NIST GCR 15-1000

Risk-Informed Performance-Based
 

Design Concepts and Framework
 

Brian J. Meacham 

Alberto Alvarez-Rodriguez 

Worcester Polytechnic Institute 

This publication is available free of charge from: 

http://dx.doi.org/10.6028/NIST.GCR.15-1000
 

 

 

 

NIST GCR 15-1000
 

Risk-Informed Performance-Based
 

Design Concepts and Framework
 

Prepared for 

U.S. Department of Commerce 

Engineering Laboratory 

National Institute of Standards and Technology 

Gaithersburg, MD 20899-8660 

By 

Brian J. Meacham 

Alberto Alvarez-Rodriguez 

Worcester Polytechnic Institute 

This publication is available free of charge from: 

http://dx.doi.org/10.6028/NIST.GCR.15-1000

March 2015 

U.S. Department of Commerce 

Penny Pritzker, Secretary 

National Institute of Standards and Technology 

Willie May, Under Secretary of Commerce for Standards and Technology and Director 
 

 

Risk-Informed Performance-Based Design for Fire:
 

Concepts and Framework
 

Final Report – NIST Award 60NANB10D228 

Prepared by 

Brian J. Meacham, Ph.D., P.E., FSFPE 

Alberto Alvarez-Rodriguez, Ph.D. 

Date 

June 2014 

Department of Fire Protection Engineering
 

Worcester Polytechnic Institute
 

100 Institute Road
 

Worcester, MA 01609 USA
 

http://www.wpi.edu/academics/fpe.html
 
 

 

 

 

 

 

 

Risk-Informed Performance-Based Design 

Abstract 

A new framework for a risk-informed performance-based approach to fire safety analysis and design has 

been proposed. It is structured around a paradigm in which the performance analysis is conducted relative 

to the performance of a building-occupant system within a broader context of the managing risk of an 

acute event (e.g., fire) on the chronic state of the system. The role of risk characterization, targets and 

vulnerabilities, direct and in-direct impacts, and approaches for assessing and mitigating the likelihood of 

disruptive events on the desired performance of the building-occupant system are addressed. In addition, a 

test-bed environment, embodied within a web-based platform, has been proposed to facilitate a common 

location for data and information in support of risk-informed performance-based design. A key benefit 

will be the ability for practitioners, students and others to interactively use building geometries, data and 

analysis tools to gain and share experiences in the application of the new process. To support the test-bed 

environment, data have been collected and made available on heat release rate curves and associated 

information as part of a database on design fire curves, and a selection of building geometries for use fire 

effects, evacuation and other modeling and analysis have been compiled. 

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Risk-Informed Performance-Based Design 

Acknowledgements 

I would like to gratefully acknowledge the financial support provided by the National Institute of 

Standards and Technology (NIST) under award 60NANB10D228 which facilitated the research and 

outcomes as described herein. This award was used to support a large number of graduate students in the 

Department of Fire Protection Engineering who contributed to this effort. 

I would like to especially acknowledge the significant effort and contributions from my co-author, Dr. 

Alberto Alvarez-Rodriguez, who through the course of his Ph.D. and post-doctoral studies developed the 

fundamental frameworks and components as described in this report and associated annexes. Dr. AlvarezRodriguez’s work ultimately has provided a structure that can be used as a foundation for the next 

generation of risk-informed performance-based design for fire. I would also like to gratefully 

acknowledge other WPI graduate students who provided research in support of this effort: Manuel 

Hurtado, William Ivans, Jin-Kyung Kim, Matthew Ferreira, Arthur Gager, Kamal Aljazireh and Shane 

Cherney. 

I would also like to acknowledge the contributions of Dr. Cornelius Albrecht, who illustrated during his 

post-doctoral research at WPI, how a reliability-based approach to risk-informed performance-based 

design which he developed during his Ph.D. studies fits into the overall framework and path forward for 

the future. 

Finally, I would like to gratefully acknowledge the feedback and support of the NIST Technical Officer 

for this grant, Mr. Richard Peacock, for his guidance, feedback and facilitation of information interchange 

amongst the research team and researchers at NIST and elsewhere over the course of the project. 

Brian J. Meacham 

Project Principal Investigator 

Disclaimer 

All research, summaries, opinions, findings, conclusions and recommendations expressed in this report 

are those of the authors and do not necessarily reflect those of the National Institute of Standards and 

Technology or other sponsors, institutions, agencies or organizations which have supported this research. 

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Risk-Informed Performance-Based Design 

Contents 

Abstract.........................................................................................................................................................2
 

Acknowledgements.......................................................................................................................................3
 

Disclaimer.....................................................................................................................................................3
 

1 Introduction...........................................................................................................................................5
 

2 Report Structure ....................................................................................................................................9
 

3 Need for New Performance-Based Design Approach ........................................................................11
 

4 Need for a Paradigm Shift to Accommodate New Approach.............................................................13
 

4.1 Building-Occupant System .........................................................................................................14
 

4.2 Chronic and Acute Operation .....................................................................................................15
 

4.3 Disruptive Events........................................................................................................................16
 

4.4 Summary of Key Concepts.........................................................................................................16
 

5 Framework for Risk-Informed Performance-Based Fire Design........................................................18
 

6 Risk Characterization and Analysis Issues .........................................................................................24
 

7 Consequence Analysis Issues..............................................................................................................27
 

8 Data.....................................................................................................................................................29
 

8.1 Building Geometries ...................................................................................................................29
 

8.2 Design Fire Data .........................................................................................................................29
 

9 Vulcan Initiative..................................................................................................................................31
 

10 Outcomes, Ongoing Efforts and Recommended Future Research..................................................33
 

10.1 Outcomes ................................................................................................................................33
 

10.2 Ongoing Efforts ..........................................................................................................................33
 

10.3 Recommended Future Research..................................................................................................34
 

11 Summary and Conclusions..............................................................................................................35
 

References...................................................................................................................................................36
 

Annexes ......................................................................................................................................................39
 

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1 

Risk-Informed Performance-Based Design 

Introduction 

Performance-based building codes have been implemented in numerous countries world-wide. In 

addition, performance-based approaches to fire safety analysis and design are widely used, both in 

countries with performance-based building codes as well as those with prescriptive-based codes. 

However, most building codes – prescriptive- or performance-based – lack quantitative risk, safety or 

performance criteria, and decisions regarding acceptance criteria often rests with the fire protection 

engineer and design team, often with no benchmarking against other buildings. As a result, there is a high 

degree of variability in fire engineered building design solutions and in the review and approval of these 

solutions, and therefore in the levels of fire safety provided in buildings that have been designed using 

performance methods. There have been few fire-related failures that can be attributed to “unacceptable” 

fire safety performance being delivered under the current performance-based fire safety design 

framework. However, performance failures under prescriptive codes and in other regulated areas, 

perceived quality concerns, and a desire to be more transparent have motivated several countries to try 

and better understand and quantify the level of fire safety and performance being provided in deemed-tosatisfy solutions (acceptable solutions, approved documents) and to establish quantitative measures for 

use in next generation performance-based building codes and performance-based fire safety design 

approaches. 

In order to help address issues of risk and performance quantification, this effort began with the lofty 

goals of developing a methodology that could be used for identifying, quantifying and agreeing the level 

of building fire risk as reflected in building codes and in practice, and providing guidance for the 

development of quantified design fire loads and performance criteria which can be used in the next 

generation of performance-based building codes and fire safety design. The intent was to structure the 

methodology and guidance so as to achieve target levels of tolerable building fire safety and performance. 

While significant progress was made in each of these areas, no ‘magic bullet’ was found which addresses 

all of the concerns in any particular area. There are several reasons for this, many which are obvious and 

generally understood in practice, while others which are more subtle, having been revealed during the 

course of this work. First, the problem is highly complex – combining social and political aspects of risk 

perception and tolerability with technological approaches to risk and performance assessment – in a data 

poor environment where a broadly agrees and comprehensive taxonomy is lacking. Second, fire risk 

assessment tools and methods exist, but targets or levels of ‘tolerable’ risk and methods to characterize 

them are not broadly agreed across social, technical, economic and political arenas. This starts with 

simple concepts such as who or what is at risk, from what, and what level of safety or protection is 

appropriate. 

Similar challenges exist with respect to characterizing and defining performance expectations. While 

many engineering disciplines have defined ‘performance’ within their area, and assessment tools, 

methods and (some) data exist to support performance assessment, a common understanding across 

disciplines is lacking, and a structure for holistic performance characterization of a building is absent. 

This is particularly challenging with respect to development of a performance structure for regulation, 

which necessarily should consider all performance aspects in delivering a ‘well-performing’ building 

under the conditions expected and operation and use desired over the life of the building. This is not just 

an issue of different disciplines (e.g., structural versus fire), but manifests even when limited to a single 

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Risk-Informed Performance-Based Design 

discipline / performance area, such as fire. In the current paradigm, building fire performance related to 

life safety might be defined differently than building fire performance for property protection, which 

might be different from building fire performance for protection of mission. In the end, however, it is the 

performance of the building against fire – with respect to all performance objectives – which is important 

[1]. This can be illustrated by example. 

On March 17, 2000, lighting struck the industrial plant of Philips NV, located in Albuquerque, New 

Mexico, USA [2]. As a consequence a small fire started within the facility but was extinguished by 

sprinklers and staff in less than 10 minutes. There were no injuries and the fire fighters arrived at the plant 

just to record a minor blaze. Considered solely from a fire performance perspective, this event and 

response could be considered a success. For example, following current performance-based design 

guidance, the objective may have been to limit the spread of fire, criteria may have been established for 

controlling a fire to a certain size, a sprinkler system was determined to be appropriate for fire mitigation, 

and in the end, the sprinkler system operated as intended and limiting the fire. However, this 10-minute 

fire ultimately resulted in some US$2b in losses. How did this occur? It could be argued that the loss 

occurred as a result of focusing on code requirements, or even on a fire protection objective for the 

facility (e.g., limit fire size), and missing the impact of the facility fire performance on the company and 

those clients which this facility supplied. If the focus was on the broader performance of system in which 

the facility was only one part, things might have turned out very differently. 

In this case, the Philips plant was engaged in manufacturing of semiconductor chips for some 30 clients, 

including the mobile phones companies Nokia and Ericsson, whose orders accounted for 40 percent of the 

Albuquerque plant’s production. As one might expect, a semiconductor manufacturing facility such as 

this cannot tolerate any dirt or particulate in normal activities, in any of its clean rooms, much less soot in 

case of a fire. While the fire was small, therefore, the first order impacts could be anticipated to be high, 

particularly if soot or other products of combustion from the fire could affect the fabrication process or 

chip storage. This in fact occurred. However, that was not the sole contributor to the loss. Not only did the 

fire destroy the chip batches in the furnace (with an equivalent of thousands of mobile phone production) 

but also smoke, soot and the tramping of staff and fire fighters from the fire scene (in the mix of dirt and 

water) contaminated chips at every stage of the production, increasing that loss to millions of mobile 

phone chips. Unfortunately, the losses for Philips did not stop at the ones related to property damage. 

Phillips estimated that removing the dirt from the clean rooms would result in one week of down time. 

However, after two weeks, Philips staff realized that the disruption caused by the fire would take several 

weeks before production could restart. This had a significant impact relative to the responses to the fire 

from the facility’s main clients, Nokia and Ericsson. 

When Nokia and Ericsson were informed about the fire and Philip’s initial estimate of downtime, they 

each dealt with the situation differently. The Nokia response was to work closely with Philips and other 

chip providers so to maintain its own production of mobile phones and satisfy its customers in a period of 

time when demand for this type of product was booming worldwide. Ericsson’s reaction was different: 

they treated the fire incident at the Philips plant as a ‘technical matter’ which would result as a chip 

production disruption of one week only (Philip’s original estimate), which is something that could easily 

be taken care of. Unfortunately for Ericsson, the disruption lasted longer and by the time it realized the 

size of the disruption, it was too late and Ericsson failed to deliver mobile phones to its customers. 

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Risk-Informed Performance-Based Design 

Having failed to deliver its new generation of mobile phones, Ericsson reported losses between US$430 

and US$570 million in the first disruption-affected quarter. In addition to the fire disruption effects, 

incorrect product mix and marketing problems which followed contributed to what ultimately became a 

US$2.34 billion loss for Ericsson’s mobile phone division by the end of 2000. Results from this included 

loss of market share to Nokia, and to a merger of Ericsson with Sony for them to continue in the areas of 

design, production and marketing mobile of phones. By contrast, Philips's chip sale loss, estimated to a 

US$40 million, was almost covered by a 39 million Euro settlement with its insurance company. 

While one can argue that Philips ended up ok, at least as compared to Ericsson, the point is that a focus on 

fire protection system performance, as opposed to the overall system performance (manufacturer, insurer 

and client), led to intolerable outcomes. Examples such as this made it clear that ‘performance’ had to be 

recast in a more holistic way, such that the focus is not specifically on the fire and how people and 

systems respond to the fire, but on the impact that a fire (or other event) might have on the safety and 

operational performance of the ‘system’ within which the building resides. Likewise, at a building level, 

the focus needs to be on the broader ‘building-occupant system’ performance, and not just the fire 

protection systems performance. This is critical because the overall risk and vulnerability profile and 

operational and safety performance expectations of a building are ultimately a function of the ‘buildingoccupant’ system and how that system might be disrupted by a fire or other event, and less about the 

‘event-mitigation’ approach commonly used today. 

In reviewing the Philips fire and others [3], it also became clear that in order to better characterize the risk 

posed by fire within a ‘building-occupant’ system, specifically how likely it might be to have an event 

(fire) that results in an intolerable outcome (consequence), there is benefit to decoupling the frequency 

(probability, likelihood) of event occurrence from the analysis of potential consequences and the 

likelihood that they will occur [4]. It is also necessary to introduce the concept of targets and vulnerability 

in the assessment for both direct and in-direct consequences. The role of fire safety management over the 

life of the building is an important part of the assessment as well. It was also found that evaluation of the 

fire protection measures, in isolation and independent of how the building will be used throughout its life, 

might lead to a ‘disconnect’ between these measures and the context of the building in use. In numerous 

instances, investigation reports of fire events reflected how the interaction between the building, fire and 

occupants influence each other during events, and how normal use of the building could have a negative 

impact on fire system performance. This led to the understanding that the system within which fire 

protection is being designed needs to be considered in two states: chronic, or normal operation, and acute, 

or operation at the time an event such as fire occurs [1,4]. The fire disruptive event itself needs to be 

considered between two chronic states of the system, because of the importance of the recovery phase 

after fire extinguishment. 

One sees this type of behavior happening over and over in the literature, often with respect to how people 

use buildings during a fire (acute state) in much the same manner as they have come to use the building 

during the normal (chronic) state (e.g., exiting the way they came in, failing to close doors behind them 

which might help control fire, ...). In a fire, evacuation becomes an acute response by building occupants 

for whom fire is a disruptive event, which occurs during the otherwise normal or chronic building use. 

Since means of egress are not completely independent from the other building components, such as rooms 

or other spaces delimited by doors, corridors, atria, both the chronic and acute environments need to be 

considered. If the chronic situation is to prop open the doors to facilitate normal use, for example, but 

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Risk-Informed Performance-Based Design 

there is an expectation that the doors will be closed during an acute condition (e.g., fire), then the 

expected building fire performance may not be achieved. This is a significant contributor to the risk 

assessment – reliability of expected system performance. 

Analysis of the situation with current approaches to performance-based design also highlighted issues 

associated with lack of data for frequency and consequence analysis, and with wide variation in the 

application of tools and data for each. On the frequency (probability, reliability) data side, current 

guidance often points engineers to such resources as National Fire Protection Association (NFPA) 

statistics on fires in buildings of different occupancies. However, the data are often aggregated, and the 

classification NFPA uses is different than the building uses identified in the International Building Code 

(IBC) [5], which can be in turn have variations when one goes from a general classification (such as 

Institutional) to a specific type of institution (e.g., ambulatory care), to a specific building (hospital) 

design. The net result is that readily available data might not provide all that much guidance for a specific 

building design, and that more specific data and guidance as to how to use the data may be needed [6]. 

The same is true for the consequence analysis component. There is a wide range of tools available for fire 

effects, evacuation, structural analysis and more. Within each component, there is wide variation in the 

tools, the data required for the tools to be used, the certainty in predictive capability, user concerns and 

more [7,8]. More specific guidance is helpful, and is indeed needed. In addition, however, data in a 

format which can be consistently applied would also be helpful, especially in key areas such as design fire 

data. If one could collect data into a readily accessible place and present it in a readily useable format, 

provide guidance on how to use the data appropriately in the analysis tool, and provide users a platform 

for learning and applying the data and tools to common building configurations, the overall uncertainty in 

the performance-based design process and confidence in application of tools and data would go up. This 

research explored these issues in some detail, proposing a web-based environment (test-beds) within 

which data could be found, applied using tools to a variety of building configurations, to address a broad 

range of building fire performance issues, within the risk-informed performance-based framework [1, 7­

9]. Of particular benefit to practicing engineers right away is the database of design fire curves and 

template for engineers and scientists to upload more for all to use [see Annex F and G]. In due course 

these and other data, tools and methods will be available via the Vulcan Initiative website, a portal 

established to facilitate information exchange, test-bed studies and more (http://www.vulcaninitiative.net/index.html, Beta version, last accessed 30 June 2014). 

Ultimately, the above components and more have been integrated into a new framework for a riskinformed performance-based fire design [1, 4] and integrated into the Vulcan Initiative platform. While 

much more work is needed, the foundation has been laid by the effort to describe the necessary 

components needed to fully realize the new approach. Of particular need, in addition to data, is the 

development of detailed guidance documents, focused on specific occupancy types. A structure for how 

the guidelines can be prepared, and the type and level of detail of information required, is outlined in [1]. 

It is hoped that the Vulcan Initiative platform can serve as a mechanism for facilitating development of 

these guidelines in the future. 

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2 

Risk-Informed Performance-Based Design 

Report Structure 

As reflected in the introduction, a significant amount of research and development has resulted from this 

project, including publication of a Ph.D. dissertation and numerous journal and conference papers, 

compilation of design fire data for use in consequence analysis, and Beta-version launch of a web portal 

for facilitating collection, use, and advancement of data, tools and methods for use in a risk-informed 

performance-based environment. Given the availability of the publications in particular, this report has 

been structured to provide a brief overview of each research focus area and outcomes, with reference to 

the publication in which details can be found. In addition, where permitted, the publications are reprinted 

as annexes to this report. Several of the annexes have been provided as unique files as they are awaiting 

NIST CGR numbers. 

The major sections of the report are as follows: 

Section 3 – Need for New Performance-Based Design Approach: this portion of the report and associated 

reference papers discusses shortcomings in current codes, guidelines and practice, and where efforts 

should be focused to address these in next generation guidelines. 

Section 4 – Need for Paradigm Shift to Accommodate New Approach: this portion of the report and 

associated reference papers discusses why a new way of thinking is needed in terms of considering the 

whole of building performance, and the role of the building and targets, as part of an integrated system. 

Section 5 – Framework for Risk-Informed Performance-Based Design: this portion of the report and 

associated reference papers outlines the new framework, highlighting the major components. 

Section 6 – Risk Characterization and Analysis Issues: this portion of the report and associated reference 

papers looks to the future in terms of thoughts for how risk characterization can be better accomplished, 

providing a potential approach. 

Section 7 – Consequence Analysis Issues: this portion of the report and associated reference papers 

discusses issues with selecting the right tool for the job, addressing uncertainty and variability, and 

reminding engineers of the need to consider the dynamic integration of fire-people-building interaction as 

part of consequence assessment. 

Section 8 – Data: this portion of the report overviews data collected as part of this effort, including data 

on HRR curves for use in modeling provided in associated spreadsheets. 

Section 9 – Vulcan Initiative Website: this portion of the report and associated reference papers 

overviews the current Beta version of the website and the plans for future enhancement. 

Section 10 – Outcomes, Ongoing Efforts and Recommended Future Research 

Section 11 – Summary and Conclusions 

Annex A – Alvarez Ph.D. Dissertation (NIST GCR pending) 

Annex B – High-Level Comparison of IFEG, SFPE PBD Guide, BS 7974, and ISO 13387 (NIST GCR 

pending) 

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Annex C – Alvarez unpublished manuscript for Building Research & Information which discusses the 

paradigm shift and associated components. 

Annex D – Albrecht life safety risk assessment of room-corridor arrangement 

Annex E – Albrecht life safety risk assessment of atrium arrangement 

Annex F – Guidelines for using “HRR Catalog” 

Annex G – Interflam 2013 paper on Vulcan Initiative 

Annex H – Structure and pages of Beta version of the Vulcan Initiative website 

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3 

Risk-Informed Performance-Based Design 

Need for New Performance-Based Design Approach 

To understand the context for why change is needed, a review was undertaken of worldwide experience 

using standards, codes and guidelines related to performance-based fire protection design for buildings 

over the past twenty or so years [1, 3], building upon prior research of a similar nature [10-12] in order to 

obtain an up-to-date understanding of the situation. This benchmarking exercise identified examples of 

shortcomings in the interpretation, application and implementation of the performance-based design 

process, apparent inconsistency in the resulting levels of performance achieved and several opportunities 

to enhance the process, as summarized below [1, 3, 4]. 

•	 The application of generic guidance, as embodied in current performance-based design and fire safety 

engineering guidelines, to specific projects may result in important fire performance concerns being 

missed, especially but not exclusively by inexperienced engineers. Advising someone to ‘develop fire 

scenarios’ and ‘consider occupant characteristics’ is a good starting point, but does little to help 

identify how to actually construct a fire scenario, or what occupant characteristics to consider, or how 

occupant characteristics might change by building use or by country where it is located, etc. This 

need is also highlighted in [6], presented as Annex A. 

•	 There are numerous shortcomings with the definition, use and quantification of performance / design / 

acceptance criteria by the fire protection engineer (FPE) on a one-off, project-specific basis, as 

opposed to applying them to all facilities of like type and characteristics. The first issue is that these 

criteria should be determined by policy makers, since they reflect minimum risk, safety and 

performance targets for public safety. This should not be an individual fire protection engineer 

decision. This is not to say that the fire protection engineering community cannot suggest criteria 

based on scientific and engineering knowledge, data and tools of evaluation, but that the policy 

makers should decide which criteria to implement and to achieve what targets. 

•	 In current practice, the selection of design fire scenarios is focused on the evaluation of fire protection 

systems performance, often in isolation, rather than to test the holistic building fire safety 

performance and the performance of the building as part of a larger system. As discussed with the 

Philips example in the Introduction, failure to consider what ultimately determines acceptable or 

tolerable performance can result in fire protection designs which are ineffective when needed. 

•	 Given the lack of data for undertaking quantitative risk assessments with a high degree of confidence, 

many engineers conduct comparative analysis between the levels of expected performance resulting 

from an engineered solution with the levels of expected performance based on prescriptive 

requirements that are devoted to protect building occupants. However, as reported in the literature 

these are often undertaken without an appropriate or comprehensive basis of comparison, especially 

considering that the prescriptive provisions most likely did not consider any specific fire scenarios or 

quantitative performance targets. There are risk-informed approaches, however, which can be 

effective comparative analyses (see Annex D). 

•	 Current fire engineering guidelines contain insufficient guidance to determine the most influential 

factors affecting the efficacy of proposed fire protection design solutions. In part this comes from the 

lack of guidance identified above, but also the lack of requiring identification and treatment of 

uncertainty, and demonstration of robustness of the design through sensitivity analysis and other tests. 

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•	 There is significant shortcoming in current practice associated with assuming ‘idealized’ performance 

of fire protection measures (i.e., they will always work and they will always be in the same condition 

as at the time of design, omitting deficiencies resulting from age, users, etc.) as compared with ‘real 

life’ performance of installed measures. In reality, the efficacy of fire protection systems can be 

lowered by human action (e.g., blocking sprinkler heads, closing valves, blocking doors open, 

increasing fuel load) and general component aging and reliability issues. While current practice might 

require certain testing, inspection and maintenance be undertaken, there is widespread evidence of inuse systems not being in appropriate condition to perform as expected at the design stage. 

•	 There is generally too specific of a focus on consequence analysis of design fire scenarios around 

narrow aspects of building component or fire safety system performance, without having the entirety 

of the required or desired performance picture adequately defined. This again touches on the Philips 

type problem: the sprinkler system worked as designed, but the overall performance of the fire safety 

system (which should have included post-fire procedures) failed. 

•	 There appears to be significant use of ‘literature values’ (i.e., input parameter values found in the 

literature) in analysis and modeling without demonstration that the values are appropriate to the 

specific problem at hand, or that the values are the appropriate ones to use (as selected from multiple 

options). 

In a related effort, evaluation of a set of existing, English-language guides and standards on performancebased design for fire and fire safety engineering was undertaken to identify commonalities and areas of 

significant difference (see [13], included as Annex B). As with the review by Alvarez, it was found that 

while common structure exists, and some guides / standards go into more detail than others, as Alvarez 

also found the guidance is generic with respect to how one specifically identifies occupant and building 

characteristics of concern, fire scenarios of concern, design basis fires that are appropriate, and suitable 

criteria to apply, as well as the extent to which uncertainty and sensitivity should be addressed in the 

evaluation of proposed mitigation options. 

In order to overcome the challenges identified during these reviews, it is suggested that the solution is to: 

(1) re-center the performance-based fire protection design process on the subject of its application, that is 

to say the system formed by the building and its occupants, as opposed to fire protection systems 

assessment; (2) create a risk-informed performance-based fire protection design process wherein the level 

of detail in guidance documents is increased and focused on specific occupancies and characteristics; and 

(3) provide a mechanism to help fire protection engineers select the most appropriate tools and data for 

the types of applications they are considering. How this can be achieved is addressed in subsequent 

sections. 

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4 

Risk-Informed Performance-Based Design 

Need for a Paradigm Shift to Accommodate New Approach 

While a wide range of definitions and criteria exist in the literature, it is suggested that main drivers for 

application of performance-based design (PBD) include demands from stakeholders for better building 

performance in use across a wide range of stakeholder expectations, in conjunction with a change in 

legislation allow a broader use of engineered options instead of simply fulfilling prescriptive 

requirements. Within a PBD framework, the demand of the ‘end users’ of the building (i.e. building 

occupants) become priorities so that PBD provides a more ‘client’ oriented process than the one used 

when following building code regulations. Conceptually, a PBD approach can be applied to all the 

components of a building project, including among others, acoustics, aesthetics, operability, 

sustainability, and safety. It involves numerous actors, including on one hand the building users who 

should define the level of performance of the building, and on the other hand, the building industry which 

should create optimal solutions in order to achieve this level of performance within a regulatory 

framework established by policy makers. 

However, because of the complexity of the engineering thinking related to these building components, 

PBD guidance has been (a) segmented such that each engineering discipline has to consider separately 

how clients' objectives connected with each of the building components should be achieved, and (b) 

‘genericized’ to accommodate multiple solutions. This applies not only to design of building components 

dedicated to the normal use of the building (e.g., mechanical components including heating, ventilation, 

and air conditioning (HVAC) and plumbing) but also to building components installed to address 

disruptive events, such as fires, earthquakes, or any type of emergencies susceptible to affect the safety of 

building occupants or damage the building contents and structure. As such, while PBD guidance has thus 

far been elaborated to treat discipline-specific ‘normal’ building performance (e.g., energy, HVAC) and 

specific safety objectives (e.g. fire and earthquakes) those conducting analyses must have specialized 

expertise, and there is little integration across or between disciplines. In practice, however, the building 

end users are not really interested in the performance of individual building components and systems, but 

rather, the performance of the building as a whole. To achieve this, the design team is expected to address 

the multitude of building components and systems and have them co-operate in order to achieve this 

seamless daily performance for both normal use and during and after disruptive events. This does not 

always occur as well as would be hoped. 

Therefore, given the shortcomings in the existing approaches relative to needs of uses, a new paradigm 

for building performance was developed around the concept of ‘building-occupant’ systems, for which a 

new risk-informed, performance-based analysis and design approach was structured based on how 

‘disruptive events’ perturb the system. In brief, the idea is that instead of focusing on the performance of a 

particular technical system to function as intended (e.g., defining acceptable performance of a sprinkler 

system as activating at a certain fire size), the performance assessment should be conducted in the context 

of how the technical system helps to achieve the user-defined performance of the building during and 

after the event (e.g., fire). For PBD for fire, this means moving away from performance defined in terms 

of performance of mitigation systems in isolation, to fire performance of the building-occupant system in 

achieving more global life safety, building performance, operational performance or related objectives. A 

summary of key elements of the new paradigm are provided below and detailed in Annex A [1] and C 

[14] and overviewed in [4]. 

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4.1 Building-Occupant System 

In many countries, buildings are classified in terms of the general class of use, such as places of assembly, 

business occupancies, residential, and so forth. However, these general descriptions lack the complexity 

to describe the interaction of the building users in the context of the building. To address this, it is 

recommended to identify more appropriate ‘building-occupant’ systems. An obvious way to categorize 

the different existing ‘building-occupant’ systems is to follow the classification established in building 

regulations. However, as pointed out in the Introduction and detailed in [1, 14], there is significant 

inconsistency in classification systems, and insufficient detail to adequately characterize building hazards 

and occupant risks. After reviewing several taxonomies and classification systems, a definition was 

developed: a ‘building-occupant system’ is a system defined by a structure (i.e., building) inside which 

occupants are engaged in a primary activity which can be quantified (e.g. activity number carried out by 

day or week) such that the performance of the system can be estimated by the level of the activity. In this 

paradigm, occupants are defined as persons who are physically inside the system, independently of the 

duration of their stay, and building components are defined as physical portions of the system, which can 

include spaces dedicated to a particular occupant activity (e.g., room for sleeping) of the system or in 

support of that activity (e.g. HVAC system). 

If one looks at a hospital, for example, there are different building areas which can be identified according 

to the functions they provide, such as reception areas, emergency rooms, examination rooms, operating 

rooms, patient rooms and intensive care units. Any area which can be grouped by function is defined as a 

‘functional’ zone, as they are created to fulfill the functions related to the daily objectives of the facility. 

In addition, there are utility areas which provide support functions, such as power, heating, ventilation 

and air-conditioning (HVAC), throughout the facility. These utility areas are to be identified as ‘utility’ 

zones, either as individual spaces (i.e., mechanical rooms, electrical rooms, cafeteria...) or throughout the 

building (such as the HVAC system). When designating zones, care should be taken to define them based 

on the ‘building-occupant’ system characteristics of importance. It is also important to identify direct and 

indirect relationships between the different areas of a system. 

For example, Figure 1 illustrates the required level of detail for different functional zones of a hospital, 

describing the types of population in each of the zones. For instance, people located in the reception area 

are future in-patients, visitors and staff and almost all of them are mobile and conscious. This is important 

as they would require no or little assistance in case of a hazardous disruptive event such as a fire. Inpatients located in emergency rooms or in operating rooms are undergoing surgery and are connected to 

life-supporting machines. This is important as extracting them during a fire would require following 

procedures and requiring time that may not be compatible with a rapidly growing fire. In addition, while a 

utility zone supporting a reception area may be important to facilitate the comfort of the occupants, a 

utility zone supporting an operating room functional zone is essential. If a fire occurs in the utility zone 

supporting a reception area the impact in the reception area could be limited to an ‘inconvenient’ loss of 

power or lighting. If a fire occurs in the utility zone supporting the operating room, the impact could be 

life-threatening. 

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Hospital 

Reception 

Examination 

Emergency rooms 

Operating rooms 

Intensive care 

Patient rooms 

Staff + in-patients (mostly mobile) + 

Staff + in-patients (not mobile and 

Staff + in-patients (not mobile) 

Staff + in-patients (not mobile) 

In-patients (not mobile) 

In-patients (not mobile and mobile) + 

Figure 1. People description according different functional zones of a hospital 

To summarize, characteristics of occupants within specific locations of a building, as well as the intended 

function of spaces in a building and contents in those spaces which are essential to achieving the required 

function need to be clearly understood, identified and categorized. This constitutes essential information 

required by the fire protection engineer (FPE) in order to address stakeholder objectives for ‘buildingoccupant system’ when elaborating a fire safety strategy. However, no current performance-based design 

process directs one to examine a building at such a level of detail, explains the reasons why such a level 

of detail is important, or provides guidance how to approach the assessment. In large part this is because 

current processes are focused too much on the fire event itself instead of being target-oriented, focusing 

on the objectives of concern within the specified functional zones or a well-defined ‘building-occupant’ 

system. 

4.2 Chronic and Acute Operation 

One can view buildings as having two states: chronic, or normal operation, and acute, which reflects some 

perturbation to the system (e.g., fire, power outage...). As long as things are generally fine in the chronic 

state, no thought is given to actions required during acute states. As noted above, this logic carries over to 

the performance of individual systems in a building. Generally speaking, building end users (e.g., owners, 

managers, occupants...) are not really interested in the performance of individual building components 

and systems, but rather, the performance of the building as a whole in maintaining acceptable conditions 

and operations in the chronic state.1 If the users can function well in the building, everything is fine. 

However, this can result in complacency with respect to maintaining systems which are infrequently used. 

This is especially true of systems which are only in place for emergencies, such as fire protection systems. 

As has been shown by reviewing the literature [1, 3], if the chronic state of the building is not considered 

during the design phase, assumptions about the efficacy of systems installed for use during acute states 

may be inappropriate (e.g., if it is assumed that fire doors will provide separation, yet it can be expected 

1 Building users clearly have some concern with systems which impact daily use (chronic operations), such as 

lighting, HVAC, elevators, etc. However, owners and managers are focused more on the fact that the building works 

to support their operations, without significant concern for small disruptions in individual support systems. 

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that occupants will prop open the doors, the expected performance of the fire doors during an actual 

emergency may not be achieved. As such, as part of the paradigm shift, it is deemed imperative to 

consider how the building-occupant system is expected to operate in its chronic state, and from that assess 

the efficacy of mitigation measures during acute states (fire, other). 

4.3 Disruptive Events 

Primary stakeholders in a building project, including the building owner and the potential users, generally 

define building performance objectives in terms of the everyday uses of the building (chronic state). In a 

hospital, for example, this performance is related to the type of treatments offered, the number of patients 

who can be treated, the types of equipment and services needed to treat patients, and so forth. For a 

school, performance is related to delivering education to the target student population, the number of 

registered students, the numbers and qualification of teachers or faculty required to deliver education, etc. 

For a museum, it is related to the exhibits and holdings, number of exhibition attendees who can be 

accommodated, security of the holdings, etc. Unfortunately, the owners and operators of these buildings 

do not always think about events which can disrupt this daily use (acute states). This has an impact not 

only during use, but with respect to decisions made at the design stage. Disruptive events can be of 

different natures [2], such as: supplier business disruption leading to operational vulnerabilities; fires, 

earthquakes, severe weather, accidents or terrorism leading to hazard vulnerabilities; currency exchange 

fluctuations leading to financial vulnerabilities; or new foreign competitors leading to strategic 

vulnerabilities. Such disruptive events can significantly impact the operation of a building and the mission 

it supports. If the building owner and other key actors are unprepared, the disruptive event can have 

catastrophic effects on continued operations [15]. Thus, in the new paradigm, fire should be viewed as a 

disruptive event which causes a transition in the building-occupant system from a chronic state to an acute 

state, and assessment of the overall system performance should be made with consideration of both 

conditions, up to the establishment of a new chronic state. 

4.4 Summary of Key Concepts 

In summary, there are several key concepts in the ‘building-occupant system’ paradigm which need to be 

incorporated into the next generation risk-informed performance-based approach: 

•	 Functional zones: spaces which are directly linked to the performance of the system (e.g. in 

hospitals, visiting areas where patients are checked in, patient rooms where patients are being 

prepared for surgery, operating rooms, intensive care units and patient rooms where patients recover 

before checking out); 

•	 Utility zones: spaces which indirectly contribute to the performance of the system, often providing 

support to the "functional zones" (e.g. storage rooms, electrical rooms, mechanical rooms); 

•	 Targets: key elements whose performance is of concern within systems (the actors or users of the 

functional zones). For example, targets can be building occupants (patients including their visiting 

families and friends and staff in hospitals, pupils and teachers in schools) or building contents 

(important piece of equipment required to contribute to the performance of the system such as a 

newly developed micro-chip in high tech industry or a priceless artifact in a museum); 

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•	 Disruptive events: every possible event (technological events, natural events, socio-economical 

events) having an effect on the performance of the system. A disruptive event lasts between two 

chronic states of the system. 

•	 Chronic states of the system: which represent the situations of the system while it is operating as 

designed or after each modification of its design (e.g. normal use of the system). 

•	 Chronic objectives: objectives the system is designed or subsequently modified, to attain during its 

chronic states; 

•	 Acute objectives: objectives the system is designed or subsequently modified, to attain during 

disruptive events; 

•	 Event effects: damaging effects of a disruptive event on a target. These can be ‘direct effects’ or 

‘indirect effect.’ With respect to fire as a disruptive event, ‘direct effects’ reflect fire-induced 

damage upon targets, such as heat, toxic, corrosive, irritant effects. ‘Indirect effects’ reflect loss of 

building components which are vital for the targets to perform in the system. For example, a fire can 

through ‘direct fire effects’ such as heat directly damage power cables to a life supporting 

equipment, which then has an indirect effect on the safety of people connected to this equipment. 

Going forward, these concepts have a significant impact on how a risk-informed performance-based fire 

protection design should be structured. To understand and characterize the risk, one needs to understand 

the building-occupant system, how the users expect the system to work in its chronic state, and how a 

disruptive event can affect the overall system during acute states. Analysis cannot be ‘genericized’ to 

broad groups, such as ‘occupants’, but should be focused on targets (which may be occupants) in the 

context of the functional and utility zones of a building, as the criteria for acceptable performance may 

vary by location for the targets (e.g., a patient in an ICU will have different tolerances to fire effects than 

a nurse working in the same ICU). Analysis of the risk must then be considered for disruptive events 

which impact the chronic states of performance in each functional and utility zone in terms of both direct 

and in-direct impacts. This holds true for quantification of likelihood of disruptive event and estimation of 

the consequences. Risk and consequence analysis should consider the likely response of systems required 

only during acute states, and the likely response of occupants given their propensity to think in terms of 

chronic operations. Reliability and efficacy of the systems designs should be assessed in this context as 

well. 

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5 

Risk-Informed Performance-Based Design 

Framework for Risk-Informed Performance-Based Fire Design 

Given the challenges with existing performance-based fire protection design approaches, and the benefits 

to be gained from a paradigm shift which revolves around assessment of overall performance of a 

‘building-occupant’ system during chronic states and as disrupted by unwanted events (acute states), 

considering target vulnerabilities across functional and utility zones, a new framework for risk-informed 

performance-based analysis and design was developed [1, 4, 13]. While developed with an eye toward 

fire as the disruptive event, the framework is robust enough to be used with any disruptive event (e.g., 

natural hazard, power outage), as the focus is on response of the system to perturbations rather than 

performance of individual system components with respect to their operation. 

First, the new framework separates the political aspect from the technical one, concentrating the political 

aspect at the very start and the very end of the analysis and design process, leaving only the technical 

aspects to the fire protection engineer (FPE). In the context of this framework, the political process 

includes regulated issues as well as stakeholder decisions. The principle of this separation is illustrated in 

Figure 2. At the start of the process, the stakeholders define the project and present all of the 

characteristics of the ‘building-occupant’ system to be examined: building parameters, occupant 

parameters and functional/support zones used during ‘chronic states’ of the system. The stakeholders still 

have to agree on the main ‘chronic’ goals and objectives related to the considered ‘building-occupant’ 

system and indicate if specific building attributes are of concern (e.g., atrium, high rise configuration). 

These are considered political aspects of the problem, as decisions are required by others than the FPE 

alone. Once decided, all of this information is transmitted to the FPE who starts the technical aspect of the 

process by selecting fire risk acceptance metrics that corresponds to the considered project. 

