Society is changing ever faster, and tunnels are complex systems where performance is affected by many different stakeholders. This suggests that safety management needs to be proactive and based on a systems perspective that acknowledges socio-technical systems theories. Although systems thinking principles are foundational in overarching goals and European regulation, system principles are generally not affecting tunnel fire safety design principles or engineering practice. In the countries investigated in this study, tunnel fire safety management (TFSM) builds on experience-based and risk management-based principles that optimize independently system by system. This is usually done with limited consideration of how these systems are interconnected and affect the overall tunnel system. The purpose of this paper is to investigate rules and engineering practice against the assumption that systems thinking could support existing engineering practice. The work presented in this article is the outcome of a collaboration between fire safety researchers and practitioners from five different countries and three different continents. Through three workshops, current TFSM have been compiled and discussed. To improve the situation, the authors suggest to re-design tunnel safety regulations and to strengthen engineers’ ability to work in design teams using systems thinking principles.

Fire has the potential to create significant impacts on the built environment. Managing this impact is sometimes pursued without consideration of the interface between the natural and technological worlds. However, as society has recognized the impacts of technological development on environmental sustainability, the need for sustainable and resilient development has emerged. To facilitate sustainable and resilient development, technological choices should embrace a sociotechnical systems approach that considers the interactions of society, technology and institutions, and their interactions with the environment. Failure to do so can result in unintended consequences. Society's technological choices aimed at increasing sustainability of buildings, such as the desire to reduce building carbon footprints or improve the use of renewable energy systems, can have significant impacts on fire resilience if not considered holistically. To better understand and comprehensively address and mitigate intolerable fire risk associated with choices driven by sustainability objectives, a balanced and holistic systems approach is needed. To this end, a framework to foster a systems-oriented approach to improving both sustainability and fire resilience, in tandem, to create a Sustainable and Fire Resilient Built Environment (SAFR-BE) is presented.

Considerable cost and effort are invested in government and private-sector activities aimed at providing a societally tolerable level of fire safety of the built environment. This is particularly true with respect to fire safety of new building construction. On the government side, this includes activities associated with building and fire regulations, material performance and test standards, design guidance, competency requirements, review and approvals, and more. On the private side, activities include product development, analysis and design, construction and installation, as well as education and training of practitioners. In some cases there are overlaps (e.g., private building control). However, once buildings become occupied, the system faces several challenges. Oversight of building use and modification often gets lost. Different actors come into play. Competing objectives become more significant. Occupants often lack understanding and ability to recognize problems and make adjustments. The net result is an increase in fire safety risk over the life of a building, with less opportunities for the regulatory system to make interventions prior to an unwanted fire event. However, this can be changed if the approach to regulating existing buildings changes, and importantly, embodies whole-of-life, multi-agency, holistic, systems-based thinking.

The fundamental construct for performance-based design for fire safety in use today has not significantly changed since the early 1990s. While the current construct has seen some success, performance-based design for fire safety is not as broadly accepted as performance-based design approaches in other building-related engineering disciplines. To advance performance-based design for fire safety, it is proposed to move towards a sociotechnical systems approach. This means changing the starting point from a focus on fire safety objectives as a unique property of buildings, infrastructure, or operations, and considering fire safety as one of several sociotechnical objectives. It also means focusing fire safety analysis and design on system attributes which can be controlled through design, and less on variables for which control is unlikely or not possible. As part of this, consideration of fire safety systems performance should be considered in terms of a 'fail-safe' perspective, in which there is less focus on all possible events that could occur, and more on preventing those which could result in unacceptable performance. Evaluation of building fire safety as a sociotechnical systems problem would also need to consider the interactions of all components that contribute to safety over the lifetime of the system, including in-use safety system management and system performance over time.

A building performance gap may exist in each building area. While performance monitoring tools are available and widely applied in energy efficiency and structural health, there are currently no available performance monitoring tools in the area of fire safety. Although a fire accident is an acute phenomenon that is rare and unpredictable and makes observing a building's fire performance very difficult, the evolution of underlying factors that determine the building fire performance in a future fire is in fact a chronic phenomenon that is observable and predictable. This article proposes a sensitivity matrix method (SMM) based on Taylor series expansion to better understand the building fire egress performance gap by analyzing changes in chronic influencing factors. Uncertainty of this method is investigated against FDS simulations in an exemplar 3-story apartment building and described by two parameters: the system bias and the relative standard deviation. Combining the available safe egress time (ASET) with the required safe egress time (RSET), the resulting Egress Safety Ratio (ESR) is chosen as the key building fire egress performance indicator in case studies, and a prototype fire performance monitoring tool based on the SMM is developed, indicating its potential of tracking and closing the building fire egress performance gap.

