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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations 4 OPPORTUNITIES FOR ENHANCING SAFETY AND PROTECTING VALUES While current lack of data and the distribution of responsibilities for safety among many agencies represent obstacles to effective use of risk analysis, opportunities for improving safety are substantial. Peoples' lives, health, and property can be protected more effectively through broader application of risk analysis. AREAS OF OPPORTUNITY Nine phases in the facility life cycle represent particular opportunities for application of risk analysis to enhance achievable safety. Risk analysis can be used as a decision-making tool in the design and operations of certain facilities, particularly those which may (a) expose large numbers of people or especially sensitive property to hazards (e.g., sports stadiums, museums, or certain military installations), or (b) be subjected to especially severe or dreaded hazards (e.g., large power plants, medical research laboratories, or facilities housing or employing significant quantities of toxic materials), or (c) involve novel and largely unknown but potentially high risk building technology (e.g., large scale prototype applications of new materials or design methods). Risk analysis procedures are likely to be too
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations costly and time consuming—in comparison to the possible incremental improvements in risk management—to be usefully applied to all facilities, but in special cases a separate risk analysis may be warranted. Risk analysis can be used by agencies and other facility owners to guide quality control and code enforcement in construction. Serious losses associated with human error and faulty practices during construction indicate that facility owners, insurers, and code officials should press for greater attention to the impact on safety of constructable designs, preparation of clear and unambiguous plans and specifications, and construction inspection. Risk analysis can serve as a framework for estimating this impact, guiding quality control and assurance efforts, and assuring that risks are not unnecessarily increased by actions taken during construction. For similar reasons risk analysis can be used to guide facility operations and management activities. Personnel responsible for these activities are often unaware of how critically safety depends on a facility's operating systems being used according to the designer's intentions. Budget constraints, time expediency, or simply lack of understanding may motivate changes in occupancy, furnishings, and operating procedures that then sharply increase risk, as outbreaks of legionnaires' disease have demonstrated.31 Risk analysis may guide operations and management procedures to assure that attention is placed where it matters most to safety. Monitoring of facility use can be an important element of this application, to determine when occupants' activities may be reducing safety. Facility maintenance—which should include monitoring of condition and performance—may be the most neglected factor in managing risk. The individuals responsible for the physical aspects of maintenance seldom have full control of resources needed to support their activities, and underfunding is a chronic problem.32 The collapse of corroded bridges has demonstrated that the consequences of deferral and neglect of maintenance, sometimes slow to become apparent, can accumulate with serious consequence. Risk analysis can be used to characterize the effects of maintenance or its neglect, by drawing valid general conclusions from the individual rare events of facility systems failures. 31 Failure to clean filters in heating, ventilating, and air conditioning systems has been cited as contributing to outbreaks of legionnaires' disease and other respiratory illness among building occupants. 32 Another BRB committee addressed this issue in their report Committing to the Costs of Ownership, National Academy Press, Washington, D.C., 1990.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations Building professionals can use risk analysis to develop retrofit strategies for dealing with newly identified hazards. For example, reported cases abound where the techniques used to remove asbestos increased the risk of exposure, and the committee noted the concern expressed by industry that new regulations to deal with lead-based paints could produce similar results. Risk analysis can help establish rational policies in these situations. Risk analysis can be used to develop effective strategies for responding to hazardous events such as fire, severe storms, or landslides. The analyses would encompass maintenance readiness, advance warning, and allocation of resources for immediate response. Risk analysis also provides a framework for reasoned adoption of change in building regulations that may be justified by the new evidence gained from a disaster. Local governments, in particular, might benefit from general guidance, based on risk analysis, regarding when changes in local building codes are or are not warranted. The process for developing building codes and design guide criteria in the United States, an already effective means for achieving safety, would be strengthened by greater application of the principles and practices of risk analysis. Probability-based structural design criteria and new work on fire safety (particularly in Canada33) warrant greater application. Risk analysis is ideally suited for evaluating and certifying new materials or technologies. Systems for approving new building products approval systems are similar in principle to the system used for food and drug regulation. However, there are more than 50 different U.S. product approval systems (FCC, 1990) and few common criteria for judging safety. Risk analysis can provide a common framework for evaluation to support decision-making. Risk analysis can support public decision making about standards, codes, and projects. While perceptions of risk vary from person to person and among groups of people, the process of assessing and judging risk seems to enhance the public's ability and willingness to make informed decisions about difficult questions involving risk. More effective communication regarding the risks in and around buildings and the costs of limiting these risks will help public policy-makers to respond appropriately to demands for action following serious losses. 33 The Province of Ontario, for example, has undertaken a review of the cost-effectiveness of all code requirements, and the National Research Council of Canada is developing a risk-cost assessment model for apartment buildings.