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4 Evaluation of Design Plans and Personnel Preparedness FACILITY DESIGN FOR BIOSAFETY AND BIOSECURITY Facility-related design guidelines for high-containment laboratories have been developed to reduce the potential for escape of human and animal pathogens due to mechanical failure, to ensure that rooms that house animals maintain environmental parameters, and to enable continuity of operations (AS/NZS, 2002; USDA-ARS, 2002; Public Health Agency of Canada, 2004; Mani and Langevin, 2006; UK-HSE, 2006; CDC, 2009). These design guidelines collectively and in most cases independently identify the requirement for reliable systems that have been demonstrated to be capable of maintaining containment, and they identify the need for monitoring by the engineering staff and users to ensure that systems function in accordance with their design and intended functions. These guidelines also identify inherent challenges associated with engineering components, including the need for maintenance (which requires shutdown of systems), instances of malfunction and repair, and the physical limitations of systems. To reduce risks of biocontainment failure associated with failure of engineering components—such as high- efficiency particulate air (HEPA) filters; waste-effluent treatment systems; autoclaves; heating, ventilation, and air-conditioning (HVAC) exhaust fans; and backflow preventers—design guidelines advocate or require the use of redundant components. For example, the use of parallel filter banks would allow cleaning and decontamination of filters without the need to shut down operations. Management of Solid and Liquid Waste Residuals management is a paramount containment issue for the National Bio- and Agro- Defense Facility (NBAF). Residuals are defined here as bioaerosols, solid waste, liquid waste, and sanitary flows (sewage and associated wastewater) generated by NBAF operations. With respect to the immediate infrastructure for the containment, collection, and treatment of residuals generated by the NBAF’s proposed laboratory and suite of operations, the committee has confidence in the experience and the ability of the civil, environmental, and architectural engineering teams to design systems that meet or exceed the specialty residual decontamination challenges for this unique facility. Such experience would include, but not be limited to, parallel design and operational practices of experimental animal facilities that have similar charters and 51

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EVALUATION OF THE NBAF SITE-SPECIFIC RISK ASSESSMENT 52 occupational and environmental standards for containing human infectious diseases specified in the fifth edition of Biosafety in Microbiological and Biomedical Laboratories (BMBL) (CDC, 2009). Given the stage of the infrastructure pre-design presented in the site-specific risk assessment (SSRA) and U.S. Department of Homeland Security (DHS) responses to technical questions about the design and projected effectiveness of the different residuals management systems, the committee has a reasonable degree of confidence in the design and operations of the sanitary and solids handling systems. However, the committee remains unsure about the following sanitation-driven air-quality engineering issues: o How relatively large indoor bioaerosol loads—in terms of mass, particle size distribution, and agent longevity—would differ markedly from those in biosafety level 3-4 (BSL-3/BSL-4) facilities that do not house cohorts of large animals. o How such bioaerosol loads are likely to affect the design and operations of the associated indoor air quality systems. DHS responded to direct technical questions 35-41 in their follow-up letter (pages 27-31, July 28, 2010). By reasonable and customary practical engineering standards, the committee agreed that the design, operation, and maintenance information provided was sufficient to judge how the sanitary infrastructure will likely perform as individual treatment processes. The projected sanitary performance has a sound basis as judged by the loads and designs of facilities that have similar charters. Also, the projected redundancies are in accordance with those of facilities that have similar charters, but need to be appropriately scaled for the projected NBAF loadings. The recent announcement of a wastewater treatment plant on the NBAF campus will need to be clearly justified and explained with respect to its service intents and mission over the design life of the NBAF. Air Handling and Air Filtration Systems As the NBAF progresses through the design phase, it is important that a commitment be made to not “value engineer”1 out critical secondary containment systems in BSL-3Ag and BSL- 4 spaces that will house large animals. Certain features of the large animal rooms will act as primary barriers for containment, such as HEPA exhaust filters and the sealed and pressure- tested room surfaces (USDA-ARS, 2002). At a minimum, NBAF should comply with national guidelines2 that were developed to reduce the risk of escape of severe foreign animal pathogens, 1 Value engineering refers to a practice where the architect and engineering firm is asked by the owner or building proponent to find elements that can be removed from designs to reduce costs. The owner weighs the risk and impact of the proposed changes against the benefit of the cost reduction to determine which elements are safe to remove so they are no longer part of the facility construction. 