Political 

Stakeholders’ 

decision 

Political 

Stakeholders’ 

project 

definition 

Technical steps of the new PBFPD process 

Target 

vulnerability 

criteria 

estimation 

Fire risk 

analysis 

(quantification 

of the impact) 

Cost-benefit 

analysis 

Risk 

characterization 

Fire risk 

analysis 

(quantification 

of the 

likelihood) 

Evaluation of 

the integration 

of the fire 

protection 

measures in 

the system 

Figure 2. Risk-Informed PB Design Process [1, 4] 

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The first technical step, risk characterization, is about translating the fire safety engineering problem from 

a stakeholders' perspective to a FPE perspective, where the FPE has must consider all the targets and 

define risk metrics relevant to the different targets of the studied system. During Step 1, fire risk curves or 

matrices are used to translate stakeholder risk and performance objectives into the process for assessing 

the performance of the system to withstand fire threats, according to how often and how damaging these 

threats are. This is schematically illustrated in Figure 3 [4]. Performance metric Frequency of the disruptive event 

Probability 

Gravity 

Class 1 Class 2 Class 3 Class 4 Class 5 

Level 5 

Level 4 

Level 3 

Level 2 

Level 1 

Current "chronic" state of the "building-occupant" system, as a baseline of the study of the disruptive event 

Time 

Damage metric 

transcription of this information in a way that is relevant to the stakeholders 

Figure 3. Risk Characterization [1, 4] 

The stakeholders can then assess whether the performance of the building-occupant system meets their 

objectives, and if not, how they would modify the risk or performance objectives accordingly. This is 

illustrated in Figure 4. In this example, for a ‘frequent’ disruptive event, the stakeholders allow the 

performance of the system to be less than the one defined in the risk characterization: in other terms, they 

allow more property loss or a longer recovery time, depending on the damage metric. For a ‘less frequent’ 

disruptive event, the stakeholders allow the performance of the system to decrease as the one defined in 

the risk characterization. For a ‘rare’ disruptive event, the stakeholders do not allow the performance of 

the system to be less than the one defined in the risk characterization. Based on their performance 

requirements, a new fire risk curve can be constructed and fire disruptive events will then be assessed by 

their locations, in terms of (probability and consequences), relative to this new fire risk curve. 

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Performance metric 

Time 

Minimum levels of performance agreed among the stakeholders 

for a frequent, less frequent and rare disruptive event 

New fire risk curve taken into consideration the 

stakeholders' overall performance criteria 

Damage metric 

Figure 4. Risk Criteria Adjustment [1, 4] 

In Step 2, the FPE gathers target vulnerability metrics according to the nature and characteristics of each 

target of concern (as provided by the stakeholders). The FPE must then quantify the vulnerability criteria 

for each target in case of the disruptive event (e.g. evaluating the mechanisms by which the disruptive 

event can have direct and indirect effects on each listed target while taking into consideration the 

capacity/incapacity of the target to absorb the damage from the disruptive event and still be 

functional/loses its functionality). These could be, for example, tenability criteria for occupants (which 

may vary by occupant characteristic or functional zone), thermal heat flux criteria for cabling or other 

critical equipment or utilities, whose loss might have an indirect effect on other targets as well (e.g., a 

patient on life support), and so forth. 

The FPE then needs to gather information and functional descriptions of the building-occupant system, 

identifying critical components such as functional zones, utility zones, location, characteristics and 

vulnerabilities of targets... With this information the FPE can then undertake fire risk analysis, which is 

purposely disaggregated in the framework as frequency analysis (Step 3) and consequence analysis (Step 

4). In Step 3 it is anticipated that the FPE will apply various fire hazard analysis (FHA) and fire risk 

analysis (FRA) tools, including failure mode and effects analysis (FMEA), fault tree analysis (FTA), 

event tree analysis (ETA), as appropriate. ETA can be used with zones containing targets to assess 

performance of mitigation measures, using most probable fire ignition locations from NFPA data or other 

statistics as initiation points of these trees. In conjunction, FTA can be used with ‘affected targets’ being 

the final/top point in order to capture the indirect threats to the considered targets. Overall, the aim of Step Frequency of the disruptive event

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3 is for the FPE to assess and address fire events and associated responses that are relevant to the 

performance of the system in a quantified manner (i.e., assessment of fire events that could affect the 

stakeholders’ targets and fire protection measures or safety barriers to prevent these events from 

occurring, with a frequency estimated on fire ignition frequencies and reliability of the considered fire 

protection measures). 

Step 4 involves evaluation of event impact on the system targets. This involves analyses familiar to the 

FPE, including assessment of fire development and spread, response of people, structures other targets to 

fire, time for occupants to reach a place of safety, and so forth. However, the consequences should not be 

restricted to narrow areas of focus, such as occupant evacuation, but should be conducted within the 

context of the larger building-occupant system (again, consider the Philips case: the analysis may have 

demonstrated that the sprinkler could control the fire within 10 minutes of initiation, but likely missed the 

$2B loss). Even when focused on a particular component (e.g., occupant safety), the issue of different 

target characteristics, different zones, and direct and in-direct impacts needed to be considered, as 

outlined in the hospital example above. 

A key aspect of consequence analysis is quantification of design fires for use in assessing the potential for 

possible mitigation measures (trial design options) to deliver expected performance for the scenarios 

identified. A critical component of this analysis is selection of the design fire curve. Presently, little 

guidance exists on specifically how to construct a design fire curve, or from what data one should select 

suitable curves, and how to address associated uncertainty. In addition, a significant issue from the 

regulatory side is variability in the fire curves selected and used from one project to another and one fire 

to another. More on design fire curves and data can be found in Section 8 of this report. 

When conducting consequence analysis, it is important to consider the dynamic conditions of fire 

development and target response in an integrated manner. Currently, for example, safety of building 

occupants is often estimated via the (RSET/ASET) concept. While this can be appropriate if applied 

correctly (that is, considering each occupant relative to the fire as the fire and evacuation progresses), the 

ASET/RSET concept is currently applied in too much of an independent manner: fire effects models are 

used to estimate the time to reach untenable conditions, while separately egress models are used to 

develop estimates the time required for the building occupants to reach a place of safety, and often there 

is no time-based integration of the separate models and the influences on each other. In addition, current 

guidelines do not contain enough guidance on how to treat uncertainty and variability: how changes in 

building, fuel or human factors affects fire growth, or how human factors impact time to reach a safe 

place, and overall how uncertainty impacts the results of the evaluation of fire scenario consequences. 

With respect to the dynamic nature of the problem, the proposed framework focuses FPEs on the 

building-occupant system, which requires integrated analysis to be conducted of the building-occupantfire interactions. In addition, the framework includes a forum for collaborative projects, called ‘test bed’ 

environments [7-9], developed to facilitate the determination of the most appropriate tools, data and 

methods for FPEs to apply in order to quantify fire impacts for specific ‘building-occupant’ systems and 

for specific issues such as occupant evacuation, property protection or building structural response. With 

respect to uncertainty and variability, there are ways that this can be treated in a risk-informed manner. 

These include use of probability distributions on input variables for fire effects and evacuation models, 

and considering the cumulative probability function that is produced, such as described by Notarianni 

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[16], Baker et al. [17], Lord et al. [18] and others. There are also reliability-based approaches which can 

be applied, such as described by Albrecht [19-21]. Examples of how Albrecht’s are applied, and how fit 

into the new risk-informed performance-based framework, are presented in Annex D and E [21]. 

Ultimately, when the frequency and consequence analyses are complete, the FPE can propose sets of fire 

protection measures in order to minimize the occurrence of the damaging fires and mitigate the impact of 

these fire events on the system performance (i.e. the consequences of the fires events affecting the system 

targets). The benefits of various mitigation options, in terms of decreases of fire frequencies and impacts, 

can be synthesized in a risk curve as illustrated in Figure 5, with no protection measures, and with one or 

two sets of protection measures. 

Frequency of thedisruptive event 



   

Damage metric 

Figure 5. Impact of Mitigation Options on Risk [1, 4] 

Step 5 of the new process is aimed to avoid critical situations where the fire protection measures installed 

in a ‘building-occupant’ system are ignored, or ‘rejected’ by this system, potentially leading to a 

catastrophe in case of a fire occurring. It does this by requiring the FPE to analyze how protection 

measures are used in the ‘chronic’ state of the building so as to try and prevent the measures from being 

counterproductive or ‘rejected’ by the system due to competing objectives or simple ignorance of the 

operation or benefit of the safety measure by building users. An example of a ‘rejected’ measure can be 

seen in the photograph in Figure 6, taken in a relatively new hotel (less than 10 years old). 

Figure 6. Hotel Stairway Lobby Vestibule [1, 4] 

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The photograph shows a vestibule with two fire rated doors, designed to protect the single stairwell within 

the 5-story hotel, from being invaded by smoke in case of a fire [4]. The ‘acute objective’ is that the 

closed doors will prevent smoke spread. However, the ‘chronic objective’ is to the ease of passage of 

guests with luggage between the hotel rooms and elevator lobby, which is shared with the stairwell. In 

this case, the ‘chronic objective’ is achieved by blocking the doors open, which negates the protection 

designed for the ‘acute’ event. 

Step 5 goes beyond the documentation of how the fire protection measures are designed, installed and 

maintained in the current PBD processes, which primarily focus on telling the building/owner manager 

what they should do to keep the protection systems operational, but do not take into account failure in the 

design process (e.g., see NFPA 101 Design Scenario 8), requiring the FPE to evaluate how the fire 

protection measures previously considered in the fire risk analysis would be integrated into the studied 

system, in other terms, if they are going to be compatible with the system components which are used on 

an everyday basis so they are not counter-productive and therefore ignored or worse rejected by the 

system. 

Step 6 of the technical process is for the FPE to perform a cost-benefit analysis of the fire protection 

measures established during the fire risk analysis. Cost-benefit analysis is only suggested in current PBD 

guidance. However, a clear aim of stakeholders is to cost-effectively mitigation fire risks in the context of 

overall system performance, so this needs to be a required step. Returning to the Philips example, the fire 

safety system that was in place ultimately contributed to a $2B loss: it is likely that had the expected 

value of the supply chain interruption was included in the overall assessment, it would have been possible 

to allocate more resource to preventing that situation. 

At the end of the new risk-informed performance-based design process, a political decision is taken by the 

stakeholders based upon a technical analysis by the FPE, including results from a fire risk analysis 

describing how often and deep fire events would degrade the overall performance of the system, a 

document showing how the selected fire protection measures would be integrated into the system and a 

corresponding cost-benefit analysis of these measures. 

While this framework might be unfamiliar to many FPEs, it actually mirrors quite well the risk-informed 

performance-based approaches which already exist in specific industries. In the nuclear power area, for 

example, the risk metric is based on core damage frequency (CDF) – not on fire in particular. The CDF is 

a political ‘risk tolerance’ criteria, in the USA set by the Nuclear Regulatory Commission (NRC), and 

reflects an unacceptable outcome from any ‘acute event’ (e.g., accidental failure, earthquake, attack, 

whatever – not just fire), and the fire risk assessment component focuses on potential for a fire in either a 

‘functional zone’, such as turbine hall or control room, or a fire in a ‘utility zone’, such as a cable vault or 

switchgear room, to result in an unacceptable outcome. The ‘targets’ in the analysis are then any system 

or component that could lead to CDF, including cables, control equipment, operators, etc. 

More detail on the framework and component parts can be found in the associated references and annexes 

to this report. In addition, a few critical issues and associated further research needs as outlined in 

Sections 6 and 7 that follow. Section 8 discusses data used and developed as part of the framework 

development, with Section 9 overviewing the web-based test-bed environment discussed above. 

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6 

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Risk Characterization and Analysis Issues 

Tools and techniques for fire risk analysis are fairly well developed (e.g., see [22]). However, guidance 

and techniques for fire risk characterization, while discussed in the literature and in guidance documents 

in broad terms [22-26], is lacking at a detailed level. A possible path forward has been identified as part 

of this research [1] but was not able to be advanced within the period of study. The proposed approach is 

briefly overviewed below. 

Since risk characterization metrics are tied to the systems they represent, a possible formulation for these 

metrics is a fraction, where the numerator deals with the fire events in a defined period of time and the 

denominator describes a relevant parameter of the system. Different objectives may be considered by the 

different stakeholders. All stakeholders are concerned by life safety so the metric numerator should 

include parameters dealing, for example, with annual deaths and injuries caused by fires affecting the 

considered systems; the denominator would include some information relevant to the activity of the 

occupant in the considered building. For property protection, the numerator of the corresponding metric 

could include parameters describing, for example, the amount of damage due to fires, including direct and 

indirect fire damage. For business interruption, the metric numerator could include the number of days 

lost in production due to fire events in similar industrial systems. This approach was taken by Kobayashi 

and Nozaki [27]. Table 1 presents their findings related to commercial buildings, defined in terms of four 

different classes based on floor area and number of stories. Figure 7 presents the corresponding fire risk 

with an estimation of the damage area as a function of annual exceedance of probability. 

Table 1. Calculations conditions for example risk curves [27] 

Classification Median floor area (m2) Median Number of Stories 

Group "H" 36,597 10 

Group "LL" 31,124 5 

Group "LM" 11,239 4 

Group "LS" 2,148 2 

Group "H"
 

Group "LL"
 

Group "LM"
 

Group "LS"
 

Figure 7. Example of fire risk curves for commercial buildings [27] 

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Risk matrix or fire risk curves such as the one presented in Figure 7 can be established for ‘buildingoccupant’ systems, based on the corresponding fire statistics which describe the appropriate metric for 

each objective considered by the project stakeholders. For example, Tsujimoto [28] presented fire risks to 

Japanese occupants in residential buildings, hospitals and hotels from 1969 to 2000, as annual deaths per 

105 users’ year stays in each kind of place with the corresponding metrics: 

Residential buildings: annual deaths by residential fires 

population 

annual deaths by hospital fires Hospitals: (total number of sickbeds in Japan) x (annual used rate) 

annual deaths by hotel fires Hotels: annual total number of hotel guests 

Based on these metrics, he presented the death risk a person takes at one night in each place: 

4 Residence Hospital Hotel 

3.5 

3 

2.5 

2 

1.5 

1 

0.5
 

0
 

Year 

Figure 8. Death risk trends in selected Japanese buildings between 1969 and 2000 [28] 

Particular care should be taken when aggregating buildings into a similar category. This situation is not 

only due to the evolution with time of building characteristics (e.g. open space office floors versus 

compartmented office floors) but also due to the evolution with time of building code prescriptive 

requirements regarding fire safety. For example, Tsujimoto [29] also looked at establishing a correlation 

between fatalities in hospitals and the number of beds with or without sprinklers. 

Table 2. Transition of Requirement for Sprinkler Installation of Hospital (Fire Code in Japan) [28] Annual Death / 105 Users/Year 

1970 1975 1980 1985 1990 1995 2000 

1961.4 patients room over 4th floor ≧ 1500 m2 

1967.7 4th floor to 10th floor; floor area more than 100 m2 over 11th floor 

1973.6 total floor area is over 6000 m2 except one-story hospital; over 11th floor; floor area more than 

1000 m2 which floor is underground or without window 

1974.6 retroactive application to existing building 

1988.4 total floor area is over 3000 m2 except one-story hospital 

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180 36 

160 32 

Total number of beds 

Number of beds without sprinkler 

Fatalities of hospital fires (person / year) 

140 28 

Fatalities of hospital fires (person / year) 

Total number of beds (x10,000) 120 24 

100 20 

80 16 

60 12 

40 8 

20 4 

0 0 

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 

Year 

Figure 9. Correlation between Fatalities in Hospital and Number of Beds [28] 

It should be noted that some information output collected while performing research for the risk 

characterization Step (e.g. information related to the characterization of fires and of the considered 

systems) can be used as input for the next steps related to fire risk analysis (fire likelihood and fire 

consequence evaluation). For example, while assessing information about fire statistics and past fire 

events, elements of information related to scenarios, fire ignition, fire propagation in terms of frequency 

and intensity of damage should also be collected. Also, within the ‘building-occupant’ system paradigm, 

characteristics of the different types of systems should also be collected so to have more information 

about the potential targets located inside the different parts of the systems. 

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7 

Risk-Informed Performance-Based Design 

Consequence Analysis Issues 

Most fire protection engineers (FPEs) are familiar with consequence analysis in terms of estimating 

outcomes of fire scenarios via fire effects modeling and evacuation modeling, and in some cases 

explosion analysis, structural response analysis and other specialized tools. However, as the use of 

computational tools for consequence analysis increases, there are associated concerns with predictive 

capability of the tools, both in terms of the tool itself and with respect to user decisions, including 

selection of the appropriate tool for the problem, selection of appropriate input data, proper 

characterization of the reliability of the prediction given uncertainty and variability of the input, and 

adequately linking dynamically-related issues, such as occupant influence on fire growth and spread 

during evacuation and how that is modeled [1, 8]. In a risk-informed environment, various techniques can 

be applied to address variability in the overall risk prediction, as discussed in Section 5 (e.g., see [16-22]). 

However, at the consequence analysis stage, it is still important to develop reliable estimates. 

As discussed in [7-9], the reliability of estimates can be increased with selection of the right tool for the 

problem, having reliable and consistent characterizations of the design fire, and taking care to integrate 

between fire-people-building interactions in the analysis. With respect to selecting the right tool, the 

decision should be made in the context of the level of accuracy needed in the prediction, predictive 

capability of the tool, and the availability of input data that is representative of the scenario being 

modeled. These issues are impacted by knowledge and time. As such, the ‘right tool for the job’ might 

change as a project develops. At the start of the project, in the feasibility and concept design phases, the 

level of detail in the analysis is quite low as the FPE can only provide an idea of the measures to install 

(based on the prescriptive requirements and the possible deviations to them) as data required to perform 

any analysis is still scarce. If fire effects tools are needed, algebraic models are mainly used, with a high 

calculation speed. During the scheme design, data related to the interior design of the building becomes 

available and more sophisticated tools can then be used, such as zone models. In the detailed design 

phase, the details of the project are known and 3-D simulations can be used – if needed and if time allows 

– as the time for analysis is shorter as we go along the project, running these complex simulations 

requires a considerable amount of time, compared to the use of previous tools, and since these tools 

generate a lot of useful information, data treatment of 3-D simulations is also time consuming. 

Zone model use 

domain 

Algebraic model use domain 

Feasibility Concept Scheme Detailed time 

y 

Availability of data

CFD 

model 

use 

Time for analysis 

domain 

Figure 10. Fire effects tools domains as a function of a new building project phases [7] 

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Risk-Informed Performance-Based Design 

Figure 10 is applicable to the whole building project. If a specific safety point is known at the concept 

design phase, and if it is also known that the degree of details would require a more complex tool than an 

algebraic model or even a zone model, the FPE would have to somehow obtain, from the design team, the 

data needed in order to use such a more complex tool at the earlier stage. As stated previously, performing 

such calculations uses significant time and resources and the results are highly dependent on the input 

parameter values. Using input parameter values at the start, which in the end would be quite different 

from the ones that would be finally needed, could lead to dramatic changes in the design, not only of the 

fire protection features but also in the design of the building itself, and could mean expending 

considerable resource for limited value. 

However, if a set of 'test bed' studies existed, which reflect similar projects, the information could place 

the FPE in a better position to ask the design team for needed input parameter values, or at least range of 

values, based on the experience of the test bed studies. This is one focus of the Vulcan Initiative (see 

Section 9), where on-line test-bed environments are envisioned to allow engineers to gain experience on 

determining what level of sophistication of tool is needed for what type of problem by conducting various 

exercises, and to obtain parameter values based on the exercises. An example of a parameter study which 

uses this concept is described in [29]. 

With respect to selecting design fires, there is a concern that while some sources of data exist, such in the 

SFPE Handbook of fire Protection Engineering, there can be inconsistency in which materials and 

associated heat release rate curves one selects (e.g., see [30], the format required for implementation of 

the HRR curve and related fire parameters into different tools, and the proper implementation by the user 

of the curve and associated data into a tool [6-9]). To help address these issues, data has been collected on 

fuel packages for use in fire effects modeling (see Section 8) and a test-bed environment is being created 

via the Vulcan Initiative (see Section 9). 

Finally, it is important that while the future is integrated tools capable of managing fire and egress 

modeling, fire and structural effects, and until then, engineers need to develop guidelines on how to 

conduct the dynamic analysis which integrates fire-people-building interactions throughout the analysis 

process. 

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Risk-Informed Performance-Based Design 

8 Data 

Risk-informed performance-based design is necessarily data driven. While some data sources exist, such 

as NFPA statistics on fires by occupancy types, or heat release rate curves in the SFPE Handbook of Fire 

Protection Engineering, the discipline still generally lacks qualified data for use in fire engineering 

analysis. In this project, the team looked at developing a mechanism to facilitate collection and use of 

data of all types – building configurations for analysis, fire frequency data, heat release rate curves, and 

more – in an environment that is readily accessible to practicing engineers, and which can be added to by 

practicing engineers, researchers and others. The mechanism is the Vulcan Initiative, as described in 

Section 9. Along the way, however, data of various types was gathered, in part to populate the initial 

generation of the Vulcan Initiative and well as to illustrate to others the type and level of data and 

information being sought to enhance the effort. 

8.1 Building Geometries 

This effort resulted in the collection of the following representative building configurations for use in 

performance-based analyses within the test-bed environment: 

•	 A 5-story library, including shelves, individual booths, classrooms, storage areas, etc. 

•	 A 3-story dormitory building including sleeping rooms, kitchen areas, etc. 

•	 The reconstruction of the Station Nightclub, based on the simulations performed by NIST in the 

NCSTAR reports 

•	 A two-story duplex based on the simulations performed by NIST in the Keokuk fire investigation 

•	 A high rise hospital including patient floor, operating rooms, intensive care units, cafeteria, and an 

atrium 

•	 A one-story hospital 

•	 Several high-rise office buildings 

Several of these building configurations have been formatted for fire effects analysis using FDS or other 

fire effects tools, as well as for evacuation analysis with two different evacuation tools (Pathfinder from 

Thunderhead Engineering Consultants and STEPS from Mott MacDonald Group). These building 

configurations will be available via the Vulcan Initiative website. 

8.2 Design Fire Data 

As part of this project, a “HRR catalog” in the form of an Excel spreadsheet has been established to be a 

free repository of information about one of the major components of risk-informed performance-based 

design: the Heat Release Rate (HRR) of a fuel item. One of the main sources of HRR data embodied in 

the HRR Catalog is the chapter by Vytenis Babrauskas in the SFPE Handbook of Fire Protection 

Engineering (Section 3, Chapter 1 for the 4th edition). The objective for the HRR catalog is to collect heat 

release rates of “real products” or items that could be considered in an engineering analysis requiring fire 

modeling. Thus, the HRR catalog contains HRR evolution with time (called “HRR curves”) of mattresses 

and wardrobes or of office worker cubicles that could be used to assess the consequences of a fire in a 

hotel guestroom or an office open space, respectively. 

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The origin of the HRR catalog came after noticing that even if the SFPE Handbook chapter is unmatched 

in terms of extent of data it provides (as it includes real products alphabetically ranging from beddings to 

windows made of plastics), its printed format could be improved in the era of information technology. For 

instance, publication restrictions of the SFPE Handbook generate updates every few years (3rd edition: 

2002, 4th edition: 2008) and it is not practicable to devote hundreds of pages on this particular but 

essential topic in a single book covering all the aspects of fire protection engineering. As a result, it was 

thought that providing information on the Internet would remove these restrictions in terms of space and 

content update. Attempts were made and webpages can be found but, unfortunately, instead of expanding 

the paper format, these webpages condensed even more the information presented in the SFPE Handbook 

under the form of tables. 

Within the Vulcan Initiative, participants would have the opportunity to help implementing a database or 

catalog for heat release rates. A more pragmatic approach than a webpage configuration has been taken so 

that the information would not be contained (and therefore restricted) to the limits of webpage 

visualization but expended, as needed in separated and self-supported files. By its own nature, the heat 

release rate data is graphic and consists of the evolution of the HRR with time. Other information related 

to the test performed to obtain the HRR data can be associated with parameters such as the nature of the 

test, time to the maximum HRR or if additional measurements were made during the test (soot, CO...). 

As a consequence, it was decided to use a Microsoft Excel spreadsheet to gather all the information 

regarding heat release rates of real products. Excel presents the advantage to be relatively easy to use, 

widely known in Academia and work environment and with the latest version, it is possible to share the 

same document “on the Cloud” so that a single document is used and can be updated by multiple 

participants of the Vulcan Initiative. 

The organization of the contents of the HRR catalog spreadsheet, and how a participant to the Vulcan 

Initiative can help implementing it for the benefits of the Fire Protection Engineering community, is 

provided in Annex F. 

In addition, a ‘Test_HHR_Catalog_raw_data” (raw data) spreadsheet has been developed. The Test HRR 

spreadsheet expands on work by a WPI student [31], who had collected approximately 50 heat release 

rate curves and associated information. Students in the Performance-Based Design course at WPI were 

asked to add HRR curves. However, many of the students deviated from the given format so a decision 

was made to compile all of the HRR curves into a single spreadsheet of ‘raw data’ to be formatted at a 

later time. This ‘raw data’ spreadsheet contains more than 200 potential items, which can be formatted to 

the now established templates included in the HRR_Catalog spreadsheet. The ‘raw data’ spreadsheet is 

submitted as to prove how potentially efficient collaboration can be between the engineering community 

who needs easy to use data and Academia who has the resources to deliver such data. Students joining the 

engineering community would also know that this data exists and how to use it. 

The ‘HRR catalog’ and ‘raw data’ spreadsheets are provided separately. 

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9 

Risk-Informed Performance-Based Design 

Vulcan Initiative 

The Vulcan Initiative was created as a way to facilitate the establishment of guidelines for each technical 

step of the new risk-informed performance-based design process as elaborated in this report. In brief, it is 

a web-based portal where participants can access data, conduct analyses in test-bed environments, and 

upload data for use by others. The Beta web site contains the structure with which one can upload a 

‘project’ for analysis and selected input sheets for data. A project contains the characteristics of a 

‘building occupant’ system, such as the building layout, the list of stakeholder targets. 

In the Vulcan Initiative, one participant willing to apply the new PBFPD process for a particular project 

will successively go through the following components: fire risk characterization will include databases 

on fire statistics and on the census of specific systems, fire damage criteria will include databases on how 

fire can affect people and building contents that are relevant to stakeholders for property protection or 

business continuity objectives. Fire risk analysis will include tools to assess the likelihood and the 

consequences of fires, as well as their corresponding databases relative to fire ignition frequencies, 

reliability of fire protection measures, production of heat and fire effluents from combustible packages, 

human behavior and structural response. Cost-benefit analysis will include tools to assess the cost of 

installing and maintaining fire protection measures in specific systems. 

Participants to the Vulcan Initiative are welcome to upload the projects of their choice, at the present time 

even if there is still a lot of research to be undertaken to complete the guidelines. By doing so, they will 

provide needed input data which could be used for 'test bed' environment studies described above. By 

sharing the characteristics of their system and presenting the issues related to their project, these "project 

owners" could be joined, in the short term, by others in the Fire Protection Engineering community 

having the same issues. On the long term, they will ultimately benefit from the results of the studies as 

these results will be applied to their own project or similar projects (see Figure 11). 

Tasks related to a "project" 

Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 

"Project owner" 

uploads input data 

(system 

"Project" participants 

get the results of the 

PBFPD process 

"Project" participants can help for one or several of the PBFPD process steps 

Figure 11. Organization of a "project" in the Vulcan Initiative [9] 

Examples of projects included in the Vulcan Initiative site include a hospital, a high-rise hotel and a mall, 

created in academia, from the Worcester Polytechnic Institute (WPI), USA. The 5-story hospital was 

based on an actual building design, modified with specific features such as a ‘function space,’ so as to 

allow students experience in assessing different fire scenarios and evacuation, protect in place and 

relocation scenarios. The 30-story high-rise hotel with associated convention space was developed at WPI 

to provide an environment within which to have students assess such factors as fire scenarios, evacuation 

schemes and mitigation measures (such as smoke exhaust in atria and meeting spaces). The 3-story 

shopping mall was likewise developed at WPI to have students assess such factors as fire scenarios, 

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Risk-Informed Performance-Based Design 

evacuation schemes and mitigation measures (such as smoke exhaust and material control). These 

projects can serve as examples for future students, and new projects could be added to the Vulcan 

Initiative using these configurations and associated data. WPI hopes to be joined by other institutions 

around the world, as well as tool developers, architects, code officials and others, from whom advice 

could be requested and interaction in the virtual environment can help address 'real world' issues and 

facilitate development of new detailed guidelines as outlined above. 

The structure of the Beta version of the Vulcan Initiative website (http://www.vulcaninitiative.net/index.html) can be found in Annex G and H. It is expected that the Vulcan Initiative website 

will be modified extensively in the coming years. 

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Risk-Informed Performance-Based Design 

10 Outcomes, Ongoing Efforts and Recommended Future Research 

As with any research effort, what can be done within a particular period of effort does not reflect the 

totality of the impact and opportunities which follow the initial efforts. Such is the case with this project, 

where outcomes are just beginning to influence future direction, ongoing efforts are underway to further 

develop concepts, and pathways for future research in this area have been developed. 

10.1 Outcomes 

This report has summarized the major outcomes from this research effort. In brief, a new framework for a 

risk-informed performance-based approach to fire safety analysis and design has been proposed. It is 

structured around a paradigm in which the performance analysis is conducted relative to the performance 

of a building-occupant system within a broader context of the managing risk of an acute event (e.g., fire) 

on the chronic state of the system. It proposes development of specific guidance for building-occupant 

systems, nominally structured around real building occupancy and daily use issue, which: 

•	 Provide detailed directions as to how to characterize the risk 

•	 Adequately identify targets and vulnerabilities, both direct and in-direct, 

•	 Better assess and mitigate the likelihood of disruptive events impacting the desired performance of 

the building-occupant system, and 

•	 Develop mitigation strategies which are cost-effective within the context of the overall buildingoccupant system. 

In addition, a test-bed environment has been proposed – the Vulcan Initiative – with a Beta version web 

portal developed, to facilitate a common location for data and information in support of risk-informed 

performance-based design. A key feature of the website when completed will be the ability for 

practitioners, students and others to interactively use building geometries, data and analysis tools to gain 

and share experiences in the application of the new process. 

To support the use of the web-based test-bed environment, data have been collected and made available 

on heat release rate curves and associated information as part of a database on design fire curves, and a 

selection of building geometries for use fire effects, evacuation and other modeling and analysis have 

been compiled. Case studies related to test-bed environments are being assembled as well. 

To date, more than ten publications have been developed as part of disseminating information about the 

development of the framework, the paradigm shift, the test-bed environment and the web portal. 

10.2 Ongoing Efforts 

Even though the funded part of this effort is now over, unfunded work by various team members 

continues to be undertaken due to their dedication to the advancement of the concepts and dissemination 

of information developed in this project. Work continues, for example, on guidance for risk 

characterization, development of HRR data, parametric studies [29], and collection of geometries and 

case study examples for use in the Vulcan Initiative test-bed environment. 

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Risk-Informed Performance-Based Design 

In addition, concepts related to risk characterization, focus on targets and vulnerability criteria for targets, 

better characterization of scenarios of concern based on risk characterization, and more robust data for 

design fire characterization have been introduced to the SFPE Standards Committee on Design Fire 

Scenarios for consideration in development of future standards. Similarly, discussions have been held 

with members of ISO TC92 SC4 with the aim of introducing outcomes of this research into the ISO 

standards on fire safety engineering. 

10.3 Recommended Future Research 

There are several areas which need additional research and development to facilitate adoption and use of 

the new framework for risk-informed performance-based design for fire. 

The Vulcan Initiative and associated web portal need to be advanced and developed to facilitate its use as 

a repository and access point to guidance, data, tools and test-bed environments and outcomes in support 

of risk-informed performance-based design for fire. Ideally a sponsor, such as the Society of Fire 

Protection Engineers, NIST or other, who sees benefit to the portal, will be able to assist and perhaps take 

over management of the site in the future. 

A better-defined approach to risk characterization is needed. While the foundations have been laid in 

terms of the building-occupant system and disruptive event paradigm, guidance for how stakeholders can 

appropriately characterize fire risk within this paradigm is needed. 

Data on frequency of fire ignition, spread and impact are needed, as are data on system reliability and 

availability. While national data, such as from the NFIRS system on number of fires per year helps, it is 

often presented by occupancy groups that lump distinct “building-occupant” systems. Besides, more data, 

such as is available in the insurance industry, is needed to estimate performance indicators related to 

property protection and business continuity, as well as fire protection system reliability and efficiency. 

This is for the risk characterization as well as the risk analysis components 

Guidance on development of scenarios and quantification of design fires for use in analysis is needed. 

While efforts such as those by the SFPE Standards Committee on Design Fire Scenarios are tackling this 

within the construct of the existing PBD paradigm, different guidance is needed for use within the 

building-occupant system and disruptive event paradigm. In fact, guidance (and data) relative to each step 

of the new framework – focused on specific building-occupant systems – is needed. (The Vulcan 

Initiative and associated web portal is hoped to be one mechanism for facilitating development of this 

guidance). 

Ultimately, as data are collected, case studies undertaken, and experience is gained within the Vulcan 

Initiative, specific recommendations for code changes relative to building risk and performance levels, 

target vulnerability criteria, design fires and more can be developed. 

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Risk-Informed Performance-Based Design 

11 Summary and Conclusions 

Performance-based building codes have been implemented in numerous countries world-wide. In 

addition, performance-based approaches to fire safety analysis and design are widely used, both in 

countries with performance-based building codes as well as those with prescriptive-based codes. 

However, most building codes – prescriptive- or performance-based – lack quantitative risk, safety or 

performance criteria, and decisions regarding acceptance criteria often rests with the fire protection 

engineer and design team, often with no benchmarking against other buildings. As a result, there is a high 

degree of variability in fire engineered building design solutions and in the review and approval of these 

solutions, and therefore in the levels of fire safety provided in buildings that have been designed using 

performance methods. There have been few fire-related failures that can be attributed to “unacceptable” 

fire safety performance being delivered under the current performance-based fire safety design 

framework. However, performance failures under prescriptive codes and in other regulated areas, 

perceived quality concerns, and a desire to be more transparent have motivated several countries to try 

and better understand and quantify the level of fire safety and performance being provided in deemed-tosatisfy solutions (acceptable solutions, approved documents) and to establish quantitative measures for 

use in next generation performance-based building codes and performance-based fire safety design 

approaches. 

In order to help address issues of risk and performance quantification, this effort has advanced a new 

framework for a risk-informed performance-based approach to fire safety analysis and design. It is 

structured around a paradigm in which the performance analysis is conducted relative to the performance 

of a building-occupant system within a broader context of the managing risk of an acute event (e.g., fire) 

on the chronic state of the system. It proposes development of specific guidance for building-occupant 

systems, nominally structured around building use and occupancy issue, which provide detailed directions 

as to how to characterization the risk, adequately identify targets and vulnerabilities, both direct and indirect, better assess and mitigate the likelihood of disruptive events impacting the desired performance of 

the building-occupant system, and develop mitigation strategies which are cost-effective within the 

context of the overall building-occupant system. 

In addition, a test-bed environment has been proposed – the Vulcan Initiative – with a Beta version web 

portal developed, to facilitate a common location for data and information in support of risk-informed 

performance-based design. A key feature of the website when completed will be the ability for 

practitioners, students and others to interactively use building geometries, data and analysis tools to gain 

and share experiences in the application of the new process. 

To support the use of the web-based test-bed environment, data have been collected and made available 

on heat release rate curves and associated information as part of a database on design fire curves, and a 

selection of building geometries for use fire effects, evacuation and other modeling and analysis have 

been compiled. Case studies related to test-bed environments are being assembled as well. 

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References 

1.	 Alvarez Rodriquez, A., An Integrated Framework for the Next Generation of Risk-Informed 

Performance-Based Design Approach Used in Fire Safety Engineering, PhD Dissertation, Worcester 

Polytechnic Institute, December 2012 (to be published as NIST GCR, in press, NIST, Gaithersburg, 

MD, USA). 

2.	 Sheffi, Y., The Resilient Enterprise, Massachusetts Institute of Technology Press, 2005. 

3.	 Alvarez, A., Meacham, B.J., Dembsey, N.A. and Thomas, J.R., “20 Years of Performance-Based Fire 

Protection Design: Challenges Faced and a Look Ahead,” Journal of Fire Protection Engineering, 

DOI: 10.1177/1042391513484911, on-line 24 July 2013: print Vol. 23, No. 4., November 2013. 

4.	 Alvarez, A., Meacham, B.J., Dembsey, N.A. and Thomas, J.R., “A Framework For Risk-Informed 

Performance-Based Fire Protection Design For The Built Environment,” Fire Technology, DOI: 

10.1177/1042391513494923, Vol. 50, pp161-181, 2014. 

5.	 International Building Code, International Code Council, Washington, DC, 2012. 

6.	 Alvarez, A. and Meacham, B.J., “Towards and Integrated Performance-Based Design Approach for 

Life Safety across Different Building Use Groups,” proceedings, Interflam 2010, Interscience 

Communication, Ltd., London, July 2010. 

7.	 Alvarez, A. and Meacham, B.J., “’Ready-to-Use’ Building Layouts and Combustible Packages for 3­

D Fire Simulations,” Proceedings - Fire and Evacuation Modeling Technical Conference, Baltimore, 

MD, 16 August 2011. 

8.	 Alvarez, A. and Meacham, B.J., “'Test bed' Environment Process for Assessing the Appropriateness 

of Engineering Tools to be Used in Performance-Based Design Applications,” Proceedings, 9th SFPE 

International Conference on Performance-Based Codes and Fire Safety Design Methods, SFPE, 

Bethesda, MD, June 2012. 

9.	 Alvarez, A., Ferreira, M.A. and Meacham, B.J., “The VULCAN INITIATIVE: a web platform for the 

next generation of performance-based fire protection design,” Proceedings, Interflam 2013, 

Interscience Communication, Ltd., London, June 2013. 

10. Meacham, B.J., “International Experience in the Development and Use of Performance-Based Fire 

Safety Design Methods: Evolution, Current Situation, and Thoughts for the Future,” Invited Paper, 

Proceedings of the International Association for Fire Safety Science, 6th International Symposium, 

Poitiers, France, July 1999, pp.59-76. 

11. Meacham, B.J., “The Evolution of Performance-Based Codes and Fire Safety Design Methods,” GCR 

98-763, NIST, Gaithersburg, MD, 1998. 

12. Meacham, B.J., Moore, A., Bowen, R. and Traw, J., “Performance-Based Building Regulation: 

Current Situation and Future Needs,” Building Research & Information, Vol. 33, No. 1, pp.91-106, 

2005. 

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Risk-Informed Performance-Based Design 

13. Boutin, V. and Meacham, B.J., Comparison of the International Fire Engineering Guidelines, SFPE 

Engineering Guide on Performance-Based Fire Protection, BS7974 – Application of Fire Safety 

Engineering Principles to the Design of Buildings and ISO 13387 - Fire Safety Engineering – Part 1: 

Application of Fire Performance Concepts to Design Objectives, WPI, Worcester, MA, January 2013 

(to be published as a NIST GCR – awaiting number). 

14. Alvarez, A., Meacham, B.J., Dembsey, N.A. and Thomas, J.R., “Using A Systems Approach to 

Assess How Disruptive Events Affect Building Overall Performance,” unpublished manuscript, for 

submittal to Building Research & Information. 

15. Knight, R.F.	 and Pretty, D.J., The Impact of Catastrophes on Shareholder Value, The Oxford 

Executive Research Briefings. Templeton College, University of Oxford, England. 