Modern methods of construction (MMC) are becoming increasingly popular for a broad range of reasons. They are portrayed as providing significant economic and sustainability benefits over ‘traditional’ construction methods, 'e.g'. efficiencies gained by integrating the processes and technologies of design, manufacturing, and construction to result in higher quality buildings. It may also include a reduction in delivery times, more predictable costs, and fewer environmental impacts. However, MMC introduces increased complexity and can present challenges for traditional building regulatory approaches, especially those which focus on inspecting and verifying construction at many points in the construction process. With prefabricated components and modules this requires different approaches. Performance concerns arise for meeting the fire safety objectives of the final building. One particular fire challenge is the presence of void spaces, often needed to facilitate the connection of modules, which can potentially serve as avenues for the spread of fire, smoke, and hot gases. These fabrication issues, performance concerns, and regulatory challenges are explained. Fire performance issues are then explored for different regulatory typologies (prescriptive, performance based, market based), the verification of subsystem performance, and the compliance of installed components/whole building. Recommendations for regulatory frameworks are provided to provide increased confidence and reduced risks. 'Policy relevance' While every country needs to work within their regulatory framework and implement systems that work for them, it seems that with the growing use of MMC, additional regulatory guidance and oversight may be warranted to help increase confidence in the performance of modular buildings, in particular from a fire performance perspective. This might include the development of design and installation guidance, as well as regulatory review, inspection, and approval guidance. It may also mean the development of new test methods or standards, especially if materials or connection conditions ('e.g'. void spaces) warrant. As many countries have already mandated, it seems that the requirement for some form of quality assurance/quality control (QA/QC) procedures to help assure manufactured/fabricated components comply with regulatory requirements is an essential component.

The environmental impact of fire in buildings, structures and facilities can be mitigated by preventing fires, managing the size of fires if they occur, or managing the exposure to the environment. This can be accomplished using a variety of prevention and mitigation measures, from controlling of potential sources of ignition, containment of fire spread, suppression or extinguishment of fire, and control of any firefighting runoff. Approaches to fire mitigation can be found in regulatory documents, consensus standards, handbooks and guidelines that span the range from fire safety engineering to environmental protection. This chapter presents a brief, high-level overview of the range of potential measures to prevent or mitigate the impact of building, structure and facility fires on the environment. Sources for more detail treatment of the various topics is provided.

Fire impacts to the environment come from both natural and human-caused sources. Managing both often requires different strategies, and can be pursued without consideration of the interface between the natural and technological worlds. However, as society has looked to minimizing the impact on the natural world by implementing sustainability strategies, and more recently has recognized the need to make human settlements resilient as well as sustainable, the need to create sustainable and resilient human development has emerged. When one further considers the interrelationships between carbon emissions, climate change and climate impacts, this need becomes imminent. While this is true for many hazards, fire is a particular hazard of concern, since fire as a natural hazard is being increased in frequency and intensity by changes in climate that are increasing drought conditions and high temperatures, and fire as a technological hazard can be inadvertently increased by implementation of energy sustainability measures, such as localized energy sources (e.g., photovoltaics) creating potential ignition hazards, and thermal insulation (specifically combustible materials) creating additional fuel load. In order to most comprehensively address and mitigate the increasing fire risk is to adopt the concepts of a Sustainable And Fire Resilient Built Environment (SAFR-BE), where the built environment includes buildings (structures, facilities), infrastructure and communities. This chapter introduces the concept of SAFR-BE and how such holistic thinking can be applied to reduce environmental and other impacts of fire.

There exist many handbooks that offer technical explanations and guidance on fire safety design and on safeguarding the environment, but not the combination. This handbook presents an introduction to fire, its impacts on the environment, and strategies for mitigating both fires and their environmental impacts. It presents examples of significant environmental impacts associated with fire and firefighting, some basics on the chemistry and physics of fire, and means to predict fire and smoke development and spread. The scale considers a range from individual buildings to wildland fires. Means to measure fire effluent and estimate fire impacts on the environment are overviewed, and mitigation strategies across the scale of fires is introduced. This chapter provides a brief introduction to the impact of fire on the environment and to each chapter in the handbook.