2 In designing and operating modern, high-level biocontainment facilities, both the BMBL and the U.S. Department of Agriculture’s Agricultural Research Service facility design standards strongly recommend backup HEPA filter units to allow filter changes without disrupting research (USDA-ARS, 2002; CDC, 2009). The guidelines state that “the most severe requirements for these modern, high level biocontainment facilities include HEPA filters arranged both in series and in parallel on the exhaust side, and parallel HEPA filters on the supply side of the HVAC systems serving ‘high risk’ areas where large amounts of aerosols containing BSL-3-Ag agents could be expected (e.g., large animal rooms, contaminated corridors, necropsy areas, carcass disposal facilities, etc.)” (USDA-ARS, 2002; CDC, 2009). For these high-risk BSL-3Ag and BSL-4 areas, redundant supply and exhaust fans are recommended (ref Appendix D point 6, CDC/NIH BMBL, 2007).

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EVALUATION OF DESIGN PLANS AND PERSONNEL PREPAREDNESS 53 such as foot-and-mouth disease virus (FMDv), that can result in catastrophic economic loss, and of potentially lethal zoonotic pathogens, such as Nipah and Hendra viruses, that have medium to high lethality and for which no vaccines or treatments are available. For BSL-3Ag spaces, the guidelines strongly recommend two HEPA filters installed in series and a parallel redundant bank of HEPA filters so that one or both of the HEPA filters in the primary bank can be replaced while the room is still operational (“hot”) (CDC, 2009). Replacement may be needed because of filter loading, damage that results in leakage, or other factors that may compromise filter performance. The SSRA falls short of recognizing that BSL-3Ag areas will generate much greater concentrations of pathogens than typical laboratory-scale work because of the large animal component in BSL-3Ag areas: infected animals shed significant amounts of pathogens. Secretion and excretion from infected animals, combined with routine maintenance and cleaning of animal areas, will most likely result in a much higher potential for pathogens to aerosolize. The secreted and excreted materials will be contained in nasal, oral, fecal, and other exudates that provide a protective bioburden matrix. Upon aerosolization, the matrix droplets will likely contain higher concentrations of virus than will be seen in the research laboratory setting. Furthermore, the SSRA does not discuss or describe the effects of additional residues—such as animal hair and food residues—that may also become aerosolized by the animals themselves or by cleaning processes, each of which may shorten the life span of the HEPA filters because of loading beyond normal operational limits. The committee concludes that because of the high rate of viral shedding, high concentrations of aerosolized virus due to animal and caretaking activities, and the increased probability of filter loading, the NBAF will need to use both HEPA filters in series and redundant (i.e., parallel) systems for BSL-3E special procedure rooms and BSL-3Ag and BSL-4 spaces. The committee is seriously concerned that the current NBAF design strategy omits a parallel redundant bank of HEPA filters for BSL-3Ag and BSL-4 animal rooms (see Figures 3- 21 through 3-28 of the SSRA). The SSRA depicts the use of two HEPA filters in series for BSL- 3 special procedure rooms, BSL-3Ag, and BSL-4, but it does not address the need for a redundant series of HEPA filters in case the primary bank of filters requires replacement. Something as simple as blockage of a coarse exhaust filter becomes a major issue if the room is filled with animals infected with a dangerous pathogen. Parallel systems help alleviate such problems and allow more continuous use of expensive laboratory and animal space with minimal downtime for maintenance. The decision to omit parallel redundant series of HEPA filters was made in contravention of both the BMBL and USDA ARS Facility Design Standards strongly recommending both HEPA filters in series and parallel redundant systems for BSL-3Ag and BLS-4 spaces. Appendix C of the SSRA states that “the [DHS-convened qualitative risk assessment subject matter