16. Notarianni, K.A and Parry, G., “Uncertainty,” Section, 5, Chapter 4, SFPE Handbook of Fire 

Protection Engineering, NFPA, Quincy, MA, 2008 

17. Baker, G., Wade, C., Spearpoint, M. and Fleischmann, C., “Developing Probabilistic Design Fires for 

Performance-based Fire Safety Engineering,” 9th Asia-Oceana Symposium on Fire Science and 

Technology, Procedia Engineering, Vol. 62, pp639-647, 2013. 

18. Lord, J., Meacham, B.J., Moore, A., Fahy, R. and Proulx, G., Guide for Evaluating the Predictive 

Capability of Computer Egress Models, NIST GCR 06-886, National Institute of Standards and 

Technology, Building and Fire Research Laboratory, Gaithersburg, MD, December 2005. 

19. Albrecht, C., “Quantifying life safety: Part I: Scenario-based quantification,” Fire Safety Journal, 

Vol. 64, pp87-94, 2014. 

20. Albrecht, C., “Quantifying life safety: Part II: Quantification of fire protection systems,” Fire Safety 

Journal, Vol. 64, pp81-86, 2014. 

21. Albrecht, C. and Meacham, B.J., “Risk-Informed and Performance-Based Life Safety Design in 

Atrium-Type Buildings,” Proceedings, 10th International Conference on Performance-Based Codes 

and Fire Safety Design Methods, SFPE, Bethesda, MD, 2014. 

22. Meacham, B.J., Johnson, P.J., Charters, D. and Salisbury, M., “Building Fire Risk Analysis,” Section 

5, Chapter 12, SFPE Handbook of Fire Protection Engineering, 4th Ed., NFPA, Quincy, MA, USA, 

December 2008. 

23. Meacham, B.J., “Understanding Risk: Quantification, Perception and Characterization,” Journal of 

Fire Protection Engineering, Vol. 14, No. 3, pp.199-228, 2004. 

24. SFPE Engineering Guide – Fire Risk Assessment, Society of Fire Protection Engineers, Bethesda, 

MD, November 2006. 

25. ISO 16732-1:2012, Fire Safety Engineering—Guidance on Fire Risk Assessment, International 

Organization for Standardization (ISO), Geneva, Switzerland. 

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Risk-Informed Performance-Based Design 

26. BS 7974-7, “Part 7—Probabilistic Risk Assessment,” Code on the Application of Fire Safety 

Engineering Principles to the Design of Buildings, British Standards Institute, London, UK. 

27. Y. Kobayashi and H. Nozaki, A Statistical Method to Evaluate Fire Risks in Non-Residential 

Buildings in Japan," in: Fire Safety Science: Proceedings of the Eight International Symposium, 

China, International Association for Fire Safety Science, 2005, pp. 341-352. 

28. M. Tsujimoto, Death Risk by Building Fires in Japan and its Usage, Fire Science and Technology, 

vol. 23, no. 4, 2004, pp. 304-311. 

29. Alvarez-Rodriquez, A., Meacham, B.J. and Almejmaj, M., “A Parametric Multi-Tool Study to Assess 

Smoke Management System Performance for an Atrium,” to be published in Proceedings, SFPE 10th 

International Conference on Performance-Based Codes and Fire Safety Design Methods, Surfers 

Paradise, Australia, 12-14 November 2014. 

30. Fleischmann, C.M.,	 “Is Prescription the Future of Performance Based Design?” Fire Safety 

Science 10: 77-94. 10.3801/IAFSS.FSS.10-77 , 2011. 

31. WPI Graduate Independent Study Project, Arthur Gager, 2011. 

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Risk-Informed Performance-Based Design 

Annexes
 

Grant 60NANB10D228 39 Final Report 
 

Annex A
 

An Integrated Framework for the Next Generation of Risk-Informed
 

Performance-Based Design Approach Used in Fire Safety Engineering
 

Ph.D. Dissertation, Alberto Alvarez, ©2012 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

AN INTEGRATED FRAMEWORK FOR THE
 

NEXT GENERATION OF RISK-INFORMED PERFORMANCE-BASED 

DESIGN APPROACH USED IN FIRE SAFETY ENGINEERING
 

by 

Alberto ALVAREZ RODRIGUEZ 

A Dissertation Submitted to the Faculty of the 

WORCESTER POLYTECHNIC INSTITUTE 

in partial fulfillment of the requirements for the 

Degree of Doctor of Philosophy
 

in
 

Fire Protection Engineering
 

December 2012
 

APPROVED:
 

Dr. Brian J. Meacham, Major Advisor
 

Department of Fire Protection Engineering
 

Dr. Nicholas A. Dembsey, Advisor
 

Department of Fire Protection Engineering
 

Dr. Russell Thomas, Advisor
 

National Research Council, Canada
 

Dr. Kathy A. Notarianni, Department Head
 

Department of Fire Protection Engineering
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ABSTRACT
 

Review of decades of worldwide experience using standards, codes and guidelines related to performance-based fire 

protection design for buildings has identified shortcomings in the interpretation, application and implementation of 

the performance-based design process, wide variation in the resulting levels of performance achieved by such 

designs, and several opportunities to enhance the process. While others have highlighted shortcomings in the past, as 

well as some ideas to enhance the process, it is proposed that a more fundamental change is needed. 

First, the political and technical components of the process need to be clearly delineated to facilitate better analysis 

and decision-making within each component. Second, the process needs to be changed from one which focuses only 

on fire safety systems to one which views buildings, their occupants and their contents as integrated systems. In 

doing so, the activities associated with the normal operation of a building and how they might be impacted by the 

occurrence of a fire event become clearer, as do mitigation options which account for the behaviors and activities 

associated with normal use. 

To support these changes, a new framework for a risk-informed performance-based process for fire protection 

design is proposed: one which is better integrated than current processes, that treats a fire event as a disruptive event 

of a larger and more complex "building-occupant" system, and that provides more specific guidance for engineering 

analysis with the aim to achieve more complete and consistent analysis. 

This Ph.D. Dissertation outlines the challenges with the existing approaches, presents the "building-occupant" 

system paradigm, illustrates how viewing fire (or any other hazard) as a disruptive event within an holistic 

"building-occupant" system can benefit the overall performance of this system over its lifespan, and outlines a 

framework for a risk-informed performance-based process for fire protection design. Case studies are used to 

illustrate shortcomings in the existing processes and how the proposed process will address these. This Dissertation 

also includes a plan of action needed to establish guidelines to conduct each of the technical steps of the process and 

briefly introduces the future work about how this plan could be practically facilitated via a web-platform as a 

collaborative environment. 

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EXECUTIVE SUMMARY
 

Performance-based design (PBD) approaches are being developed for numerous engineering disciplines, including 

mechanical, structural, and fire protection engineering. Allowed nowadays in the building regulatory framework of 

more and more nations, the application of these approaches has made possible real innovative and aesthetically 

pleasing as well as safe, efficient and cost-effective building designs. 

However, PBD approaches are still not as widely applied as some predicted two decades ago. In part, this is because 

the political and technical aspects of PBD have been intertwined. This creates challenges as approaches and 

solutions to political and technical challenges can be quite different. 

The decision to apply PBD approaches instead of following the prescriptive requirements of building codes is a 

political choice agreed among the different building stakeholders, who may have different (if not competing) 

objectives related to the buildings performance. In addition, final selection of a design option is also a political 

decision, in this case of the client, which should be informed by engineering analysis but not made by the engineer. 

In the political sense, then, the application of current PBD approaches for fire remains limited, as: 

- The building design team can be reluctant to use a PBD approach, as when compared to the strict application of 

the prescriptive code requirements, it can be quite costly in terms of time and resources while its outcome may 

be rejected by enforcement officials, leading to more delays, more spending and alterations of the initial design. 

- The regulators and enforcement officials express various concerns with PBD, including: 

	 Selection and use of performance criteria, which should be a policy decision, but is currently largely a 

technical decision made by the FPE, usually with agreement of project stakeholders, as they are not 

regulated. 

	 The comparison of a building safety level established through application of a PBD approach with the one 

established by the prescriptive requirements. 

	 The validation of the tools, data and methods used in the PBD approach. 

On the technical aspect of fire protection engineering, it should be noted that while having a solid research base, this 

discipline has not yet reached a mature state. When academic programs started to be established in the 1970's, their 

main focus was to incorporate research results in the understanding of fire phenomena. Nowadays, they have added 

modules including risk concepts and human behavior. In spite of these abundant research results, the transfer of 

information from research into practice suffers from the inertia intrinsic to practitioners, policy makers and law 

enforcers when confronted with new engineering methods and concepts. 

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In the 2000's, the publishing of performance-based fire protection design (PBFPD) documents including guides and 

guidelines from fire protection engineering societies (e.g. Society of Fire Protection Engineers) or international 

committees (e.g. International Organization for Standardization or Inter-jurisdiction Regulatory Collaboration 

Committee) as well as codes and standards embodied in some national regulations (e.g. Sweden, New Zealand and 

Japan) appeared as a benefit but turned out to be a drawback to the dissemination of PBD approaches. For instance, 

the PBFPD processes currently included in codes, standards, guides and guidelines were written at a time when it 

was a priority to introduce the global concepts of the PBFPD process, to model all the phenomena, and to determine 

and assess the influence of critical components of the PBFPD process. With this purpose in mind, they had to be 

generic in order to be used as widely as possible. This generic attribute of all the PBFPD documents, initially 

looking for uniformity in the application of their respective PBFPD process, led to a diversity of results from fire 

protection engineers who, used to follow prescriptive requirements, might not fully understand how the generic 

concepts were to be applied to specific and innovative projects. 

As an engineering discipline, fire protection engineering relies on the utilization of tools and models in order to 

quantify relevant parameters describing the fire phenomena themselves, occupant evacuation and structural 

response. Since property protection, business continuity, heritage preservation and environmental protection are 

objectives of potential interest for a building project stakeholder, fire protection engineers, if not directly assessing 

relevant parameters unique for taking into consideration these objectives, still needs to communicate with the 

corresponding experts and to incorporate their assessment into their own assessment. In other terms, fire protection 

engineering has expanded to become a real inter-disciplinary field, which means that not only fire protection 

engineers have to keep up to date with fundamental research in their main disciplines (e.g. fire dynamics, fire 

modeling) but they are required to constantly expand their knowledge to other disciplines, as well as being aware of 

innovations occurring in the built environment with new materials and new construction practices. 

Engineering calculation methods are presented in only a few regulations, usually as recommended practice, but are 

limited to particular and isolated part of the whole engineering problem (e.g. temperature and velocity in an 

unobstructed and axisymmetric fire plume). Fortunately, along with the development of computer science, tools 

were developed to assess temperature profiles and smoke transport for simulated user-input fires, with more or less 

definition of the complexity of the building geometries (e.g. atrium space, multiple rooms and multiple floors) and 

specificities (e.g. mechanical ventilation). Evacuation tools, dealing with human behavior and structural response 

tools were also developed on their own. Unfortunately, all these tools provided with a more or less easy-toimplement graphic user interface, remain research tools with relatively limited validation domains, and their use in 

PBD application requires fire protection engineers to have a good understanding of the uses and limits of the tools, 

especially when they need to combine the different results from each tool for their global engineering analysis. User 

effects as well as the need to apply these tools for configurations they were not tested or designed for, raise 

skepticism and concerns from the authorities having jurisdiction when judging the validity of the PBD application 

process which is still largely dependent on the calculations performed with these tools. 

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Recognizing this wide range of expectations, concerns and challenges related to the use of current PBFPD 

processes, the research presented in this Ph.D. dissertation identifies a path forward for advancing performancebased fire protection design and the fire safety engineering profession, founded on three fundamental concepts: 

1.	 Fire protection engineers need to make a paradigm shift from one in which fire is the center of the problem, to 

one in which building performance metrics are evaluated in the case of fire events. This paradigm shift is 

necessary because current PBFPD guidelines are so focused on design fire scenarios, to the extent that fire 

protection measures deemed appropriate at the time of design might not be the most appropriate when 

implemented in a building, that key aspects of resultant fire protection designs might be ignored or worse 

"rejected" by the occupants of the building when needed the most, since fire is not a daily concern of building 

occupants. Fires, as with earthquakes, floods or even terrorism, instead have to be seen as one of many potential 

‘acute’ disruptive events that may occur during the ‘chronic’ lifespan of a building. In consequence, fire 

protection measures should be an integrated part of a "building-occupant" system formed by specific building 

types, the activities being undertaken in the buildings, and the building occupants in order to limit the effects of 

fire events on the overall performance of the system, which is the main concern of the system stakeholders. 

2.	 To assess the effects of fire or any other disruptive event on the overall performance of the building-occupant 

system, and result in a mitigation strategy which considers the impact of the ‘acute’ event within the ‘chronic’ 

lifespan of a building, a system-specific, risk-informed performance-based process has been established. This 

process clearly separates the technical aspect related to the tasks engineers have to perform (acute impact 

analysis) from the political aspect which determines the normal (chronic) performance expectations of the 

system stakeholders, including the level of degradation in building performance that the stakeholders would 

accept in the case where disruptive events affect their system. As a consequence of this separation, the technical 

stage of the process becomes transparent, both for stakeholders who establish the performance targets (political 

decision) and for the engineers in charge of the evaluation of the disruptive effects on the system performance 

(technical analysis). 

3.	 To facilitate the paradigm shift and successfully implement the new risk-informed, performance-based 

guidelines for use within the building-occupant systems framework, detailed guidelines are needed for a broad 

set of building-occupant systems. While development of such guidelines was outside of the scope of this Ph. D. 

research, since it requires the participation of many different actors, time and resources that are not compatible 

with a single Ph.D. program, a plan of action is proposed to facilitate creation of the guidelines for each of the 

technical steps of the risk-informed, performance-based process for specific "building-occupant" systems. As 

future work, a web-platform dedicated to facilitating and speeding up the execution of the plan, is being 

developed and will follow the publication of this Ph. D. dissertation. 

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ACKNOWLEDGEMENTS
 

I would like to thank all of those who have helped me in all aspects of this work. 

First and foremost, I would like to thank Prof. Brian J. Meacham, my WPI advisor, for sharing his expertise in the 

numerous fields he masters (Fire Protection Engineering, Risk Assessment and Code Making), for encouraging me 

in the development of new ideas and concepts, for providing me with a constant and endless guidance in his too 

busy and demanding schedule, and for trusting me with being one of his Teaching Assistants, with giving some 

lectures in his courses and with helping him design some course contents. This research would have been impossible 

without his unselfish support and patience. 

I would like to thank Prof. Nicholas A. Dembsey, my WPI co-advisor, for his feedback and comments that 

contributed to a more comprehensive presentation of a complex research. I would also like to acknowledge him as 

an outstanding instructor of fundamental fire research such as Fire Dynamics and Fire modeling. 

I would like to thank Dr. Russ Thomas, my co-advisor from National Research Council - Canada, for his outside 

perspective of a policy maker, so my research would resonate to others than Fire Protection Engineers and 

researchers. 

After more than a decade in the workplace, it was a great experience to be back in academia, especially in the Fire 

Protection Engineering Department directed by Prof. Kathy A. Notarianni. It was a life time opportunity to learn 

from dedicated and expert professors, as well as to be a Teaching Assistant (so to realize how deeply dedicated all 

the professors are). A special Thank to Sasha Strong, Catherine Fradette and Mary Racicot for their efficiency in 

taking care of all the official tasks. 

I would like to thank Mrs. Lynne Riley, from the George C. Gordon Library for helping me with copyright issues, 

referencing and for showing me all the useful material available to Fire Protection Engineers, online and offline. 

Being able to look through these resources allowed a very good start in my Ph.D. (or any) research. 

I would like to express hearty thanks to the other Ph.D. students in the "Thinker" team: Hae-Jun Park and Majed 

Almejmaj, for their highly valued help and bouncing ideas, as well as all the other students (Dr. Joel Sipe, 

Dr. Kulbhushan Arvind Joshi, Dr. Scott Rockwell, Mihyun (Ester) Kim, Jan Thomas, and Young-Geun You) who 

shared the cozy Ph.D. student office. 

I would like to thank the US National Institute of Standards and Technology (NIST) for supporting the research on 

which this present Ph.D. dissertation is based, under grant 60NANB10D228. 

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TABLE OF CONTENTS
 

1. Introduction.........................................................................................................................................................1
 

1.1 Context of the research .......................................................................................................................................1
 

1.2 Organization of the dissertation ..........................................................................................................................2
 

2. Twenty Years of Performance-Based Fire Protection Design: Challenges Faced and a Look Ahead ................5
 

2.1 Technical and political challenges related to the use of PBFPD processes.........................................................7
 

2.1.1 Technical challenges related to the use of PBFPD processes .............................................................................8
 

2.1.2 Political challenges related to the use of PBFPD processes................................................................................8
 

2.2 Detailed challenges of current PBFPD processes ...............................................................................................9
 

2.2.1 Challenges when applying generic guidance to specific projects .....................................................................11
 

2.2.2 Challenges associated with the definition, use and quantification of the performance/acceptance criteria ......12
 

2.2.3	 Challenges associated with the selection of fire design scenarios ....................................................................16
 

2.2.4	 Challenges when dealing with a priori lists of performance criteria and design fire scenarios ........................17
 

2.2.5	 Challenges when comparing levels of performance between an engineering solution and the one based on
 

prescriptive requirements..................................................................................................................................19
 

2.2.6	 Challenges related to the determination of influential factors affecting the evaluation of trial designs ...........21
 

2.2.7	 Challenges when dealing with "idealized" design features and "real life" installed and running features........21
 

2.2.8	 Challenges when estimating the consequences of fire design scenarios ...........................................................22
 

2.2.9	 Challenges when adapting literature values, when available, to use in models ................................................23
 

2.3	 Summary of the challenges related to the use of current PBFPD processes .....................................................25
 

2.4	 Characteristics of a new paradigm ....................................................................................................................28
 

2.5	 Conclusion of this chapter ................................................................................................................................29
 

3.	 Using A Systems Approach To Assess How Disruptive Events Affect Building Overall Performance ..........33
 

3.1	 Definition of the daily performance of a "building-occupant" system and its decrease during a disruptive
 

event..................................................................................................................................................................34
 

3.1.1	 Introduction of the "building-occupant" system paradigm ...............................................................................35
 

3.1.2	 Characterization of the effects of a disruptive event on the performance of a "building-occupant" system.....39
 

3.1.3	 Key-concepts of "building-occupant" systems .................................................................................................42
 

3.2	 Identifying and avoiding competing objectives within a "building-occupant" system .....................................43
 

3.2.1	 Fire safety objective competing with "chronic" objectives established at a design stage .................................43
 

3.2.2	 Fire safety objectives competing with "chronic" objectives established after the design stage ........................44
 

3.2.3	 Fire safety objectives competing with "chronic" objectives evolving over very long period of time...............45
 

3.2.4	 Fire safety objectives competing with "chronic" objectives evolving over short or long periods of time ........46
 

3.2.5	 Impact of "chronic" objectives in performing the risk analysis related to disruptive events ............................48
 

3.3	 Theoretical treatment of disruptive events affecting the performance of "building-occupant" systems ...........50
 

3.3.1	 Fire is one disruptive event among others which may be "covered" by a contingency plan.............................50
 

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3.3.2	 PBFPD processes must examine the actions and events of the recovery phase following a fire ......................50
 

3.3.3	 Specific interconnections may exist between different types of targets or between a target and a building
 

component, so a fire can have a direct or an indirect impact on targets............................................................51
 

3.4	 Practical treatment of disruptive events affecting the performance of "building-occupant" systems ...............52
 

3.5	 Conclusions of this chapter...............................................................................................................................55
 

4.	 A Framework For Risk-Informed Performance-Based Fire Protection Design For The Built Environment....57
 

4.1	 Challenges of the current PBFPD processes: the need to be more specific ......................................................58
 

4.2	 Shifting the paradigm: studying how a global system formed by a building and its occupants reacts when a
 

fire can occur ....................................................................................................................................................59
 

4.3	 Application of the system performance-based process to fire disruptive events: Creating a new PBFPD 

process ..............................................................................................................................................................61
 

4.3.1	 The new PBPFD process is a target oriented process within the "building-occupant" system paradigm .........62
 

4.3.2	 Comparison with the current PBFPD processes ...............................................................................................64
 

4.4	 Proof of concept of the New PBFPD process: closing "Iteration Zero" (verification of the usability of the
 

process).............................................................................................................................................................67
 

4.5	 Closing "Iteration Zero" (demonstration of the ability to overcome the challenges encountered by the use of
 

the current PBFPD processes)...........................................................................................................................71
 

4.5.1	 Risk acceptance characterization ......................................................................................................................71
 

4.5.2	 Target vulnerability criteria estimation.............................................................................................................72
 

4.5.3	 Fire risk analysis (quantification of the likelihood) ..........................................................................................73
 

4.5.4	 Fire risk analysis (quantification of the impact) ...............................................................................................76
 

4.5.4.1 Quantification of impact vs. quantification of consequences ........................................................................76
 

4.5.4.2 Tools and data needed for the quantification of the impact of fire events.....................................................76
 

4.5.5	 Integration of the fire protection measures into the "building-occupant" system .............................................77
 

4.5.6	 Cost-Benefit analysis of the fire protection measures.......................................................................................79
 

4.6	 Conclusions for this chapter..............................................................................................................................80
 

5.	 Establishing a plan of action for the development of guidelines in support of the framework for risk-informed
 

performance-based fire protection design.........................................................................................................82
 

5.1	 The need for an iterative plan of action ............................................................................................................83
 

5.2	 Importance of the involvement of the stakeholders for establishing validation domain of models needed at 

each step of the PBFPD process .......................................................................................................................87
 

5.3	 Application of the plan of action to obtain the necessary guidelines to perform each step of the new PBFPD
 

process ..............................................................................................................................................................88
 

5.3.1	 Proposed path of action to quantify Step 1: risk characterization .....................................................................88
 

5.3.1.1 Description of the risk characterization step and corresponding path of action ............................................88
 

5.3.1.2 Research to be carried out for "Risk characterization" Step..........................................................................89
 

5.3.1.3 Establishing guidelines or standards for assessing risk characterization for "building-occupant" systems ..93
 

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5.3.1.4 Using the guidelines for performing Step 1 in a PBFPD process..................................................................94
 

5.3.2 Proposed path to quantify Step 2: Target vulnerability criteria estimation .......................................................94
 

5.3.2.1	 Description of the target vulnerability criteria estimation step and corresponding path of action ................94
 

5.3.2.2	 Research to be carried out for estimating vulnerability criteria.....................................................................95
 

5.3.2.3	 Establishing guidelines or standards for assessing vulnerability criteria of human/equipment/structures in
 

case of fire events..........................................................................................................................................96
 

5.3.2.4	 Using the guidelines for performing Step 2 in a PBFPD process..................................................................96
 

5.3.3 Proposed path to quantify Step 3: Fire risk analysis (quantification of the likelihood) ....................................96
 

5.3.3.1	 Description of the fire risk analysis (quantification of the likelihood) step and corresponding path of action . 

.......................................................................................................................................................................96
 

5.3.3.2	 Research to be carried out for the process step related to the quantification of the likelihood of fire events 98
 

5.3.3.3	 Establishing guidelines or standards for assessing the quantification of the likelihood of fire events ..........99
 

5.3.3.4	 Using the guidelines for performing Step 3 in a PBFPD process................................................................100
 

5.3.4 Proposed path to quantify Step 4: Fire risk analysis (quantification of the impacts) ......................................100
 

5.3.4.1	 Description of the fire risk analysis (quantification of the impacts) step and corresponding path of action ..... 

.....................................................................................................................................................................100
 

5.3.4.2	 Research to be carried out for the process step related to the quantification of fire events consequences ..101
 

5.3.4.3	 Establishing guidelines or standards for assessing the quantification of fire event consequences ..............102
 

5.3.4.4	 Using the guidelines for performing Step 4 in a PBFPD process................................................................102
 

5.3.5 Proposed path to quantify Step 5: Evaluation of the integration of the fire protection measures in the system 

........................................................................................................................................................................102
 

5.3.5.1	 Description of the step relative to the evaluation of the integration of the fire protection measures in the
 

system and corresponding path of action ....................................................................................................102
 

5.3.5.2	 Research to be carried out for the process step related to the evaluation of the integration of the fire 

protection measures in the system...............................................................................................................104
 

5.3.5.3	 Establishing guidelines or standards for assessing the integration of fire protection measures in a considered
 

"building-occupant" system.........................................................................................................................105
 

5.3.5.4	 Using the guidelines for performing Step 5 in a PBFPD process................................................................105
 

5.3.6 Proposed path to quantify Step 6: cost benefit analysis ..................................................................................105
 

5.3.6.1	 Description of the cost-benefit analysis step and corresponding path of action ..........................................105
 

5.3.6.2	 Research to be carried out for the process step related to fire protection measures cost benefit analysis ...106
 

5.3.6.3	 Establishing guidelines or standards for fire protection measures cost benefit analysis .............................106
 

5.3.6.4	 Using the guidelines for performing Step 6 in a PBFPD process................................................................106
 

5.4 Conclusions for this chapter............................................................................................................................107
 

6. Conclusions: main outcomes ..........................................................................................................................109
 

7. Future work.....................................................................................................................................................112
 

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LIST OF FIGURES
 

Fig. 2-1. Barajas terminal 4 panorama, Madrid........................................................................................................20 

Fig. 2-2. Level of Fire Safety and the reduction due to the different processes [50]................................................22 

Fig. 3-1. Examples of facilities under the ICC IBC Institutional class (I2)..............................................................36 

Fig. 3-2. People description according different functional zones of a hospital.......................................................38 

Fig. 3-3. "Disruptive event" profile of the Philips Plant fire (Albuquerque, New Mexico, USA), March 17, 2000, 

adapted from [7] ........................................................................................................................................41 

Fig. 3-4. Examples of airport architectural designs..................................................................................................44 

Fig. 3-5. Examples of impacts of the security "chronic" condition in airports.........................................................45 

Fig. 3-6. Examples of a) well lit facility ("Nightingale" ward), b) private patient room in a hospital .....................46 

Fig. 3-7. Christmas tree located close to exit routes and main entrance of a shopping mall ....................................47 

Fig. 3-8. Example of commitment in a Japanese game center .................................................................................49 

Fig. 3-9. Example of a French department store display during sales ......................................................................49 

Fig. 3-10. Political and technical steps of the system specific risk-informed performance-based process ................52
 

Fig. 3-11. Practical treatment of multiple disruptive events.......................................................................................54
 

Fig. 4-1. Fire exit way finding problematic in a conference center..........................................................................60
 

Fig. 4-2. Application of the system performance-based process to a fire disruptive event ......................................62
 

Fig. 4-3. Steps to be performed in the technical aspect of the proposed PBFPD process ........................................64
 

Fig. 4-4. Relative influence of the stakeholders and the fire protection engineer in the different steps of the
 

elaboration of the design brief according to SFPE guide [5] .....................................................................65 

Fig. 4-5. Comparison between the new PBFPD process and the PBFPD process established by SFPE [5] ............66 

Fig. 4-6. Translation of fire risk characterization in the "building-occupant" system paradigm..............................68 

Fig. 4-7. Translation of the performance requirements of the "building-occupant" system as fire risk 

characterization..........................................................................................................................................69
 

Fig. 4-8. Schematic representation of the risk reduction of scenarios of disruptive events......................................70
 

Fig. 4-9. Concept differences between the FPE current paradigm and the "building-occupant" system paradigm..74
 

Fig. 4-10. Indirect effects of a fire upon the overall "building-occupant" system performance.................................74
 

Fig. 4-11. Blocked opened doors in a vestibule separating hotel room corridor from a stairwell in a hotel ..............79
 

Fig. 5-1. Plan of action: "climbing the research to application/regulatory ladder"...................................................83
 

Fig. 5-2. Influence of stakeholders’ input on the PBFPD process............................................................................84
 

Fig. 5-3. Interconnections between the step researches of the proposed PBFPD process ........................................86
 

Fig. 5-4. Proposed path to risk acceptance characterization.....................................................................................89
 

Fig. 5-5. Example of fire risk curves for commercial buildings [14] .......................................................................91
 

Fig. 5-6. Death risk trends in Japanese residential buildings, hospitals and hotels between 1969 and 2000 [15] ....91
 

Fig. 5-7. Correlation between Fatalities in Hospital and Number of Beds [15] .......................................................92
 

Fig. 5-8. Proposed path to target vulnerability criteria estimation ...........................................................................95
 

Fig. 5-9. Proposed path to the quantification of the likelihood of fire events ..........................................................98
 

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Fig. 5-10. Proposed path to the quantification of the impacts of fire events ............................................................101
 

Fig. 5-11. Levels of fire safety as a function of building phases and the introduction of redundant fire protection
 

measures, adapted from [27]....................................................................................................................103
 

Fig. 5-12. Proposed path to the Evaluation of the integration of the fire protection measures in the system...........104
 

Fig. 5-13. Proposed path to the cost-benefit analysis of the trial designs.................................................................106
 

Fig. 7-1. Interconnections between tools, input data and 'test bed' environments ..................................................112
 

Fig. 7-2. Occupant populations as a function of buildings .....................................................................................113
 

Fig. 7-3. Fire distributions as a function of buildings.............................................................................................114
 

Fig. 7-4. Effects of fire distributions on building occupant populations ................................................................114
 

Fig. 7-5. Validation domains for different "building-occupant" systems, in comparison with the physical domain
 

of possibilities involving buildings, fires and occupants .........................................................................115
 

LIST OF TABLES 

Table 2-1. Performance criteria gathered in codes, standards and guides and guidelines [4]......................................13
 

Table 5-1. Calculations conditions for example risk curves [14] ................................................................................90
 

Table 5-2. Transition of Requirement for Sprinkler Installation of Hospital (Fire Code in Japan) [15] .....................92
 

Table 5-3. Structure Fires in Health Care Facilities, Excluding Nursing Homes by Extent of Flame Damage [8].....99
 

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1. INTRODUCTION 

1.1 Context of the research 

Fire safety issues have to be considered for the built environment, as fire is one of the technological hazards of 

concern. Regulations regarding fire safety have been implemented for centuries, most often with new 

requirements developed mainly after disasters. 

Fire safety regulations are typically implemented via "building codes" and "fire codes," which in turn rely on 

reference standards and guides for deeper technical aspects. For example, in the USA, a state might promulgate 

a building code based on the International Building Code [1], a model building code developed by the 

International Code Council. The IBC in turn requires the installation of sprinklers in particular types or classes 

of buildings. The technical specification of the sprinkler system design is referenced to a design and installation 

standard published by the National Fire Protection Association [2]. In the USA system, the requirements in the 

building code and reference standards are highly prescriptive. 

The concept of performance-based design (PBD) for fire protection emerged in the 1970s in the USA in order to 

consider alternatives to the prescriptive design with the objective to obtain a built environment at least as safe as 

the one that would have been designed according to the regulation. This concept emerged in other countries, 

such as England and Australia in the 1980s and 1990s as fire safety engineering (FSE). 

PBD has been used in cases where the involved stakeholders (mainly the building owner and the architects) 

wanted to design a building that was "outside of the box". Unique buildings such as skyscrapers, buildings with 

inner large open spaces (atria), complex built environments such as subway transit stations or airport terminals 

and even buildings inside buildings are the best candidates for the use of PBD, as prescriptive regulations have 

a difficult task to consider generic solutions to such particular buildings. 

While national building codes are primarily concerned with the safety of the building occupants, with some 

variations to include the neighboring people and outside personnel operating during emergency situations, PDB 

solutions may also incorporate objectives that are not life-safety related such as business continuity, property 

protection, environment protection, and heritage preservation. 

It should be noted that the engineering process of PBD is currently aimed at comparing the final engineering 

design with the one elaborated from the prescriptive regulation within a particular jurisdiction, as the final 

design would have an equivalent level of safety to that provided by the "prescriptive" solution. Because non 

life-safety objectives may not be fully addressed in local building codes, authorities having jurisdiction may 

accept the PBD solution that they judge acceptable while not adequate to fulfill objectives such as property 

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protection. In other terms, as authorities having jurisdiction are used to judging prescriptive solutions aimed at 

life safety objectives, the PBD solutions they deem acceptable may not address non life safety objectives that 

could be of a major concern for other building stakeholders. 

Several countries around the world have integrated performance-based elements into their regulations at two 

fundamental levels: 

- at a technical level, as fire protection engineering still requires significant research in order to describe and 

model all the different phenomena; 

- at a political level, as PBD is part of a decision-making process involving stakeholders' risk acceptance, 

determined at a national level with regulations and at a local level when the authorities having jurisdiction 

judge the PBD report acceptable or not, based on their own risk acceptance/aversion level. 

A building project implies the participation of different groups of stakeholders, including contractors, building 

owners and users, architects, mechanical engineers, fire protection engineers and the authority having 

jurisdiction which approves the construction and the use of the project. These groups are involved at different 

stages of the project and undertake different tasks and mandates. So, each of these groups defines the 

performance of the project according to their mandates that run for a limited time or expand to the overall 

lifespan of the building. The overall performance of a building depends on the interrelations between the 

different components of the building such as the architectural system, the climate system, and components used 

for emergency situations, many of these components are separately managed by specific engineers. 

1.2 Organization of the dissertation 

The dissertation is organized into seven chapters as follows: 

Chapter 1 (this Introduction) provides some background and context to the Ph.D. research. 

Chapter 2 presents the results of a review of two decades of worldwide experience using standards, codes and 

guidelines related to performance-based fire protection design for buildings, in terms of challenges and 

shortcomings resulting from the application of these documents. Two key outcomes of this review are that (1) 

several of the challenges which have been identified are strongly linked to the application of generic guidance 

to specific problems, which results in critical details being missed, and that (2) some of the engineering issues 

are treated within a political context, while they should be addressed as purely technical issues. 

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Chapter 2 served as the basis of a paper that was submitted to the Journal of Fire Protection Engineering 

(submitted 12 August 2012, with the manuscript number JFE-12-0035), which was under review when this 

dissertation was published. 

Chapter 3 presents a new study paradigm organized around systems formed by specific building types, the 

activities being undertaken in the buildings, and the building occupants that I define as "building-occupant" 

systems. It focuses on how events such as fires or any other emergency situations can affect the overall 

performance of these systems. A system specific risk-informed performance-based process is established in 

order to assess the effect of a single or multiple disruptive effects of any type on the overall performance of the 

system. 

Chapter 3 served as the basis of a paper that was submitted to the journal Building and Environment (submitted 

29 November 2012, with the manuscript number BAE-D-12-01181) and was under review when this 

dissertation was published. 

Chapter 4 presents the application of the aforementioned process to fires as they constitute one of the main 

disruptive events that can affect the overall performance of a "building-occupant" system. This chapter focuses 

on how a successful implementation of the corresponding new risk-informed PBFPD approach will require 

acceptance of the need for a paradigm shift from one in which fire is the center of the problem to one in which 

building performance metrics are evaluated in case of fire events. This chapter also details the different steps of 

the new PBFPD process and how this process differs from the current ones, notably in separating technical steps 

from political steps related to decision making and policy. Finally, this chapter presents how the process is 

practically applied to a project and it focuses on a proof of concept of the new PBFPD process. 

Chapter 4 served as the basis of a paper that was submitted to Fire Safety Journal (submitted 3 December 2012, 

with the manuscript number FISJ-D-12-00256) and was under review when this dissertation was published. 

Chapter 5 presents an iterative plan of action related to the establishment of the guidelines required to perform 

each of the technical steps of the process presented in the previous chapter for fire disruptive events. It provides 

elements of research currently available in the technical literature and how these elements could be incorporated 

into future guidelines. It also emphasizes on the importance of the involvement of the stakeholders for 

establishing the validation domain of models needed at each step of the PBFPD process. 

Chapter 6 summarizes the main outcomes of this PhD research study. 

Chapter 7 briefly introduces future work and how this plan could be practically facilitated via a web-platform as 

a collaborative environment. 

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A total of three appendices (A1 to A3) are provided at the end of this document as supplementary material. 

Appendix A1 is a paper titled "Towards an Integrated Performance-Based Design Approach for Life Safety 

Across Different Building Use Groups" which was presented at the international conference "Interflam 2010". 

This paper stated the advantages and drawbacks of using fire incident databases and fire investigation reports as 

information for selecting and quantifying fire scenarios. It also indicated the relevance of other sources such as 

building and fire codes, agency- or occupancy- specific guidance. This paper also showed the limitations of 

generic methods used to treat this information and that established in current Performance-Based Fire Protection 

Design (PBFPD) guidelines, based on the differences between configurations found in assemblies, offices, 

hospitals and so forth, which make it difficult, if not impossible to develop detailed guidelines without dealing 

with the elements that make a building occupancy specific. It also replaced fires as one of the "perturbations" 

occurring in buildings, which specific types had specific "chronic" or everyday demands. 

Appendix A2 is a paper titled "“Ready-to-Use” Building Layouts and Combustible Packages for 3-D Fire 

Simulations" which was presented at the Fire and Evacuation Modeling Technical Conference 2011. This paper 

first introduced the concept of 'test bed' studies related to the use of fire effects tools for given applications, with 

an emphasis on the fire Computational Fluid Dynamics model FDS (Fire Dynamics Simulator) developed by 

US National Institute of Standards and Technology. It also proposed to establish databases gathering together 

already constructed 3-D building layouts, fire and combustible packages containing information on heat release 

rates and fire effluent productions that fire protection engineers or researchers could easily use. 

Appendix A3 is a paper titled "'Test bed' environment process for assessing the appropriateness of engineering 

tools to be used in performance-based design applications," published in the Proceedings of the 9th International 

Conference on Performance-Based Codes and Fire Safety Design Methods. This paper extended the concept of 

'test bed' studies to all the engineering tools as it developed a new holistic approach for selecting tools to be 

used in performance-based fire protection design applications, at a technical level due to the complexity of the 

tools involved (fire effects tools, evacuation tools, structural response tools) and at a user level due to the facts 

that tools are used in a specific context, where input data may not be available as needed, analytical methods 

from already existing standards may be preferred to more sophisticated engineering methods based on their 

better acceptance by the authority having jurisdiction. 

References 

1. International Code Council (2012), International Building Code, 2012 edition, International Code Council 

2. NFPA (2010), NFPA 13 "Standard for the Installation of Sprinkler Systems" 

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2.	 TWENTY YEARS OF PERFORMANCE-BASED FIRE PROTECTION DESIGN: 

CHALLENGES FACED AND A LOOK AHEAD 

In recent decades, more and more building regulatory systems around the world have permitted or required a 

performance-based approach to fire protection design instead of requiring that code prescriptions be followed 

[1,2]. This option was interesting to the market because it enabled innovation, aesthetics and optimization of 

usable space, while maintaining an acceptable level of safety [3]. In addition, this option also added more 

emphasis on safety objectives other than ones related to life safety such as property protection, business 

continuity, environmental protection and historical preservation. From an engineering perspective, the 

performance-based fire protection design framework is valuable as it integrates scientific knowledge into the 

design process so that fire protection engineers (FPEs) can do more than rely on code prescriptions that are 

usually implemented as a political response, after major accidents, of code enforcers and Authorities Having 

Jurisdiction (AHJ). Besides, using a variety of tools as a support, the analysis should bring more engineering 

rigor and "furthermore, performance-based design should result in a comprehensive fire protection strategy in 

which all systems are integrated, rather than designed in isolation" [4]. 

Basically, the current approach to Performance-Based Fire Protection Design (PBFPD) can be divided into the 

following three major steps (as reflected in such guidance such as BSI [5], ISO [6],IFEG [7] and SFPE [8]): 

1) Stakeholders establish goals and objectives, which are then translated by fire protection engineers into 

design objectives and performance criteria. Then, stakeholders agree on fire design scenarios upon which 

trial designs, elaborated by the FPEs, are evaluated. This part of the process is documented in the Fire 

Engineering Brief (FEB); 

2) The FPE evaluates the consequences of the selected fire design scenarios and compares their outcomes with 

the selected performance criteria. In order to do so, he/she uses appropriate tools to evaluate the 

development of the fire (fire effects tools), the evacuation of the building occupants, and the response of the 

structure (and the building contents and systems) to the fire design scenarios; 

3) The FPE elaborates trial designs that pass the performance criteria, the stakeholders decide which one to 

finally retain for the considered project and the FPE writes the related documentation in terms of 

specification, operation, and maintenance of the fire protection measures. 

