The benefits of enhanced facility safety warrant concerted efforts to develop the data bases, analysis methods, and institutional incentives needed to foster broader use of risk analysis. Risk analysis procedures foster a useful way of thinking about how mission effectiveness, public health, safety and monetary investments may be threatened by facilities' failures to perform as anticipated. Risk analysis also can improve the allocations of resources to achieve more balanced reductions of risks at all stages of the building process, from early planning through continuing operations and maintenance.
The traditional body of standards and design criteria embodied in building codes and other documents endorsed by governments or professional organizations bear the primary burden of protecting the health and safety of people in and around buildings. These standards and criteria have, for the most part, been developed and refined through years of experience, and greater attention is sometimes focused more on some hazards than on others. There is no means for judging the overall risk to which facility users are routinely exposed, or the levels of safety that might be achieved through a more balanced effort.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations 5 FINDINGS AND CONCLUSIONS The benefits of enhanced facility safety warrant concerted efforts to develop the data bases, analysis methods, and institutional incentives needed to foster broader use of risk analysis. Risk analysis procedures foster a useful way of thinking about how mission effectiveness, public health, safety and monetary investments may be threatened by facilities' failures to perform as anticipated. Risk analysis also can improve the allocations of resources to achieve more balanced reductions of risks at all stages of the building process, from early planning through continuing operations and maintenance. BUILDING SAFETY AND RISK The traditional body of standards and design criteria embodied in building codes and other documents endorsed by governments or professional organizations bear the primary burden of protecting the health and safety of people in and around buildings. These standards and criteria have, for the most part, been developed and refined through years of experience, and greater attention is sometimes focused more on some hazards than on others. There is no means for judging the overall risk to which facility users are routinely exposed, or the levels of safety that might be achieved through a more balanced effort.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations Formal risk analysis, in contrast, seeks explicitly and within a common framework to assess threats springing from a variety of hazards. Engineering risk analysis principles and procedures have evolved primarily within the nuclear power and defense industries to assist decision-makers faced with difficult choices involving rare events with serious consequences. These principles and procedures may be applied to help public officials, design professionals, and other decision-makers responsible for managing resources to achieve facility safety as well. The committee noted that the nuclear industry and structural community have adopted probabilistic or risk-based methods for facilities design and management (PRA and LRDF, respectively, as noted in Chapter 3 and Appendix B), and perhaps other terms will be forthcoming to describe applications in other limited fields. The committee encourages broader adoption of a common terminology and broader application of such methods to multiple hazards in and around buildings. AN ANALYSIS PROCESS The committee highlighted nine specific areas, discussed in Chapter 4, in which risk analysis procedures may be applied at various levels of sophistication and detail to support more effective risk management: (1) design and operations of individual high risk facilities, (2) quality control and enforcement of codes or design criteria during construction, (3) facility operations and management activities, including monitoring of facility use, (4) facility maintenance, (5) retrofit strategies for dealing with newly identified hazards, (6) strategy for responding to hazardous events such as fire, severe storms, earthquakes, landslides, and flooding, (7) refinement of building codes and design guide criteria, (8) evaluation and certification of new materials or technologies, and (9) public decision-making about standards, codes, and project approvals. A five-part process should be followed to apply risk analysis in any of these areas: Identify the elements of facilities' design, construction, operation, maintenance, environment, and use that are sources of risk. Characterize these hazards in terms of events, and possible outcomes and consequences. Estimate—to the extent practical—the probabilities of occurrence of these hazards, again considering events, outcomes and consequences. Collect the data required to support these estimates of probability and descriptions of hazards.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations Involve the public through effective communication and appropriate participation in decisions about risk reduction and levels of achievable safety. The individual steps are not strictly sequential and, to some extent, all parts of the process proceed in parallel. Public involvement will help to define the sources of risk and the nature of these hazards, particularly with regard to the operations and maintenance actions and the role of human error. Estimation of probabilities and collection of data are also related. Preliminary estimates of probabilities may be used to determine what data will be most effective in sharpening subsequent estimates and resulting conclusions. The uncertainty of final conclusions can be progressively reduced (although never eliminated) until the marginal improvements no longer warrant added costs for data collection and analysis.39 Federal agencies that have both responsibility and authority to take action to ensure efficient use of the public's resources should adopt this risk-based approach to establishing their facilities planning and design criteria, procedures for quality assurance during construction, operating policies, and maintenance practices. These agencies' actions will then also demonstrate