expert] panel expressed concerns regarding the practicality (size, space, configuration, maintenance, costs, etc) of parallel (fully redundant) series HEPA exhaust pathway.” The committee is troubled that reasons of practicality and cost-saving measures would possibly trump and compromise critical design safety measures. The SSRA’s plan to omit redundant filters is not in accordance with best practices and guidelines and is an example of the type of value engineering that should not occur. The use of select agents, including the 8 pathogens that the NBAF will study, requires registration with the CDC or USDA and compliance with the most recent BMBL guidelines. Furthermore, if the NBAF is intended to be a state-of-the-art high-biocontainment facility, it will need to employ state-of-the-art biocontainment designs, operations, and practices, such as the use

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EVALUATION OF THE NBAF SITE-SPECIFIC RISK ASSESSMENT 54 of HEPA filters both in series and redundant filter banks. Removing redundant HEPA filters will result in a facility whose safety engineering is not equivalent to the safety engineering found in existing biocontainment facilities, and the NBAF will fail to be considered state-of-the-art. The committee is aware that the budget for the NBAF is congressionally approved and has been programmed years in advance of construction, and that costs of building complex biocontainment facilities tend to increase during the time required to complete construction. Point 44 of DHS’s July 28, 2010 follow-up letter states that “the BMBL description of HEPA series and parallel requirements is indeed very severe” (page 32). The committee cannot think of many things more severe that are related to this project than the escape of foreign animal diseases in an agricultural environment such as that of Manhattan, Kansas. The redundant HEPA filters in the BSL-3E special procedure rooms and BSL-3Ag and BSL-4 areas present a necessary expense in weighing the consequence of pathogen escape from these high- biocontainment areas. In the event that Congress does not approve supplemental funding, a rational and responsible alternative to engineering out the needed safety systems, such as redundant HEPA filters, is to reduce the operational square footage of high-cost areas. An example would be to reduce the square footage of completed BSL-3Ag holding rooms by abbreviating the length of stainless steel ductwork initially installed for the HVAC and stubbing the plumbing and electrical installations that lead to the containment rooms until funding is available for completing the project. That solution has been applied to comparable containment facilities, does not compromise safety, and ensures that the facility can accommodate future increased capacity to fulfill the NBAF mission. With respect to sanitary and air-quality infrastructure, the committee finds that the methods used to assess and predict the sanitary, solids, and bioaerosol loads are adequately presented. Given the scale and challenges associated with biocontainment in this facility and the engineering design and maintenance information presented, the committee has confidence in the projected performance and reliability of the sanitary systems and solids management systems, but does not have confidence in the projected performance of the associated air quality systems as currently designed. The design plans are still in a nascent stage, therefore committee could not assess how the individual containment and treatment systems might perform when integrated into the synchronized network, which is to maintain this facility as an immune building under its full operational load. PERSONNEL TRAINING AND PREPAREDNESS The SSRA indicates that the most probable cause of accidental release will be human error. Human error can be reduced by rigorous hands-on training in laboratories that will have comparable biocontainment and biosecurity practices. However, SSRA timelines do not provide for that level and extent of training and could increase the probability of an inadvertent release or human exposure. Personnel Practices As noted in the committee’s preliminary letter report: “it would be useful to consider the risks associated with the lack of respiratory protection for workers that come into contact with FMDv. It is a common recommendation that workers exposed to FMDv-infected animals not