The current approach relies on guidelines and standards which are rather generic in nature, process-oriented 

documents, which do not specify critical components such as performance (design) criteria, fire scenarios, 

quantified design fires, and required means of design evaluation/verification. All of these decisions are left to 

the FPE working in concert with project-specific stakeholders. This has led to a wide variation in designs and 

levels of delivered performance. In 2007, examining the New-Zealand perspective, Wade et al. [11] identified 

that a "perceived deficiency in the [fire engineering practice was] the lack of clear guidance from the regulator 

for performance criteria and design fire characteristics and scenarios for use in performance-based design. This 

[meant it was] difficult to achieve a uniform approach and consistent safety level through the country". 

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Nonetheless, based on the large number of performance-based design projects which have been showcased in 

the literature over the past 20 years, it seems clear that this process has been accepted by AHJs and the other 

stakeholders involved in the project, that is to say, building owners, designers, reviewers, enforcers, insurers, 

contractors and the Fire Services. Examples of these projects include a unique hotel and Casino complex [12], a 

complex rental car facility integrated in an international airport [13], extension of an existing airport [14], and 

numerous high-rise buildings [15,16]. However, I have not learned as much as I might have from these since the 

level of detail in published summaries is sometimes light, full PBFPD reports are often client confidential, not 

all jurisdictions may make all design documentation available, and few comparative reviews have been 

undertaken. 

Reviews of performance-based codes (e.g., building codes in Australia, New Zealand, England and others), 

performance-based design processes (like the one elaborated in the SFPE PBD Guide or actual PB design 

solution), and codes that allow a performance-based design option (e.g., NFPA 5000 [17]) can be found in the 

technical literature ([18,19]). Nevertheless, many deal only with the global comprehension of the PBD process 

and possible ways to cope with generic technical issues and better interconnection between FPEs, "lawmakers 

and people making standards" [20]. In applying the Fire Engineering Brief process, Schulz and Feeney [21] 

found shortcomings in the process, particularly when stakeholders are risk averse and unfamiliar with new 

design methods, which would lead to a higher (and more or less variable) amount of justifications needed for 

the "selection of input parameters and relevant design scenarios". It should be noted that they also plead for 

incorporating flexibility as "design and preferences for different solutions change over the course of the project 

[...] which will invoke the need for specific discussion with various stakeholders (especially those involved in 

the regulatory approval)". 

In the USA, there is no centralized mechanism for consolidating feedback regarding how the PBFPD process is 

handled from a regulatory perspective, so comparative reviews are lacking. There are several reasons for this: 

- The building regulatory system in the USA is managed by the states – there is no federal government 

mandate and therefore no centralized systems for building regulation at the federal level. 

- There is no standardized mandatory system for review and acceptance of PBFPD at a state or local level. 

Acceptance of PBFPD projects therefore varies widely across cities, counties and US states. 

- AHJs may have considered that each PBFPD project was unique in terms of key fire engineering 

components (e.g., quantification of performance criteria, selection of fire design scenarios, implementation 

of fire protection measures), so no reason was seen for collecting and compiling the specifics of each 

project. 

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Also, while there is PBFPD in the USA, the USA has not embraced performance-based building codes. In 2008, 

Tubbs and Okawa [18] examined why the International Code Council (ICC) Performance Code (PC) has not 

been widely adopted since its first publication in 2001. They noted that one barrier to that adoption or to the 

general adoption of the PBFPD option in the USA in general, was related to the use of computational tools and 

to data availability: even though they recognized that advancements had been realized in computational fluid 

dynamics (CFD) based fire effects models as well as with egress models, they noted that challenges still existed: 

"all models of course have their limitations but if well documented and understood by the designer[, they] can 

be excellent design tools. The aspect that is most crucial to their use is the appropriate inputs. [...] This 

continues to be one of the largest barriers to wide spread implementation of performance based codes and 

design". This barrier is related to the technical aspect of the application of PBFPD, notably linked to the use of 

tools (model limitation and validity) and data availability. Tubbs and Okawa also found a barrier related to the 

approval process: the "uncertainty when applying the code in terms of qualifications and related process issues" 

made the AHJ "very wary of reviewing and approving PB designs especially those that are well beyond the 

basic code requirements". In other terms, when accepting a PBFPD instead of prescriptive requirements, the 

AHJ liability was extended further than when simply verifying that the code provisions have been followed, 

even if the AHJ could still rely on a peer reviewer. 

Thus, 20 years of experience of using guidelines that are too generic in nature has resulted in considerable 

variability in the application and in the acceptance of the PBFPD option. Because of the generic nature of the 

guidelines, the selection of acceptance criteria and fire designs is more a ‘collegial political’ choice than an 

outcome of a real characterization and treatment of the fire risk in the building. Theoretically this means that 

within the same community, three different engineering firms can develop three different designs for the same 

building project, each of which results in different levels of risk in terms of occupants, property and mission. 

Furthermore, simply by moving the building location to another community, the same designs could be 

accepted or rejected based solely on the perspectives of the different stakeholders involved. To address these 

issues, FPEs need a more robust framework, with a clear and explicit process to help characterize the life safety 

risk, the property risk and the business risk, which will result in buildings with more equivalent levels of safety. 

2.1 Technical and political challenges related to the use of PBFPD processes 

Across the world, attempts have been made to address this need, within the regulated structure of national codes 

and standards and using different approaches, but they all seemed to have failed in one way or another, in part 

because of the challenges posed by the applicability of generic approaches. The challenge of being too generic 

applies to the technical aspect of the engineering method, as well as the decision making process embedded in 

the application of the approach itself, which is referred in this dissertation as the political aspect of the PBFPD 

process. As mentioned by Brannigan et al. [22] as early as 1996, "technological and policy issues raise 

fundamentally different kinds of questions: 

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- Technical decisions are those which deal with scientific or technological phenomenon that are the subject 

of well-defined scientific or technical decision processes. 

- [Political or] Policy decisions are those which involve weighing of competing social, legal, cultural, 

technical and other judgmental factors in the regulatory process". 

The main technical and political challenges related to the use of PBFPD are presented as follows. 

2.1.1 Technical challenges related to the use of PBFPD processes 

Decades ago, when the PBFPD concept was introduced into national regulations, fire protection engineering 

was still in its "infancy stage" [2]. As a result, efforts were primarily undertaken to increase the global 

knowledge related to the consequences of a fire in a building. Some advances were also made in describing 

human behavior during the evacuation process [23,24], and fire loads were added to the more well established 

formulas for the resistance of structures [25]. In addition, SFPE [26] indicated that research related to the use of 

PBFPD process had to be undertaken in order to address uncertainties in the following areas: 

- Knowledge relating to the science and engineering being used, due to limitations on the amount of 

knowledge available for used in models, 

- Human behavior, related to "unknowns with regard to the exact behavior of people", 

- Risk perception, attitudes and values, as it is "difficult to capture all societal views when undertaking a 

project". 

In order to address these uncertainties, research was undertaken regarding the technical aspect of the PBFPD 

process. However, it was not addressed in the definition of the PBFPD process itself, in particular in its political 

aspect, which links the engineering analysis results with the policy decision making process. For example, in 

1997, Richardson et al. [27] already listed technologies required for PBFPD. Their list included extended 

examples of technologies to assess combustibility of construction materials, fire growth, smoke spread, fire 

resistance of compartmentation and structural assemblies, occupant evacuation and to lesser extent examples of 

technologies related to fire risk assessment and fire cost calculations. By looking at the technical literature, it 

can be seen as a plethora of elements that contribute to the reduction of uncertainties in the technical aspect of 

the PBD process, but there are a lot less regulatory details which interface the political aspect of PBD with the 

technical aspect. 

2.1.2 Political challenges related to the use of PBFPD processes 

Since different levels of performance are achieved at different costs, political decisions of the PBFPD process 

can supersede technical decisions. As used here, political decisions refer to those made by stakeholders, which 

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can include government (at all levels), clients, and others. For example, in some situations the cost of installing 

and maintaining a sprinkler system could exceed its benefits in terms of the property remaining undamaged by a 

fire. For some stakeholders, this technical solution, which leads to a technically-acceptable fire safety design, 

may not be politically considered because of its cost. Charters and Ramachandran [28] illustrated this point with 

a PBFPD study that demonstrated business continuity and property protection benefits to an operator of bus 

garages in the UK if installing sprinkler systems in these facilities. "However, the cost-benefit analysis and the 

operator’s contingency plans meant that there was no cost-benefit or consequence case for installing sprinkler 

[in] the bus garage. As a result of the risk assessment, the operator did implement other forms of safeguard and 

fire precaution". 

In some cases, it is possible to compare the cost-benefit ratio of two different fire protection design options, 

particularly when they are both technically viable (sprinkler vs. fire rating barriers), but it can be quite difficult 

to assess the relative costs and benefits of a technical fire protection measure as compared with a managerial 

fire prevention measure (e.g. management of fire loads and ignition sources). In the case of nightclubs, 

managerial procedures such as allowing more people than the prescriptive limit in conjunction with the use of 

fireworks in an environment with flammable linings and ceiling have repeatedly led to fire disasters (Lame 

Horse Club, December 5, 2009 - Santika Pub, January 1, 2009 - Wuwang Club, September 21, 2008 – 

República Cromañón, December 30, 2004 - Station nightclub, 2003). One might ask what the costs of having 

strict managerial procedures which would have prevented the over capacity of the nightclubs and elements that 

led to a very fast spreading fire would have been as compared to the costs and the benefits of sprinklers. The 

implementation of managerial procedures in preventing the start or mitigating the consequences of a fire also 

raises the issue of their enforcement and their real efficiency or contribution in a benefit-cost analysis. 

More detailed discussion of the analysis of the current PBFPD processes is presented as follows, in terms of 

challenges that these current processes have to overcome in order to ultimately establish guidelines that would 

be more complete to follow through for the fire protection engineer and easier to verify for the authorities 

having jurisdiction. 

2.2 Detailed challenges of current PBFPD processes 

From the time PBFPD processes were elaborated to their current applications in at least 15 countries, 

practitioners, code enforcers and researchers have shared their experience, in technical publications and during 

conferences. They discussed on the advantages and drawbacks of applying and accepting PBFPD processes by 

identifying critical issues related, not only to the use of a particular process, but also to the definition of the 

steps of the process itself and to the interactions between the technical aspect and the political aspect of such 

processes. Before describing these issues in detail, consider the following examples of concerns, expressed 

across almost the last two decades. 

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In 1992, Grubits [29] suggested that a "performance building code must: 

- Set out the process to be adopted, 

- Provide the factors to be considered in design, 

- Specify the performance levels to be attained, 

- Adopt explicit safety margins, 

- Specify what relevant data sources are acceptable". 

Ten years later, Johnson [19] indicated that "many of [the challenges related to the use of PBFPD were] more in 

the policy, regulatory, approval and accreditation area, rather than in the science and technology field, although 

clearly traditional fire research is still needed, especially in the area on safety factors and uncertainty". He 

discussed some of the challenges, which concerned the Australian PBFPD process or the generic application of 

PBFPD: 

- What should the extent be to which property protection be regulated on behalf of the community (which is 

concerned by sustainability, job protection, environmental protection) or on behalf of the building owners and 

insurers? 

- Fire fighters protection is addressed but application of performance criteria for building occupants does not 

seem to fit for these trained and better fit people. No guidance is given to get approved performance criteria 

for fire fighters. 

- The concept of risk does not appear to be acknowledged by the regulators, which can lead the fire protection 

engineer to be legally exposed in case of a rare catastrophic event even though the building design seemed 

robust and appropriate to all the involved stakeholders. "It is essential that building codes and legislation 

recognize the balance of risk and cost. A key factor is the completion, validation and greater use of risk-cost 

models to 'measure' and agree levels of risk and acknowledge this in our regulatory frameworks". 

- Certification, accreditation and fees of people involved in the performance-based fire protection design, as 

well as the independence of the peer reviewers and consistency of the approval process are still in discussion. 

- Maintenance of the fire protection measures and change in the use of the building are linked to the issues of 

enforcement and approval of changes. 

- Data "for input to [PBFPD] methods and models continues to be a limitation requiring conservative design". 

- "The degree to which building codes are open and closed to internationally accepted standards, products and 

technologies is becoming a major challenge to international trade". 

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He concluded that "these challenges need[ed] continuing research, debate and consultation across all sectors of 

this industry, and leadership both nationally and internationally. [...] In particular the need to improve 

administrative and regulatory processes [were] probably even more important than further development of the 

science and technology". 

Also in 2002, Barber and Merkestein [30] also explored the "issue of inconsistency in the approvals process and 

the reasons behind the difficulties in achieving a transparent design resolution, for PB fire engineering". They 

referred to Meacham [1] who had "recognized the need for peer review and a high degree of education for both 

AHJ's and fire engineers". They also concluded that "a formal level of training, communication, forums and 

more education in performance based design and fire science for AHJ's and fire engineers is required.[...] The 

fire engineering community as a whole (fire engineers and AHJ's) should be working to achieve a globally 

recognized process of approvals". 

More recently, in 2008, Johnson et al. [31] indicated that "in fire engineering for the built environment the 

process of hazard analysis, development of fire scenarios and choice of design fires for fire engineering 

calculations are the most problematic". 

These examples show multiple challenges in the application of PBFPD processes, at a technical level and at a 

political level. The following paragraphs discuss the key challenges which have been identified in more detail. 

2.2.1 Challenges when applying generic guidance to specific projects 

To date, codes, standards, guides and guidelines related to PBFPD have been written in order to be used for any 

type of built environment and project. Paradoxically, this generic applicability has made the guidelines 

ineffective in helping engineers thoroughly apply the PBFPD process for a particular project. Parameters to be 

considered in the PBFPD process are presented, but even if their influences within the overall analysis may 

seem obvious to a trained FPE, they may not be for the stakeholders. In addition, the way parameters are 

introduced in the generic PBFPD processes can be confusing even for the FPE. For example, in the SFPE 

engineering guide to PBFPD [8], information related to the building and its occupants, needed for the analysis is 

only presented in its Chapter 8, as it should be considered for characterizing design fire scenarios. Numerous 

building items, including building services and processes, operational characteristics, environmental factors, as 

well as occupant items are cited in this chapter but their uses within the PBFPD process are not explicitly 

indicated in the rest of the engineering guide. Neither their metrics (for example, how is the "social affiliation" 

item supposed to be considered as a parameter of egress models?) nor influences on the overall analysis are 

indicated. It should be noted that this guide indicates in its Section 6.2.2 that "the process of developing 

quantifiable design objectives should focus on target(s)", but that focus is totally absent in the subsequent 

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chapters dealing with the development of design fire scenarios. By this, SFPE [8] defines targets are as 

"building, compartment, process, or occupant that is protected in order to meet a specific stakeholder objective". 

A similar observation can be made with respect to the International Fire Engineering Guidelines (IFEG) [7]. 

The principal building characteristics (1.2.3 of IFEG) are listed upfront because "in order to evaluate or design a 

building's fire safety system, it is important to understand the building's characteristics and its normal mode of 

functioning. The principal characteristics should be identified early in the FEB process in order to facilitate the 

decisions that need to be made and issues to be resolved". Dominant occupant characteristics are listed in the 

following section (1.2.4 of IFEG), as they "should be considered in identifying the design occupant groups for 

the building [...] explained in Section 1.2.12 of these Guidelines", which states that "if any occupant groups 

have characteristics which would influence the outcome of a fire scenario, they should be considered for 

identification as a design occupant group. In some cases, the design occupant group may consist of only one 

person". The IFEG provide an example of design occupant groups for hospitals: staff defines the detection time 

and the pre-movement time while movement times would be defined by the types of patients. In spite of this 

single detailed example, it is unfortunate that the Methodology Part of the IFEG does not go on while 

presenting methods to assess the evacuation process (chapter 2.8 of IFEG) and that the Data Part of the IFEG 

does not include any corresponding data on design occupant groups, or at least help the FPE by providing ways 

to access this data. 

To summarize, PBFPD processes included in codes, standards, guides and guidelines were written at a time 

when it was a priority to introduce the global concepts of the PBFPD process, to model all the phenomena, and 

to determine and assess the influence of critical components of the PBFPD process. With this purpose in mind, 

they had to be generic in order to be used as widely as possible. After decades of application of these processes, 

it seems that this wide applicability turned to be a drawback leading to all the challenges presented as follows. 

For this reason, it appears that the next generation of guidelines will have to include more details and 

specificities of the considered types of projects, to which all the engineering process have to be refocused on. 

2.2.2 Challenges associated with the definition, use and quantification of the performance/acceptance criteria 

Custer and Meacham [4] defined performance criteria (also called acceptance criteria) as "metrics against which 

building materials, assemblies, systems, components, design factors and construction methods will be evaluated 

on their ability to meet specific performance requirements". As early as 1997, they gathered the following 

performance criteria, which are presented in Table 2-1 with their references. The nature of the reference 

indicates the level of regulation (code, standard, guide and guideline). No change occurred between the editions 

of the references examined in Table 2-1 and the current official editions, if still in use. It should be noted that 

some thermal exposure criteria can also be found in standards and regulations used to determine the hazard 

distance to people exposure from a LNG fire, outside a built environment [32]. 

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Acceptance criteria are derived from fire protection goals (life safety, property protection, business 

continuity...): they are highly dependent on the characteristics of the building occupants, contents and structure. 

When looking at the values collected in Table 2-1, these characteristics can be implicit: for example, the criteria 

associated with "level of fire gases" mix the person height (1.6 m component) with the height of the room 

(0.1 H). The criteria related to heat radiation effects on people seem derived from physiological studies and 

translate well the potential damage to building occupants while receiving radiative heat fluxes from a fire. What 

is more disturbing is that the last criterion in Table 2-1 can be found in Section 921.2 of the sixth edition of the 

Massachusetts State Building Code as the design criteria of a smoke control system. In consequence, since the 

performance criteria are a technical transcription of a political agreement, it seems interesting to find the 

rationale behind the selection and the quantification of the published performance criteria. Nevertheless, this 

task is out of the scope of the current dissertation. 

Table 2-1. Performance criteria gathered in codes, standards and guides and guidelines [4] 

Performance Criterion Reference Date 

The deflection of reinforced concrete structural 

members shall not exceed that permitted by 

ACI 318 

The BOCA National Building Code, 

Building Officials and Code 

Administrators, International, County 

Club Hills, IL 

1993 

The level of fire gases shall not be lower than 1.6 

+ (0.1 H) m, where H is the height of the room 

Swedish Board of Building, Housing 

and Planning, Building Regulations, 

Sweden 

1994 

Limiting conditions for tenability caused by heat 

radiation: less than 2.5 kW/m2 can be tolerated for 

over 5 minutes; 2.5 kW/m2 can be tolerated for 

30 seconds; 10 kW/m2 can be tolerated for 

4 seconds 

Fire Engineering Guidelines, Fire Code 

Reform Centre, Limited, Australia 

1996 

The smoke layer interface (shall be maintained) 

above the highest of either: the highest unprotected 

opening to an adjoining space, or 6 feet above the 

floor level of exit access open to the atrium for a 

period of 20 minutes 

The BOCA National Building Code, 

Building Officials and Code 

Administrators, International, County 

Club Hills, IL 

1993 

Deterministic values of performance criteria have been published and some are embedded in regulations (such 

as Sweden, Japan and New Zealand). Even with these quantified performance criteria, there is a lack of 

guidance on how these generic values are to be applied. Custer and Meacham [4] indicated that many countries 

using or developing performance-based codes have not included values for the performance criteria because, 

even if some performance criteria may be applicable to any design situation, the selection of performance 

criteria remains situation-dependent. 

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Furthermore, these performance criteria are not really being used to assess the performance of the building to 

withstand the fire threat; rather, they indicate a technical perception of the potential damage to building 

occupants, contents and main structure. It is proposed that "performance criteria" should be called "fire effect 

criteria", as there is a subsequent layer of analysis needed in order to quantify the actual performance of the 

building. The level of building performance should be quantified by answering questions such as: how many 

casualties or injuries would be caused by year of use of the building? How many days a fire would cause 

business interruption? 

Regarding life safety objectives, the performance criteria seem to be implicitly associated with a "no injuries or 

casualties" performance of the building in case of a fire, at least for building occupants "not intimate with the 

initial fire development" [33]. Fire events produce effluents and heat that can cause these injuries and casualties, 

and FPEs are trained to assess these productions. Nevertheless, in case of a fire or emergency situation in a 

highly populated area (theater, stadium, nightclub...) people could result as casualties, not because of toxic or 

thermal threat but because they stampede and get crushed at some points on the evacuation process. As a recent 

example, a student was crushed to death, two others were in a critical condition and at least six (or eight) other 

people injured after a stampede at a nightclub in Northampton, UK. The club was overcrowded 

(1,300 capacity). It is not clear if a fire alarm went off when people were asked to leave the club to get into their 

buses [34]. This phenomenon should also be included when assessing life safety performance criteria associated 

with fires in buildings. When reviewing different PBFPD processes, a performance criterion associated with a 

crush effect in case of stampede for exits has not been found or mentioned: without such a quantified criterion, 

how would FPEs reconstruct the Brooklyn theater fire which killed 278 people on December 5, 1876, the 

Iroquois theater fire (Chicago), which killed 602 people on December 30, 1903 or more recently the Uphaar 

Cinema fire (Delhi, India) which killed 59 people and seriously injured 103 people on June 13, 1997? 

With respect to fire performance across all types of building structures, the "Eurocodes" [25] provide an 

interesting example of how the fire threat is considered, specifically for structures made of concrete, steel or 

timber. The main idea of these documents is to evaluate the action of a "structural fire design" as one more 

action on the structure, such as actions imposed by natural hazards such as earthquake, wind, and snow. The 

definition and the evaluation of the consequences of the "structural fire design" only concern the structure of the 

building and not its occupants and contents. Nevertheless, Kruppa [35] indicated that the safety of people could 

be considered: 

- During a fire evacuation by estimating if the time before collapse of the structure was less than the time to 

ensure the safety of people (which has to be estimated elsewhere) and 

- After a fire, if the remaining deformation of the building components was less than the maximum allowed 

deformation assessed after the cooling phase. 

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In 1997, using an analogous concept taken from the American Society of Civil Engineers, Lucht [36] proposed 

to introduce a simple state equation where the resistance or "strength" of the building was greater than the sums 

of the applied loads: a smoke load, heat load and carbon monoxide load were added with corresponding safety 

factors and then compared with the combined "resistance" of the fire protection systems and the exit system, 

pondered by their reliability factors. In 1999, Meacham [2] attempted to expand upon this concept, with a 

specific focus on evacuation analysis and associated uncertainties in the process. Concerning the definitions of 

the loads and resistances of the fire threat, Fitzgerald [37] had already established a list of technical differences 

between the building structural system and the "far more complex" building fire safety system, rendering 

unpractical the merging of the two concepts. In 2004, Bukowski [38] considered that "fire [was] an event like 

an earthquake or hurricane, but where these natural events [had] statistical distributions in time (magnitude and 

return frequency), fires [were] unique because nearly all fires start[ed] small and gr[e]w until they r[a]n out of 

fuel or air or [were] extinguished. Large fires [were] generally the results of many things going wrong 

simultaneously, and thus represent[ed] a string of conditional probabilities that [were] not well described in 

normal terms, One suggestion for how to develop design fire specifications specific to a building space to result 

in the same stress on the space ha[d] been proposed but this [did] not address the issue of return frequency". 

After reviewing the pros and cons from the technical literature, I decided that this potential way to include fire 

as an additional load was not the most adequate to deal with building occupant evacuation or protection of 

building contents, in spite of its usefulness to assess structural component response in case of a fire. In 

conclusion, this example shows that it does not seem possible to mix methods of evaluations of performance 

criteria for different objectives. This implies that different objectives (life safety, property damage...) have to be 

assessed according to their corresponding level of performance. 

In addition, for life safety objectives, I consider that the corresponding criteria values should be a consensus of 

engineers, not only dealing with fire protection engineering but also toxicology and psychology. For a 

deterministic point of view, a single value per fire effect criterion could be defined for target types. For a 

probabilistic approach, a distribution should be given. 

To summarize, as it is quantified in the current PBFPD processes, the performance criteria should be called "fire 

effect criteria". The terminology "performance criteria" should describe the actual level of performance 

achieved by the considered project, for each of its safety objectives agreed among its stakeholders. Research to 

attain a consensus for fire effect criteria assessment between the different engineering disciplines should be 

done, not only for building occupants, but also building contents relevant to the stakeholders (i.e. important 

piece of equipment, electronic cabinet used for process safety, priceless artifact) as well as environmental 

ecosystems potentially affected by the fire itself and the chemicals used for its extinguishment. 

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2.2.3 Challenges associated with the selection of fire design scenarios 

SFPE [8] indicates that "in a deterministic analysis, one or more possible fire scenarios can be developed as 

design fire scenarios that are representative of potential worst credible fires in a particular building [...]. The 

central challenge in scenario selection is finding a manageable number of fire scenarios that are sufficiently 

diverse and representative". Unfortunately, this guide, or any other guide, guideline or regulation, does not 

provide the fire protection engineer and the involved stakeholders with detailed explanations on what the 

representativeness of potential worst credible fires in a particular building has to be: 

- "Worst credible fires" seem to imply that fires having developed to quite a large extent while remaining 

credible are the ones to be considered. This denomination is too vague because the intensity of the fires 

necessary to have an effect on targets (building occupants, contents and structures) depends on the nature of 

the targets and on the relative position between the fire and the targets. The ICC Performance Code gives 

different levels of "fire maximal tolerable damage" as a function of the importance of the building [39] but 

it does not provide a method to define scenarios leading to these different damage levels. It should be noted 

that focusing on high intensity fires does not necessary means that less intense fires are "covered" even if 

SFPE also indicates that "finding a representative sample of scenarios ensures that if the design is safe for 

those scenarios, then it should be safe for all scenarios, except those specifically excluded as too 

unrealistically severe or too unlikely to be fair tests of the design". In the nuclear power production field, 

the OECD Committee on the Safety of Nuclear Installations (CSNI) indicates, in one of its own technical 

opinion papers, that "not all large nuclear power plant fires are significant from a public safety point of 

view, nor are all safety significant fires large" [40]. As early as 1999, Brannigan summarized concerns from 

himself and others regarding how design fire scenarios were selected and characterized; Dr Hall from 

NFPA was cited regarding the modeling of fire scenarios with: "If only a few scenarios are modeled 

explicitly, then each one is implicitly required to be representative of a much larger and more varied 

collection of other scenarios. There may be no good evidence to support this" [41]. This cited remark is so 

important that it still written, with no change, in the latest edition of the NFPA Fire Protection Handbook 

[42]. Brannigan also stated that the original meaning of a "scenario" used to "represent a technical 

description of the social expectation of safety" was redefined so "scenarios stopped including the entire 

hazard, and became instead just a specified design fire". Building and occupant characteristics which 

defined the problem boundaries were then relegated to the background as input parameters of fire scenarios 

which became the focus of all the PBFPD process. 

- The context related to the term "manageable" is not defined but Hall and Watts [42] link that term to the 

"computational burden" of assessing the consequences of these scenarios, as well as the "shakiness of the 

available data and a desire to minimize the number of different terms supported by expert judgments". This 

context then implicitly states that in a time limited framework, such as the project consulting environment, 

scenarios would be excluded or “clustered” with other scenarios because of time and resources constraints. 

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NFPA 101 Life Safety Code [33] presents a list of design fire scenarios associated with the life safety of 

building occupants (not related to the fire origin) and a list of scenarios (similar to the NFPA one) is proposed to 

be integrated in the building regulations of New Zealand. It should be noted that the scenarios of the NFPA list 

are qualified as "challenging" and are not necessary the "credible worst case scenarios". Hall [43] explains that 

"excluding reliability issues, the conditions that make a scenario challenging tend to fall into two types: 

- Conditions that lead to a more rapid onset of unacceptable outcomes (such as death) or a more rapid onset 

of fire conditions that are taken as proxies of unacceptable outcomes (such as incapacitation, flashover, or 

structural collapse); 

- Conditions that line up with system limitations, which primarily means uncovered or shielded fire 

locations". 

Concerning the second type of conditions, fire protection systems have different modus operandi. I assume that 

when the PBFPD process is used to evaluate the benefits of changing one fire protection feature (usually a 

prescriptive requirement) by an alternative, scenarios challenging both options should have to be elaborated, 

and the overall analysis would not only have to be based on the damage ratio between the two options but also 

contain the evaluation of the likelihood of these scenarios and of the cost of installing and maintaining the 

different fire protection options. None of this is discussed in the current PBFPD processes I reviewed. 

2.2.4 Challenges when dealing with a priori lists of performance criteria and design fire scenarios 

In the current PBFPD processes, the fire design scenarios and the criteria are selected and agreed upon among 

the involved stakeholders prior to any development of trial designs, without any estimation of the likelihood of 

the selected fire scenarios. Babrauskas [44] argued that "the fire scenarios and what happen[ed] to the building 

upon encountering a given scenario, [were] items for the designer to propose to the building official. The 

building official [could] then reject the proposal, but he [or she would] have no objective grounds for doing so". 

Related to this preoccupation and in order to have a more cohesive sets of performance criteria and design fire 

scenarios across their jurisdictions, some national regulations decided to "prescribe" a priori lists of 

performance criteria and design fire scenarios. New Zealand building current regulation constitutes a typical 

example of that situation. I concede that in the short term, AHJs of New Zealand would be able to better judge 

applications based on a PBFPD process where scenarios are predefined but in the long term, I anticipate 

difficulties in applying these scenarios to very complex and unusual projects. Some difficulties are presented 

below. 

As presented in the previous point, NFPA [45] introduced a list of 8 design fire scenarios as follows: "to 

provide a comprehensive design (i.e., to demonstrate how the fire safety system will respond to a variety of 

fires), more than one scenario should be considered. It is suggested that, at a minimum, the following three 

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types of scenarios be considered: 1) High-frequency, low-consequences (typical) 2) Low-frequency, high 

consequence (high challenge) 3) Special problems scenario". The intent or the ideas behind some of the listed 

scenarios are presented in the NFPA 101 Handbook but not in the corresponding standard. I deplore the fact that 

this type of information is "lost" when editing the standard as it is more important to tell a FPE what problem 

he/she needs to solve than how he/she has to solve the problem. 

Considering "severe" (or "high challenge") a priori lists of performance criteria and design fire scenarios may 

lead in some cases, to the failure of all trial designs, even considering as many or more fire protection features 

as the prescriptive requirements. 

Regarding performance criteria of the New Zealand regulation, in 2008, Lloydd [46] indicated: "there are two 

sets of criteria: a simple set of criteria, if passed, no further analysis is required, and a more detailed set of 

criteria, for which a more detailed analysis is required. [...] The simple tenability criteria are based upon zero 

exposure of occupants to the negative effects of the fire. If occupants are kept away from all smoke and heat at 

all times, the building is considered to meet the requirements of the code [:] 

1. The clear layer height must remain at a minimum height of 2.5 m from floor level, and 

2. The maximum upper layer temperature reached shall not exceed 2000C. 

As can be quickly identified, rooms and spaces with ceilings lower than 2.5 m will not pass the simple criteria 

and more detailed analysis will always be required for these spaces. Also, the simple criteria may not be suitable 

for very large spaces where stratified layers may not form and a more detailed analysis of the conditions within 

the space may be required". 

When dealing with a list of design fire scenarios, I have similar comments: what to do when selecting the "loss 

of one exit" scenario when the building has a single main exit stairs? Based only on the basic description of this 

scenario, it may imply to the AHJ that the building may require at least two exits, or the AHJ may agree with 

the other stakeholders to "ignore" that scenario as it is permitted in the PBFPD process. What is the meaning of 

this scenario when in the prescriptive regulation (e.g. US ICC International Building Code [47]), the second exit 

is only required for a specific numbers of occupants and stories in the building, along with its main function 

(assembly, institutional...)? Besides, the scenario label itself is subject to interpretation. For a loss of exit, one 

could put the fire (i.e. untenable conditions) in the stairwells, but also anywhere in the exit path. If the exits are 

designed according to requirements, does one still have to consider the scenario where one exit is loosed? 

Regulators want more specificity regarding the scenarios characteristics (i.e. evolution of the heat release rate 

with time) because scenarios constitute the core of how the fire protection design is judged to be acceptable and 

the variability regarding their characteristics is too large. 

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Even with a list of pre-defined scenarios, there are so many parameters to evaluate in order to characterize each 

of the scenarios of any pre-defined list: the definition of the fire threat, including the location of the 1st burning 

item, the evolution with time of the heat release rate, the production of fire effluents and their spread within the 

built environment, the initial position of the building occupants (movable targets), the time required for these 

occupants to be aware of the fire condition, to realize the emergency situation and start to evacuate, the 

selection of the exit routes by the occupants and their travel speed are. This parametric characterization of fire 

design scenarios is not precise enough so the variability in interpretation of these scenarios increases not only 

among the different stakeholders but also FPEs. New Zealand regulators tried to implement these parameters, 

that is to say specify values for the different parameters of each scenario in a non-mandatory application 

guidance [46]. For example, the heat release rate evolution with time or "HRR curve" is specified as an "tsquare" curve. Nevertheless, no explanation is given on the selection by the regulators of the value of the ­

parameter: is it a mean value based on the potential fire hazard of the combustible building contents? How does 

that value correspond with the actual situation of the considered project? How much could the actual building 

content configuration vary before another value of the -parameter has to be considered by the regulators? 

For tunnel ventilation design applications, in 2007, Miclea et al. [48] gathered values of the recommended 

minimum values of the heat release rate to consider, as follows: "the UN ECE recommendations suggested a 

minimum fire size of 30 MW. This is used in many countries such as Austria, Germany and Switzerland, 

whereas provisions of 50 MW can be found in the design standards of Germany and Britain". The authors also 

compared these values with the one reached in the Runehamar tunnel tests where fire from ordinary heavy 

goods vehicles could reach as high as 200 MW. This example illustrates the fact that quantified parameter 

values embedded in the regulations certainly decrease variability in the application of the PBFPD process but 

they also need to be well documented with their applicability domain. 

In conclusion, attempts made by standard associations, and even regulatory bodies to define more quantification 

of performance criteria and design fire scenarios seemed a positive action in order to increase coherence in the 

PBFPD process applications. Nevertheless, intents and ideas behind developing fire scenarios in such lists are 

lost in their transcription into the regulatory framework, while on the contrary they should be put forward in this 

context (to explain why the situations analyzed by the scenarios should matter), instead on having the 

regulations "prescribing" more and more details on the scenario specifications (on how the FPE has to calculate 

the scenario consequences). Applications already showed some limitations and drawbacks of this concept. 

2.2.5 Challenges when comparing levels of performance between an engineering solution and the one based 

on prescriptive requirements 

The acceptability of an engineering fire protection design can be made according to a comparative evaluation of 

this design with the ones elaborated using the corresponding regulatory requirements. In some projects where 

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innovation is the main driver, like for example, the need to have beautiful, large, bright airports to accommodate 

the exponential increase of air traffic since the 1970’s, as well as the connective use of airports with nearby 

hotels and car renting or parking sites. Fig. 2-1 shows the "check in" hall of Terminal 4 Barajas airport in 

Madrid. Such wonderful airport aesthetics are without comparison with the airport ancestors provided with 

compartmented long corridors. Comparing the fire safety options of these two types of airports would not make 

sense as their designs, which constitute their true nature, are too different. 

(source: http://en.wikipedia.org/wiki/File:Barajas_terminal_4_panorama,_Madrid.jpg, in the public domain) 

Fig. 2-1. Barajas terminal 4 panorama, Madrid 

What about new performance criteria such as sustainability? Performance of a building is not exclusively 

related to life safety, which is the primary objective of most building codes (including no harm to adjacent 

building and safety of fire emergency responders as in the New Zealand regulation). Fire protection 

requirements are then mainly established according to this safety objective. The other stakeholders’ goals and 

objectives, such as property protection, heritage preservation, would require specific regulations. Standards 

exist but they are not at the regulatory highest levels [49], which "focuses on performance-based evaluation as 

an important alternative to prescriptive codes" [50]). 

Building codes authorize trade-off between different fire protection requirements, usually when the considered 

building is fully equipped with sprinklers. For example, in offices, the ICC International Building Code states 

that the maximum common path of egress travel shall not be more than 75 feet (22 860 mm) if the office 

building is not sprinklered and 100 feet (30 480 mm) if the office building is fully sprinklered [47]. Scenarios to 

be used in estimating the engineering solutions would also be used for the deem-to-comply requirements. For 

the list of selected scenarios, there is no certainty that the quantified trade-offs inscribed in the regulation would 

pass the selected scenarios. 

In conclusion, comparison of performance levels between an engineering design and a prescriptive one is not a 

trivial exercise. I assume that the rationale behind the quantification of the requirements embedded in building 

codes is based on previous "good practices", partial empirical evidence and not on system approach of the 

problem, especially when trade-offs are concerned. This rationale does not have a common background with the 

one used in the PBFPD processes, so I do not retain this form of comparison in the rest of this chapter. 

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2.2.6 Challenges related to the determination of influential factors affecting the evaluation of trial designs 

SFPE [8] lists factors affecting the evaluation of trial designs (cf. §10.2.1 of SFPE guide) but these factors are 

not clearly assessed nor always considered (sensitivity of subsystem output to design objectives, knowledge 

level [uncertainties], benefit versus cost [cost could be prohibitive and it may change the design objectives 

{cf. §10.1.5.4 of SFPE guide}], and absolute or comparative evaluation). IFEG [9] provide a list of input 

parameters and output parameters for each of the sub-systems these guidelines present: fire initiation and 

development and control, smoke development and spread and control, etc. Nevertheless, they do not provide a 

hierarchy on the relative influence of all these parameters. For these parameters needed for the quantification of 

the fire consequences, as well as other factors needed to perform a PBFPD process, no examined standards, 

guides and guidelines [7-10] established a hierarchy between the influences of these factors. Additional factor 

influences, such as the "user effect" on tools, also have to be assessed [26]. Besides, in the consulting 

environment, such assessments are difficult due to time and resources constraints. Evaluating trial designs is 

rendered complex because of multiple interconnected influences at a process level (influence in selecting 

scenarios, performing cost-benefit analysis), at a technical level (influence of the characteristics of the design 

fire scenarios) and at a political level (agreement on performance criteria). 

2.2.7 Challenges when dealing with "idealized" design features and "real life" installed and running features 

When applying the PBFPD "concept of optimization" in the design phase of a project, difficulties may arise for 

futures changes. In 2004, Ryber et al. [51] identified related minefields and proposed possible tools to 

overcome these difficulties. Besides, Stenstad and Bjørkmann [52] examined the interconnections between the 

different stakeholders involved in implementing PBFPD in the execution phase of a new project, which concern 

the "architect, the different engineering firms and contractors. Each company is responsible for a limited part of 

the building project related to their contract and will have no survey, nor responsibility for the project as a 

whole [...]. "Minor" changes may be done without anyone questioning the consequences. In this way, 

prerequisites defined in the [Fire Safety Strategy] FSS report may be overlooked and not taken care in a proper 

way". Looking at the problematic related to the use of safety margins, they indicated that the "uncertainties to 

fire safety resulting from the design, execution, administration and maintenance of a building [were] most likely 

to reduce the level of safety from that stated by the building code. We [were] fortunate that our traditional 

buildings include[d] both materials and individual elements of construction that often [left] us with considerable 

redundancies. It [was] important to recognize this when we [tried] to identify the inherited or as called the 

political level of safety", as shown in Fig. 2-2. 

