.

“It is actually used with presentation racks or loading carts; the only thing that is sterilized going back in are the cages,” says Andrew Stepp, associate principal, architect, and laboratory planner for The Clark Enersen Partners. “There is a gowning area for people who work in that space, there are interlock doors, and there is an inner locked airlock for the exit of dirty cages. The cages go into the existing soiled cagewash area through a tunnel washer and are sent back in through the sterilizer. This is just one example of a detail that we use for barrier penetrations.”

Barrier Integrity

One of the most important aspects from an architect’s standpoint for a barrier facility is defining where the barrier is to ensure its integrity. It has to be defined in the horizontal and vertical plane regarding the ceilings, walls, and floors. If the barrier is penetrated, great care must be taken to put an airtight seal on the penetration to prevent pathogens from entering the facility.

Penetrating the floor at the NSRRC to install an electrical conduit involved a steel sleeve with a welded water stop that is actually set in the floor before the concrete is poured. After the concrete is poured, the conduit is fitted into the sleeve and a compressible filler is put in. It is known as a link seal where the compressible neoprene material has bolts and nuts on it that are tightened down. As the material compresses, it fills and seals the space. Seal-off fittings are used to fill conduits with sealants so pathogens cannot enter the open conduit.

“We spent a lot of time coordinating as a team between the architects, MEP engineers, and our structural engineers to create a sleeve package so that every penetration through the penthouse floor, for example, was accounted for and the sleeves were shown in the structural plans to make sure they were installed correctly,” says Shawn Diederich, principal and lead mechanical engineer for The Clark Enersen Partners. “We also recommend doing mock-ups for any barrier facility, and you have to assume that the contractor has never built a facility like this before.”

Pressurization

Pressurization is important for barrier facilities and is often considered the safety net for defects in construction, cracks around doors, and any other problems that might cause a physical breech of the barrier. The surgery suite at the NSRRC has the most positive pressurization in order to avoid contamination from pathogens.

Engineers must consider how changing the pressurization in one area may impact adjacent spaces. A negatively pressurized airlock is used at the NSRRC to keep the odors from the animal areas out of the laboratories.

Redundancy

“The way we maintain that pressurization is through the use of redundancy,” says Diederich. “You want to use redundancy as often as you can, but there are cost implications.”

The swine facility has two air handlers, each capable of handling 75 percent of the peak load. They normally run together, each at a reduced speed, to handle the full building load. If one air handler fails, the other can ramp up and still maintain the barrier with the right pressurization. This is achieved by using a series of controls and making sure the animal spaces are always ventilated at the same rate. Other areas have a reduced rate during a power loss or equipment failure.

Temperature and Humidity Control

It is critical to control the temperature and humidity in any animal facility, especially in a barrier environment. If the humidity outside the barrier space is higher than the level inside the barrier, the tendency is for the humidity to migrate into the barrier space no matter how well the wall is sealed. In order to avoid this problem, efforts should be made to keep the temperature and humidity outside the barrier space as even as possible with the conditions inside.

Energy Efficiency

Since barrier facilities require a lot of energy, it is imperative to find an appropriate energy-recovery system. The least efficient energy recovery system is used at the NSRRC because it offers maximum protection against cross contamination. Many systems were considered, but the final decision was made to use a basic run-around loop system in order to eliminate the potential of cross contaminations. This particular system also helps keep odors out of the labs. The benefits of the system made it a cost-effective solution.

Maintainability

Keeping as much equipment as possible outside the barrier in the swine facility has a positive impact on operations. It eliminates the need to have maintenance people shower before going into the barrier facility to repair and maintain equipment.

“We located as much equipment as possible that was maintainable outside the barrier,” says Lattig. “There are certain things in the barrier that have to be maintained, so at some point maintenance people will have to be in the barrier. They are going to be familiar with the procedures and the protocols for going into the barrier, or the animal care staff will have to know some of the maintenance functions.”

Security and Safety

Sometimes, security and safety are mutually conflicting ideas. Airlocks in certain barrier facilities are interlocked with standard double doors. If one door opens, there is usually a lock on the other door that prevents it from being open at the same time. Code authorities must be consulted to determine parameters for exiting the facility. The NSRRC is considered a fail-safe environment, designed to facilitate the safe exit of people and animals in the case of an emergency. Many biocontainment facilities are fail-secure, meaning that first responders in an emergency cannot get into the building unless they are escorted by someone from within the facility.

It is also critical to consider shutting down exhaust fans in an emergency if the air handlers fail in a barrier facility. This will keep the facility at neutral pressurization and prevent pathogens from entering the building.

Waste Management

A “pull-the-plug” method of waste management is used at the swine center. Pits are located under all of the animal pens and an eight-inch drain pipe with a plug is located at the end of each pit. The pits are charged with six to 12 inches of water and remain that way for a week, and the cages are washed down every day. All of the waste runs through the grating and slowly rises during the course of the week. When the plug is pulled out, all of the waste runs down into the pit and then into a waste treatment plant located 100 yards away.

A solids separator unit housed in the waste treatment plant separates the liquid wastes from the solids. The solids are collected in a bin and can be used for composting or disposed of in another manner. The liquid waste is discharged into the city sewer system.

Odor is controlled with exhaust ducts that extend down to the top of the pits and exhaust air through the pit grating.

Phasing

Periphery costs must be considered when phasing a project or completing a renovation.

“Sometimes it is more expensive to renovate than to construct a new building, but there are reasons to do renovations,” notes Lattig. “In the case of renovations, the animal population must be vacated from the building so there are temporary costs associated with phasing. Be cautious and understand the implications of renovations.”

By Tracy Carbasho

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