The Evaluation of a Performance-Based Design Process for a Hotel Building: The Comparison of Two Egress Models

This work emphasizes the importance for egress model users to choose a model for each project with the appropriate input features and simulation capabilities. This report also gives model users a mechanism for choosing the appropriate model by providing a detailed egress model review (Chapter 2). Specifically this report focuses on the ability of two egress models, EXIT89 and Simulex, to simulate a high-rise hotel building evacuation. When EXIT89 and Simulex are used to 1) simulate the same design scenarios and 2) perform a bounding analysis of the hotel building, significant differences in egress times were identified. EXIT89's evacuation times were found to be 25-40% lower than Simulex for the design scenarios, attributed to differences in unimpeded speeds, movement algorithms, methods of simulating slow occupants, density in the stairs, and stair configuration input between the models. For the bounding analysis, EXIT89 produced maximum evacuation times 30-40% lower than Simulex

Ember Alerts: Assessing Wireless Emergency Alert (WEA) Messages in Wildfires Using the Warning Response Model

When evacuation is necessary in a wildfire event, affected communities must be alerted and warned of the imminent danger and instructed on what to do to protect themselves. One channel available to message providers in the United States is Wireless Emergency Alerts (WEAs) disseminated via IPAWS. Recent wildfire events have shed light on the need to improve WEA strategies and messages when alerting exposed populations of imminent fire threat. The purpose of this article is to assess how, when and where WEAs have been used in US wildfires; whether they comply with guidance set out by Mileti and Sorensen’s Warning Response Model (WRM); and whether the expansion in characters (from 90 to 360) of WEA messages has influenced compliance with the WRM. A quantitative content analysis was conducted of WEA messages sent during US wildfires from January 2020-April 2022. A total of 1,284 messages were manually coded based upon the content and style categories identified in the WRM. Descriptive analyses (and Chi-square tests) were performed to illustrate how 90-character and 360-character WEA messages differ by key content and style features. Results showed that certain content features (i.e., location, guidance, and the name of the hazard) were included more often than others (i.e., source, hazard description, hazard consequences, and timing information) and that the inclusion of most content features increased with increasing message character length. Additionally, when assessing message ‘completeness’, the use of acronyms was prevalent in both 90- and 360-character wildfire WEAs; whereas the inclusion of URLs was linked to increased message length. Wildfire WEAs also displayed inconsistency both within and across states in their use of terminology to trigger evacuation. These findings, among others, have implications for theory highlighting a growing need to confirm that message receivers understand and can act on the messages sent, regardless of the language used. In addition, for message creators, recommendations for effective WEA messages for wildfires are provided

A review of post-incident studies for wildland-urban interface fires

Abstract Post-incident studies provide direct and valuable information to further the scientific understanding of Wildland-Urban Interface (WUI) fires. Most post-incident studies involve data collection in the field (i.e. a "research field deployment"). In this review, technical reports of post-incident studies for WUI fire and other natural disasters were analyzed and professionals directly involved in WUI fire research field deployments were interviewed. The goal of this review is to provide a resource for future WUI studies regarding the development of safe and effective fieldwork procedures, the collection and integration of accurate and relevant data, and the establishment of practical lessons learned. Three main stages of WUI fire post-incident studies are identified and described in detail. Data collection methodologies, data attributes, logistical practices and lessons-learned were compiled from various past studies and are presented here in the context of application to WUI fire

New approaches to evacuation modelling for fire safety engineering applications

This paper presents the findings of the workshop “New approaches to evacuation modelling”, which took place on the 11th of June 2017 in Lund (Sweden) within the Symposium of the International Association for Fire Safety Science (IAFSS). The workshop gathered international experts in the field of fire evacuation modelling from 19 different countries and was designed to build a dialogue between the fire evacuation modelling world and experts in areas outside of fire safety engineering. The contribution to fire evacuation modelling of five topics within research disciplines outside fire safety engineering (FSE) have been discussed during the workshop, namely 1) Psychology/Human Factors, 2) Sociology, 3) Applied Mathematics, 4) Transportation, 5) Dynamic Simulation and Biomechanics. The benefits of exchanging information between these two groups are highlighted here in light of the topic areas discussed and the feedback received by the evacuation modelling community during the workshop. This included the feasibility of development/application of modelling methods based on fields other than FSE as well as a discussion on their implementation strengths and limitations. Each subject area is here briefly presented and its links to fire evacuation modelling are discussed. The feedback received during the workshop is discussed through a set of insights which might be useful for the future developments of evacuation models for fire safety engineering

Roxborough park community wildfire evacuation drill: data collection and model benchmarking