Even if most of the important decisions related to a new project fire safety have to be taken during the project 

conceptual design phase, documentation and maintenance protocols of the installed fire protection measures 

have to be transmitted to the actual users of the building as these users would be the ones who would have to 

deal with a real fire event. These aspects are not included in the evaluation of the trial design. A solution could 

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be conceptually acceptable but not compatible with the actual use of the building, with or without considering 

significant changes in the building management or use. 

Safety margin 

minimum 

real 

code / 

guidelines 

DesignConstruction/execution AdministrationMaintenance 

Redundancies 

Fig. 2-2. Level of Fire Safety and the reduction due to the different processes [52] 

2.2.8 Challenges when estimating the consequences of fire design scenarios 

Tools related to the estimation of the effects of a fire (fire effects tools) have been developed separately from 

the tools related to the estimation of the evacuation process and from the tools related to the estimation of the 

structural response in case of fire. This situation arise from the fact that these three components of the fire 

protection engineering calculations were so complex and different from one another that they required these 

separate developments. Nevertheless, attempts to jointly calculate fire effects and egress are in development 

(such as FDS-EVAC co-developed by NIST and VTT). 

Life safety objectives are often analyzed through two concepts: ASET (Available Safe Egress Time) and RSET 

(Required Safe Egress Time). In 2008, Averill et al. [53] assessed that priority had been given to the estimation 

of the ASET concept. I assume that their assessment relies on the fact that FPEs are more trained to deal with 

the estimation of fire effects than the estimation of the evacuation process; because egress modeling had been a 

concern for FPEs for decades, as soon as they tried to calculate the RSET. Indeed, in 1988, Kendik [54] stated 

that an early distinction was made between two egress model categories: movement models and behavior 

models and in 1999, Shields [55] presented a possible path to follow in order to develop human behavior 

knowledge as "hard science alone cannot solve the “fire problem”". This dichotomy in solving the “fire 

problem” can be seen, for examples, in the fact that there is still no or seldom feedback of the evacuation side to 

the fire side (i.e. building occupants closing doors while escaping) or evaluation of the counter flows of fire 

fighters and emergency responders and their actions on people and fire. Challenges are then related to the 

education of the FPE, who must not only be trained to estimate fire effects, but also evacuation of building 

occupants and structural response in case of a fire. 

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Besides, it is necessary to verify the appropriateness of tools to be used for a given the application, as well as 

the user's ability to use such sophisticated research tools. Documents published by SFPE [26,56] ISO [57] or 

ASTM [58,59,60,61] provide generic guidance on the use or on the validation of computer models. In addition 

to the generic status of these guidelines and standards, it should be noted that the application of such documents 

has to be reassessed with updated versions of the same models and with new models. One example of applied 

document concerns a fire detection computer model [62]. It should be noted that I was not able to find any 

document which provides guidance on the interactions of model uses to assess fire effects, occupant evacuation 

and response of structural building elements. 

2.2.9 Challenges when adapting literature values, when available, to use in models 

As previously presented in this chapter, consensus of the fire protection engineering profession and the 

regulators should be found for the values of the "fire effect criteria" so that reports can be published regarding 

these criteria. Governmental institutes NIST [63] or INERIS [64], international societies such as SFPE [65] or 

ISO [66] should provide such reports, so national regulators and AHJ could reference the recognized values 

and, if necessary, adapt them for their own purposes. Current works in ISO TC92/SC3 are dedicated to the 

revision of an International Standard providing guidelines for the estimation of time to compromised tenability 

limits [67]. 

In any engineering practice, injecting appropriate data in tools is as essential as using the appropriate tool in 

order to solve a given problem. Care should be taken when selecting and using data from any source as: 

- Data obtained from experiments performed decades ago does not necessary represent current data as 

material properties and people characteristic distributions constantly evolve, 

- Some data needed to use tools is still missing so FPEs have to use their "expert judgment" to adapt the 

available experimental data to use with a chosen tool, and 

- Tools (models) also evolve with knowledge of the phenomena they represent. Experimental data is usually 

collected in order to supply validation points for a model. The data collection process is then elaborated in 

order to coincide with the model paradigm. In other words, the data may be model dependent; changing the 

model may disqualify a data validation set to be used in another model. 

Current PBFPD processes emphasize on the importance of using appropriate data with appropriate tools. As an 

example, Part 3 of IFEG "provides a selection of data that may be used in applying [its] methodologies 

[gathered in its] Part 2 or other chosen methodologies. This does not preclude the use of other data that might be 

chosen by the fire engineer and that are acceptable to regulatory authorities or certifiers. Caution should be used 

in applying data because it may not be relevant as a result of: 

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- New methodologies 

- New technologies 

- New materials 

- Varying regulatory requirements 

- Cultural differences 

- Construction practices". 

Nevertheless, the current PBFPD processes fail to provide the necessary level of detail with which the FPEs and 

the different stakeholders, including peer reviewers, have to scrutinize the datasets used while performing any 

PBFPD process. 

Without validated repositories for input data, FPEs are forced to spend time and resources to look for 

appropriate data and demonstrate to the stakeholders that their chosen datasets can be used for the application 

they are analyzing. This statement is also valid for a researcher who usually starts his/her research by collecting 

data already found by prior researchers and relevant to his/her particular study. 

Concerning the values of all the parameters needed in order to perform a calculation of the consequences of a 

fire, it should be noted that attempts were or are currently made to develop repositories of data collections 

usable by FPEs: 

- Fire data was made available by the US National Institute of Standards and Technology (NIST), which 

created the Fire And Building Educational Resource Collection (FABERC) [68]. This database is no longer 

accessible via "faberc.org", but some experimental results from fires conducted by NIST still can be found 

at its own website. 

- The need for egress data collections was advocated by Fahy and Proulx [69]; Gwynne [70] with NIST 

support started to develop a web portal to support such a database, its structure being elaborated and ready 

for beta-testing. 

- Standardized methods are in progress (i.e. NFPA 557 in the USA [71]) in order to collect basic data such as 

fire load and reliability of systems in a coherent and harmonized manner, which really permit to collect, use 

and compare data from different studies. 

As long as the FPE community is not ready to consolidate such databases and standardize procedures to collect 

and apply data in order to provide appropriate data to use in any PBFPD process, FPEs and stakeholders will be 

required to spend unnecessary time and resources to find data and validate its use for each and every project. 

Even with the most elaborate and sophisticated PBFPD process, using inappropriate data produces erroneous 

results which may lead to a building performance dramatically below its expected level of performance. 

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2.3 Summary of the challenges related to the use of current PBFPD processes 

A large number of articles in journals and conference proceedings that describe challenges and concerns 

regarding the use of PBFPD processes, published as early as the first drafts of these processes, and covering the 

last two decades, have been analyzed. It has been determined that significant challenges still exist in the 

application of these processes in practice and that major changes are needed to address them. 

1. Applying generic guidance to specific projects 

The PBFPD processes currently included in codes, standards, guides and guidelines were written at a time when 

it was a priority to introduce the global concepts of the PBFPD process, to model all the phenomena, and to 

determine and assess the influence of critical components of the PBFPD process. With this purpose in mind, 

they had to be generic in order to be used as widely as possible. After decades of application of these processes, 

it appears that this wide applicability has turned out to be a significant drawback, leading to a number of 

specific challenges as presented here and summarized below. For this reason, it is proposed that the next 

generation of guidelines will have to include more details and specificities of the considered types of projects, to 

which all the engineering process has to be refocused on. 

2. Defining, using and quantifying the performance/acceptance criteria 

As quantified in the current PBFPD processes, performance criteria should actually be called "fire effect 

criteria". The terminology "performance criteria" should describe the actual level of performance achieved by 

the considered project, for each of its objectives agreed among its stakeholders. Research to attain a consensus 

for criteria assessment between the different engineering disciplines should be done, not only for building 

occupants, but also building contents relevant to the stakeholders (i.e. important piece of equipment, electronic 

cabinet used for process safety, priceless artifact) as well as environmental ecosystems potentially affected by 

the fire itself and the chemicals used for its extinguishment. 

3. Selecting fire design scenarios 

Attempts made by standard associations and regulatory bodies to define more quantification of performance 

criteria and design fire scenarios seemed a positive action in order to increase coherence in the PBFPD process 

applications. However, the intents and ideas behind developing fire scenarios, as ultimately reflected in such 

lists, are generally lost in their transcription into the regulatory framework. This is unfortunate because these 

intents and argument should be provided in context with the scenarios to explain why the situations analyzed by 

the scenarios should matter, instead on having the regulations "prescribing" more and more details on the 

scenario specifications or how the FPE has to calculate the scenario consequences. 

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4. Comparing the levels of performance between an engineering solution and the one based on prescriptive 

requirements 

Comparison of performance levels between an engineering design and a prescriptive one is not a trivial 

exercise, yet that is a common approach taken. I assume that the rationale behind the quantification of the 

requirements embedded in building codes is based on previous "good practices", partial empirical evidence and 

not on system approach of the problem, especially when trade-offs are concerned. This rationale is not 

appropriate for a PBFPD process, and is not recommended without being made much more transparent (which 

is difficult, especially given (3) above). 

5. Determining the most influential factors affecting the evaluation of trial designs 

Current PBFPD processes list factors affecting the evaluation of trial designs, but these factors are not clearly 

assessed nor always adequately considered with respect to such attributes as sensitivity of subsystem output to 

design objectives, knowledge level (uncertainties), benefit versus cost (cost could be prohibitive and it may 

change the design objectives), or absolute versus comparative evaluation. There is no hierarchy between the 

influences of these factors. Additional factor influences, such as the "user effect" on tools, also have to be 

assessed. In the consulting environment, such assessments are difficult due to time and resources constraints, 

thereby making them less likely to be undertaken. Likewise, evaluating trial designs is rendered complex 

because of multiple interconnected influences at a process level (influence in selecting scenarios, performing 

cost-benefit analysis), at a technical level (influence of the characteristics of the design fire scenarios) and at a 

political level (agreement on performance criteria), and lack of data, time and resources means that the 

evaluation required does not always get done at a level that it should. 

6. Dealing with "idealized" design fire protection measures and "real life" installed and running measures 

At present, most PBFPD processes consider "idealized" representations of future actual conditions, often times 

not accounting for how buildings are used and the state of systems over time. At the time of design, decisions 

may be made without all stakeholders being involved, and without the stakeholders understanding the 

implications for the future. Even if the fire protection "design" is the most important aspect of any building 

design project, things may change during construction that need to be documented and accounted for, and 

maintenance of systems and consideration of how the systems performance with respect to normal operation of 

the building becomes critical once the building is occupied. These aspects are not explicitly included in the 

evaluation of the trial design by current PBFPD processes. As a result, a "design" solution could be 

conceptually acceptable but incompatible with the actual use of the building, with or without considering 

significant changes in the building management or use. 

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7. Estimating the consequences of fire design scenarios 

While an integrated approach to building fire performance is the target of current PBFPD processes, estimation 

of consequences is not at all integrated. Life safety objectives are often analyzed through two concepts: ASET 

and RSET. Tools related to the estimation of the effects of a fire (fire effects tools) have been developed 

separately from the tools related to the estimation of the evacuation process and from the tools related to the 

estimation of the structural response in case of fire. Data are often lacking for all required analyses and 

shortcuts are taken. As a result, these analyses (fire effects, evacuation, structural fire performance) are typically 

undertaken in isolation. As a result, it is not always clear how factors such as fire and evacuation interactions 

are addressed (e.g., occupants opening and closing doors, which can change burning characteristics), or which 

parts of the process are most sensitive to changes from initial design assumptions, or where greatest sources of 

uncertainty and variability exist. Challenges also exist with engineers selecting appropriate tools to be used for 

given the applications, as well as the user's ability to use sophisticated research tools in design. 

8. Adapting literature values, when available, to use in models 

In any engineering practice, use of appropriate data in analytical or computational tools is as essential as using 

the appropriate tool in order to solve a given problem. Care should be taken when selecting and using data from 

any source as: 

- Data obtained from experiments performed decades ago does not necessary represent current data as 

material properties and people characteristic distributions constantly evolve, 

- Some data needed to use tools is still missing so FPEs have to use their "expert judgment" to adapt the 

available experimental data to use with a chosen tool, and 

- Tools and models also evolve with knowledge of the phenomena they represent. Experimental data is 

usually collected in order to supply validation points for a model. The data collection process is then 

elaborated in order to coincide with the model paradigm. In other words, the data may be model dependant; 

changing the model may disqualify a data validation set to be used in another model. 

However, current PBFPD processes fail to provide the necessary level of detail with which the FPEs and the 

different stakeholders, including peer reviewers, have to scrutinize the datasets used while performing any 

PBFPD process. Without validated repositories for input data, FPEs are forced to spend time and resources to 

look for appropriate data and demonstrate to the stakeholders that their chosen datasets can be used for the 

application they are analyzing. This statement is also valid for a researcher who usually starts his/her research 

by collecting data already found by prior researchers and relevant to his/her particular study. 

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2.4 Characteristics of a new paradigm 

As summarized above, several challenges with current PBFPD processes have been identified. Even where 

found in the literature, successful applications of PBFPD processes showed that addressing the challenges are 

currently costly in time and resources, in order to solve the engineering problem (technical level) and get an 

agreement among all the involved stakeholders (political level). Because the current PBFPD processes are 

generic, it seems difficult to incorporate any feedback of the successful applications into these processes in 

order to overcome the presented challenges and therefore reduce the uncertainties and concerns associated with 

them. In addition, the current PBFPD processes are centered on the study of the fire protection measures, which 

sometimes can lead to differences on the way these measures are designed and then used when the building is 

occupied. Furthermore, designers are not taking as full advantage of data and tools, for the types of applications 

being addressed, as they can or perhaps should. 

In order to overcome these challenges, it is suggested that the solution is to: (1) re-center the PBFPD process on 

its application subject, that is to say the system formed by the building and its occupants, (2) create PBFPD 

processes that are specific to different types of occupancies, and (3) to provide a mechanism to help FPEs select 

the most appropriate tools and data for the types of applications they are addressing. To address (1), by 

integrating the study of the fire protection measures as a component of the overall study of a "buildingoccupant" system, challenges with taking fire systems out of context of building operations could be identified 

and then hopefully minimized. In addition, this shift in the paradigm, from the study of the fire protection 

measures to the whole "building-occupant" system not only allows to extract all the data required to perform the 

analysis but also to characterize the context for which the analysis is carried out and which determine the 

overall performance of the system vis-à-vis the fire threat. Explanations related to this paradigm shift as well as 

the main characteristics of the new paradigm based on a "building-occupant" system are detailed in the 

following chapter of this dissertation. To address (2), by developing system-specific guidance, a much greater 

level of guidance can be provided, thus minimizing challenges in application and interpretation of data, use of 

tools and methods of evaluation. A new risk-informed PBFPD process, based on the system paradigm, has been 

elaborated, which separates the technical decisions to be elaborated by the FPE and the political decisions to be 

taken by the involved stakeholders. The risk-informed PBFPD process that would be able to overcome the 

challenges listed in this chapter is presented in Chapter 4 of this dissertation. To address (3), by creating 'test 

bed' environments, displayed on an web-platform, FPEs and all other interested parties are expected to share 

their own knowledge on tool uses and therefore fill the need for guidelines to aid the selection of appropriate 

fire consequence analysis tools for specific types of fire protection engineering applications [72]. 

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2.5 Conclusion of this chapter 

Challenges in applying current PBFPD processes arise from technical and political levels. Challenges still exist 

concerning the definition/quantification of the strategic elements of any PBFPD process: the performance 

criteria (which current denomination should be changed to "fire effect criteria"), design fire scenarios, use of 

tools to quantify the trial designs. Efforts are made to consolidate databases gathering information related to 

buildings, fires and occupant behaviors but it is still necessary to make such databases available for the whole 

engineering community. Besides, validation and verification domains related to the tools still need to be defined 

according to the engineering problems these tools are used to solve. A new proposition has been elaborated in 

that matter [69]. Challenges related to the difference between the building design and its numerous alterations 

during its lifespan should be better considered in the examined PBFPD processes. 

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3.	 USING A SYSTEMS APPROACH TO ASSESS HOW DISRUPTIVE EVENTS 

AFFECT BUILDING OVERALL PERFORMANCE 

The main drivers for performance-based design (PBD) are demands from users for better building use 

performance, in conjunction with a change in legislation allowing a broader use of the PBD option instead of 

prescriptive requirements. Within a PBD framework, the demand of the "end users" of the building become 

priorities [1] so that PBD provides a more "client" oriented process [2] than the one used when following 

building code regulations. 

Performance-based design (PBD) applies to all the components of a building project related to, among others, 

acoustics, aesthetics, operability, sustainability, and safety. Then, it involves numerous actors including, on one 

hand, the building users who should define the level of performance of the building and on the other hand, the 

building industry which should create optimal solutions in order to achieve this level of performance within a 

regulatory framework established by policy makers. 

Because of the complexity of the engineering thinking related to these building components, PBD guidance has 

been segmented such that each engineering discipline has to consider separately how clients' objectives 

connected with each of the building components should be achieved. This statement is not only valid for 

building components dedicated to the normal use of the building (e.g. mechanical components including 

heating, ventilation, and air conditioning (HVAC) and plumbing) but it also concerns building components 

installed to address disruptive events, such as fires or earthquakes. In other words, some PBD guidance has thus 

far been elaborated to treat fire safety objectives exclusively [3] while other guidance only addressed 

earthquakes [4] as these hazards are very specific and the engineers quantifying these hazardous situations have 

specialized expertise. 

However, in practice, the building end users are not really interested in the performances of different building 

components as they wish to experience, on a daily basis, the performance of the building as a whole [5]. As 

such, the design team individual entities; rather members dealing with the multitude of building components 

have then to co-operate in order to achieve this seamless daily performance [6]. 

The research presented in this chapter originated from a review of decades of worldwide experience of the 

performance-based option for fire protection design, which identified shortcomings in the interpretation, 

application and implementation of performance-based fire protection design (PBFPD) processes. This review is 

presented in the previous chapter of this dissertation. I found that the application of these processes, which the 

aim of is centered on the design of fire protection measures, and not building performance, may lead to the 

possibility that these measures, deemed appropriate at the building design stage, might be ignored or worse 

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"rejected" by the building end users when needed the most, since fire is not a daily concern of these users. I 

realize that this can be generalized to any disruptive event and mitigation strategies. 

This chapter presents the outcomes of my research related to the treatment of disruptive events on the overall 

performance of a building project, using fire as an example: 

- first, I define a system formed by specific building types and their associated occupants, so as to 

characterize the nature of disruptive events and theirs effects on the overall performance of that system; 

- second, I establish a risk informed performance-based design process which would be applicable to any 

disruptive event and include a step evaluating the integration of the protection measures into the considered 

system. 

3.1	 Definition of the daily performance of a "building-occupant" system and its 

decrease during a disruptive event 

Primary stakeholders in a building project, including the building owner and the potential users, generally 

define building performance objectives in terms of the everyday uses of the building. For a hospital, this 

performance is related to the type of treatments offered, the number of patients who can be treated, the types of 

equipment and services needed to treat patients, and so forth. For a school, performance is related to delivering 

education to the target student population, the number of registered students, the numbers and qualification of 

teachers or faculty required to deliver education, etc. For a museum, it is related to the exhibits and holdings, 

number of exhibition attendees who can be accommodated, security of the holdings, etc. Unfortunately, the 

owners and operators of these buildings do not always think about events which can disrupt this daily use. This 

has an impact not only during use, but with respect to decisions made at the design stage. 

Disruptive events can be of different natures [7], such as:
 

- supplier business disruption leading to operational vulnerabilities, 

- fires, earthquakes, severe weather, accidents or terrorism leading to hazard vulnerabilities,
 

- currency exchange fluctuations leading to financial vulnerabilities,
 

- new foreign competitors leading to strategic vulnerabilities.
 

Such disruptive events can significantly impact the operation of a building and the mission it supports. If the 

building owner and other key actors are unprepared, the disruptive event can have catastrophic effects on 

continued operations [8]. Because of my experience, I will be focusing, for this chapter, on fires as an example 

of a class of disruptive events, as well as an example on how my paradigm of study, centered around a "building 

occupant" system differs from the one considered in the current PBFPD processes, centered around the fire 

protection measures themselves. 

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3.1.1 Introduction of the "building-occupant" system paradigm 

In many countries, buildings are classified in terms of the general class of use, such as places of assembly, 

business occupancies, residential, and so forth. However, these general descriptions lack the complexity to 

describe the interaction of the building users in the context of the building. To address this, I looked to identify 

a more appropriate "building-occupant" system. In order to define the system formed by specific building types 

and their associated occupants, which I call "building-occupant" systems, I first looked at building code 

classifications. To frame this discussion, I focus on healthcare occupancies. I also focus on the situation in the 

USA. 

An obvious way to categorize the different existing "building-occupant" systems is to follow the classification 

established in building regulations. For example, in the USA, Chapter 3 of the International Building Code 

(IBC) established by the International Code Council (ICC) provides 10 different groups [9]. The purpose of the 

building (or part of the building) determines the group of the building (or part of the building). "Sections 303 

through 312 of the ICC IBC identify the occupancy characteristics of each of the 10 groups. In some of these 

sections, specific group classifications having requirements in common are collectively organized such that one 

term applies to all". For example, Groups I-1, I-2, I3, and I-4 are individual groups for Institutional-type 

buildings. The general term "Group I", however, includes each of these individual groups. Prescriptive 

requirements are defined for each of these groups, with specific requirements when applicable: for example, 

Section 403 adds requirements if the building qualifies as a "high-rise" building; Section 404 adds requirements 

related to the presence of an atrium in the building; Section 407 adds provisions for occupancies in Group I-2. 

By reviewing the occupancy group classification of the ICC IBC, I determined that this classification is too 

coarse to take into consideration all the specificities of different "building-occupant" systems. For Institutional 

Group I-2 defined according to the ICC IBC classification, detoxification facilities, nursing homes, hospitals, 

and mental hospitals do need the same requirements. In all these facilities, populations are vulnerable, unable to 

evacuate without assistance but they are very different and the building systems are also very different, as 

shown in Fig. 3-1. A classification, such as the one established in ICC IBC, is a "good" start but still 

necessitates going in a deeper taxonomy level to clearly define a proper "building-occupant" system. 

Related to this point, Lataille [10] indicated that "prescriptive codes apply to facilities with widely varying 

characteristics. For example, the same prescriptive codes apply to an office building whether it has one or 

several stories, small or large building footprint, or low or high combustible loading. Different provisions in 

these codes might apply to different buildings, so the prescriptive protective scheme can vary from building to 

building". This statement issued for prescriptive requirements can be extended to the PBFPD processes. 

35 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

a) Child care facility, source: 

http://www.flickr.com/photos/shaggypaul/351385178/, 

free to share and remix with the attribution of the work 

to "Shaggy Paul" 

b) Hospital, source: 

http://www.flickr.com/photos/usnavy/ 

5913202904/sizes/o/in/photostream/, 

free to share and remix with the 

attribution of the work to Official 

U.S. Navy Imagery 

a) Nursing home, source: 

http://www.flickr.com/photos/13384589@N00/2780553 

606/, free to share and remix with the attribution of the 

work to by "Robinsan" 

Fig. 3-1. Examples of facilities under the ICC IBC Institutional class (I2) 

Performance-based building codes present an opportunity to go beyond ‘simple’ classifications and consider 

more specific "building-occupant" system features. However, this requires the stakeholders and design team to 

focus more effort on describing the system as part of the PBFPD process. The structure of some PB building 

codes helps facilitate this. For example, one distinction of the ICC Performance Code (ICC PC) approach [11] 

from the IBC and from many other performance building codes is its classification of the building in terms of 

performance groups (Section 302.1 of ICC PC): "the objective of the assignment of use and occupancy 

classification is to identify the primary uses of buildings and facilities, and portions of buildings and facilities, 

and to identify risk factors associated with these uses, in order to facilitate design and construction in 

accordance with other provisions of this code". This classification is useful to demonstrate that the PBFPD 

process has to take into consideration the importance of the building for societal expectations in respect of the 

level of safety. 

As the ICC PC is one of the building codes developed by ICC, the building uses are to be taken from the 

prescriptive "Uses and Occupancy Classification" chapter of the ICC IBC. Nevertheless, the ICC PC 

performance group classification goes beyond the IBC classification in considering the building "importance" to 

the community, which allows for making a distinction between different buildings inside a same IBC occupancy 

classification. For example, a hospital that is intended to remain functional after an earthquake or other hazard 

event, to care for those who may be injured in the event, can be designated as having a higher level of 

performance than other healthcare facilities in the same geographical area. As such, a higher level of 

performance and resiliency during and after a hazard event is warranted. 

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Looking at other systems, I found the classification by the US Bureau of Census [12] more useful than the ones 

defined in building codes in defining more precisely the "building-occupant" systems . In this taxonomy a 

distinction is made between child day care (with the code 624410), general hospitals (with the code 622110), 

Psychiatric and Substance Abuse Hospitals (with the code 62221) and nursing care facilities (with the code 

62311). In addition to providing a better "building-occupant" system descriptor, a benefit of using this 

taxonomy is that the Bureau of Census periodically collects information concerning each of its categorical 

areas, which can be helpful in the performance assessment. 

Based on this taxonomy, I defined a "building-occupant" system as a system defined by a structure (i.e. 

building) inside which occupants are primarily engaged in a specific activity. This activity is quantified (e.g. 

activity number carried out by day or week) and then the performance of the system is estimated by the level of 

this activity. 

Occupants are defined as persons who are physically inside the system, independently of the duration of their 

stay. Building components are defined in my paradigm as physical portions of the system which can include, for 

example, spaces dedicated to a particular occupant activity of the system or in support of that activity (e.g. 

HVAC system). 

If I examine a hospital, I can see that there are different building areas which can be identified according to the 

functions they provide, such as reception areas, emergency rooms, examination rooms, operating rooms, patient 

rooms and intensive care units. I call any such area which can be grouped by function as a "functional" zone, as 

they are created to fulfill the functions related to the daily objectives of the facility. In addition, there are utility 

systems and areas which provide support functions, such as power, heating, ventilation and air-conditioning 

(HVAC), throughout the facility. These utility systems can be located in "utility" zones (mechanical rooms, 

electrical rooms, cafeteria...) or throughout the building (such as the HVAC system). When designating zones, 

care should be taken to define them based on the "building-occupant" system characteristics of importance. It is 

also important to identify direct and indirect relationships. 

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Hospital 

Reception Staff + in-patients (mostly mobile) + visitors 

Examination rooms Staff + in-patients (not mobile and mobile) 

Emergency rooms Staff + in-patients (not mobile) 

Operating rooms Staff + in-patients (not mobile) 

Intensive care units In-patients (not mobile) 

Patient rooms In-patients (not mobile and mobile) + visitors 

Fig. 3-2. People description according different functional zones of a hospital 

For example, Fig. 3-2. illustrates the required level of detail for different functional zones of a hospital, 

describing the types of population in each of the zones. For example, people located in the reception area are 

future in-patients, visitors and staff and almost all of them are mobile and conscious. This is important as they 

would require no or little assistance in case of a hazardous disruptive event such as a fire. In-patients located in 

emergency rooms or in operating rooms are undergoing surgery and are connected to life-supporting machines. 

This is important as extracting them during a fire would require following procedures and requiring time that 

may not be compatible with a rapidly growing fire [13]. In addition, while a utility zone supporting a reception 

area may be important to facilitate the comfort of the occupants, a utility zone supporting an operating room 

functional zone is essential. If a fire occurs in the utility zone supporting a reception area the impact in the 

reception area could be limited to an ‘inconvenient’ loss of power or lighting. If a fire occurs in the utility zone 

supporting the operating room, the impact could be life-threatening. 

To summarize, characteristics of occupants within specific locations of a building, as well as the intended 

function of spaces in a building and contents in those spaces which are essential to achieving the required 

function needs to be clearly understood, identified and categorized. This constitutes essential information 

required by the Fire Protection Engineer (FPE) in order to address stakeholder objectives for "buildingoccupant" systems when elaborating a fire safety strategy. However, no current PBFPD process directs an FPE 

to examine a building at such a level of detail, explains the reasons why such a level of detail is important, or 

provides guidance how to approach the assessment. In large part this is because current PBFPD processes are 

focused too much on the fire event itself instead of being target-oriented, focusing on the objectives of concern 

within the specified functional zones or a well-defined "building-occupant" system. 

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3.1.2 Characterization of the effects of a disruptive event on the performance of a "building-occupant" 

system 

To show the importance of considering the building to be analyzed as being part of a system network, let us 

describe the events that started with a small fire in a manufacturing plant in USA and ended up with a 

US$2.34 billion loss for one of the plant clients. This example is taken from Sheffi's book "The Resilient 

Enterprise" [7]. 

On March 17, 2000, lighting struck the industrial plant of Philips NV, located in Albuquerque, New Mexico, 

USA. As a consequence a small fire started within the facility but was extinguished by sprinklers and staff in 

less than 10 minutes. There were no injuries and the fire fighters arrived at the plant just to record a minor 

blaze. From a fire protection engineering design perspective this could be considered a success, with systems 

operating as intended. However, due to ensuing activities, the damage to the plant contents and disruption to the 

plant activity was tremendous. 

So why was the disruption so significant? First, the plant was engaged in manufacturing of semiconductor chips 

for some 30 clients, including the mobile phones companies Nokia and Ericsson, whose orders accounted for 

40 percent of the Albuquerque plant’s production. Indeed, a semiconductor manufacturing facility such as this 

cannot tolerate any dirt or particulate in normal activities, in any of its clean rooms, much less soot in case of a 

fire. Not only did the fire destroy the chip batches in the furnace (with an equivalent of thousands of mobile 

phone production) but also smoke, soot and the tramping of staff and fire fighters from the fire scene (in the mix 

of dirt and water) contaminated chips at every stage of the production, increasing that loss to millions of mobile 

phone chips. The losses for Philips did not stop at the ones related to property damage. Removing the dirt from 

the clean rooms implied that the production would be back up after one week. This was the Philips estimation 

right after the fire, but two weeks later, Philips staff realized that the disruption caused by the fire would take 

weeks before production could restart. When two of the main clients of Philips, Nokia and Ericsson received the 

call from Philips on March 20, 2000, they each dealt differently with this situation, which ended up with two 

very different business outcomes. 

As soon as it received the call, Nokia started to work closely with Philips and other of its providers so to 

maintain its own production of mobile phones and satisfy its customers in a period of time when demand for 

this type of product was booming worldwide. Ericsson’s reaction was different: they treated the fire incident at 

the Philips plant as a "technical matter" which would result as a chip production disruption of one week only, 

which is something that could easily be taken care of. Unfortunately for Ericsson, the disruption lasted longer 

and by the time it realized the size of the disruption, it was too late and Ericsson failed to deliver mobile phones 

to its customers. 

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As a result of the small fire that occurred in 2000 at the Philips Albuquerque plant, Philips's chip sale loss, 

estimated to a US$40 million, was almost covered by a 39 million Euro settlement with its insurance company; 

this loss only accounted for 0.6 percent of the US$ 6.8 billion semiconductor global benefits of Philips for 2000. 

Having failed to deliver its new generation of mobile phones, Ericsson reported losses between US$430 and 

US$570 million in the first disruption-affected quarter, due to a lack of parts, that is to say more than ten times 

Philips' losses. In addition to the fire disruption effects, incorrect product mix and marketing problems are to be 

blamed for Ericsson's US$2.34 billion losses in the mobile phone division by the end of 2000. This situation led 

to a Sony-Ericsson merging for designing, producing and marketing mobile phones, in April 2001. In addition 

to its competitor economic situation, Nokia's fire disruption treatment helped to increase its percentage of the 

mobile phone market. 

Fig. 3-3. illustrates the profile of a disruption of the system, adapted from [7] for a fire disruption, based on the 

aforementioned Philips fire. Prior to the fire, the plant is performing at a certain level, i.e. it is manufacturing (x) 

chips for its clients. The disruptive event occurs (fire on March 17, 2000) and the performance of the plant 

decreases, leading to a full impact of a completely stopped production. In this case, the performance of the plant 

went down to zero for weeks. The full impact was the sum of the direct consequence of the fire (damage to the 

furnace and smoke spread) and of the indirect consequence of the fire fighting operations (staff and fire fighters 

walking all around the plant and contaminating all the remaining furnaces). The recovery time was not the 

expected one week but several weeks. A long term impact was observed, as Nokia engineers sent to the Philips 

plant in the recovery phase ended up with increasing the pre-event production rate. 

For the authority having jurisdiction (AHJ) approving the use of the plant, the life safety objective was not 

compromised. Related to fire safety, the plant could have been "code compliant" or designed to perform as well 

as a building provided with regulatory requirements. With regard to property protection objectives, the fire did 

not lead to severe damage of the production line in itself, but it contaminated all the production (with the 

involuntary help of the staff and fire fighters). It should be noted that Philips adopted a risk transfer towards 

insurance companies and hardly "suffered" from the disruptive event. On the long term, even if its premium 

may be more expensive, the subsequent boost of production may have compensated for the monetary loss. 

However, not all entities that suffer such as disruption are so lucky [8]. 

40 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Pre- event 

"chronic" state Post- event 

"chronic" state 

Fire disruptive event 

Long term 

impact 

Restarting 

production 

Preparation for recovery Recovery Time 

Performance of the Philips Plant: daily number of chips produced

The 10 minute fire is extinguished by sprinklers and staff intervention 

Chips on the furnace where the fire started are lost 

Chips on all the plant are lost andthe whole plant production is stopped

Several weeks to restore the clean rooms 

Smoke spread and tramping of staff and fire fighters from the 

fire scene (in the mix of dirt and water) contaminate chips at 

every stage of the production 

Full impact of the fire event 

Fig. 3-3.	 "Disruptive event" profile of the Philips Plant fire (Albuquerque, New Mexico, USA), March 17, 

2000, adapted from [7] 

In the "building-occupant" system paradigm, fire is one of many disruptive events that may (or may not) occur 

during the lifespan of a building. In current performance-based fire protection design (PBFPD) guidelines, the 

design for fire is focused on the fire scenario only: from the fire ignition to the fire extinguishment. This runs 

the risk of ignoring how the normal operations of the building will influence human actions and systems when a 

disruptive event occurs. 

So, I consider the system formed by the building and its occupants, and analyze the fire as a "disruptive event" 

or perturbation of the "building-occupant" system. Independently of providing safety to its occupants in case of 

emergencies, a building is designed, operated and maintained to perform objectives that correspond to the 

everyday uses of a building, objectives that I qualify as "chronic". Objectives associated with emergency 

situations related to disaster events, including natural hazards, technological hazards and terrorism, that may 

occur or not during the life span of the building are then qualified as "acute". 

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3.1.3 Key-concepts of "building-occupant" systems
 

In order to summarize my "building-occupant" system paradigm, I have several key concepts:
 

- Functional zones: spaces which are directly linked to the performance of the system (e.g. in hospitals, 

visiting areas where patients are checked in, patient rooms where patients are being prepared for surgery, 

operating rooms, intensive care units and patient rooms where patients recover before checking out); 

- Utility zones: spaces which indirectly contribute to the performance of the system, often providing support 

to the "functional zones" (e.g. storage rooms, electrical rooms, mechanical rooms); 

- Targets: key elements who’s performance is of concern within systems (the actors or users of the functional 

zones). For example, targets can be building occupants (patients including their visiting families and 

friends and staff in hospitals, pupils and teachers in schools) or building contents (important piece of 

equipment required to contribute to the performance of the system such as a newly developed micro-chip in 

high tech industry or a priceless artifact in a museum); 

- Chronic states of the system: which represent the situations of the system while it is operating as designed 

or after each modification of its design (e.g. normal use of the system). 

- Chronic objectives: objectives the system is designed or subsequently modified, to attain during its chronic 

states; 

- Disruptive events: every possible event (technological events, natural events, socio-economical events) 

having an effect on the performance of the system. A disruptive event lasts between two chronic states of 

the systems. 

- Acute objectives: objectives the system is designed or subsequently modified, to attain during disruptive 

events; 

- Event effects: damaging effects of a disruptive event on a target. These can be ‘direct effects’ or ‘indirect 

effect.’ With respect to fire as a disruptive event, "direct effects" reflect fire-induced damage upon targets, 

such as heat, toxic, corrosive, irritant effects. "Indirect effects" reflect loss of building components which 

are vital for the targets to perform in the system. For example, a fire can through ‘direct fire effects’ such as 

heat directly damage power cables to a life supporting equipment, which then has an indirect effect on the 

safety of people connected to this equipment. 

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3.2 Identifying and avoiding competing objectives within a "building-occupant" system 

Generally speaking, a "building-occupant" system is designed by architects to perform according to "chronic" 

objectives. From a societal point of view, a "chronic" objective for hospitals is to cure sick or injured patients, 

and for schools to educate people. However, there are also have societal goals to safeguard the most vulnerable 

populations. Because society does not want patients or pupils to suffer from a potential fire that can occur in the 

respective buildings they use, a life safety objective is added to the performance of these buildings, and any 

other type of building or built environment for that matter. While life safety from fire is the focus of most fire 

protection engineering analyses, fire protection measures are only one component of the "building-occupant" 

system, and in some cases competing objectives may exist. 

3.2.1 Fire safety objective competing with "chronic" objectives established at a design stage 

When looking for the goals and objectives that are relevant for the different stakeholders involved in a project, a 

FPE also has to verify that the safety objectives related to the fire risk in the system are not competing with all 

the other stakeholders' objectives. Let's see how this point is already considered in the current PBFPD 

processes. 

For example, the International Fire Engineering Guidelines (IFEG) [14] indicate that "in addition [to general 

regulatory objectives], the client may have various non-fire related objectives for the building design that 

impact on the fire safety of the building. For example, the client may require: 

- Increased security 

- Extensive natural lighting 

- An open plan layout 

- The use of new materials 

- Measure to improve energy efficiency and sustainability 

- Flexibility for future uses 

- Low life-cycle cost". 

Unfortunately, the IFEG do not provide any guidance on how to consider these additional objectives, which can 

be competing with the ones related to fire safety. As a result, there is currently no guidance for managing 

competing objectives in current PBFPD processes during the design stage. If the FPE happens to identify and 

address such issues through discussion with stakeholders, it is more by experience or chance than by direction. 

43 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

3.2.2 Fire safety objectives competing with "chronic" objectives established after the design stage 

Building stakeholders may decide to establish additional "chronic" objectives, a long time after the design 

phase, when the building is actually operating. For example, as a result of the 11 September 2001 events, 

increased security at airports multiplied check points that may impede safe egress capabilities in the case of an 

emergency. It should be noted that increased security has now become a "chronic" condition, not only for that 

type of transportation but also in major crowd gathering configurations and events. It should be noted that 

adding more security check points concentrate people in certain areas, people that are managed to follow 

predefined and controlled paths. This configuration induces a competition between the security crowd 

management and the needs for efficient and safe accessible escape routes in the case of an emergency, fire or 

other disrupting event. Not only does this security driven "chronic" condition compete with the conditions 

employed for dealing with emergency situations, but it also competes with a previous "chronic" objective of the 

architectural design to have uncongested pedestrian movement in the airport, as well as the aesthetic goal to 

have passengers walking in a quiet, spacious environment (compare Fig. 3-4. which visually translates the ideal 

vision of the designer with Fig. 3-5. which illustrated the real situations of airports). 

a) Barcelona Airport Terminal 1
 

source: http://www.flickr.com/photos/francesc_2000/4583309008/, 

free to share and remix with the attribution of the work to
 

Francesc_2000
 

b) Hong Kong Airport Terminal 2
 

source: http://www.flickr.com/photos/gkpics/953052759/, free to
 

share and remix with the attribution of the work to jgmarcelino
 

Fig. 3-4. Examples of airport architectural designs 

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a) source: http://www.public-domain-image.com/full-image/peoplepublic-domain-images-pictures/crowd-public-domain-imagespictures/airport-security-lines.jpg-copyright-friendly-image.html, in 

the public domain, Author: Kitt Hodsden 

b) Palma de Mallorca Airport
 

source: http://www.flickr.com/photos/kalleboo/3536493996/, free
 

to share and remix with the attribution of the work to Karl Baron
 

Fig. 3-5. Examples of impacts of the security "chronic" condition in airports 

The only way to address such concerns is to build into the PBFPD process a mechanism for not only looking at 

expected normal operations (chronic use) but for triggering reassessment if certain operational schemes are 

modified by the building in use. While PBFPD processes like that from SFPE tries to address this by having the 

FPE identify bounding conditions and to develop an Operations Manual, it is not clear from my review that 

these mechanisms are being utilized as intended (cf. previous chapter of this dissertation). 