Wildfires are an essential part of a healthy ecosystem, yet the expansion of the wildland-urban interface, combined with climatic changes and other anthropogenic activities, have led to the rise of wildfire hazards in the past few decades. Managing future wildfires and their multi-dimensional impacts requires moving from traditional reactive response to deploying proactive policies, strategies, and interventional programs to reduce wildfire risk to wildland-urban interface communities. Existing risk assessment frameworks lack a unified analytical method that properly captures uncertainties and the impact of decisions across social, ecological, and technical systems, hindering effective decision-making related to risk reduction investments. In this paper, a conceptual probabilistic wildfire risk assessment framework that propagates modeling uncertainties is presented. The framework characterizes the dynamic risk through spatial probability density functions of loss, where loss can include different decision variables, such as physical, social, economic, environmental, and health impacts, depending on the stakeholder needs and jurisdiction. The proposed approach consists of a computational framework to propagate and integrate uncertainties in the fire scenarios, propagation of fire in the wildland and urban areas, damage, and loss analyses. Elements of this framework that require further research are identified, and the complexity in characterizing wildfire losses and the need for an analytical-deliberative process to include the perspectives of the spectrum of stakeholders are discussed.

Fire safety provisions in building regulation are about managing risk. In order to appropriately characterize and incorporate risk measures into building regulation, it is helpful to view building regulatory systems (BRS) as complex socio-technical systems (STS), wherein there are interactions between institutions, technology and people, which ideally work together to mitigate risk to a societally tolerable level. A description of BRS as STS and how to assess the efficacy of the BRS in managing fire risk is presented. To illustrate how STS concepts can be used to evaluate and restructure a functional- or performance-based BRS, STS concepts are applied to the evaluation of the building regulatory system in England.

Unlike the areas of building energy and structural health, performance monitoring tools are currently absent in the area of building fire protection. Computational Fluid Dynamics (CFD) models like Fire Dynamics Simulator (FDS) are widely applied in building fire performance design, which can be equally used to predict changes of building fire performance. However, due to its time-consuming nature, it is not realistic to apply FDS frequently. The sensitivity matrix method (SMM) has been discussed as a quick method to predict changes of building fire egress performance. However, this approach can have significant uncertainties when being applied to datasets with many input parameters due to its inherent incapability of predicting accurately system responses if input data are considerably far away from the baseline points around which a SMM is developed. Response surface methods (RSM) are commonly used to characterize the relationships between input variables and output quantities for complicated problems. Different from conventional RSMs, a novel two phase power function fitting process is proposed to develop substitute algebraic models of the available safe egress time (ASET) from FDS numerical experiments based on a theorem which states that an output variable is proportional to the product of input parameters to their respective powers if the output variable is proportional to each input parameter to some power and the input parameters are independent of each other. An artificial neural network (ANN) is a universal method to approximate any arbitrary complicated, nonlinear system response with limited number of discontinuities without deep understanding of how the system works. This paper employs MATLAB's feedforward neural networks with error backpropagating algorithm to approximate the FDS response. Applicability in terms of uncertainties including system bias and relative standard deviation (RSD) or percentage of predictions falling in a preset acceptable error range are compared among RSMs developed from various datasets, ANNs with various hidden layer sizes and dataset sizes, and SMMs which use the same fire scenarios in a small three-story apartment building. The result shows that it is possible for ANNs to have lowest model uncertainties and highest percentage of predictions within the preset 20% error scope as far as the specific fire egress safety problem discussed in this paper is concerned, but the cost of developing a SMM, namely the number of data cases, is the lowest. Due to the different aspects of RSMs, ANNs, and SMMs, to better understand the building fire performance gap continuously, a hybrid strategy of starting with SMMs followed by RSMs and/or ANNs is recommended in a fire performance monitoring tool.

There is a trend in Europe towards increasing the quality and performance of regulations. At the same time, regulatory failure has been observed in the area of building fire safety regulation in England and elsewhere. As a result, an analysis of the appropriateness of fire safety regulations in Spain is warranted, with the objective being to assess whether a suitable level of fire safety is currently being delivered. Three basic elements must be considered in such analysis: the legal and regulatory framework, the level of fire risk/safety of buildings that is expected and the level which actually results, and a suitable method of analysis. The focus of this paper is creating a legal and regulatory framework, in particular with respect to fire safety in buildings. Components of an ”ideal” building regulatory framework to adequately control fire risk are presented, the existing building regulatory framework is summarized, and an analysis of the gaps between the ideal and the existing systems is presented. It is concluded that the gaps between the ideal and the existing framework are significant, and that the current fire safety regulations are not appropriate for assuring delivery of the intended level of fire risk mitigation.