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations OVERCOMING LACK OF DATA FOR RISK ANALYSIS These nine areas of opportunity are specific instances where greater use of risk analysis has the potential to enhance achievable safety. However, the barriers to this greater use must be overcome for the potential to be realized, and lack of data is the first of these barriers. One key reason for lack of data is simply the rarity of facility failures from events such as very strong earthquakes, major fires, and other significant hazard events. When these events do occur, they are too seldom observed and measured in a careful way that supports development of a data base for subsequent use by designers and risk analysts.34 For only a few types of hazard are data on similar events occurring in different locations consolidated and systematically compared to support a more general analysis of risk in and around buildings. Data on facilities' characteristics that influence risk are similarly sparse because regular condition assessments of facilities are rarely available to support analysis when failures occur. In addition, performance of new materials and facility systems must be estimated from theoretical analyses, laboratory tests, or limited field observations that may not reflect the range of conditions likely to be encountered in practice. The insurance industry has considerable data on loss experience, but these data are related primarily to dollar losses and industry rate classes, and are poorly suited to risk analysis as discussed here. The industry has developed technical information on how to reduce fire-related and certain other risks in and around buildings, but depends largely on judgment to interpret the degree to which risk is likely to be reduced. Loss experience, a part of the basis for this judgment, depends on costs and a variety of factors not directly related to technical risks. In contrast to the focused roles of agencies such as the Nuclear Regulatory Commission, the National Transportation Safety Board or the Food and Drug Administration, there is no national regulatory focus for data gathering and analysis of the broader range of building-related risks. The Environmental Protection Agency, the Federal Emergency Management Agency, and the Occupational Safety and Health Administration are among those agencies having some interest in this area, but these agencies' concerns are not focused on facility risks. 34 Analysis of earthquakes may be the most advanced of the principal environmental hazards. Records of ground motion in major earthquakes are available to researchers for detailed study of patterns of damage in the areas where the earthquake occurred. (NRC, 1988)
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations Some ten years ago, an attempt was made to establish building risk clearinghouse at the University of Maryland. The Architectural and Engineering Performance Information Center started there was never able to attract adequate support, and is not currently active. The National Research Council of Canada undertook to establish a similar effort that also failed to gain momentum. Professional associations and model building code organizations may partially provide the focus for data base development. For example, the ANSI A58.1 standard on design loads35 provides a basis for designing typical or average facilities, but offers little information for designing unusual facilities, or for dealing with safety issues related to low-probability hazards. Government agencies also might play a role in fostering necessary data collection. For example, the Building Research Establishment in the United Kingdom maintains information on failures in buildings and publishes a series of Defect Action Sheets intended to alert the profession to newly understood defects that may be avoided or mitigated. Such a system could be established in the United States as a federal agency such as the National Institute for Standards and Technology. Lack of generally available data can make analyzing the safety of an existing facility time-consuming and costly. Architectural and engineering plans for existing facilities, especially older facilities, may not be up-to-date or even available. Obsolete materials and construction methods may be unfamiliar to current designers or risk analysts. Hence, a thorough condition assessment and extensive load testing may be required simply to assess the physical characteristics of the facility.36 Use of risk analysis may, then, effectively be limited to those facilities where the financial investment and numbers of people exposed to the hazard warrant the cost of data collection. On the other hand, agencies such as the Department of Energy, the Federal Emergency Management Administration (FEMA) and the U.S. Army Corps of Engineers have developed procedures for assessing flood and earthquake hazards at particular locations, and for shaping design decisions 35 American National Standards Institute. 1982. American National Standard Minimum Design Loads for Buildings and Other Structures. New York. 36 Committee members estimated that current costs for risk analysis in an existing building might typically be in the following range: $30,000 for data collection and load testing for assessment of structural safety in reuse of an older building, and $5,000 for a largely judgement-based analysis of fire hazard in a moderate-sized office building. However, many factors will influence actual costs in any particular situation.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations that influence subsequent risks at these locations. The General Services Administration (GSA) has undertaken training programs to inform their staff about the procedures of risk analysis, and principles of risk assessment are reflected in the agency's safety and environmental management programs (Events Analysis, Inc, 1989; GSA, 1988). Such currently active data collection programs as the National Fire Incidence Reporting System, activities administered by the Consumer Product Safety Commission, the National Safety Council, and the Occupational Safety and Health Administration, and loss reporting activities of agencies such as the Navy, Department of Energy, and General Services Administration could be combined or expanded to support comprehensive risk analysis. The growing experience with such programs may support the research needed to develop more general measures of hazard and risk. Federal agencies should share their own experience in this area, and should fund research and encourage the private sector to use this experience as a basis for developing the measures needed for more general risk analysis. MOBILIZING FOR RISK ANALYSIS Even with adequate data, changes are needed in the nation's system for managing