3.2.3 Fire safety objectives competing with "chronic" objectives evolving over very long period of time 

As another example, consider how the design of hospitals 30 years ago assumed one set of chronic objectives, 

for which specific measures were designed to address fire events, and how internal changes to the hospitals may 

negate the benefit of those fire protection measures. Starting in the 1850's, based on Florence Nightingales' 

"Notes on Hospital", hospital wards were designed as large, open, well-lit facilities so that nurses could 

supervise a lot of patients [15]. As illustrated in Fig. 3-6(a), the "chronic" objective at that time was nurse and 

staff efficiency. Later, patient privacy and comfort became the primary concerns and the "Nightingale" ward 

design was replaced by a series of patient rooms (Fig. 3-6(b)) [16]. 

Looking at these two configurations from a fire safety point of view, the following comments can be made: in 

an open patient ward, staff is present and can detect a fire (or any agitated patient) as soon as possible and may 

extinguish the fire before it spreads away from the 1st burning item. In case the fire is not detected and 

controlled that quickly, smoke and fire may spread fast and evacuation of all ward patients becomes vital. In the 

private patient room configuration, fire detection would rely on automatic detection rather than detection by 

staff who are only briefly present in each patient room. An automatic suppression system could also prevent the 

patients in the room from being injured and a door closing upon fire detection could limit smoke and fire spread 

outside of the room of fire origin. This example clearly illustrates that the design of the system is highly 

45 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

dependent of its "chronic" objectives, which design has a strong impact on how the fire protection measures 

should be designed, installed and maintained as a whole as these measures both include managerial and 

technical measures, prevention and protection measures. More detailed "chronic" objectives related to hospitals 

can be found in [17]. 

a) source: http://www.flickr.com/photos/vculibraries/4269022763/, 

free to share and remix with the attribution of the work to Virginia 

Commonwealth University Libraries 

b) source: http://www.flickr.com/photos/usnavy/5913486058/, free 

to share and remix with the attribution of the work to Official U.S. 

Navy Imagery 

Fig. 3-6. Examples of a) well lit facility ("Nightingale" ward), b) private patient room in a hospital 

3.2.4 Fire safety objectives competing with "chronic" objectives evolving over short or long periods of time 

A "building-occupant" system is dynamically defined with time. A convention center is a typical example of 

such a system characteristic: the structure of the building remains the same in the lifespan of the building but 

the interior configuration constantly changes as a function of the exhibitions proposed by the convention center. 

From a FPE perspective, nature, amount and location of fire loads are very different for a comic convention, 

boat show, sport event, etc. Distributions of attendee characteristics (e.g. age, gender) are also relevant and 

should therefore be gathered and their consequences considered in the fire risk evaluation analyzed by the FPE. 

Looking at turnover rates of building materials and their impact on the environment, Wærp and Holthe [18] 

notably conducted surveys and interviews of property managers and architects in Norway. The following 

paragraph is extracted from their paper: 

“The architects were asked which materials that are often replaced in buildings. This is dependent on 

type of building and year of construction of the building. In office building interior materials is often 

changed e.g. flooring materials, ceilings, interior walls and lightening are all changed within 5-15 years. 

Buildings that are refurbished today are from 1970-80. Solutions and materials are in general poor. There 

are necessary to change ventilation. After 25 years you are left with façade (when quality is good), 

stairway and load bearing structure. In building from about 1900 more components are kept: e.g. doors, 

windows, ceilings, facades and often original interior materials. New buildings from today will probably 

46 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

have better quality than in the 1970-80, but there will probably be frequently change in surface 

materials”. 

This information illustrates the fact that even if a building remains an office building during its whole lifespan, 

the nature and the amount of material (including combustible materials) as well as the exit pathways (interior 

separation may change or completely disappear with "open space" configurations) have to be reassessed 

periodically to verify that the performance of the system regarding fire safety has not decrease. 

It should be noted that building occupant demographics also evolve over long period of times, which may have 

a significant impact on emergency situations. For example, fire evacuation parameters such as walking speed 

and crowd density, established from experiments in the late 1980's, should take into consideration population 

obesity increase. Global ageing population should also be considered [19]. 

The "building-occupant" system can be stable over its life (i.e. a shopping mall would remain a shopping mall) 

but the nature of the individual shops inside may vary in time. Fluctuations can also be seen in the 

characteristics of this system concerning the population number and repartitions during the day (food court 

being more populated around meal times) and days of the week. Transitory combustibles can be located in the 

common areas (outside the mall shops) for more or less extensive periods of time (e.g. Christmas decorations in 

Fig. 3-7). It is necessary to consider of all these fluctuations when assessing fire protection system performance 

(e.g., sprinkler efficiency and combustible control, for this shopping mall example). 

Fig. 3-7. Christmas tree located close to exit routes and main entrance of a shopping mall 

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The "building-occupant" system also "reacts" when new components are introduced inside. Introduction of new 

components, used for "chronic" objectives, may have an influence on the fire risk, because of their own 

hazardous properties. This situation is reviewed by the FPEs when analyzing fire hazards, and it is even quickly 

integrated into standards and good practices when the introduction of the hazardous components is anticipated. 

Following are two examples: 

- In health care facilities, alcohol-based hand-rub solutions have been found to be more effective for standard 

hand washing or hand antisepsis by health care workers than soap or antimicrobial soaps. Placing 

dispensers of alcohol-based solutions in corridors and suites of rooms is expected to decrease the estimated 

more than 88,000 patient deaths attributed to US hospital-acquired infections [20]. It should be noted that 

there is an estimated single annual death in hospital or hospice facility [21]. In other terms, numerous 

combustible liquid sources were added to reach a new "chronic" state, in order to decrease the risk for 

hospital patients to suffer from nosocomial diseases. This change in the "chronic" state of the system has 

been already analyzed by the National Fire Protection Association (NFPA) which integrated it into their 

Life Safety Code, NFPA 101 [22]. The point is that if analysis of a new hazardous material introduced in 

the system is carried out by the FPE, analysis of a new fire protection measure into the "building-occupant" 

system also needs to be carried out, especially if this measure is a managerial one. This is illustrated by the 

second example below. 

- Also in the health care facilities, O'Connor [23] indicated that for these facilities which established smokefree environment / no smoking policies, it was observed that visitors were giving smoking materials to 

patients and residents without the health care staff’s knowledge and that this system adaptation was found 

to explain why this type of ignition source was not decreasing in the corresponding fire statistics. 

3.2.5 Impact of "chronic" objectives in performing the risk analysis related to disruptive events 

Knowledge of the "chronic" objectives is also important when estimating how long building occupants delay 

their evacuation after an alarm starts. In case of a fire, the estimation of this "pre-movement" time is related to 

several factors, and particularly to two called "commitment" and "focus". In Fig. 3-8, people seem quite focus 

on playing slot machines, inside a Japanese game center. The row of slot machines is itself designed to 

maximize occupancy time by a single person whom is provided with a chair, has repetitive actions to perform in 

a very focused vision range, with people in the near proximity, which make it very easy to lose track of time 

and difficult to be aware of anything happening in the surroundings. People are committed to go on playing as 

long as they have still money to feed the machines. The "chronic" objective of these games centers (as well as 

of western casinos), related to a high degree of focus and commitment, leads to an increase of the "premovement" time, and therefore competes with the life safety objectives to have all these people evacuate as 

soon as possible in case of emergency. 

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(source: http://www.flickr.com/photos/davidooms/2964039286/, free to share and remix with the attribution of the work to David Ooms) 

Fig. 3-8. Example of commitment in a Japanese game center 

It should be noted that in case of an emergency many building users have a strong tendency to try to leave via 

the route that they entered by rather than using the nearest exit [24]. Displays in department stores and shopping 

malls are designed to make the potential buyer go from one stand or shop to another: the position of the 

displays, always changing, can also have some influence on the movement time as people need to find their way 

out. Estimation of egress paths would be much different when considering design floor layout empty of the 

movable booths and the real layouts during Sales periods (Fig. 3-9). Besides, lots of additional "Sale" signs may 

also make it more difficult to locate Exit signs. In consequence, during Sales periods, the use of exits other than 

the one people used to enter the department store might be lower than in regular store usage. 

(source: http://fr.wikipedia.org/wiki/Fichier:Ambience_de_solde.jpg, put into public domain by Wikimedia Commons User Medjaï) 

Fig. 3-9. Example of a French department store display during sales 

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3.3	 Theoretical treatment of disruptive events affecting the performance of "buildingoccupant" systems 

3.3.1 Fire is one disruptive event among others which may be "covered" by a contingency plan 

For some types of building occupancies, a contingency plan is elaborated to ensure the safety of the building 

occupants and minimize the recovery period in the event of an emergency (fire, power or communications 

blackout, tornado, hurricane, flood, earthquake, civil disturbance, etc.). These plans mainly concerns 

installations of Performance Group IV, according to the ICC PC classification [11]: such as hospitals or 

designated earthquake, hurricane and other emergency shelters. They describe the actions of the building 

personnel to be performed for different scenarios. For example, the contingency plan of a hospital may contain 

information related to a fire or the loss of HVAC system by a fire. Examination of these contingency plans is 

needed to verify that the emergency actions are coherent with the ones elaborated by a PBFPD process. 

3.3.2 PBFPD processes must examine the actions and events of the recovery phase following a fire 

The actions required in the recovery phase need specific documentation to insure that the system components 

related not only to fire safety but all other components used by the system, are back in full operational mode. 

This specific need is illustrated by the fires that successively occurred in a New Orleans warehouse (Louisiana, 

USA), on March 21, 1996. Based on the information collected in the NFPA investigation report [25], the uncompartmented warehouse contained a combination of high racks (equipped with in-rack sprinklers) and low 

racks (not all with in-rack sprinklers). A first arson type fire successively started in a low rack section 

unprotected by in-rack sprinklers, was detected by staff who unsuccessfully tried to extinguish it, activated one 

over-head sprinkler which action did not extinguish nor control the fire, and eventually was declared out by the 

fire fighters, about 5 hours after they arrived on site. At that point, "once fire control had been achieved, all of 

the sprinkler systems in the facility were manually shut down by closing the individual OS&Y valves on the 

risers", as a result of the opening of numerous sprinkler heads throughout the warehouse, causing extensive 

water damage. Without evaluating the damage to the electrical system caused by water, the electric service of 

the building was restored, starting the second fire, in a high rack storage area, by ignition of combustible 

materials with arcing of damage wiring in this area. "As soon as the second fire was discovered, facility 

personnel began opening the OS&Y valves on the ceiling and in-rack sprinkler systems. However, because 

these systems were impaired during the initial stages of the second fire, they were overwhelmed". This time, the 

fire destroyed all the contents of the warehouse and collapsed the structure. The second fire was declared out 

several days after the fire fighters arrived a second time on site. 

This fire event illustrates the importance of the actions to be performed and the needed documentation (as 

procedures or check-lists) in the recovery period, after the fire is extinguished. These actions not only concerned 

the impaired fire protection system but also one utility system to the warehouse, i.e. electricity. The authors of 

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the investigation report [25] advocated for a utility restoration in a "planned and coordinated manner, and only 

after a complete survey of the damage has been taken" so "that everyone involved with the overhaul and 

restoration operations be aware of what actions are being taken by the different agencies and services involved". 

Nevertheless, they "were unable to identify any reference in an NFPA standard, code, or recommended practice 

that addressed the issue of restoration of utilities and how it should be handled following an emergency". 

After reviewing current PBFPD processes, I found them quite focused on the fire development itself, from 

ignition to extinguishment so that they ignore the recovery phase, which is essential to consider for the system 

as demonstrated by the New Orleans warehouse consecutive fires. 

3.3.3 Specific interconnections may exist between different types of targets or between a target and a 

building component, so a fire can have a direct or an indirect impact on targets 

In some systems, building occupants and building systems may have strong interconnections: in a hospital, 

people can be connected to life supporting machines, so fires impacting these machines (directly or indirectly) 

can affect the life safety of the people connected to them. Indirect effects of a fire on such patients could result 

from a fire damaging the distribution of electricity in the building, as well as the backup of this utility. 

Also in a hospital, a HVAC/filtration system provides air quality and control of microbe and odor migration 

between the different functional zones of the hospital. Scott [13] studied a smoldering fire that happened in a 

storage room in a hospital in New Zealand, in 2008. Smoke generated by this fire traveled via a HVAC duct 

from the storage room to an operating room. This situation can be qualified as a direct impact of the fire, 

because the fire effluents directly affect the safety of the patient and of the medical staff (even if the room 

where the fire was located was not the same room where the targets were located). Keeping the same 

configuration, the HVAC/filtration system provides microbe migration control by maintaining a pressure 

differential between different functional zones: this P assures that microbes are not going from the 

examination room towards the operating rooms where people are more vulnerable to this threat. A fire 

damaging the HVAC system ability to maintain this P would compromise the safety of the patients most 

vulnerable to infections. Thus, this last example also illustrates the indirect effects of a fire on targets. 

In healthcare facilities, the main safety targets are the patients. Losing a building component from a fire may 

affect patients. In other terms, the safety of the patient may depend on the safety of a building component. The 

opposite configuration also exists in some building occupancies. The most emblematic example of this 

configuration is the nuclear power plant, where staff may be in relative danger in case of a fire but have to 

remain within the plant in order to maintain the nuclear core within a safety range. 

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3.4	 Practical treatment of disruptive events affecting the performance of "buildingoccupant" systems 

Within my "building-occupant" system paradigm, I established a risk-informed performance-based process 

which could be applied to quantify the effects of any type of disruptive events affecting the overall performance 

of a specific system. 

At the initial step of the process illustrated in Fig. 3-10, the stakeholders of a considered "building-occupant" 

system clearly indicate the nature and the characteristics of the system in terms of "chronic" objectives. This 

step is essential as it specify the parameters of the "building-occupant" system to be examined in terms of 

building components, occupants and functional/support zones used by the system in order to achieve the 

"chronic" objectives. 

This initial step is also a "political" step of the risk-informed performance-based process as the system 

stakeholders need to come to an agreement on the system main goals and decide whether the system will 

possess specific building attributes such as an atrium or a high rise configuration. 

Technical steps of the overall system performance-based process 

Target 

vulnerability 

criteria 

estimation 

Disruptive 

event risk 

analysis 

(quantification 

of the impact) 

Cost-benefit 

analysis 

Disruptive event 

risk 

characterization 

Disruptive 

event risk 

analysis 

(quantification 

of the 

likelihood) 

Evaluation of 

the integration 

of the 

disruptive 

event 

protection 

measures in 

the system 

Political 

Stakeholders’ 

project 

definition 

Political 

Stakeholders’ 

decision 

Fig. 3-10. Political and technical steps of the system specific risk-informed performance-based process 

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All the information gathered by the stakeholders is then transmitted to the engineer in charge of evaluating the 

impact of a certain type of disruptive event on the overall performance of the system: FPEs to deal with fires, 

structural engineers for earthquakes, etc. Since the system targets are the components which contribute to the 

overall performance of the "building-occupant" system, it is imperative that the stakeholders list in this step of 

the process all the system targets so that the engineer take them into consideration while performing the 

technical steps of the process. 

At this point, the corresponding engineer carries out the "technical" part of the process, which mainly consists 

of a target oriented risk analysis, by performing the steps as follows: 

- selecting risk acceptance metrics that are representative of the considered system in relation to the 

stakeholders' listed targets during the chronic use of the building. The aim of the "risk characterization" 

step is to correlate the likelihood of the disruptive events which occur during chronic operation with 

vulnerability criteria for each of the listed target (e.g. assessing how often the disruptive event causes 

injuries or casualties when the target is the building occupant, based on statistics and past events) - Step 1; 

- quantifying the vulnerability criteria for each target in case of the disruptive event (e.g. evaluating the 

mechanisms by which the disruptive event can have direct and indirect effects on each listed target while 

taking into consideration the capacity/incapacity of the target to absorb the damage from the disruptive 

event and still be functional/loses its functionality) - Step 2; 

- carrying out a risk analysis of the effects of the disruptive event on the overall performance of the system, 

via the characterization of both the likelihood - Step 3 and the impact - Step 4 of the disruptive event on 

each of the listed targets; 

- evaluating the integration of the protection measures against the disruptive event, analyzed in the risk 

analysis, so to verify that these measures, once installed, would not be ignored or misused by the system 

end users - Step 5; 

- performing a cost-benefit analysis of the protection measures against the disruptive event, analyzed in the 

risk analysis - Step 6. 

At the end of the technical steps of the performance-based process, the engineer dealing with a certain type of
 

disruptive event will transmit three important documents (or three components of a consolidated document)
 

back to the system stakeholders:
 

- one document containing the results of the disruptive event risk analysis (from technical Step 3 and Step 4)
 

including a risk matrix or risk curves and explaining how the engineer's proposed protection measures 

reduce the risk of the disruptive event affecting the performance of the studied system, 

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- one document describing the possible interactions of the protection measures designed by the engineer 

against the disruptive event and the other components of the studied system, 

- one document estimating the costs and the benefits to install and maintain the proposed protection 

measures. 

Based on the results of the technical steps of the system performance-based process, the stakeholders finally 

decide on the set of protection measures they want to be installed in the system, knowing how well these 

protections would help the system to mitigate the impact of the disruptive events on the performance of the 

"building-occupant" system in its chronic state, how well these protections would be integrated in the system 

and how much they would cost to install and maintain. 

In case the performance-based process is simultaneously conducted on several disruptive events, the different 

engineers involved in proposing protection measures against their respective disruptive events have to generate 

a common additional document since it is important to verify that all their additional protection measures are 

not counterproductive (Fig. 3-11). It should be noted that the initial political step is identical for the 

stakeholders as they only need to provide once, in their own terms, the specifics of their "building-occupant" 

system. The "translation", in terms of solving the right problem for each disruptive event, is made by the 

corresponding engineer in the technical step related to risk characterization. 

Fig. 3-11. Practical treatment of multiple disruptive events 

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3.5 Conclusions of this chapter 

Designing a building project is a complex enterprise involving project stakeholders who are the main drivers of 

the project concept and professional groups who are the main drivers of the actual realization of the project. In 

addition to this complexity, differences arise between the building project at its design phase and when the 

building is actually exploited by its end users. 

The performance of a building depends on the interrelations between the different components of the building 

which are separately designed by specific engineers, having their own objectives to fulfill, so the final 

integration of all the building components may not be optimal. When these components concern disruptive 

events, i.e. events affecting the daily performance of the building such as fires, it was found that the end users 

might misuse or ignore the protection measures against the disruptive events, because these measures were not 

integrated well enough by the end users. 

This chapter presented the outcomes of research carried out in order to: 

- define a paradigm of study organized around systems formed by specific building types and their associated 

occupants so to clearly determine how hazardous disruptive events such as fires affect these system daily 

performance, 

- introduce a corresponding system specific risk-informed performance-based design process, which could 

take into consideration the complexity of such systems and their evolution during disruptive events. 

References 

1.	 Zalejska-Jonsson A. Evaluation of low-energy and conventional residential buildings from occupants' perspective. 

Building and Environment 58 (2012) 135-144 

2.	 International Council for Research and Innovation in Buildings and Construction. Performance Criteria of Buildings for 

Heath and Comfort. Report CIB number 292, prepared by ISIAZ-CIB Task Group TG 42. 2004 

3.	 SFPE Engineering guide to Performance-Based Fire Protection - Second Edition, 2007 

4.	 SEAOC, Performance-Based Seismic Engineering of Buildings, Volume I, Structural Engineers Association of 

California, April 3, 1995 

5.	 Ornstein SW et al. Performance evaluation of a psychiatric facility in Sao Paulo. Facilities 27, 3/4 (2008) 152-167 

6.	 Spekkink D. Performance Based Design of Buildings - PeBBu Domain 3 - Final Domain Report - Performance Based 

Buidling Network (PeBBu) October 2005 (availabe at: 

http://www.pebbu.nl/resources/allreports/downloads/07_D3_FinalReport.pdf, checked 10/31/2012) 

7.	 Sheffi Y. The Resilient Enterprise, Massachusetts Institute of Technology Press. 2005 

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8.	 Knight RF and Pretty DJ. The Impact of Catastrophes on Shareholder Value, The Oxford Executive Research 

Briefings. Templeton College, University of Oxford, England 

9.	 International Code Council (ICC) International Building Code, 2012 

10.	 Lataille JI. Factors in Performance-Based Design of Facility Fire Protection. Fire Protection Engineering, 2nd quarter 

2008, Society of Fire Protection Engineers, 2008 (available at: http://magazine.sfpe.org/fire-protection-design/factorsperformance-based-design-facility-fire-protection, checked 10/31/2012) 

11.	 International Code Council (ICC) Performance Code, 2012 

12.	 US Department of Commerce, Bureau of Census, North American Industry Classification System (NAICS) 

Definitions. 2007 (available at: http://www.census.gov/eos/www/naics/2007NAICS/2007_Definition_File.pdf, checked 

10/31/2012) 

13.	 Scott D. Fire in an operating Theatre – What really Happened? – A Case Study of a Fire in a Private Hospital in 

Hamilton, New Zealand. Proceedings of the 4th International Symposium on Human Behaviour in Fire 2009, pp. 313­

322 

14.	 (ABCB) Australian Building Codes Board. International Fire Engineering Guidelines, 2005 edition 

15.	 Richardson R. Florence Nightingale and hospital design. King's College, London. 2010 (available at: 

http://www.kingscollections.org/exhibitions/specialcollections/nightingale-and-hospital-design/florence-nightingaleand-hospital-design, checked 10/31/2012) 

16.	 Tolley M. Institutional Buildings, the Built Environment – Public Spaces. 2011 (available at: 

http://martintolley.com/environment/BuiltEnv2EnvPsy6.html, checked 10/31/2012) 

17.	 Alvarez A. and Meacham B.J., Towards an Integrated Performance-Based Design Approach for Life Safety Across 

Different Building Use Groups, in: Proceedings of the 12th International Interflam Conference, Nottingham, UK, 2010 

18.	 Wærp S. and Holthe K. Turnover Rate and Environmental Load for Building Materials – Checkpoints in Design 

Process. CIB14251, SINTEF. 2009 (available at: 

http://www.sintef.info/upload/Byggforsk/Bibliotek/Publikasjonsdatabasen/CIB14251.pdf, checked 10/31/2012) 

19.	 Spearpoint M and MacLennan HA. The effect of an ageing and less fit population on the ability of people to egress 

buildings. Safety Science, vol. 50, issue 8,1675-1684, October 2012 

20.	 (NFPA) National Fire Protection Association. NFPA 101 Life Safety Code® Handbook, eleventh edition, edited by R. 

Coté and G. E. Harrington, NFPA, pp.667-669. 2009 

21.	 Flynn J.D. Structure Fires in Medical, Mental Health, and Substance Abuse Facilities, February 2009, National Fire 

Protection Association. 2009 

22.	 (NFPA) National Fire Protection Association. NFPA 101 Life Safety Code® 2009 edition, NFPA. 2009 

23.	 O’Connor D.J. Health care occupancies, chapter 15, section 20 of the 20th edition of the Fire Protection Handbook, 

National Fire Protection Association, 2008 

24.	 Kobes M. et al. Way finding during fire evacuation; an analysis of unannounced fire drills in a hotel at night. Building 

and Environment 45 (2010) 537-548 

25.	 Comeau E. and Puchovsky M. NFPA Fire investigation report, Warehouse fire, New Orleans, Louisiana, March 21, 

1996, National Fire Protection Association. 1996 

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4.	 A FRAMEWORK FOR RISK-INFORMED PERFORMANCE-BASED FIRE 

PROTECTION DESIGN FOR THE BUILT ENVIRONMENT 

Twenty years of experience with performance-based fire protection design (PBFPD) was reviewed and I 

determined that shortcomings and challenges still need to be addressed in order to expand the application of 

PBFPD processes as an option to the prescriptive requirements imposed by building regulations (cf. Chapter 2 

of this dissertation). Existing guidance related to these processes has been found to be too generic, meaning that 

fire protection engineers (FPEs) are required to significantly expand upon the information provided by this 

guidance when applying it to their specific projects resulting in wide variation in practice. Furthermore, the 

application of these processes requires the agreement by all of the involved stakeholders regarding key elements 

of these processes, such as the definition of the performance criteria and the selection of the fire design 

scenarios against which the trial designs would be evaluated: issues upon which stakeholders have to expertise. 

Given these findings, I conducted research aimed to ultimately lead to the establishment of more specific 

guidance for PBFPD, which provides more specific technical guidance and which incorporates a new process 

separating the ‘political’ decisions taken by the stakeholders from the ‘technical’ analysis to be performed by 

the FPEs. 

One important initial finding of my research was that the generic characteristics of the current PBFPD processes 

could be attenuated when establishing guidance for specific building use groups and for specific objectives (e.g. 

life safety, business continuity, heritage preservation) [1]. 

In addition, my research indicated that current PBFPD processes are, on one hand too fire focused, and on the 

other hand too centered on the design of fire protection measures, leading to the possibility that fire protection 

measures deemed appropriate at the time of design might not be the most appropriate when implemented in a 

building, as key aspects of the fire protection design might be ignored or worse "rejected" by the occupants of 

the building when needed the most, since fire is not a daily concern [1]. 

A risk informed performance-based design process was then established in order to assess the overall 

performance of systems formed by specific building types and their associated occupants in case of disruptive 

events, such as fire, natural hazards, and economic crisis, affecting these systems (cf. Chapter 3 of this 

dissertation). 

This chapter presents the application of this system specific risk-informed performance-based design process 

for the treatment of fire events, and how it differs from the current PBPFD processes, notably by providing a 

level of detail that is lacking in current PBFPD processes and by clearly separating the political steps from the 

technical ones, leaving the FPEs with a straightforward independent technical part. 

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I estimate that a successful implementation of the new system performance-based design process for the 

treatment of fire events will require acceptance, by the FPE community and the involved stakeholders, of the 

need for a paradigm shift from one in which fire is the center of the problem to one in which building 

performance metrics are evaluated in the case of fire events. 

4.1 Challenges of the current PBFPD processes: the need to be more specific 

It was found that there are complications with respect to application of the current PBFPD approaches from a 

regulatory perspective. While existing PBFPD approaches focus on fire and fire systems, they are very generic 

in how they do so, not specifying what scenarios to consider, how to characterize design fire, for which 

occupant attributes, and so forth. To a certain extent, such flexibility was targeted due to (a) the wide range of 

building considerations for which the PBFPD approach might be used, and (b) because specifics of design fires 

and acceptance criteria can be considered public policy decisions, not engineering decisions, as they help define 

tolerable levels of performance or risk. While such flexibility works well for engineers, it did not sit well with 

regulatory officials, since there was no clear way to determine ‘good’ designs. As a result, wide variation 

existed in developed designs, and in order to lessen the variation, some countries have now moved to 

‘prescribe’ certain performance factors, such as scenarios, fires and criteria. While this is in some ways helpful, 

it also misses aspects of importance that need to be addressed. However, it helps highlight the need to separate 

‘political’ decisions from ‘technical’ ones. 

There are many more challenges for fire protection engineers created by the current PBFPD processes being too 

generic, which have been identified and detailed in Chapter 2 of this dissertation. For the purpose of this 

chapter, they can be characterized as: 

1.	 Applying generic guidance to specific projects, often times lacking the detail necessary for comprehensive 

analyses, which may result in important fire performance concerns being missed. 

2.	 Defining, using and quantifying the performance/acceptance criteria, which should be determined by policy 

makers and decision makers (AHJs), not by the FPEs. 

3.	 Selecting fire design scenarios to test fire protection systems rather than to test building fire safety 

performance. 

4.	 Comparing the levels of performance between an engineering solution and the one based on prescriptive 

requirements without have a good basis of comparison. 

5.	 Having insufficient guidance to determine the most influential factors affecting the evaluation of trial 

designs. 

6.	 Assuming "idealized" performance of fire protection measures (i.e., condition at time of design, omitting 

users) as compared with "real life" performance of installed measures over time, as impacted by occupant, 

and as otherwise impacted, 

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7.	 Estimating the consequences of fire design scenarios on building performance without having the whole 

performance picture adequately defined. 

8.	 Resorting to adapting literature values, when available, to use in models, rather than being forced to 

demonstrate the values are appropriate and/or utilize appropriate values. 

As intimated in (2) above, there has to be a clear understanding of both technical and political issues, as several 

decisions in the PBFPD process are dependent on policy makers and decision makers (e.g., performance criteria 

and design fire scenarios have to be agreed upon by the considered stakeholders before the fire protection 

engineer can really start the technical part of the process). As such, it would be extremely beneficial for the 

PBFPD process to clearly delineate ‘political’ (joint) decisions from ‘technical’ ones, making the engineering 

tasks more straightforward to address. 

4.2	 Shifting the paradigm: studying how a global system formed by a building and its 

occupants reacts when a fire can occur 

While the "fire protection systems" approach makes sense in retrospect, given the somewhat uncoordinated 

development of the PBFPD idea, process, tools for analysis, data and so forth, it meant that fire in the context of 

overall building performance has not necessarily been analyzed sufficiently. When I investigated building fire 

protection designs that were developed using this approach, I found that FPEs only consider the characteristics 

of a building and of its occupants only into the PBFPD process as parameters of the fire design scenarios and in 

the development and evaluation of fire protection measures. This consideration taking place during the design 

phase of a building project led to a "disconnect" between the fire protection components and the context of the 

building in use: FPEs expected that the fire protection measures would be correctly designed and maintained so 

they would operate as intended, as an independent component of the system formed by the building and its 

occupants. Unfortunately, this was found not to be the case. In numerous instances, investigation reports of fire 

events reflected how the interaction between the building, fire and occupants influence each other during 

events. For example, a warehouse which suffered small damage after a first fire controlled by an automatic 

sprinkler system was completely destroyed by a second fire some hours later as the sprinkler system was shut 

off due to some water damage caused by the opening of numerous sprinkler heads throughout the 

warehouse [2]. 

The photographs below (Fig. 4-1) were taken in a conference center. One fire exit sign is practically hidden 

behind the black signage. Even if delegates find the fire exit sign, they would probably use the double door to a 

conference room (that they probably use to go during the conference), instead of getting through the fire exit 

door located at the right end of the corridor, almost hidden by the blue panel. 

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a) view from a corridor of a conference center b) Fire exit door in the corridor side, mostly hidden 

by the blue panel and "competing" with the usual 

delegate path to go through the double door to a 

conference room 

Fig. 4-1. Fire exit way finding problematic in a conference center 

These illustrative examples made us consider that the study of the fire protection measures (technical systems 

and managerial procedures) could not be done without considering the system they are installed in. Indeed, on 

one hand, these measures involve the building occupants (during the evacuation process) for whom fire is a 

"disruptive" event during the otherwise normal building use. On the other hand, they are not completely 

independent from the other building parts as they deal with a lot of common space (e.g., rooms delimited by 

doors, corridors, atrium). 

As a result, I needed to define a global system in which fire protection measures would be one component, 

among may, and then verify how shifting the paradigm of study to this system would prevent the fire protection 

component from being ignored (conference center example) or even worse rejected (warehouse example) by the 

occupants of the building when a fire occurs. 

In addition, it should be noted that researchers have only recently started to incorporate building interior design 

in their models due to the complexity of simulating these details, as well as the needed time and resources to run 

the corresponding simulations. For example, Stern-Gottfried and Rein [3] looked at how building interior design 

influences fire spread in large, open-plan compartments while Oven and Cakici [4] examined how this building 

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interior design influences the evacuation process during emergencies, as obstacles increase travel distances and 

create bottlenecks. Thus, fire researchers also realize the effects of the building use on the fire and the fire 

evacuation process and are developing tools to assess these effects. Back on the engineering side, by shifting the 

paradigm, I estimate that FPEs will incorporate the results of the fundamental fire research more easily and 

more quickly into their safety analyses. 

4.3	 Application of the system performance-based process to fire disruptive events: 

Creating a new PBFPD process 

One challenge previously identified in this dissertation concerns the relationship between the technical aspect 

and the political aspect of the current PBFPD processes. By shifting the current fire centered paradigm 

associated with these processes to a paradigm centered on the study of a "building-occupant" system, the 

performance of the system can be assessed when this system is affected by any kind of disruptive events 

(technological hazard, natural hazard, economical hazard...) as presented in Chapter 3 of this dissertation. 

In my "building-occupant" system paradigm, I defined several key concepts in the previous chapter. These 

concepts are summarized as follows: 

“Targets” are the system agents responsible for the system daily performance (building occupants and 

components). During normal every day conditions or "chronic states of the system", they are located in 

"functional zones" where they carry out their activities associated with "chronic objectives", established in 

accordance with the system scope and performance. "Utility zones" include system support components such as 

electricity, HVAC and plumbing. "Disruptive events", such as fires, have to be considered between two 

consecutive "chronic states". In order to mitigate the "event effects" on the system performance, "acute 

objectives" have to be set up so to take into consideration "direct effects" and "indirect effects" with which the 

disruptive events can possibly damage the targets. 

Detailed information about the "building-occupant" system paradigm and the system performance-based 

process are presented in the previous chapter of this dissertation. The application of this process to a fire 

disruptive event is presented in Fig. 4-2. Each step of the process will be explained in the subsequent parts of 

this chapter. 

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Political 

Stakeholders’ 

project 

definition 

Technical steps of the new PBFPD process 

Target 

vulnerability 

criteria 

estimation 

Fire risk 

analysis 

(quantification 

of the impact) 

Cost-benefit 

analysis 

Risk 

characterization 

Fire risk 

analysis 

(quantification 

of the 

likelihood) 

Evaluation of 

the integration 

of the fire 

protection 

measures in 

the system 

Political 

Stakeholders’ 

decision 

Fig. 4-2. Application of the system performance-based process to a fire disruptive event 

The following section shows how the system performance-based process is applied in the case of the disruptive 

events being fires and how different this new PBFPD process is from the current ones. 

4.3.1 The new PBPFD process is a target oriented process within the "building-occupant" system paradigm 

The new process separates the political aspect from the technical one, concentrating the political aspect at the 

very start and the very end of the PBFPD process, leaving the technical aspect clearly within the realm of the 

FPE. Again, the political process includes regulated issues as well as stakeholder decisions. The principle of this 

separation is illustrated in Fig. 4-2. 

- At the start of the PBFPD process, the stakeholders define the project and present all of the characteristics 

of the "building-occupant" system to be examined: building parameters, occupant parameters and 

functional/support zones used every day by the system. The stakeholders still have to agree on the main 

goals and objectives related to the considered "building-occupant" system and precisely what specific 

building attributes are of concern (e.g., atrium, high rise configuration...). These are considered political 

aspects of the problem, as decisions are required by others than the FPE alone. Once decided, all of this 

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information is transmitted to the FPE who starts the technical aspect of the PBFPD process by selecting risk 

acceptance metrics that corresponds to the considered project; 

- After performing the technical steps of the PBFPD process, the fire protection engineer will give three 

important documents back to the stakeholders: 

- one document containing the results of the fire risk analysis (from Step 3 and Step 4) including a risk 

matrix or fire risk curves and how the selected fire protection measures reduce the fire risk for the 

studied system, 

- one document describing the possible interactions of the fire protection measures and the other 

components of the considered "building-occupant" system, 

- one document estimating the costs and the benefits of installing and maintain the proposed fire 

protection measures. 

- based on the three documents provided by the FPEs, the stakeholders have all the information they need to 

take their decision regarding the fire protection measures they want in the studied "building-occupant" 

system, knowing how the overall performance of the system would be affected by fire events. This again is 

a "political" issue, as I consider that it is only the responsibility of the stakeholders to select the fire 

protection measures they will have installed in their systems in association with the loss of system 

performance that they ultimately accept for their system in the case of fire events. 

It should be noted that some feedback is possible between the first technical task of the PBFPD process (risk 

characterization) and the stakeholders' description of the system, as at the beginning of a completely new 

project all the design features may not be available or finally set up, so changes that would influence the PBFPD 

may occur at that stage, implying some information feedback between the stakeholders and the FPE. Feedback 

is also considered concerning the risk characterization in the case the stakeholders have an idea of the level of 

risk they agree to accept. If it is so, this information is also gathered by the FPE as it will help him/her to design 

acceptable trial designs. More concerning this feedback process is presented in section 4.4 of this chapter. 

It should be understood that the new PBFPD process is applied to specific "building-occupant" systems and not 

in a generic way which could be applied to every kind of project. In consequence, the guidelines that the FPEs 

use for a specific project are established for the type of "building-occupant" system the considered project is 

categorized into. This means that in order to apply the technical steps of the new PBFPD process (Fig. 4-3), 

specific guidelines for each of its six steps have to be written for specific and well defined "building-occupant" 

systems. 

63 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 Risk 

characterization 

Target 

vulnerability 

criteria 

estimation 

Fire risk 

analysis 

(quantification 

of the 

likelihood) 

Fire risk 

analysis 

(quantification 

of the impact) 

Evaluation of 

the integration 

of the fire 

protection 

measures in 

the system 

Cost-benefit 

analysis 

Fig. 4-3. Steps to be performed in the technical aspect of the proposed PBFPD process 

Risk characterization is about translating the fire safety engineering problem from a stakeholders' perspective to 

a FPE perspective and to verify that the FPE has considered all the targets and define risk metrics relevant to the 

different targets of the studied system. In the "building-occupant" system paradigm, the problems FPEs have to 

solve are related to the characterization of the impact (in terms of occurrence and intensity) the targets are 

affected with, in case of fire events. 

Then, for each considered targets, the FPE has to quantify how these targets are affected by direct and indirect 

effects of fire events, events involving a fire and defined between two "chronic" states of the system. 

Fire risk analysis has then to be conducted in order to characterize the likelihood and the consequences of fire 

events on the targets. The FPE work is then to propose fire protection measures in order to minimize the 

occurrence of the damaging fires and mitigate the impact of these fire events on the system performance (i.e. the 

consequences of the fires events affecting system targets). 

The next step of the technical process is then to evaluate how the fire protection measures analyzed in the fire 

risk analysis would be integrated into the studied system, in other terms, if they are going to be compatible with 

the components which are used on an everyday basis so they are not counter-productive and therefore ignored 

or worse rejected by the system. This step goes beyond the documentation on how the fire protection measures 

are designed, installed and maintained in the current PBFPD processes. 

The last step of the technical process is for the FPE to perform a cost benefit analysis of the fire protection 

measures established during the fire risk analysis. 

4.3.2 Comparison with the current PBFPD processes 

When examining the portion of the PBFPD process established for example by the Society of Fire Protection 

Engineers [5] presented in Fig. 4-4, one can realize that the influence of the stakeholders remains important all 

along the process, while establishing the design brief, that is to say even before the fire protection engineer 

looks for solution with defining and evaluating trial designs. 

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Define Project Scope 

Steps to elaborate the Design Brief

Define Stakeholder and Design and Design Objectives Objectives 

Influence of the stakeholders and the FPE at each

step of the process 

Identify Goals 

Develop Performance Criteria Performance Criteria 

Develop Design Fire Scenarios 

Develop Trial Designs 

Fig. 4-4.	 Relative influence of the stakeholders and the fire protection engineer in the different steps of the 

elaboration of the design brief according to SFPE guide [5] 

In conclusion, I estimate that the new PBFPD process allows a clear separation between the political aspect and 

the technical aspect of the process, which will bring the benefits for: 

- the stakeholders who will only define the context of their considered system, in terms of their expected 

performance for the system to withstand fire events, and who will consider at the end of the process the 

different options proposed by the FPE based on a fire risk analysis, the evaluation of the integration of the 

fire protection measures into the system and their associated costs and benefits, 

- the fire protection engineer who, after getting all the characteristics of the problem to solve, will conduct 

and independent straightforward engineering analysis and propose his solutions for the stakeholders to 

finally decide. 