leadership to encourage private codes and standards organizations to work more rapidly toward balanced efforts for maximum achievable safety. BROADER USE OF RISK ANALYSIS Broad use of risk analysis is limited by available data and the cost of data collection. However, simplified analysis methods and existing data can support explicit risk analysis, based primarily on professional judgment, that can enhance overall risk management effectiveness. Government agencies and the private sector should implement the following recommendations: Government agencies, model code organizations, building professionals, and others responsible for ensuring facility safety should work to increase their own and the public's awareness of how risk analysis principles and practices can improve safety at reasonable costs. Professional education and training in risk analysis should be important elements of this effort, but informing facility owners and users is needed as well to assure that a balanced approach to all aspects of risk management is maintained. Engineers, architects, government officials and policy-makers, model building code 39 This process, widely used in business, is termed Bayesian decision theory. It is named for Bayes' mathematical theorem of conditional probabilities, upon which the procedure is based.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations organizations, professional societies and industry groups, universities, and the news media all have important roles to play. An especially perplexing challenge is finding means to facilitate public dialogue about acceptable levels of risk. Risks can be reduced to very low levels, but cannot be completely eliminated, and those risks associated with particularly dreaded consequences often generate highly emotional debate in public forums. Building professionals and public policy officials should work to inform the public on matters of facility risk, to identify public concerns, and to incorporate these concerns into balanced, cost-effective strategies for risk management. To increase safety and reduce costs, risk analysis should be incorporated selectively into federal agency facility design criteria and state and local building codes. Codes and formally stated design criteria will remain the primary means for assuring that safety and public health are protected in facilities. Agencies and private groups should work to develop risk-based standards for these documents. While thorough risk analysis is not practical for all facilities, specific application of risk analysis procedures should be required for facilities where large numbers of people, especially severe hazards, or unusual design or operating characteristics may lead to unusually high risk. Unusually high economic or strategic value of the facility or its contents would also warrant explicit risk analysis. Facility managers and responsible public officials should adopt risk analysis principles and procedures to ensure that a) operating and maintenance practices or facility renewal activities do not contribute to increasing risk, and b) needed actions are taken to control newly recognized risks. Decisions made during planning and design to control risk rely on actions assumed to be taken in subsequent construction, operation, and maintenance of the facility. Sometimes these actions are neglected (e.g., deferral of maintenance), operating conditions change (e.g., new uses of a facility), or new information (e.g., discovery of a new health hazard) indicates that unforeseen action is needed to keep risk at an acceptably low level. Achieving consistently high safety while avoiding unnecessary costs requires attention to risk throughout the service life of the facility. Mechanisms should be established to foster systematic collection of the data required for comprehensive analysis of facility risk. Government agencies, professional organizations, and the insurance industry are potential beneficiaries of increased use of risk analysis for facilities, and could jointly maintain these data. Investigations of significant facility failures should be made systematically within a common framework, indexed and analyzed to be available to code development bodies, design professionals, and the public. Establishment of an agency or private organization (perhaps similar to the National Transportation Safety Board) may be the most effective way to assure development of a comprehensive data base for facility risk analysis, but
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations individual agencies can start the process by pooling data within common reporting formats40. Research and development efforts should be accelerated to characterize risks associated with all phases of a facility's service life, and to find effective ways of communicating about this risk to support realistic public judgements about appropriate costs of risk management. Facility risk is influenced by actions taken in planning, design, construction, operation, maintenance, and renovation or retrofitting of obsolete systems. Work is needed to develop analysis techniques and monitoring systems that support continuing assessment of risk at all these stages. Government agencies, as a group the nation's largest builder and custodian of the public's built assets, should take leadership, working closely with universities and industry. Early action should be taken on these recommendations. The benefits to be gained include better allocation of resources to achieve balanced reduction of risks; better recognition of the role that human action plays in raising or lowering risks through design, construction, operation, and maintenance; and improved ability to recognize and respond to new hazards or increasing risk. Taken together with the committee's broader recommendations presented in preceding chapters, the benefits can be realized by the industry as a whole and, consequently, by the nation. For facility owners, occupants, and neighbors these benefits of enhanced safety and protection through broader use of risk analysis will result in lives and dollars saved. 40 Studies sponsored by the FCC have pointed the way toward development of integrated data bases for buildings that could include performance data to support risk analysis.
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