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EVALUATION OF DESIGN PLANS AND PERSONNEL PREPAREDNESS 55 contact other susceptible animals for 5 days—as a result of studies demonstrating recovery of virus from nasal passages (Sellers et al., 1970, 1971)—to reduce the risk of respiratory transmission. While the committee is not aware of literature showing this as an important route of transmission, the SSRA should be thorough and also address the risk of transmission to cattle in the Manhattan, Kansas area due to the contamination of respiratory tracts of workers.” The SSRA did not address those issues. Staff and Personnel Training Staffing and training of staff is a large subject, some of which will only be described later in the process of bringing the NBAF online. However, with regard to scientific excellence and public service, one key aspect that will contribute to the NBAF’s success will be the quality of its senior staff. It is not too early to acknowledge the need to develop more detailed recruiting, retention, continuing education, and career development plans. Given that the NBAF is in its early planning phase, it will be important to elaborate on staffing plans more than the current version of the SSRA document does, especially if human error may be the most likely hazard of concern. Whereas the SSRA estimates roughly 300 staff members in the NBAF, it does not mention site-specific risks associated with staffing. A proper assessment will need to provide much more detail about staff composition other than the numbers in each specialty laboratory, such as consideration of their experience, national disciplinary standing, reputation, expertise, and other personal qualities required for working in high-containment settings. The matter is amplified by the intent of the NBAF to work with zoonotic pathogens in large animal facilities, a new capability for the United States. The SSRA noted that human error is the most likely cause of laboratory-acquired infection or release of a pathogen (via various scenarios), so it is imperative that laboratory workers receive the best training available. The NBAF will also inevitably expand its mission to move further into the modern world of molecular virology, molecular immunology, molecular pathogenesis and pathophysiology, molecular vaccinology, and therapeutics—fields of biomedical science from which disease prevention and control strategies are to emerge. Federal and International Regulations It is expected that further federal regulations, guidelines, or standards are forthcoming regarding the qualification, certification, or accreditation of staff who work at BSL-3 and BSL-4 containment levels. Work with zoonotic agents at the NBAF will need to conform to biothreat agent regulations, such as the Select Agent Rule, and other future regulations regarding biothreat agents will need to be anticipated. In addition, U.S. scientists and technicians will need to be trained to conduct work that is internationally regulated by the World Organisation for Animal Health. Hence, DHS will need to outline steps that enable the NBAF to be fully equipped to handle internationally-regulated diagnostics from day one. Subject Matter Experts Like other world reference laboratories, the NBAF will need world-class subject matter experts to be integral in the training process. Subject matter experts are well aware of current research, developments, practices, and thinking in the international community, and such

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EVALUATION OF THE NBAF SITE-SPECIFIC RISK ASSESSMENT 56 knowledge will provide staff with a critical understanding of each disease and disease agent to be studied at the NBAF. REFERENCES AS/NZS (Australian Standard/New Zealand Standard 2243.3). 2002. Safety in laboratories – Microbiological aspects and containment facilities. Australian Standard/New Zealand Standard 2243.3. CDC (Centers for Disease Control and Prevention). 2009. Biosafety for Microbiological and Biomedical Laboratories. Fifth Edition. Available online at http://www.cdc.gov/biosafety/publications/bmbl5/BMBL.pdf [accessed July 26, 2010]. Mani, P., and P. Langevin (eds.). 2006. Veterinary Containment Facilities, Design and Construction Handbook. International Veterinary Biosafety Working Group. Available online at http://www.vetbiosafety.org/history.html [accessed September 7, 2010]. Public Health Agency of Canada. 2004. Laboratory Biosafety Guidelines 3rd Edition. Available online at http://www.phac-aspc.gc.ca/ols-bsl/lbg-ldmbl/ [accessed September 7, 2010]. Sellers, R.F., A.I. Donaldson, and K.A.J. Herniman. 1970. Inhalation, persistence, and dispersal of foot-and-mouth disease virus by man. J Hyg (Lond) 68(4):565-573. Sellers, R.F., K.A. Herniman, and J.A. Mann. 1971. Transfer of foot-and-mouth disease virus in the nose of man from infected to non-infected animals. Vet Rec 89(16):447-449. UK-HSE (United Kingdom Health and Safety Executive). 2006. Biological agents: The principles, design, and operation of containment level 4 facilities. Available online at www.hse.gov.uk/pubns/web09.pdf [accessed September 7, 2010]. USDA-ARS (U.S. Department of Agriculture, Agricultural Research Service). 2002. Facilities Design Standards, 242-1-ARS. Available online at http://www.afm.ars.usda.gov/ppweb/pdf/242-01m.pdf [accessed September 7, 2010].