Nevertheless, the demand for biocontainment labs is surging on campuses across the country, and successful retrofits happen, as exemplified by two projects recently completed by the FWA Group, Charlotte, N.C. At the Medical University of South Carolina (MUSC), an 1,800-sf BSL-3 lab on the top floor of the basic sciences building came on line in January 2007. A similar retrofit to Virginia Tech University’s Fralin Biotechnology Center, also completed in January of this year, resulted in a total of 1,350 sf of BSL-3 and BSL-2 space. Construction costs were $1,850,000 and $835,000, respectively.

The obstacles presented by these projects ranged from less-than-optimum location choices to minimal overhead and rooftop space, topped by funding delays. In both cases, the project experience highlights just how important it is to get those critical first steps right in order to deliver a successful BSL-3 retrofit.

Planning Considerations

The predominant mission of BSL-3 space is to establish failsafe containment, and to maintain it indefinitely.

“Safety—the protection of people both inside and outside the facility—is the ultimate priority,” says Bill Foust, principal and partner at the FWA Group. “Everything else takes a back seat,” adds his colleague Randy Larsen, also an FWA principal and partner with considerable expertise in containment requirements.

While there are a myriad of elements—many related to mechanical systems—that have to work together to accomplish that mission, it all starts with the right planning. The architects’ first credo is that a successful small BSL-3 retrofit requires a reliable estimate of space. It is essential to understand the workflow to provide adequate entry, circulation, and exiting for both people and material. Typically, the most difficult requirements to determine at the outset are the ancillary needs driven by the SOPs (standard operating procedures). For example, some protocols mandate that personnel shower both on the way in and out of the containment area. In other situations, donning protective clothing in the locker room is sufficient. Eliminating the shower saves on real estate, but it also imposes limits on which agents can be studied in the future.

Finding the space for mechanical systems is a big challenge. Of the three typical options—below, overhead, or on the roof—in a retrofit the first is usually ruled out because it’s already occupied. Equipment generally winds up shoehorned into the five feet or less above the ceiling or on the roof. This last alternative is not only visually undesirable but also exposes maintenance staff to the elements. It can also spur concerns about re-entrainment, making it essential to resolve these issues in the planning stage.

Designers don’t always have the luxury of choosing which building will house the BSL-3 space. While it’s debatable whether a remote or close-in site is preferable, provisions have to be made to isolate the physical facility from its surroundings while maintaining its security. For example, as a protective measure at MUSC exterior windows retain their original appearance on the outside while filled in from the interior.

Once the building has been identified, the capabilities of the existing structure must be analyzed to understand what needs to be done to accomplish both the science and containment. Considerations include floor-to-floor heights; existing system capacity; exhaust control; ductwork sizing and routing, whether going up or down; the existing utility infrastructure; and the potential need for supplemental utilities in the designated area.

Often, the proposed site has less to do with suitability than with what is or could be made available. Ground floor locations simplify delivery and disposal, but they also require longer exhaust ductwork runs and afford less protection from attack. Going up a few floors to an intermediate level offers “the best or worst of all worlds”—some distance from the ground floor but still with vertical transportation needs. The top floor, as isolated as possible within the building, often winds up as the retrofit site. If that is the choice, special care must be taken to manage material movement, especially hazardous waste disposal, through effective controls. Putting the containment facility on the interior, away from outside walls, appears to be preferable, but again space availability usually dictates that choice.

“A particularly difficult issue is finding the right funding for the construction and the rest of the project,” Foust comments. Administrators are not accustomed to the cost-per-sf numbers this type of construction generates. The MUSC BSL-3 renovation hit $1,100 per-sf in 2006 dollars. In contrast to a typical biochemistry laboratory, where engineering systems, HVAC controls, plumbing, fire protection, electrical, and security account for approximately one-third of the typical building cost, the engineering systems for a BSL-3 retrofit now consume almost three-quarters of the budget.

Larsen relates that the MUSC renovation experienced a five-month delay as the administration searched for extra money to provide the desired level of biocontainment. The Virginia Tech retrofit was constrained by the University’s $1 million small-project cost ceiling. Negotiating reductions and using the University construction crew got the budget down to $853,000, but it also incurred a four-month delay.

“All parties have to realize that BSL-3 design is expensive to begin with, and you can’t rely on rule-of-thumb pricing from other science facilities, especially if they are new construction,” Larsen observes. “In small renovations, there are no economies of scale.”