risk before the resources of government and industry can be effectively mobilized to use risk analysis. Technical understanding in the building industry has achieved high levels, but facility design and operations still involve the judgement of trained professionals. Furthermore, any complete set of criteria and standards to deal with all risks at all levels would be too costly to apply. However, federal regulatory and construction agencies acting in cooperation with the insurance industry can capture benefits of applying risk analysis, and should join to foster the institutional focus needed for progress. The Federal Construction Council should continue this effort by bringing together these federal agencies, the insurance industry, and the national building codes and professional organizations that deal with building standards, to focus their combined attention on how to implement broader application of risk analysis. In addition, building professionals should be prepared in the future to use risk data and make judgements about relative safety. Preparation begins with professional education, and the committee recommends that principles and practices of risk analysis be made part of the training received by architects, engineers, and code officials. Texts already have been developed that could be used to introduce information on risk analysis into both university courses and continuing education programs.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations COMMUNICATING WITH THE PUBLIC The levels of safety that can be achieved in practice depend on the public's willingness to allocate resources and undertake the actions required to manage risk in and around buildings. The aim of building designers and managers should always be to make facilities as safe as possible within the constraints of available resources, current technology, and the public's willingness to act.37 Current public attitudes toward avoiding risk make it essential that the cost of being wrong—including legal liability as well as physical consequences of underestimating hazard severity or likelihood—should be explicitly considered. The potential for intense public debate may deter government decision-makers from addressing these costs within their usual administrative and political forums. A formal procedure to raise this issue may be warranted for major projects involving high potential hazard. Experiences from three decades of environmental impact review, show that the manner in which risk analysis is performed in many cases may be as important as the result. People must develop confidence in the process that leads to a decision when they are unable to judge for themselves the qualify of the information used in the process. The reputation and professional standing of people involved in the process becomes very important to building that confidence. Furthermore, public attitudes are influenced, in part, by our increasing ability to identify and measure the intensity of hazards that may previously have escaped detection. Newly identified risks that are poorly presented may foster public dismay and hasty responses that can distort public policy and regulatory practice.38 Taxpayers and voters may lack a broadly understandable baseline against which to judge acceptable risk and achievable safety. 37 Legal liability sometimes makes policy makers and facilities managers reluctant even to consider that some level of risk is unavoidable and acceptable. Because there is little basis in everyday experience for assessing the significance of very low probabilities, discussion of achievable safety is likely to be controversial and difficult to conduct in a public forum. Sound risk analysis and thoughtful risk communication programs, however, can help to overcome this difficulty. 38 The opposite effect may also occur. The EPA estimates radon gas to be a significant source of cancer risk in many parts of the country, yet has been unable to mobilize broad public support for regulation.
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Uses of Risk Analysis to Achieve Balanced Safety in Building Design and Operations Comparisons of estimated risk in different contexts (for example, risk of death due to highway accidents versus cancer attributed to a particular drug) are often misleading. Care must be taken to avoid letting illustrative examples become standards for judgement. Nevertheless, ''code equivalency''—the levels of risk implicitly accepted for those hazards addressed in building codes—may be a useful baseline for judging levels of risk for other hazards in and around buildings. The same baseline may be useful to federal agencies not subject to local codes but seeking to determine if their design criteria are maintaining risks at acceptable levels. A risk analysis of model codes could produce estimates of what these baseline levels of risk are. Analysts and decision-makers involved in risk analysis for a particular action (i.e., construction or reuse of a particular facility, or adoption of a new regulatory policy) must recognize that public debate may initially be stimulated as possible hazard events and outcomes are identified. Interested people will seek to assure a common understanding of probabilities and the relative desirability of these possible consequences. The public participates, in principle, in the current process of establishing building codes and the institutional arrangements that support the code process, but this participation is not consistently effective. The work of the principal national model codes organizations is generally open to public involvement, but building code officials and building products manufacturers are currently the principal participants in those forums, and code changes often are proposed by trade associations and may have economic motivations. Similarly, adoption of official local building codes typically entails public hearings, but the general public often is poorly prepared to deal with the technical issues of facility design and construction. Nevertheless, there seems generally to be a high level of public confidence in the ability of the design professions and the regulatory process to control risk. Applications of risk analysis should meet highest professional standards to avoid threatening this public confidence. Experience in other fields illustrates that good public communication is essential. Serious concerns about the siting of hazardous and municipal waste disposal facilities are heightened by people's perception that they are being given incomplete information and being excluded from the decision-making process. A sound risk communication program can help to avoid such exaggeration (NRC, 1989).
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