Wildfires are increasing in scale, frequency and longevity, and are affecting new locations as environmental conditions change. This paper presents a dataset collected during a community evacuation drill performed in Roxborough Park, Colorado (USA) in 2019. This is a wildland-urban interface community including approximately 900 homes. Data concerning several aspects of community response were collected through observations and surveys: initial population location, pre-evacuation times, route use, and arrival times at the evacuation assembly point. Data were used as inputs to benchmark two evacuation models that adopt different modelling approaches. The WUI-NITY platform and the Evacuation Management System model were applied across a range of scenarios where assumptions regarding pre-evacuation delays and the routes used were varied according to original data collection methods (and interpretation of the data generated). Results are mostly driven by the assumptions adopted for pre-evacuation time inputs. This is expected in communities with a low number of vehicles present on the road and relatively limited traffic congestion. The analysis enabled the sensitivity of the modelling approaches to different datasets to be explored, given the different modelling approaches adopted. The performance of the models were sensitive to the data employed (derived from either observations or self-reporting) and the evacuation phases addressed in them. This indicates the importance of monitoring the impact of including data in a model rather than simply on the data itself, as data affects models in different ways given the modelling methods employed. The dataset is released in open access and is deemed to be useful for future wildfire evacuation modelling calibration and validation efforts.This study was supported by National Institute of Standards and Technology, U.S. Department of Commerce under award 60NANB18D255. The EMS was developed by the University of Cantabria within the ASSISTANCE project funded by the European Union’s H2020 research and innovation programme under grant agreement No. 832576

Burning down the silos: integrating new perspectives from the social sciences into human behavior in fire research

The traditional social science disciplines can provide many benefits to the field of human behavior in fire (HBiF). First, the social sciences delve further into insights only marginally examined by HBiF researchers, in turn, expanding the depth of HBiF research. In this paper, I present examples of studies from the fields of social psychology and sociology that would expand HBiF research into non-engineering or ‘unobservable’ aspects of behavior during a fire event. Second, the social sciences can provide insight into new areas of research; in turn, expanding the scope of HBiF research. In this section, I introduce pre and post-fire studies and explore potential research questions that fall outside of the response period of a fire, the phase upon which, most focus is currently placed. Third, the social sciences elucidate the value of research methods available to study human behavior. Qualitative research methods are specifically highlighted. These three benefits will allow HBiF researchers to collect a wider range of data, further develop and expand current behavioral knowledge, and increase the impact of this research for both social and engineering applications. Finally, I end with a discussion on possible ways to better integrate the social sciences within human behavior in fire

Terror defeated: Occupant sensemaking, decision-making and protective action in the 2001 World Trade Center disaster

This dissertation is a qualitative study of occupant behavior in response to the 2001 World Trade Center (WTC) disaster. Through analyses of transcripts from 245 face-to-face interviews with survivors from both WTC towers, collected by Project HEED, I investigate the pre-evacuation period in what became the largest full-scale building evacuation in history. The objectives of this study are to understand the types of actions performed before occupants began evacuation via stairs and elevators and why those actions were taken to improve techniques used and to address inadequacies in evacuation modeling tools. Drawing on social psychological theories of human action in normal times, collective behavior and sensemaking during normative crises, and emergency decision-making and protective action in response to hazards and disasters, and research on decision-making under uncertainty (including the importance of satisficing rationality), I examine how interviewees made sense of environmental cues, interpreted the situation and danger to themselves and others, and decided upon pre-evacuation actions, either to seek confirmation or achieve protection. Subsequently, I developed a predictive conceptual model of pre-evacuation actions by identifying the linkages between occupant- and situationally-based factors and the actions performed. I argue that occupant pre-evacuation behavior in the WTC disaster can be conceptually modeled by understanding both the disaster environment and the meanings individuals assigned to that environment. On 9/11, occupants consistently developed new social norms and lines of action based upon the meanings that occupants assigned to the situation, including perceptions of risk, familiarity with the building and others in the building, and responsibility for others. These meanings were dependent upon the receipt of environmental cues as well as on pre-existing norms, experiences, training, and social roles. My thesis contributes to empirical studies of decision-making during disasters and building fires, emergency planning and management, and the field of computer evacuation modeling by examining the emergency decision-making process and the factors that influenced each stage of this process during the most deadly terrorist attack in U.S. history

Emergency notification: Warnings and alerts

Emergency communication is the provision of information to members of the public under imminent threat. This information can be disseminated to the public in two forms: alerts and warnings (Mileti and Sorensen 1990). The main purpose of an alert is to capture the attention of the public in preparation for a subsequent warning message. Warnings are then used to provide information about the emergency, such as emergency type, when it will manifest, and the forms of protective action that should be taken (e.g., evacuation or shelter-in-place)

Representing evacuation behavior in engineering terms

In performance-based analyses, engineers evaluate whether a building design and/or evacuation procedure allows occupants sufficient time to evacuate before fire conditions become untenable. Guidance exists for the calculation of the time until conditions become untenable in areas of the structure (known as the available safe egress time) during fire situations. This article presents a method for determining the amount of time required for building occupants to reach a defined point of safety (known as the required safe egress time) for a particular building design or scenario. The method requires the engineer to identify real-world factors from the building conditions/situations that influence human performance (e.g. evacuation), understand the nature of their impact on human performance and then represent this impact in terms that can be employed within evacuation model calculations. An example is also presented to demonstrate the method described here