To advance understanding of the multihazard performance of midrise cold-formed steel (CFS) construction, a unique multidisciplinary experimental program was conducted on the Large High-Performance Outdoor Shake Table (LHPOST) at the University of California, San Diego (UCSD). The centerpiece of this project involved earthquake and live fire testing of a full-scale 6-story CFS wall braced building. Initially, the building was subjected to seven earthquake tests of increasing motion intensity, sequentially targeting service, design, and maximum credible earthquake (MCE) demands. Subsequently, live fire tests were conducted on the earthquake-damaged building at two select floors. Finally, for the first time, the test building was subjected to two postfire earthquake tests, including a low-amplitude aftershock and an extreme near-fault target MCE-scaled motion. In addition, low-amplitude white noise and ambient vibration data were collected during construction and seismic testing phases to support identification of the dynamic state of the building system. This paper offers an overview of this unique multihazard test program and presents the system-level structural responses and physical damage features of the test building throughout the earthquake-fire-earthquake test phases, whereas the component-level seismic behavior of the shear walls and seismic design implications of CFS-framed building systems are discussed in a companion paper.

It has been suggested that future generations of building regulation can become more risk-informed and performance based, and that this can be best facilitated through viewing the building regulatory system as a socio-technical system (STS). A central component of the STS approach to building regulation is that government (regulators) and the market understand and agree the risk measure(s) that have and will be used to define the tolerable level of risks that are addressed through building regulation, the specific risk criteria that will be used in the evaluation of the risks for regulation and design, and the analysis and design approaches that will be used to demonstrate that building design solutions can be verified as meeting the risk criteria and measures. To support these efforts, a risk characterization roadmap is presented as guidance for building regulators embarking on efforts to use risk as a basis for building performance requirements. While the roadmap has been designed to address all health and safety hazards considered within building regulations, characterization of fire risk is used as an example throughout.

Fire safety can be defined as the requirements that cumulatively guarantee the absence of conditions for fire ignition and also eliminate or minimize the effects of the fire on people and property. Based on this premise, we can assume that a fire risk assessment methodology is more effective as more components contributing to fire safety are integrated in the analysis process. In this paper a new fire risk assessment methodology is proposed, based in a holistic approach analyzes of the potential of failure of each of the critical components, that compete differently for the overall performance of the fire safety of the building. This methodology attempts to respond to the problems of the current risk analysis methodologies regarding their applicability—with identical reliability—in different types of buildings and fire scenarios. In order to reduce the level of uncertainty, as much as possible, the method uses a redundant fire risk estimation process. In one analysis dimension, the model uses the parameters of probability, severity and exposure of fire for valuing the risk in function of the failure potential of performance analysis indicators considered critical in relation to the variables of fire prevention and protection. It is compared an actual or potential performance with a standard performance considered as safe. In another dimension of analysis, the method determines the potential of fire growth and spread in function of the existing conditions in the building, to assess whether it is safe for its occupants, until the complete evacuation of the building.

The International Association of Fire Safety Science (IAFSS) is comprised of members from some 40 countries. This paper presents the Association's thinking, developed by the Management Committee, concerning pressing research needs for the coming 10 years presented as the IAFSS Agenda 2030 for a Fire Safe World. The research needs are couched in terms of two broad Societal Grand Challenges: (1) climate change, resiliency and sustainability and (2) population growth, urbanization and globalization. The two Societal Grand Challenges include significant fire safety components, that lead both individually and collectively to the need for a number of fire safety and engineering research activities and actions. The IAFSS has identified a list of areas of research and actions in response to these challenges. The list is not exhaustive, and actions within actions could be defined, but this paper does not attempt to cover all future needs.

The Interactive Performance Information (IPI) chart is the most important single tool for evaluating fire performance of buildings. The IPI chart organizes information, stores data, enables one to understand dynamic interactive behavior, and aids communication. This chapter describes the organization and introduces a few functions of the IPI chart in performance analysis and risk management. It first identifies the major components of a complete fire safety system. The chapter then shows the basic template organization for the IPI chart. Reading IPI charts can give an awareness of the strengths and weaknesses of a building. The main function of an IPI chart is to organize and display information. This information creates a performance understanding to guide rational decisions for improving or managing risks associated with an unwanted fire. The IPI chart integrates attributes of Gantt charts used in project management and computer-generated spreadsheets with the logic of systems analysis and risk management.