At the end of the new PBFPD process, a political decision is taken by the stakeholders based upon a technical 

analysis by the FPE, including results from a fire risk analysis describing how often and deep fire events would 

degrade the overall performance of the system, a document showing how the selected fire protection measures 

would be integrated into the system and a corresponding cost-benefit analysis of these measures. 

65 
66

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The political decision 

is taken by the 

stakeholders based 

upon a technical 

analysis by the FPE 

Target vulnerability 

criteria estimation 

Fire risk analysis 

(quantification of 

the impact) 

Cost-benefit analysis 

Risk 

characterization 

Fire risk analysis 

(quantification of 

the likelihood) 

Evaluation of the 

integration of the fire 

protection measures 

in the system 

Political sphere 

involving making 

decisions 

Technical sphere involving engineering problem solving

Technical independent linear process for the FPE 

NEW 

Stakeholders’ 

decision 

Stakeholders’ 

decision 

Define Project Scope 

Identify goals 

Define Stakeholder 

and Design objectives 

Develop Performance 

Criteria 

Develop Design Fire 

Scenarios 

Develop Trial 

Designs 

Evaluate Trial 

Designs 

Select final design 

Prepare design 

documentation 

Design brief 

Performance-Based 

Design Report 

Specifications, drawings, 

and Operations and 

Maintenance Manual 

Selected Design Meets 

Performance Criteria? 

Modify Design or 

Objectives 

Yes 

No 

The technical solution is 

taken by the FPE based 

upon a political decision 

agreed by the stakeholders 

Political sphere 

involving making 

decisions 

Technical sphere involving

engineering problem solving 

for the FPE 

Technical politically dependent iterative process 

66 

Fig. 4-5. Comparison between the new PBFPD process and the PBFPD process established by SFPE [5] 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

As a consequence of shifting the paradigm from one which is centered on the fire and the fire protection 

measures to one which describes in details the "building-occupant" system and evaluates its performance, a new 

PBFPD process has been developed and the main differences between this new process and the current ones are 

illustrated in Fig. 4-5. The main difference can be summarized by the end products of these two different 

processes: 

4.4	 Proof of concept of the New PBFPD process: closing "Iteration Zero" (verification 

of the usability of the process) 

Now that I have shifted the paradigm from the study of the fire event itself (as in the current PBFPD process) to 

the study of the effects of fire as a disrupting event of a "building-occupant" system and developed a new 

PBFPD process to accommodate this new paradigm, this section presents the proof of concept for this process. 

This proof of concept constitutes "Iteration Zero" of a longer-term goal for the profession: establishment of 

detailed guidelines for each step of the process for all types of systems declared relevant to stakeholders. 

Based on Fig. 4-2, the new PBFPD process is used as follows: 

The different stakeholders define the characteristics of the project under consideration or review. Context about 

the use of the "building-occupant" system is detailed in order to assess the importance of this system inside a 

system network. Targets are defined by the stakeholders, as well as functional zones and other relevant 

information on how the system performs on a daily basis (interconnections between functional zones, utility 

systems, relations between building occupants and building systems...). Eventual contingency plans are given 

to the FPE. Metrics related to the goals and objectives agreed among the involved stakeholders are then defined 

in order to assess the proper parameters or targets of the system's performance. 

At this stage of the PBFPD process, stakeholders may or may not have a preconceived estimation of their 

required levels of performance for the considered system. If not, the performance metrics characterizing each of 

their goals and objectives are used by the FPE to conduct the technical part of the PBFPD process. Fire risk 

curves or matrices are used to translate into the PBFPD process, the performance of the system to withstand fire 

threats, according to how often and how damaging these threats are. This is schematically illustrated in Fig. 4-6. 

67 
 

 

 

 

 

 

 

 

 

 

 

 

Probability 

Gravity 

Class 

1 

Class 

2 

Class 

3 

Class 

4 

Class 

5 

Level 

5 

Level 

4 

Level 

3 

Level 

2 

Level 

1 

Damage metric 

Frequency of thedisruptive event 

Current "chronic" state of the "building-occupant" system, as a baseline of the study of the disruptive event 

Performance metric 

Time 

Fig. 4-6. Translation of fire risk characterization in the "building-occupant" system paradigm 

Since the information related to the fire risk characterization is directly presented as fluctuations of the 

performance of the system, this information can be given back to the stakeholders who can then decide to 

clearly state their performance criteria, as illustrated, as an example, in Fig. 4-7. In this example, for a 

"frequent" disruptive event, the stakeholders allow the performance of the system to be less than the one defined 

in the risk characterization: in other terms, they allow more property loss or a longer recovery time, depending 

on the vulnerability metric. For a "less frequent" disruptive event, the stakeholders allow the performance of the 

system to decrease as the one defined in the risk characterization. For a "rare" disruptive event, the stakeholders 

do not allow the performance of the system to be less than the one defined in the risk characterization. Based on 

their performance requirements, a new fire risk curve can be constructed and fire disruptive events will then be 

assessed by their locations, in terms of (probability-consequences), relative to this new fire risk curve. 

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Performance metric 

Time 

Minimum levels of performance agreed among the stakeholders 

for a frequent, less frequent and rare disruptive event Frequency of the disruptive event 

Damage metric 

Fig. 4-7.	 Translation of the performance requirements of the "building-occupant" system as fire risk 

characterization 

Targets vulnerability metrics are then gathered by the FPE, based on the targets' natures and characteristics. 

Based on the description/information gathered about the system (functional zones, location and characteristics 

of targets...), the FPE performs the fire risk analysis. Event trees are used with zones containing targets and 

most probable fire ignition locations as initiation points of these trees. In conjunction, fault trees are used with 

"affected target" as final/top point, in order to capture the indirect threats to the considered targets. The aim of 

this PBFPD process step is for the FPE to cover fire events that are relevant to the performance of the system, 

that is to say the fire events that could affect the stakeholders' targets and to define fire protection measures or 

safety barriers to prevent these scenarios from occurring, with a frequency estimated on fire ignition frequencies 

and reliability of the considered fire protection measures. At the end of this process step, the benefits of the 

safety barriers, in terms of decreases of fire frequencies and consequences can be gathered in a synthetic form, 

as illustrated in Fig. 4-8. 

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Frequency of thedisruptive event





   

Damage metric 

() no fire protection measures are put in place 

() x fire protection measures are put in place 

() (x+y) fire protection measures are put in place 

Fig. 4-8. Schematic representation of the risk reduction of scenarios of disruptive events 

The next step of the proposed PBFPD process is performed to be sure that the inclusion of fire protection 

measures does not affect the performance of the other system components dedicated to achieve "chronic" 

objectives or other safety objectives. Not only is it verified that inclusion is not counterproductive for the daily 

performance of the system, in short term and in long term, but also that the safety barriers are maintained 

properly. 

The final step of the technical part of the proposed PBFPD process is related to the cost-benefits of the fire 

protection measures. 

At that point, the FPE delivers three important pieces of information to the stakeholders: 

- The schematic representation of the risk reduction of scenarios with the different sets of fire safety barriers, 

as illustrated in Fig. 4-8, with a description of barriers and more details on the most "valuable" barriers, that 

is to say the ones which lower the fire risk the most, 

- The means of verification that the fire safety barriers are not counterproductive for the level of performance 

of the analyzed system, 

- The costs of the installation and maintenance of the different sets of fire safety barriers. 

Based on that information, the stakeholders finally decide what fire protection measures to add as components 

of their system. 

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4.5	 Closing "Iteration Zero" (demonstration of the ability to overcome the challenges 

encountered by the use of the current PBFPD processes) 

Challenges that FPEs, code regulators and authorities having jurisdictions are facing when applying the current 

PBFPD processes are briefly listed in section 4.1 of this chapter and presented in detail in Chapter 2 of this 

dissertation. The following paragraphs are dedicated to demonstrate how the proposed PBFPD process 

overcomes these challenges. 

The main challenge related to the application of generic guidelines has been addressed with the proposed 

elaboration of detailed guidelines designed for specific "building-occupant" systems and with the organization 

of "target oriented" risk analyses. Also, the challenge related to the intricacy of the technical and political 

aspects of the current PBFPD processes is overcome as presented in Fig. 4-2, and detailed in Section 4.3.2 of 

this chapter. 

The following demonstration aims to illustrate, with real fire events or constructed ones, that the proposed 

PBFPD process is more suitable to deal with the specificities of a "building-occupant" system than the current 

ones and therefore it points out where the FPE really needs to focus his/her analysis, what information is 

needed, for what step of the process and why this information matters. This demonstration is organized 

according the different steps of the proposed process. Each example is presented in three parts: the concern, 

how existing approaches fall short, and how my approach addresses the concern. 

4.5.1 Risk acceptance characterization 

Business continuity is often a FP goal but business recovery is not only dependant on the building that is 

analyzed but also on the network of buildings and industry it belongs to (cf. Chapter 3 of this dissertation), so 

establishing parameters of the performance of the analyzed building requires the FPE to look at not only how it 

operates by itself but also at how a disruptive event such a fire can decrease the performance level of the 

network. A "building-occupant" system is a dynamic one as its owner and users can constantly change during 

its life span, affecting how the system is used for, how it is managed and what level of performance is 

associated with it. 

A generic PBFPD process is not as adaptable as a process which has been designed to take these changes into 

consideration as the analysis of the system is at the core of such an oriented process. The information related to 

the system is gathered at the start of the process, because the level of performance is a function of all these 

information, and the quantification of this level of performance is the "only" real engineering problem the FPE 

has to solve. Besides, the same information is needed across all the steps of the proposed process. In the current 

PBFPD processes, information and data are gathered more for the sake of running models than for 

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characterizing what the engineering problem is about. In other terms, the current PBFPD processes were 

elaborated by FPEs for FPEs, incorporating thought processes they were trained to have, which explained why 

the systems analysis they borrowed in the 1970's quickly focused only on fire protection components. This 

independent state of mind still results nowadays in frictions mainly between the FPE and the architect / building 

owner. 

Since the proposed process is integrated into a global system analysis, I assume that its application would tend 

to attenuate these frictions, not only in the design phase but each time the building users modify the 

characteristics of the analyzed system. Thus, the proposed process will also manage the dynamic changes of the 

system as fire disruptive events are characterized with taking into consideration the current "chronic" state of 

the system, as illustrated in Fig. 4-6. 

4.5.2 Target vulnerability criteria estimation 

As discussed in Chapter 2 of this dissertation, the terminology "performance criteria" defined in the current 

PBFPD processes does not apply to the quantification of the overall performance of a "building-occupant" 

system, but it rather corresponds to target conditions when affected by the direct effects of a fire. For example, 

SFPE [5] indicates that "performance criteria generally take the form of damage indicators. It is not necessary 

that the means of preventing at this stage [i.e. when defining them], but a complete understanding of the 

acceptable limits of damage and injury must be well understood. If the engineer develops the performance 

criteria, the damage indicators utilized should come from technical documents and their selection should be 

thoroughly explained and documented for stakeholders". SFPE also indicates that "performance criteria might 

include temperature of materials, gas temperatures, smoke concentration or obscuration levels, 

carboxyhemoglobin (COHb) levels, and radiant flux levels". 

In my "building-occupant" system paradigm described in details in Chapter 3 of this dissertation, these 

"performance criteria" are indeed related to the effects of a fire on a target but they only integrate the fire 

negative input on the targets. In other terms, they do not quantify how the target itself will respond to these fire 

effects (e.g. submitted to the same smoke environment, a bedridden patient after surgery would be endangered 

before a hospital staff member and before a fire fighter). My "target vulnerability criteria" integrate this 

response, as my process is dedicated to the variations of performance of the targets in the case of a fire event, 

not only during the fire itself until these targets recover and reach again a "chronic" state. 

Let us consider people as targets. I found out that life safety criteria currently focus on direct fire effects. 

However, there are other issues. For life safety, the following criteria are not considered in current PBFPD 

processes: criteria related to stampede (e.g. Brooklyn theater fire on December 5, 1876, Iroquois theater 

(Chicago) fire on December 30, 1903, and the much more recent Uphaar Cinema fire, in India on June 13, 

1997) or indirect damage (when people are connected to life supporting machines). Several criteria are absolute 

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values, with no notion of duration attached to it. When assessing the evacuation process, transitory states are not 

taken into consideration in the current approaches, as they do not detail the steps to perform a dynamic analysis 

of both the Available Safe Egress Time (ASET) and the Required Safe Egress Time (RSET). Loss of visibility 

may be transitory, in space (near the fire origin) or in time (until an eventual smoke management unit starts). 

Because the proposed PBFPD process is target oriented, this specific step will include the most exhaustive and 

appropriate list of target vulnerability criteria required to perform the subsequent risk analysis. This is why the 

initial political step of my process is crucial as the stakeholders establish the list of targets (people, building 

content, etc) and describe how the activities of these targets contribute to the overall performance of the system. 

4.5.3 Fire risk analysis (quantification of the likelihood) 

It is intended that shifting the paradigm will also allow a more comprehensive and coherent definition of the 

performance of the "building-occupant" system among the stakeholders and the fire protection engineers. As a 

result, FPEs have to consider the fire problem inside this paradigm where the actors contributing to the 

performance of a system (building occupants and building components) have then to be the subject of a fire risk 

analysis as defined "targets" since fires affecting directly or indirectly these targets would diminish the overall 

performance of the system, which is the main concern of the stakeholders. It should be noted that "functional 

zones" and "utility zones" are concepts that are more accessible and understandable to the stakeholders than 

"fire zones" and "smoke compartments" that are centered about fire scenarios which are not a daily 

preoccupation of the building occupants. In order to fully grasp the impact of fire events and the benefits of 

implementing the system with fire protection measures, the FPEs need to communicate to the stakeholders with 

concepts that they are familiar with and verify that the FPE concepts integrate well with the stakeholders' ones. 

As an example, Fig. 4-9. illustrates the differences of concepts between the "functional zones" in the "buildingoccupant" paradigm and the smoke compartments used by FPEs. In a), three functional zones have been 

established according to the system characteristics. Each functional zone contributes to the daily performance of 

the system. Without knowing this information, a FPE could design two different smoke compartments (in b)) 

according to the current PBFPD processes, resulting in affecting two or three functional zones in case of a fire 

spreading in Smoke Compartment 1 (SC1) or Smoke Compartment 2 (SC2) respectively (in c)). In terms of fire 

damage area, the consequences could concern up to the half of the system (in b). Nevertheless, in terms of 

performance for the system, up to three functional zones may be affected, potentially bringing the daily 

performance of the system to a zero. Shifting to the "building-occupant" system paradigm will allow the FPEs 

to better understand how the system operates in a daily basis and therefore establish fire protection measures to 

mitigate the effects of fire events on this daily performance, which is what the stakeholders are concerned 

about. 

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FZ1 FZ2 

FZ3 SC1 

SC2 

FZ1 FZ2 

FZ3 

a) System division according to 

the "building-occupant" system 

paradigm - FZ: Functional zones 

b) System division according to 

the current PBFPD processes ­

SC: Smoke compartment 

c) Impact on the system Functional 

Zones based on the Smoke 

Compartment division 

Fig. 4-9. Concept differences between the FPE current paradigm and the "building-occupant" system paradigm 

As indicated above, targets are components of the system that contribute to the performance of the system. 

These targets can be affected by direct and indirect effects of a fire event. As an example, Fig. 4-10. illustrates 

the impact of the indirect effects of a fire on the overall system performance, focusing on how this indirect 

effect is not taken into consideration in the current PBFPD processes. Because shifting to the "buildingoccupant" system paradigm clearly shows the FPEs connections between utility zones and functional zones, the 

FPEs would be able to evaluate the indirect impact of a fire in an utility zone upon the overall performance of 

the system. 

UZ: 

Electrical 

Room 

Spatially 

remote 

Functional 

Zone 

Electrical 

Room 

Spatially 

remote 

Functional 

Zone 

a) System division according to 

the "building-occupant" system 

paradigm - UZ: Utility zone 

b) Smoke compartment 

solution adopted from current 

PBFPD processes. A fire in the 

electrical room will not damage 

the functional zone 

c) Impact on the system overall 

performance: Loss of Electricity in 

the Functional Zone: the Functional 

Zone is unable to perform 

UZ: 

Electrical 

Room 

Spatially 

remote 

Functional 

Zone 

Fig. 4-10. Indirect effects of a fire upon the overall "building-occupant" system performance 

The current PBFPD processes, being focused on the fire scenario, generally address fire "direct effects"; but are 

not describing how the "fire indirect effects" have to be analyzed and minimized. The new PBFPD process, 

being target-oriented, utilizes a fire risk analysis centered around the study of how often and how badly fire 

events can affect directly and indirectly the targets which contribute to the performance of the system. 

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Since the performance of a system is affected by potential damaging effects to the system targets, FPEs need to 

take these specifics into consideration when elaborating their fire strategy. The stakeholders are the ones who 

define the system targets when they elaborate the overall objective of their systems. Thus, it is essential that the 

stakeholders transfer the information related to the system targets as soon as possible to the FPEs, who can then 

design specific fire protection measures in order to minimizes the fire impact on these targets, so ultimately the 

performance of the system is the least affected by fire events. No current PBFPD process indicates to a FPE the 

need to examine such a level of details or explains the reasons why this level is important because such 

processes are still too focused on the fire scenario itself instead of being target-oriented. 

Fire protection measure reliability is not considered in the current PBFPD approaches based on a deterministic 

treatment of fire scenarios so that all the safety barriers are considered to be performing as designed. Exit 

signage is a typical example on how the efficiency of a fire protection feature varies from the design conceptual 

phase to the reality of the use in the system (Fig. 4-1). 

In the proposed PBFPD process, target oriented scenarios are established with event trees and fault trees in 

order to determine all of the possible paths that can led to a target being affected in the case of a fire disrupting 

the system. In the current PBFPD processes using a probabilistic approach, only event trees are considered as a 

technique to assess the likelihood of scenarios because these scenarios focus on the possible direct 

consequences of the fires themselves and how the fire protection measures would mitigate these consequences 

(e.g. appendix E titled "Risk Analysis" of the SFPE engineering 2.3 guide [5] or Section.2 of IFEG [6]). In 

some PBFPD processes, fault trees are also used but mainly to assess the conditions of fire ignition or the 

causes of failures of a fire protection measures. Still, they fail to assess indirect threat paths on targets. 

Technical fire protection measures are always indicated in examples of event trees. Human actions are indicated 

as additional sources of fire detection (e.g. nurse detecting a fire in a patient ward) or fire suppression (e.g. staff 

using portable fire extinguishers and of course fire fighters controlling and extinguishing a fire). Besides, I 

assume that some of the human actions are also considered in fault trees related to fire ignition frequency 

(arson, poor maintenance of electric equipment, uncontrolled hot spot...). Nevertheless, I have not seen in event 

trees the impact of actions of humans leading to an aggravation of the consequences of fire scenarios. Maybe 

some of them are embedded in the fire parameters themselves, like an unauthorized use of fireworks, which is 

an important fire ignition source and which can potentially lead to a rapid fire spread. But what about "over 

capacitating of the system" as it was repeatedly observed in the aforementioned night club disasters? Indeed, 

this "human action" item is "controlled" by the regulation and needs enforcement but within the "buildingoccupant" system framework, it is clear that item has to be considered in the PBFPD process as it is a flagrant 

example on how a "chronic" objective of a night club owner related to profitability competes with fire safety 

objective. Less flagrant but worth noticing are similar incidences in department stores during sales or airports 

during holiday seasons or right after strikes. 

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Contrary to fire scenarios developed in the current PBFPD processes, the proposed process extend scenarios to 

take into consideration the period from fire extinguishment to the establishment of a new "chronic" state of the 

system, as explained in Chapter 3 of this dissertation. 

4.5.4 Fire risk analysis (quantification of the impact) 

4.5.4.1 Quantification of impact vs. quantification of consequences 

As already indicated, fire scenario consequences are not limited to the extent of safe evacuation or direct fire 

damage, but they should include the effects of fighting the fire, including in term of monetary loss. Assessment 

of all impacts should be considered. For example, in open spaces, even if sprinkler heads locally activate, water 

tends to spread over a larger area than the area directly affected by the fire. As an example, at the Myrtle Beach 

Convention Center (USA), on October 12, 2011, a fire that started on a cherry picker lift in an exhibit hall 

activated sprinkler heads, which controlled the extent of fire spread. However, given the volume of smoke 

produced, a 2-hour effort by firefighters to remove the heavy smoke out of the exhibit hall was needed. 

Extensive damage to the machinery and water damage in the convention center were reported [7]. This example 

illustrates the concern that originates from the difference of perspective between the FPE who follows generic 

guidance to determine direct damages of the fire (e.g. sprinkler automatic system is adequate as the directly 

damaged area was small) and the building owner who is mainly interested in renting his convention center (e.g. 

water from sprinklers and smoke from the fire rendered useless a larger part of the convention center, which 

required cleaning before the overall damaged space was usable again). A more comprehensive and detailed 

example is presented in Chapter 3 of this dissertation, which clearly shows the dramatic aftermath of a cell 

phone company after a 10 minute fire. 

The current PBFPD processes only deal with the direct consequences of a fire whereas the proposed process 

advocates for the quantification of fire impact of targets which contribute to the overall performance of a 

"building-occupant" system, evaluating direct and indirect fire effects as indicated in Section 4.5.2 and Section 

4.5.3 of this chapter. Once again, the current PBFPD processes which are focused on fire scenarios, estimate 

direct fire effects between ignition and extinguishment, so they do not take into consideration the response of 

the different targets as well as the "recovery period" of the fire event. 

As the proposed process is "target oriented", the FPE looks for this information which is essential for the study 

of the effects of fire events on the overall performance of a "building-occupant" system. 

4.5.4.2 Tools and data needed for the quantification of the impact of fire events 

Consequences on building occupants are often estimated via the (RSET / ASET) concept where RSET is the 

Required Safe Egress Time (i.e. time for building occupants to safely evacuate) and ASET is the Available Safe 

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Egress Time (i.e. time before untenable conditions appear). This concept is currently applied in too much of an 

independent manner: on the one hand, using fire effects models, the FPE estimates the time to reach untenable 

conditions. On the other hand, as a completely independent calculation, using egress models, the FPE estimates 

the time required for the building occupants to reach a place of safety. Emphasis is given on the "fire" 

estimation as FPEs are trained to do such estimations but uncertainties related to human behavior in fires are 

still nowadays quite significant to drive the validity of all the (RSET / ASET) estimation. 

Not enough guidance on how human behavior affects the results of the evaluation of fire scenario consequences 

is contained in the current PBFPD guidelines and the current process framework advocates for more guidance, 

as well as a more dynamic integration of the two calculations (fire and evacuation) [8]. 

For this step, the proposed PBFPD process focuses FPEs on the "building-occupant" system, which requires 

integrated analysis to be conducted of the building-occupant-fire situation. In addition, the proposed process 

defines a framework for collaborative projects, called 'test bed' environments [9], developed to facilitate the 

determination of the most appropriate tools, data and methods for FPEs to apply in order to quantify fire 

impacts for specific "building-occupant" systems and for specific issues such as occupant evacuation, property 

protection or building structural response. In the future, guidance established during these projects in 

cooperation with stakeholders (including AHJs) would speed up the validation of the use of tools for their 

corresponding systems and issues, while decreasing the uncertainties due to the tool models, input data and tool 

user. 

4.5.5 Integration of the fire protection measures into the "building-occupant" system 

Since the current PBFPD processes consider the installation and the maintenance of fire protection measures 

after the stakeholders agree on them, the responsibility shifts from the designer (FPE) to the user (building 

owner and occupants) to maintain with time the operability and the efficiency of the fire protection measures. 

The current process analyses the effects of integrating fire protection measures into the system in order to 

prevent these measures from being counterproductive or even "rejected" by the system. During the Pattaya 

Royal Resort hotel fire, June 11, 1997, emergency doors were locked by hotel operators to prevent customers 

from leaving without paying. This Code violation in conjunction with a lack of sprinkler system and no fire 

alarm heard by the survivors were the main causes of at least 78 casualties and at least 64 injured people. Also 

in Thailand, in 1993, a fire in a toy factory killed 188 people and police reported that factory supervisors had 

locked the exits to prevent workers from taking breaks [10]. Exits doors "locked in an effort to monitor 

employees and prevent theft" was also observed, among many other deficiencies in the Triangle Shirtwaist Fire 

that happened in a factory in New York, on March 25, 1911, (one century ago) killing 147 of the more than 500 

employees [11]. 

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Lack of code enforcement is also to blame partially in the fire that occurred in a chicken processing plant in 

Hamlet (North Carolina, USA) September 3, 1991, leading to 25 fatalities and 54 injured people. The plant had 

not been inspected during the 11-year operation of the plant, several doors leading to the outside were locked, 

and survivors indicated that there was no real organization in the plant's evacuation [12]. 

As an example of how some fire protection measures can be "rejected" by the system, Fig. 4-11. illustrates that 

competition between "chronic" objectives and fire safety ones does not go in favor of the latter one. The picture 

in Fig. 4-11. has been taken in an actual hotel, where a vestibule with two fire rating doors has been design to 

protect the single stairwell of the hotel from being invaded by smoke in case of a fire spreading in the corridor 

where the hotel rooms were located. The "chronic" objective is related to the ease of passage between the hotel 

rooms to the lobby via the stairwell. The objective clearly supersedes the objective to maintain an eventual 

smoke separation with the vestibule. 

As mentioned in Section 4.2 of this chapter, current PBFPD processes consider fire protection measures as 

independent of the system in which they are installed. While these measures are required to be maintained 

according to design specifications, the current processes do not include a mechanism to verify how these 

measures would be perceived by the building occupant before and more dramatically when a fire occurs. In that 

perspective, FPEs design "independent" fire protection measures and they estimate that the system, in which 

these measures are installed and maintained according to their design, will conform to all these specifications 

(i.e. that the system will adapt by itself to these specifications). 

This specific step of the proposed PBFPD process is aimed to avoid critical situations where the fire protection 

measures installed in a "building-occupant" system are ignored, or "rejected" by this system, potentially leading 

to a catastrophe in case of a fire occurring. The "chronic" use of the system needs to be addressed and as for the 

previous process steps, it relies on the stakeholders' input during the initial step of the process in terms of 

"competing objectives". For the example illustrated by Fig. 4-11, a FPE might suggest the use of a smoke 

vestibule as a smoke control feature, yet not thinking about how that system could be defeated by the daily use 

of the hotel patrons whose objective is to have an unobstructed path while carrying their luggage from their 

room to the lobby via the stairwell. In my approach, in the document related to this process step, the FPE would 

have to communicate to the hotel stakeholders how fire safety management would address this, and if not 

deemed reliable by the stakeholders according to their "chronic" objectives, propose another option. 

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Fig. 4-11. Blocked opened doors in a vestibule separating hotel room corridor from a stairwell in a hotel 

4.5.6 Cost-Benefit analysis of the fire protection measures 

Building owners usually want to spend an optimum of resources correlating the cost associated with fire 

protection measures and their benefits, according to the level of fire risk they are ready to accept (level 

evaluation that I consider as a political decision in this research). 

In the current PBFPD processes, SFPE [5] indicates that "if several successful trial designs are available, cost 

could be one of the factors used to select which successful alternative is used". Effectiveness of the fire 

protection measures defined by their availability (capability of the measure to perform its fire safety function at 

a given time) and their reliability, is also one of these factors. Nevertheless, SFPE does not indicate how these 

different factors should be evaluated and presented to the different stakeholders for their judgment (i.e. how a 

more effective but more costly measure should be finally installed instead of a less effective but less expensive 

one). 

The "Cost-Benefit analysis" Step is the last technical step of the proposed PBFPD process. This would not be 

suggested but required. Guidance would need to be developed, based on approaches outlined by Ramachandran 

[13], Watts and Chapman [14] or others. The Cost-Benefit analysis, in conjunction with Step 3, which assesses 

the reliability of fire protection measures, and Step 5, which evaluates how these measures are designed and 

maintained in order to be well integrated in the system, represents the package of information that the FPE 

needs to provide so that in the final step of the process, stakeholders are able to make an informed decision of 

the fire protection measures based on system options, reliability and cost factors and finally select the ones for 

their system. 

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4.6 Conclusions for this chapter 

Research was undertaken as a response to the shortcomings and challenges related to the application of current 

performance-based fire protection design (PBFPD) processes. These difficulties were interpreted as a 

consequence of having generic guidelines for these processes which strongly rely on a political agreement 

between project stakeholders and the fire protection engineers. Besides, these generic guidelines seem too 

focused on fire scenarios so that fire protection measures deemed appropriate at the time of design might not be 

the most appropriate when implemented in a building, as key aspects of the fire protection design might be 

ignored or worse "rejected" by the occupants of the building when needed the most, since fire is not a daily 

concern. 

As a consequence, it was estimated that a paradigm shift from one in which fire is the center of the problem to 

one in which building performance metrics are evaluated in the case of fire events, was necessary before 

implementing a new PBFPD process able to overcome all the current difficulties. A "building-occupant" system 

paradigm was then established along with a new risk-informed performance-based process focused on assessing 

the overall performance of the system in case of any type of event affecting its performance. 

This chapter presented how this system performance-based process can be used for the treatment of fire events 

and how this new PBFPD process differs from the current ones. The new PBFPD process is system specific, so 

its associated guidelines cannot be generic as they are established by system categories. 

Being focused on the system, a fire risk analysis is performed centered on the study of the actors of the system 

everyday performance and how fire protection measures can mitigate the effects of fire events on this everyday 

performance. Besides, the new PBFPD process contains a technical step dedicated on the evaluation of the 

integration into the system of the fire protection measures, selected after the fire risk analysis. A cost-benefit 

analysis finalizes the technical part of the process which has been performed independently and in a 

straightforward manner by fire protection engineers (FPEs). At the end of this technical part, FPEs have 

elaborated three documents detailing the results of the fire risk analysis, of the evaluation of the integration of 

the fire protection measures into the system and of the cost-benefit analysis. Based upon these documents, the 

stakeholders decide which fire protection measures they would have installed in their system. This process is 

then showing a complete separation between the "political" decision-making process and the "technical" 

resolution of the engineering fire problem, 

As a proof of concept, it has been shown through text and examples how the new framework addressed the 

challenges with the existing approaches, operated within a more holistic "building-occupant" system paradigm, 

illustrated how viewing fire as a perturbation within the larger "building-occupant" system would increase fire 

safety performance over the life of a building, and deliver a higher level of building fire safety performance. 

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For the time being, no detailed guidance has been established for the new PBFPD process. Nevertheless, the 

following chapter of this dissertation will describe how the new PBFPD process is implemented. In other terms, 

Chapter 5 contains a possible plan of action needed to set up the basis for models and databases that would 

ultimately be part of system specific guidelines related to each of the technical steps of the process. Due to the 

facts that the technical steps of the process are connected in terms of input-output and that they will require the 

competencies of FPEs, stakeholders, policy makers, experts in fire science, human behavior, structural 

engineering, toxicology and economics, it is already anticipated that this plan of action to be iterative. 

References 

1.	 A. Alvarez, B.J. Meacham, Towards an Integrated Performance-Based Design Approach for Life Safety Across 

Different Building Use Groups, in: Proceedings of the 12th International Interflam Conference, Nottingham, UK, 2010 

2.	 E. Comeau, M. Puchovsky, NFPA Fire investigation report, Warehouse fire, New Orleans, Louisiana, March 21, 1996, 

National Fire Protection Association, 1996 

3.	 J. Stern-Gottfried, G. Rein, Travelling Fires for Structural Design-Part I: Literature Review, Fire Saf. J. 54 (2012) 74­

85 

4.	 V.A. Oven and N. Cakici, Modelling the evacuation of a high-rise office building in Istanbul, Fire Saf. J. 44 (2009) 1­

15 

5.	 SFPE, SFPE Engineering Guide to Performance-Based Fire Protection, 2nd edition, Society of Fire Protection 

Engineers, 2007 

6.	 IFEG International Fire Engineering Guidelines, Australian Building Codes Board, Department of Building and 

Housing (New Zealand), International Code Council (USA), and National Research Council (Canada), 2005 edition 

7.	 Firefighting News, Firefighters battle blaze at Myrtle Beach Convention Center, (available at: 

http://www.firefightingnews.com/article-us.cfm?articleID=102260, last checked 2012-09-20) 2011 

8.	 V. Babrauskas, J.M. Fleming and B.D. Russel, RSET/ASET, a flawed concept for fire safety assessment, Fire and 

Materials 2010; 34:341-355 

9.	 A. Alvarez and B.J. Meacham, 'Test bed' environment process for assessing the appropriateness of engineering tools to 

be used in performance-based design applications, Proceedings of the 9th International Conference on PerformanceBased Codes and Fire Safety Design Methods, 20-22 June 2012, Hong Kong, 2012 

10.	 The Independent, Hotel blamed as fire kills 78 at Thai beach resort, (available at: 

http://www.independent.co.uk/news/world/hotel-blamed-as-fire-kills-78-at-thai-beach-resort-1250217.html, checked 

2012-09-20), 1997 

11.	 J.S. Tubbs and B.J. Meacham, "Historic Events", chapter 2 of Egress Design Solutions – A Guide to Evacuation and 

Crowd Management Planning, John Wiley and sons, 2007 

12.	 J. Yatts, Chicken Processing Plant Fires – Hamlet, North Carolina, and North Little Rock, Arkansas, Technical Report 

Series, United States Fire Administration, 1991 

13.	 G. Ramachandran, Economics of Fire Protection, Routledge, New York, 1998 

14.	 J.M. Watts Jr. and R.E. Chapman, in: P.J. DiNenno (Ed.), Engineering Economics, The SFPE Handbook of Fire 

Protection Engineering, fourth ed., National Fire Protection Association, Quincy, MA 02269, 2008 pp. 5/129–145. 

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5.	 ESTABLISHING A PLAN OF ACTION FOR THE DEVELOPMENT OF 

GUIDELINES IN SUPPORT OF THE FRAMEWORK FOR RISK-INFORMED 

PERFORMANCE-BASED FIRE PROTECTION DESIGN 

In order to apply the new PBFPD process to a specific system, FPEs would base their work upon guidelines 

written for each of the technical steps of the process and established for specific types of systems, since it has 

been demonstrated, in the previous chapters of this dissertation, that generic guidelines are at the origin of 

challenges when applying them to specific projects. 

These guidelines for the specific systems are not as yet written as the required research still has to be carried 

out. Nevertheless, a plan of action (Fig. 5-1) applicable to any disruptive event type, including fire, is proposed 

in order to: 

- collect and compile information from research associated with each step of the process. This information 

primarily comes from technical literature where general advances in all of the corresponding fields (fire 

research, human behavior, material engineering...) are applied to specific systems. At this stage, input from 

stakeholders is essential as they have the best knowledge of the characteristics of their systems (in terms of 

target definitions and attributes, descriptions of functional zones and utility zones and how the system 

performs in a daily basis). Some important results found for a particular step can be used as input for 

research associated with a subsequent step of the PBFPD process. 

- establish guidelines or standards associated with each step of the process. The aim of the performed 

research gathering together stakeholders, fire protection engineering and experts in different fields, is to 

produce specific guidelines for each step and specific "building-occupant" systems. It is intended that if 

generic standards, guides and guidelines are already published or in progress in relation to a process step, 

they would be integrated within the "building-occupant" paradigm. It is also conceived that specific system 

guidelines may have a common aspects or comparison between different systems may be looked at. For 

example, in order to avoid the multiplicity of databases, a global database regrouping common attributes 

defined across multiple "building-occupant" systems may be created and consolidated with specific data. 

Methods, models and tools developed in a generalized and consistent manner to quantify fire events will 

also be considered in the guidelines and standards, as the most appropriate of them would be used to 

describe fire events occurring in such and such systems and would be detailed in the corresponding 

guidelines. 

- thus, by "climbing the research to application/regulatory ladder", the FPE at the top the "ladder" will use 

guidelines and standards established for specific "building-occupant" systems, along with databases 

containing information and data relevant to the matter being considered. 

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Input from experts in their fields 

Input from technical literature 

Input for research associated with another system 

performance-based process step 

Climbing the Research to

Application / Regulatory ladder

Standards, guides and guidelines 

already published or in progress 

Guideline or standard 

associated with the system 

performance-based process 

step 

Research associated with the 

system performance-based 

process step 

Input from stakeholders 

Attributes for the development 

and use of databases, lists, 

tools... 

system performance-based 

process Step +1 

system performance-based 

process Step -1 

system performance-based 

process Step 

Fig. 5-1. Plan of action: "climbing the research to application/regulatory ladder" 

This chapter proposes, for each technical step of the process, a plan of action including information that can 

already be extracted from past and current research. As well it outlines how I anticipate the future guidelines 

and standards related to the application of the new PBFPD process will be composed and structured. This plan 

of action, illustrated with Fig. 5-1, is planned to serve as the template of a decision-making process for the 

creation of the corresponding guidelines and standards for each step of the system performance-based process. 

5.1 The need for an iterative plan of action 

To perform, the PBFPD process presented in the previous section for a particular "building-occupant" system, 

FPEs need all the information related to the problem definition, that is to say the characteristics of the "buildingoccupant" system, including the nature of the different targets which determine the overall performance of the 

system. In order to perform the six different steps of the risk-informed PBFPD process, important information 

from the stakeholder has also to be collected, for each step of the process, as shown in Fig. 5-2. 

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Input from stakeholders, by 

building occupancy types 

and "building-occupant" 

systems to help define risk 

metrics 

Input from building 

owners, users and 

designers, to determine a 

list of targets by 

"building-occupant" 

systems 

Input from designers to 

get the list of targets to 

protect, the definition of 

the "functional zones", 

etc., as well as the 

possible relationships 

between building 

occupants and building 

components 

Input from regulators, 

fire protection 

engineers and building 

designers to establish 

case studies, use same 

building configurations 

and share tool use 

knowledge 

Input from existing 

contingency plans for 

"building-occupant" 

systems 

Stakeholders’ 

decisions 

Stakeholders’ 

project 

definition 

Technical steps of the new PBFPD process 

Risk 

characterization 

Target 

vulnerability 

criteria 

estimation 

Fire Risk 

analysis 

(quantification of 

the likelihood) 

Fire Risk 

analysis 

(quantification of 

the impacts) 

Evaluation of the 

integration of the 

fire protection 

measures in the 

system 

Cost-benefit 

analysis 

Guideline for 

evaluating the cost 

of integration of 

the fire protection 

measures in the 

system 

Research for 

evaluating the cost 

of integration of 

the fire protection 

measures in the 

system 

Guideline or 

standard for 

assessing risk 

characterization 

for "buildingoccupant" systems 

Research for risk 

characterization 

for "buildingoccupant" systems 

Guideline or 

Standard for 

vulnerability 

criteria of 

human/equipment/ 

structures in case 

of fire event 

Research for 

vulnerability 

criteria of 

human/equipment/ 

structures in case 

of fire event 

Guideline or 

standard level for 

defining fire event 

for "buildingoccupant" systems 

Research for 

defining fire 

scenarios for 

"buildingoccupant" systems 

Guideline for 

assessing the 

appropriateness of 

tools to be used for 

a given FPE 

application 

'Test bed' 

environment to 

assess the 

appropriateness of 

tools to be used for 

a given application 

Guideline for 

evaluating the 

integration of the 

fire protection 

measures in the 

system 

Research for 

evaluating the 

integration of the 

fire protection 

measures in the 

system 

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Fig. 5-2. Influence of stakeholders’ input on the PBFPD process 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Input from the stakeholders is necessary to apply the research to "building-occupant" systems of interest, to canalize 

this research to obtain the corresponding guidelines in the shortest times possible. For example, the application of 

decision-making processes similar to that presented in Fig. 5-1 demonstrate that it has been successful in 

overcoming technical and political obstacles in risk-informed performance-based design processes concerning 

hazardous facilities. These applications namely concern industrial plants in France [1] and nuclear power plants in 

the USA [2,3]. Bringing all the aforementioned participants together allowed in the French example the shift of the 

regulation from a prescriptive method related to the prevention of the worst case scenarios and land management to 

a probabilistic risk assessment of all the possible scenarios (fires, explosions and toxic releases) having 

consequences outside of a considered industrial plant. Dedicated groups were organized according to the type of 

activity and hazardous products (e.g. chlorine fabrication, LPG (Liquefied Petroleum Gas) storage facilities, oil 

refineries). The US example was dedicated to the effects of potential fires on the safety of the pieces of equipment 

which maintain the nuclear core in a safe state. 