He and Foust also recommend early involvement among the key professionals involved in design and construction of the facility, bringing in not only experienced architects and contractors whose qualifications have been verified, but also a commissioning agent.

“The goal is to provide yourself with a complete, well-qualified team to initiate this project,” says Foust. “It is critically important to success to make sure that all planning items are followed.”

SOPs Rule Design

In the design phase, the facility’s SOPs are critical to achieve containment.

“Everything that goes on in a biocontainment lab follows an SOP,” Larsen remarks, noting that there are often different ways to produce the same result. For example, isolation when entering the biocontainment suite can be accomplished either through a door interlock or with a protocol mandating a visual check of open doors.

“Designers don’t need fully detailed SOPs,” he continues, “but the SOP concepts have to be in place or the resulting facility will be very difficult to work in.”

Foust advocates inviting the institution’s biosafety officer to review SOP development
“to make sure that the protocols being established can maintain containment and biosafety. The key here is that the design complies with all the SOPs and the BMBL [Biosafety in Microbiological and Biomedical Laboratories] guidelines.”

On the mechanical side, especially in older facilities, a new, stand-alone air-handling system will probably be required to deliver the pressure relationships essential for containment. Beyond carving out the space, the designers need to consider a dedicated exhaust path and the ductwork to discharge it high enough above the building. HEPA filtering might also be necessary.

The step of adding new equipment, even for the small BSL-3 footprint, will probably affect air distribution on the remainder of the floor, calling for an upgrade to the building management system (BMS) and the installation of new controls. This work has to be budgeted in initial planning, Larsen advises.

Redundancy provisions are another key piece of the design. The architects have a long list of critical equipment that should have back-up power: air handling units and exhaust fans, chillers, towers, water pumps, air compressors, BMS, security system, biosafety cabinets, autoclaves, and sometimes fume hoods, incubators, freezers, and cage racks. Lights should be outfitted with back-up batteries as any potential interruption to vision could have serious consequences.

“In BSL-3 spaces we frequently find that the correctly sized generator is big enough to run the entire facility, but that’s part of what it takes to get failsafe containment,” Foust notes.

When it comes to maintenance access, allowances are usually made for larger items like fan motors, pumps, disconnects, and filters,  but sometimes the smaller things like balancing dampers and VAV boxes are overlooked.

“You have to locate them in an area where a mechanic has access to perform repairs. There is no question of ‘if’ it is going to break; it will break,” Larsen emphasizes. He also mentions the reluctance of maintenance staff to enter the containment area itself, especially if showering is involved.

“Water faucets, water polishers, clean-outs, lights, and ballasts--all these kinds of things have to be inside the facility. Either the normal maintenance personnel are going to have to take care of them, or the people working inside have to learn how to do those jobs.”

Finally, penetrations in the secondary barrier—the kind made for piping and ductwork—need special attention. Foust points out that the transitions between floors, walls, and ceilings are all an integral part of the secondary barrier, and contractors need to maintain their integrity, especially in areas where the openings occur out of sight.

Construction Issues

Critical factors in construction include contractor selection and education, coordination of trades, and final building commissioning.

The relatively low dollar value of such projects tends to attract smaller contractors who may not understand biocontainment and biosafety. Pre-qualifying contractors, especially those doing the mechanical work, “to the best extent possible allowed by state law” is one way to weed out those who don’t have the requisite skills and at least comparable experience.

Contractors that don’t have a BSL-3 history should be educated about the rules and procedures in pre-bid meetings with the biosafety officer before the project, and special scoping meetings should be held with the critical trades, with weekly reiteration once the job starts. Any contractor objections or disagreements about unfamiliar practices should be countered with a reminder about the unique requirements of the facility.

“We are aiming to spread biocontainment and biosafety knowledge throughout the entire construction team so that everybody knows how important things are,” Foust remarks.

The three-dimensional images generated during the design phases have proven to be a very useful tool to coordinate the trades and minimize the impact of construction on other building occupants.

“Retrofits take an area of the building out of operation, creating hardships to the other users on the floor. Any kind of a delay in moving forward just makes things all the more difficult, so that coordination is key,” says Larsen.

Finally, commissioning the facility is crucial to BSL-3 work. Despite all the professional input, the sheer complexity of such projects demands that commissioning agents get involved early and coordinate their activities with the construction schedule.

“That’s the only way to confirm the construction success you are expecting,” Foust concludes.

By Nicole Zaro Stahl

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