The French example concerned the safety of the population located outside the plant and the environmental impact 

of the industrial plant. The evaluation of the consequences of a fire in a populated building requires the evaluation of 

both the fire effects (temperature increase, production and spread of smoke and toxic effluents) and the evacuation 

process (when people need to evacuate the building to a safe place). This latter, complex but essential evaluation has 

not been considered in the two aforementioned studies so it is not possible to directly transfer their results to the 

built environment. It should be noted that communication between research groups dedicated to each step of the 

process would be necessary because of the interconnections between the research on a specific step as illustrated in 

Fig. 5-3. Thus, the process needs to be iterative since output from some research on specific steps is necessary input 

for research on other steps in the process. 

Besides, the needed research is both generic and applied: 

- it is generic regarding research concerning the tools used in any step which is currently producing more 

elaborated tools that can be used in the PBFPD process. Advances in fire protection engineering tools is, of 

course, my main concern when looking at tools which are used to quantify the effects of a fire, but I will also be 

looking at tools which can help and speed up the process when dealing with statistics, risk analysis, and cost 

benefit analysis. 

- it is applied regarding research concerning the data which would serve as input data for the models and tools. 

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Research for 

evaluating the cost 

of integration of 

the fire protection 

measures in the 

system 

Research for risk 

characterization 

for "buildingoccupant" systems 

Research for 

vulnerability 

criteria of 

human/equipment/ 

structures in case 

of fire event 

Research for 

defining fire 

scenarios for 

building-occupant 

systems 

'Test bed' 

environment to 

assess the 

appropriateness of 

tools to be used for 

a given application 

Research for 

evaluating the 

integration of the 

fire protection 

measures in the 

system 

Output for documentation – most important safety barriers 

Output for fire risk analysis 

Output for fire effects tool / evacuation tool / structural tool developers 

and users 

Fig. 5-3. Interconnections between the step researches of the proposed PBFPD process 

Regarding the validation of tools, since each of the "building-occupant" system of interest constitutes a microdomain of analysis and study, it will not be necessary to have the tools validated on a macro-scale (i.e. all their 

possible domains of application) but around each established micro-domain, and this is the case for all of the tools 

used in the different steps of the process. The same concept can be applied for data research: small groups of experts 

dedicated to the study of particular "building-occupant" systems can work a lot more efficiently than researchers 

looking to embrace all the possible data distribution for the whole building environment. 

In consequence, because the generic problem is broken into manageable and well defined pieces, i.e. the "buildingoccupant" systems, the iterations needed to conduct the research and establish the guidelines would be much quicker 

than trying to solve the engineering problem in a generic way. Besides, since every system has its own 

characteristics, not only the aforementioned technical challenges would be solved more quickly, but also the risk 

characterization components of this process would be better accepted as risk mechanisms (risk control, risk aversion, 

etc.) are not perceived the same way by stakeholders dealing, for example, with hospitals, schools or high-rise office 

buildings. 

At last, in the USA, the National Fire Protection Association organizes committees in order to establish standards 

related to requirements and recommendations related to fire protection of specific building types. For example, the 

technical correlating committee on health care facilities was created to write the NFPA 99 Standard for Health Care 

Facilities [4] and it gathered members from health care systems, academics, US departments, fire protection 

consulting companies and fire protection equipment manufacturers. Organizing similar groups or taking advantages 

of these committees would also benefit the development of the different guidelines of the risk-informed PBFPD 

process. 

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5.2	 Importance of the involvement of the stakeholders for establishing validation domain of 

models needed at each step of the PBFPD process 

In the past decades, models has been developed in a generic form because there was a tremendous need for 

fundamental research to describe and quantify all the different phenomena involved in a fire engineering evaluation, 

from the effects of the fire itself, to the building occupant process and the response of the building structure. 

Validation of these "research" models, as opposed to "engineering" models inscribed in codes and standards, has 

been and still remains a central question in the acceptance, by the authorities having jurisdiction, of engineering 

reports using the performance-based option of building codes [5]. Due to the complexity of the different types of 

aforementioned phenomena, scientists developed semi-empirical models based on a theoretical approach of the 

phenomenon completed by a "tuning" of these theoretical models with empiric correlations or factors. Thus, the 

contours of the validation domains of these semi-empirical models mainly correspond to the boundaries of the 

experimental tests that served to "tune" the models. It should be noted that setting up experiments for determining 

validation domains and thereafter increase them is a costly enterprise in terms of time and resources. Besides, as 

some empirical parameters are model dependant, experiments especially set up for assessing parameter values for 

one particular model may not be valuable or simply usable for increasing the validation domains of other models 

dealing with the same phenomenon as the other models may also have their own model dependant parameters which 

would have required different or additional specific experimental setting up. 

Involvement of the project stakeholders is also crucial, not only for the execution of the political steps of the PBFPD 

process when this process will be applied to a particular project but also during all the process required to establish 

the corresponding step guidelines of the PBFPD process. This involvement is indeed essential because the 

stakeholders are the ones who know best the system they have designed and that they will ultimately use on a daily 

basis. The stakeholders know how the system behaves in a daily basis so they are able to describe, in details, the 

corresponding characteristic of the building components as well as the characteristics of the building occupants of 

the their system. 

Benefits of having stakeholders participating at the research stage of each path include a better use of research as 

their data identifier input (i.e. targets' characteristics, risk metrics, functional zones, contingency plans...) would 

drive the need to obtain research data pertinent and if possible directly applicable all along the proposed PBFPD 

process. As a result of this participation at the research stage, the guidelines would contain if not all data values, 

processes that could lead to collect data while minimizing uncertainties and the use of engineering judgment. 

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5.3	 Application of the plan of action to obtain the necessary guidelines to perform each step 

of the new PBFPD process 

As illustrated in Fig. 5-2, six different technical steps are required to be performed by the fire protection engineer. 

This section briefly presents a possible way to elaborate these guidelines from research, past, present and future. 

Each guideline elaboration process is derived from the one presented for a risk-informed approach (Fig. 5-1), as 

each step requires the participation not only of FPEs and scientists, but also public officials and interested 

stakeholders. 

5.3.1 Proposed path of action to quantify Step 1: risk characterization 

5.3.1.1 Description of the risk characterization step and corresponding path of action 

Risk characterization is the most important step of the process, as it defines and frames the engineering problem to 

be solved by the FPEs. 

Within my "building-occupant" system paradigm described in detail in Chapter 3 of this dissertation, the system 

stakeholders define the main characteristics of their existing system or project, in the political initial step of the 

PBFPD process. They are concerned about the overall performance of their system, which is dependant of the 

"chronic objectives" associated with the system and they would like to know how this performance is affected in the 

case of fire events. The performance of the system is a function of the activity of the system "targets". 

Since targets are defined as the actors of this performance, it is essential that the FPEs collect the list of these targets 

from the system stakeholders. The stakeholders' view of the fire problem is on the long term; in other terms fire 

events are disruptive events among many susceptible to occur during the lifespan of the system. The FPEs' view of 

the fire problem is focused on the fire disruptive events, how often they can occur and with which effects they have 

on the system targets. 

The risk characterization step can be seen as the transfer of this problem, from the stakeholders' perspective to the 

fire protection engineer's perspective. Based on the stakeholders' list of system targets, FPEs have to define risk 

metrics which associate the frequency of the fire events with their effects on the system targets, as well as a 

quantification of these risk metrics. 

I estimate that guidance related to current PBPFD processes focuses too early on the fire events for which safety 

goals and objectives are established upfront, leading to a potential disconnection between the stakeholders' overall 

concerns and the FPE specific fire-oriented analysis. The Risk characterization step is not only aimed at avoiding 

this disconnection at the start of the new PBFPD process (i.e. solving the wrong problem), but it is also useful at the 

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end of the process when the FPEs communicate their results to the stakeholders as they can easily "transfer back" 

these results into the stakeholders' perspective. 

The corresponding path to quantify the risk characterization step of the PBFPD process is illustrated in Fig. 5-4, and 

detailed in the following paragraphs. 

Guideline or standard for 

assessing risk 

characterization for buildingoccupant systems 

Research for risk 

characterization for buildingoccupant systems 

Risk characterization 

Input from stakeholders, by building 

occupancy types and building-occupant Output for fire risk analysis systems to help define risk metrics 

Fig. 5-4. Proposed path to risk acceptance characterization 

5.3.1.2 Research to be carried out for "Risk characterization" Step 

At a research level, stakeholders involved in similar "building-occupant" systems would help the fire protection 

engineer define the metrics that corresponds the closest to their own view on the performance of the systems. 

Since these metrics are tied to the systems they represent, a possible formulation for these metrics is a fraction where 

the numerator deals with the fire events in a defined period of time and the denominator describes a relevant 

parameter of the system. Different objectives may be considered by the different stakeholders. All stakeholders are 

concerned by life safety so the metric numerator should include parameters dealing, for example, with annual deaths 

and injuries caused by fires affecting the considered systems; the denominator would include some information 

relevant to the activity of the occupant in the considered building. For property protection, the numerator of the 

corresponding metric could include parameters describing, for example, the amount of damage due to fires, 

including direct and indirect fire damage. For business interruption, the metric numerator could include the number 

of days lost in production due to fire events in similar industrial systems. Climbing the Research to Application / Regulatory ladder

Standards, guides and guidelines 

already published or in progress 

Input from Bureau of Census type of 

organizations to get an estimation of 

building-occupant systems 

Input from fire statistics and analysis of 

past events 

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Within the presented process, I consider that risk characterization may be assessed on two different set of data: 

- fire statistics, which provide fire frequencies and damage estimation, 

- census data related to defined "building-occupant" systems, which provides information of the number of 

systems within the same category. 

In the USA, the National Fire Protection Association [6] and the Fire Administration [7] periodically publish fire 

statistics. Special reports are also published by building occupancy types [8]. Alvarez and Meacham [9] give 

examples of US census database consultation, for different system categories. 

Within the "building-occupant" system paradigm, stakeholders identify targets and risk identification is carried out 

to figure out how fires can affect the targets and lead to a change of the system performance. It should be noted that 

several authors already applied this way of looking at fire statistics and tried to determine which metrics were the 

most appropriate to represent fire risk and communicate concerning the policy levels of this risk for different 

systems. 

Examples from the technical literature showed that data, even if not "complete and perfect" [8,10-13], can be 

associated and treated by system category. Thus, Kobayashi and Nozaki [14] looked at different Japanese sources, 

which classified non residential buildings in several categories. Table 5-1 presents their findings related to 

commercial buildings, as they defined four different classes based on floor area and number of stories. Fig. 5-5 

presents the corresponding fire risk with an estimation of the damage area as a function of annual exceedance of 

probability. 

Table 5-1. Calculations conditions for example risk curves [14] 

Classification Median floor area (m2) Median Number of Stories 

Group "H" 36,597 10 

Group "LL" 31,124 5 

Group "LM" 11,239 4 

Group "LS" 2,148 2 

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Damaged Area (square meters)

1.0E+04 

Group "H" 

Group "LL" 

1.0E+03 Group "LM" 

Group "LS" 

1.0E+02 

1.0E+01 

1.0E+00 

1.0E-00 1.0E-01 1.0E-02 1.0E-03 1.0E-04 1.0E-05 1.0E-06 

Annual Exceedance of Probability (1/year) 

Fig. 5-5. Example of fire risk curves for commercial buildings [14] 

Risk matrix or fire risk curves such as the one presented in Fig. 5-5. can be established for "building-occupant" 

systems, based on the corresponding fire statistics which describe the appropriate metric for each objective 

considered by the project stakeholders. For example, Tsujimoto [15] presented fire risks to Japanese occupants in 

residential buildings, hospitals and hotels from 1969 to 2000, as annual deaths per 105 users’ year stays in each kind 

of place with the corresponding metrics: 

þþ þ ÿ þ  - for residential buildings: 

	 þ 

- for hospitals: þ 
 

þþ þ ÿ 
þ  

ÿ  ÿ  þ
þ!  þþ  þ! 

- for hotels: þþ þ ÿ  

þþ þ 
 ÿ   

Based on these metrics, he presented the death risk a person takes at one night in each place (Fig. 5-6). 

0 

0.5 

1 

1.5 

2 

2.5 

3 

3.5 

4 

Annual Death / 105 Users/Year 

Residence Hospital Hotel 

1970 1975 1980 1985 1990 1995 2000 

Year 

Fig. 5-6. Death risk trends in Japanese residential buildings, hospitals and hotels between 1969 and 2000 [15] 

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Particular care should be taken when aggregating buildings into a similar category. This situation is not only due to 

the evolution with time of building characteristics (e.g. open space office floors versus compartmented office floors) 

but also due to the evolution with time of building code prescriptive requirements regarding fire safety. For example, 

Tsujimoto [15] also looked at establishing a correlation between fatalities in hospitals and the number of beds with 

or without sprinklers (Fig. 5-7), mainly between 1960 and 2000. He listed the regulatory changes concerning the 

installation of sprinkler systems in Japanese hospitals during the same period (Table 5-2) and established a relation 

between fire death and the number of beds with and without sprinkler estimated by the change of fire code 

summarized in Table 5-2 and statistics about hospitals. 

Table 5-2. Transition of Requirement for Sprinkler Installation of Hospital (Fire Code in Japan) [15] 

1961.4 patients room over 4th floor ≧ 1500 m2 

1967.7 4th floor to 10th floor 

floor area more than 100 m2 over 11th floor 

1973.6 

total floor area is over 6000 m2 except one-story hospital 

over 11th floor 

floor area more than 1000 m2 which floor is underground or without window 

1974.6 retroactive application to existing building 

1988.4 total floor area is over 3000 m2 except one-story hospital 

180 36 

Total number of beds 

Number of beds without sprinkler 

Fatalities of hospital fires (person / year) 

160 32 

Fatalities of hospital fires (person / year) 

140 28 

Total number of beds (x10,000) 120 24 

100 20 

80 16 

60 12 

40 8 

20 4 

0 0 

1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 

Year 

Fig. 5-7. Correlation between Fatalities in Hospital and Number of Beds [15] 

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It should be noted that some information output collected while performing research for the risk characterization 

Step (e.g. information related to the characterization of fires and of the considered systems) can be used as input for 

the next steps related to fire risk analysis (fire likelihood and fire consequence evaluation). For example, while 

assessing information about fire statistics and past fire events, elements of information related to scenarios, fire 

ignition, fire propagation in terms of frequency and intensity of damage should also be collected. Also, within the 

"building-occupant" system paradigm, characteristics of the different types of systems should also be collected so to 

have more information about the potential targets located inside the different parts of the systems. 

The aforementioned examples collected in the technical literature appear to be almost applicable within the risk 

characterization step of the new PBFPD process. The methods followed by the different authors would also serve as 

a basis for the risk characterization guidelines and standards. 

5.3.1.3 Establishing guidelines or standards for assessing risk characterization for "building-occupant" systems 

Standards, guides and guidelines dedicated to fire risk assessment or containing elements dealing with risk
 

assessment are already published or in progress [16,17]. Guidance provided by these documents is still generic but 

contains some useful elements to be adapted in the new "building-occupant" system paradigm.
 

A major concern regarding the use of data for assessing risk characterization for "building-occupant" systems comes
 

from the different origins of the needed data. For example, in the USA, the classification of buildings is not the same 

when established by:
 

- the National Fire Protection Association, which deals with fire statistics and proposes fire protection standards,
 

- the International Code Council, which elaborates building codes,
 

- the architects, who design buildings according specific functions,
 

- the Bureau of Census, which codifies business buildings according their activities.
 

Due to the fact that each of the corresponding building classifications were elaborated according to specific 

objectives, it would be quite difficult to look for a homogenous taxonomy across so many fields. Nevertheless,
 

within the "building-occupant" system paradigm, guidance is provided by system category. In consequence, it is
 

imperative that the system be well defined for each PBFPD step guidance and especially for the first step, which is
 

the one defining the engineering problem to be solved.
 

Guidelines or standards for assessing risk characterization for "building-occupant" systems shall clearly state the
 

definition of the system concerned by these guidelines or standards.
 

Once the system is well defined, the guidelines or standards related to the new PBFPD process Step 1 would contain
 

information related to well defined "building-occupant" systems, including the definition of the system targets and
 

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their associated risk metrics for relevant objectives (life safety, property protection, business continuity...) as well as 

the quantification of these risk metrics, or at least a way to obtain this quantification, as again countries, regions and 

even cities may have been developing their own databases regarding fire safety and building/person census. 

5.3.1.4 Using the guidelines for performing Step 1 in a PBFPD process 

Once the guidelines related to Step 1 have been published for well defined "building-occupant" systems, the FPE 

can use its guidance for a project covered by the corresponding guideline as a means: 

- To determine the targets which define the performance of the system according to the stakeholders, and 

- To document how the fire risk associated with these targets is taken under consideration through the definition 

and possible quantification of appropriate risk metrics. 

5.3.2 Proposed path to quantify Step 2: Target vulnerability criteria estimation 

5.3.2.1 Description of the target vulnerability criteria estimation step and corresponding path of action 

In Step 1 of the new PBFPD process, FPEs collected the targets which contribute to the system overall performance. 

Then, in Step 2, for each considered targets, FPEs have to quantify how these targets are affected by both direct and 

indirect effects of fire events, events involving a fire and defined between two "chronic" states of the system. 

As the new engineering process is target oriented, it is essential to get the metrics allowing the estimation of the 

potential vulnerability of the targets. Vulnerability criteria metrics would have to include: 

- Typical criteria related to fire impacts to humans (due to thermal threat, toxic threat and loss of visibility which 

impedes evacuation), 

- Vulnerability criteria related to evacuation behaviors, 

- Vulnerability criteria related to indirect fire threat to people, 

- Vulnerability criteria related to safety equipment, building contents (e.g. for heritage preservation) and 

- Vulnerability criteria related to the use of fire protection measures (sprinkler, fire fighting) on building contents 

and systems. 

These vulnerability criteria have to be collected and the process by which the damage is assessed has to be a result 

of an agreement within the scientific community not only involving fire protection engineers but also: 

- Toxicologists, psychologists, etc. when the targets are related to the life safety objective, 

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- Operators, electronics engineers, etc. when the targets are related to the business continuity objective, 

- Structural engineers, etc. when the targets are related to the property protection objective. 

The corresponding path to quantify the target vulnerability criteria estimation step of the PBFPD process is 

illustrated in Fig. 5-8, and detailed in the following paragraphs. 

Guideline Standard level for 

vulnerability criteria of 

human/equipment/structures 

in case of fire event 

Research for vulnerability 

criteria of 

human/equipment/structures 

in case of fire event 

Target vulnerability criteria 

estimation 

Input from building owners, users and Output for fire effects tool / evacuation tool / 

designers, to determine a list of targets by structural tool developers and users building-occupant systems 

Fig. 5-8. Proposed path to target vulnerability criteria estimation 

5.3.2.2 Research to be carried out for estimating vulnerability criteria 

Methods of determining vulnerability criteria metrics as well as collecting and assessing collegially validated 

"technical" values to these criteria differ from the "performance criteria" presented in current PBFPD processes 

where they are prescribed by regulations or established via a political agreement among the project stakeholders. 

These prescribed values do not present the rationale behind them so it is quite difficult to validate their application to 

specific "building-occupant" systems (Cf. Chapter 2 of this dissertation). 

Concerning the role of the stakeholders in that matter in the proposed PBFPD process, it should be noted that 

building owners and users are still actively consulted in this Step research as they are the most involved parties to 

determine the nature of the targets present in their "building-occupant" systems. Standards such as the one from ISO 

TC92 / SC3 [18] would contribute both the needed data and the worldwide consensus for human targets under fire Climbing the Research to Application / Regulatory ladder

Input from toxicologists, psychologists, 

operators, electronics engineers, 

structural engineers... 

Standards, guides and guidelines 

already published or in progress 

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threat. The input from building designers is also required, from the research stage to the guideline/standard final 

stage, in order to define the users' domain of application. It should be noted that some output from this task research 

could be sent to fire effects tool / evacuation tool / structural tool developers and users in order for them to get the 

target vulnerability criteria metrics considered in the tools. 

5.3.2.3	 Establishing guidelines or standards for assessing vulnerability criteria of human/equipment/structures 

in case of fire events 

As mentioned above, vulnerability criteria are engineering values, collected from experiments and models. Fires in 

structures generate heat, toxic and irritant products, lower visibility, damage the structure which can lead to falling 

objects over escaping building occupants and emergency responders. Building occupants are very different 

populations across the building occupancy spectrum [9] and they are also different from the emergency responders 

in terms of how they can withstand a fire event. Due to the complexity of these phenomena to take into 

consideration, it seems that the first tasks to perform to create guidelines or standards are: 

- To look at defined "building-occupant" systems and collect the targets which are considered by the 

corresponding interested parties or stakeholders, in terms of nature (i.e. occupants, piece of equipments, 

contents, etc.) and distribution (e.g. percentage of population easily affected by fire effects due to heath status); 

- To analyze the possible ways of damaging these targets, during the fire event and in both short term and long 

term periods; 

- To quantify these damages and the reaction of the different targets in terms of activity loss affecting the overall 

performance of the system. 

5.3.2.4	 Using the guidelines for performing Step 2 in a PBFPD process 

While assessing the performance of a "building-occupant" system, the fire protection engineer will use the 

guidelines designed for Step 2 "target vulnerability criteria estimation" in order to determine the nature of the 

criteria (metrics determination) and to use validated values of these criteria that are relevant to the examined system 

(metrics evaluation). 

5.3.3 Proposed path to quantify Step 3: Fire risk analysis (quantification of the likelihood) 

5.3.3.1	 Description of the fire risk analysis (quantification of the likelihood) step and corresponding path of 

action 

In a deterministic approach, the current PBFPD processes do not specify detailed procedures on how to select fire 

design scenarios or they provide a list from where the FPE and the stakeholders can "pick up" and finally agree on 

the ones to use. Thus, the resulting fire design scenarios fell to consider the chronic use of a building, are focused on 

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the fire event instead of being target oriented and miss the importance of the recovery phase. In this step of the 

proposed PBFPD process, event trees are elaborated in order to describe quantitatively the different fire scenarios, 

not only characterizing the events between ignition and extinguishment, but also including the procedures to go back 

to a new "chronic" state of the "building-occupant" system. Fault trees are also established in order to characterize 

all the different scenarios leading to target damage, so as to capture the indirect threats to the targets. Fire risk 

models are used in this process step to help calculate the scenario likelihoods. 

Because the fire safety analysis is target oriented, input from designers is required to define the targets to protect 

from fire threat, the definition of the "functional zones", support systems, etc., as well as the possible relationships 

between the building occupants and the systems (i.e. life supporting systems for patients in Intensive Care Units in 

hospitals). Quantification of the trees notably requires ignition frequencies defined by functional zones of interest as 

well as the reliability records of the fire prevention and protection measures, also called "safety barriers" in this 

process. Analysis of past events, including investigations of major events would be collected and made available in a 

database. Life safety being a common objective among all stakeholders, this analysis is aimed at providing in fine 

detail guidance so that when using the proposed PBFPD process, a FPE would use this guidance to demonstrate that 

a considered project would have the adequate barriers to prevent such life-threatening events from occurring with 

the lowest probability practically achievable. Once this database is detailed enough and this analysis is done for lifethreatening events, regulators could set up this value (or class) of probability, which could become an upfront 

performance criteria at the start of the PBFPD process. 

Besides, it is also expected that an output of this task research would be dedicated to implement building safety 

documentation, with at least the effects and the maintenance of the most important fire protection measures called 

"safety barriers". 

The corresponding path relative to the PBFPD process step quantifying the impacts of fire events is illustrated in 

Fig. 5-9, and detailed in the following paragraphs. 

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Guideline or standard level 

for defining fire scenarios for 

building-occupant systems 

Research for 

defining fire scenarios for 

building-occupant systems 

Fire risk analysis 

(quantification of the 

likelihood) 

Input from designers to get the list of targets Output for documentation – most important safety to protect, the definition of the "functional barriers zones", etc., as well as the possible 

relationships between building occupants 

and building components 

Fig. 5-9. Proposed path to the quantification of the likelihood of fire events 

5.3.3.2 Research to be carried out for the process step related to the quantification of the likelihood of fire events 

Table 5-3 below is an example of data presented in the NFPA reports of US fires in selected occupancies [8]. This 

data categorizes the number of casualties and injuries as well as the direct property damage for different extents of 

flame damage. A discrepancy appears between the fires that are related to the life safety objective as their maximum 

extent is the room of fire origin and the fires that are related to the property damage objective as the more the fire 

extents, the more damage it causes, which could indicate that the design fire scenarios for the life safety objective 

may not be the same for other business or property oriented objectives [9].This information reinforces the fact that 

the fire risk analysis needs to be target oriented in order to determine the appropriate scenarios for each of the 

considered targets relevant to the different stakeholders. Climbing the Research to Application / Regulatory ladder

Event tree & fault tree analysis, both 

target oriented and fire protection 

measure treated as a safety barrier 

Database for "worst case" scenarios for 

building-occupant systems 

Analysis of fire statistics and past events 

by building-occupant systems, focused 

on targets and "functional zones" 

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Table 5-3. Structure Fires in Health Care Facilities, Excluding Nursing Homes by Extent of Flame Damage [8] 

Extent of Flame Damage Fires Civilian 

Deaths 

Civilian 

Injuries 

Direct Property 

Damage (in 

Millions) 

Confined or contained fire 560 18% 0 0% 8 9% $0.1 0% 

Confined to object of origin 1,930 61% 0 0% 29 33% $3.8 18% 

Confined to room of origin 510 16% 1 100% 44 51% $4.2 20% 

Confined to floor of origin 60 2% 0 0% 1 1% $2.1 10% 

Confined to building of origin 90 3% 0 0% 5 6% $10.3 49% 

Extended beyond building of origin 10 0% 0 0% 0 0% $0.7 3% 

Total 3,150 100% 1 100% 87 100% $21.3 100% 

5.3.3.3 Establishing guidelines or standards for assessing the quantification of the likelihood of fire events 

Step 3 guidelines will be established for specific "building-occupant" systems, and more precisely for the different 

targets considered by the stakeholders when defining the performance of the systems, as the risk analysis is targetoriented in this study paradigm. They will contain results from fault tree analysis, where the outcomes would be 

presented, not only with the evaluation of the fire scenario likelihoods, but also with the degree with which the 

different targets are affected by the fire scenarios. Scenario grouping or scenario clustering have been considered in 

the current PBFPD processes in order to have a manageable set of scenarios which could represent most of the 

possible fire scenarios which could occur in a considered project. Nevertheless, this grouping is still achieved 

project by project and it still requires the agreement of the different stakeholders. 

Concerning industrial facilities, Barry [19] proposes different ways to group or cluster scenarios. The categories 

listed below have been adapted from industrial facilities to common buildings: 

- by exposure category, considering categories such as localized exposure, moderate exposure (limited to a 

defined area) and major exposure (large effect zone). It should be noted that NFPA also provides fire statistics 

by exposure categories, as presented in Table 5-3 of this chapter, 

- by contributing factor breakdown to the fire events, considering "failures" or "potential weak links such as 

human error", failures of fire protection technical measures (automatic detector, automatic fire suppression 

system...) or failures of fire protection managerial measures (locked egress doors...). This categorization could 

be valuable when assessing the most important fire protection measures for a considered "building-occupant" 

system, 

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- by hazard. In industrial plants, there are more issues than just the fire hazard to consider (explosion, release of 

toxic material). In common buildings, and in the present research, fire is the only hazard to be considered. This 

categorization could be used when different types of technological hazards are examined for "buildingoccupant" systems. 

As within this "building-occupant" system paradigm, the risk analysis is target oriented, fault trees would also be 

considered in order to determinate not only the direct effects of fire events on targets but also the indirect effects of 

fire events (e.g., fires affecting life support system of a patient in an intensive care unit but not spreading in the 

vicinity of the patient). 

A possible outcome for the guidelines to be established for assessing the quantification of the likelihood of fire 

scenarios would be the creation of databases for "worst case" scenarios for specific "building-occupant" systems, 

based on relevant investigation reports. 

5.3.3.4 Using the guidelines for performing Step 3 in a PBFPD process 

These guidelines are linked to a database of investigation reports on catastrophic fire events that happened in 

systems similar to the one examined by the fire protection engineer so the FPE can verify the examined system is 

provided with safety barriers which would prevent such catastrophic events from occurring in it. The fire protection 

engineer also uses the guidelines to select fire protection measure sets which are able to maintain the overall 

performance of the studied "building-occupant" system, as high as possible during fire events. 

5.3.4 Proposed path to quantify Step 4: Fire risk analysis (quantification of the impacts) 

5.3.4.1 Description of the fire risk analysis (quantification of the impacts) step and corresponding path of action 

Current PBFPD processes include or reference calculation methods or tools that can be used to assess the 

consequences of the fire, with an emphasis on the estimation of the fire effects. Challenges related to the use of tools 

notably arise from the lack of validation of these tools, the "user effect" and the availability and estimation of the 

input data for all these tools. In this step of the proposed PBFPD process, fire effects tools, evacuation tools, 

structural response tools are used to estimate the consequences of fire scenarios for the considered targets. In spite of 

the tremendous amount of research and development related to the tools, they remain research tools and the results 

applied to fire engineering still nowadays require some engineering judgment. Use of engineering judgment will 

never go away. However, it is proposed that better guidance can be developed to help provide better uniformity in 

application and engineering analysis. To address this, it has been decided to create a 'test bed' environment in order 

to assess the appropriateness of engineering tools to be used for a given application. This environment, which 

implies the participation, not only of researchers who develop the tools, practitioners who apply them in an 

engineering environment, but also academia who can perform long term studies and stakeholders who are concerned 

by the validity of the tools to solve the engineering problems. 

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The corresponding path relative to the PBFPD process step quantifying the impacts of fire events is illustrated in 

Fig. 5-10, and detailed in the following paragraphs. Climbing the Research to Application / Regulatory ladder

of fire scenarios for defined 

building-occupant systems 

Human behavior database, 

structural response database, 

fire risk database 

Guidelines for using appropriate tools for assessing 

Guideline for assessing the the consequences 

appropriateness of tools to be 

used for a given FPE 

application 

'Test bed' environment to 

assess the appropriateness of 

engineering tools to be used 

for a given application 

Fire risk analysis 

(quantification of the 

impacts) 

Databases for 

Fire Protection 

Engineering 

applications 

Combustible packages (heat 

release rate, fire effluent 

production) 

Input from regulators, fire 

protection engineers and 

Output for tools developers to get needed functionalities building designers to establish
 

case studies, use same building
 and match at best validation domain with usage domain 

configurations and share tool use 

knowledge 

Fig. 5-10. Proposed path to the quantification of the impacts of fire events 

5.3.4.2 Research to be carried out for the process step related to the quantification of fire events consequences 

In the last two decades, fire research has made tremendous advances in elaborating models and providing tools 

which have helped the FPEs estimate the consequences of fires. At the same time, more tools became available for 

the FPEs to assess the evacuation process of building occupants. 

Within Step 4 of the proposed PBFPD process, a coordinated action is proposed for assessing the appropriateness of 

engineering tools to be used for given applications, i.e. FPEs quantify the impacts of fire scenarios for specific 

"building-occupant" systems with tools validated for the domain characterized by these systems. This action 

involves the creation of 'test bed' environments where regulators, fire protection engineers and building designers 

establish case studies, use same building configurations and share tool use knowledge. More detailed explanations 

regarding the "test bed" environments are presented in [20,21]. 

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It should be noted, that since not all of the necessary validated models and tools are ready for use, a possible output 

for tools developers from Step 4 research would be to get the functionalities needed by the users so as to match at 

best the tool validation domains with the tool usage domains. 

Data required for the use of these tools is also a major concern. Database structures for fire effect tools and human 

behaviors exist and they could be used and populated for the common good of all the fire protection engineering 

community, not looking for all possible data but specific data designed system by system. 

5.3.4.3	 Establishing guidelines or standards for assessing the quantification of fire event consequences 

Guidelines such as the ones published by SFPE [22], ASTM [23] and ISO [24] are important documents which help 

the fire protection engineer to demonstrate the appropriateness of a fire tool to be used for engineering purposes, 

describing how the tool validation process should be conducted. Nevertheless, these guidelines detail generic 

characteristics of the fire tools, such as particular fire phenomena: fire plume, fire spread or smoke transport while 

leaving the application side completely at the hands of the user of these guides. These documents have to be 

considered as a first step towards a more comprehensive and more coherent use of fire tools in the engineering 

community. Nevertheless, they still need to be completed with other guidelines which are application oriented that is 

to say guidelines which are not generic but are really applied to specific "building-occupant" systems. 

These guidelines for the new PBFPD process will be centered around the application and they will concern all the 

tools which can potentially be used to solve the engineering problem, not only the ones dedicated to fire effects 

quantifications, but also evacuation process and response of the structures. 

5.3.4.4	 Using the guidelines for performing Step 4 in a PBFPD process 

Once established for considered "building-occupant" systems, the guidelines for assessing the quantification of fire 

scenarios consequences are used by FPEs to help in the selection of the most appropriate tools to use, in conjunction 

with databases containing relevant values of input data for the tools. FPEs also use the guidelines to assess the effect 

of trial fire protection measure sets on the overall performance of the studied "building-occupant" system. 

5.3.5 Proposed path to quantify Step 5: Evaluation of the integration of the fire protection measures in the system 

5.3.5.1	 Description of the step relative to the evaluation of the integration of the fire protection measures in the 

system and corresponding path of action 

In the current SFPE conceptual design procedure for fire protection design [25], the evaluation of the integration of 

the fire protection measures in the system comes after the final trial design has been selected by the stakeholders and 

in a form of a testing plan including commissioning and acceptance testing and an Operation and Maintenance 

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manual. SFPE indicates that "during the design development and construction document phases, the conceptual 

designs evolve into detailed designs of systems and the plans and specifications that will be used for bidding and 

constructing the building. The design development and construction documentation are not described in [its] guide. 

However, guidance for the coordination of design documentation is given in chapter 12 [of its guide]". SFPE also 

indicates that "coordination between disciplines is critical during these phases in order to ensure proper interaction 

between systems". 

The 2005 edition of the International Fire Engineering guidelines (IFEG) [26] includes paragraph 1.2.13 which 

states that "real-life safety over ensuing decades will be highly dependent on elements other than the approved 

design", such as construction, commissioning, management and use, and maintenance. IFEG differ from the SFPE 

guide [25] as they include these elements into the design brief (which they call the Fire Engineering Brief, FEB). In 

paragraph 1.2.13 of IFEG, it is mentioned that "the FEB should access any tangible measures addressing the 

question of how high, or how low, one can prudently expect standards for the above elements to be maintained over 

the life of the building". Nevertheless, it should be noted that IFEG do not provide more insight on how these 

elements should be determined, quantified and included in the overall process. Besides, when looking at Figure 1.3.2 

of IFEG describing the analysis of trial designs, the incorporation of the elements established in its paragraph 1.2.13 

only affect the final report, as is the case with the SFPE guidelines. 

A challenge related to the application of current PBFPD processes concerns the difference in the fire safety provided 

by fire protection measures between the conceptual design phase and the reality of the building use has been 

partially taken into consideration by adding redundancies in the fire protection measures as illustrated in Fig. 5-11. 

Nevertheless, this challenge is amplified by the aforementioned "disconnection" between the fire protection 

measures and the rest of the "building-occupant" system, not only in terms of technical measures but also in terms of 

managerial measures. 

Fire safety level code / guidelines 

real 

minimum 

DesignConstruction/executionAdministrationMaintenance

Redundancies 

Fig. 5-11. Levels of fire safety as a function of building phases and the introduction of redundant fire protection 

measures, adapted from [27] 

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In the new PBFPD process, Step 5 relative to the evaluation of the integration of the fire protection measures in the 

system has to be done in order to be sure that the installation of these fire protection measures which are used for 

emergency situations are not counter-productive in the everyday use of the building. A feedback loop will be 

instituted for each fire protection measures or for sets of fire protection measures. This 5th important technical step is 

performed because of the challenges related to the maintenance and the possible changes of the building use once 

the design phase and the construction phase are completed (Cf. Chapter 2 of this dissertation). 

The corresponding path relative to the PBFPD process step evaluating the integration of the fire protection measures 

into the system is illustrated in Fig. 5-12, and detailed in the following paragraphs. 

Feedback loop to insure that the fire 

protection features are not 

counterproductive for the system
 

Input from existing contingency plans for Output for updated management plans, fire risk 

building-occupant systems analysis 

Guideline for evaluating the 

integration of the fire 

protection measures in the 

system 

Research for evaluating the 

integration of the fire 

protection measures in the 

system 

Evaluation of the integration 

of the fire protection 

measures in the system 

Climbing the Research to

Application / Regulatory ladder

Assessment of enforcement process of 

fire protection measures installed in 

building-occupant systems 

Fig. 5-12. Proposed path to the Evaluation of the integration of the fire protection measures in the system 

5.3.5.2	 Research to be carried out for the process step related to the evaluation of the integration of the fire 

protection measures in the system 

Because the paradigm of study shifted from the fire event to the study of the effects of fire as a disruptive event of a 

"building-occupant" system, input from existing contingency plans are examined in order to verify that their own 

safety measures are not in contradiction with the proposed fire protection measures to be installed. Maximization of 

potential uses of the same measures dealing with different types of disruptive events or even "chronic" uses of the 

building can also be assessed in this process step. 

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Care will be taken in the associated documentation for the stakeholders so as to point them to the parameters of the 

fire scenarios that should remain under a certain range under pain of leading to a "worst case" scenario event. This 

integration or lack of, fire protection measures will then help the FPE focus on these particular parameters so the 

building owner, manager and occupants are required to keep them within a certain range. Interconnection is also 

made with the quantification of fire risk analysis: a sensitivity analysis should be performed for the most important 

parameters or sets of parameters in order to notably avoid the “worst case” scenarios from happening with a higher 

frequency. 

5.3.5.3	 Establishing guidelines or standards for assessing the integration of fire protection measures in a 

considered "building-occupant" system 

One important foreseen output of the guidelines or standards related to the assessment of the integration of fire 

protection measures in a considered "building-occupant" system concerns the assessment of the enforcement process 

of these fire protection measures. The prescriptive requirements will also have their enforcement assessed this way, 

in a similar way Tsujimoto [15] looked at the effects of the installation of sprinklers in patient room in Japanese 

hospitals (cf. § 5.3.1.2 of this chapter) on fire casualties. 

5.3.5.4	 Using the guidelines for performing Step 5 in a PBFPD process 

The output of this step is also an essential document for the different stakeholders concerning the possible 

interactions of the fire protection measures and the other components of the considered "building-occupant" system. 

5.3.6 Proposed path to quantify Step 6: cost benefit analysis 

5.3.6.1	 Description of the cost-benefit analysis step and corresponding path of action 

This step is carried out in order to assess the cost associated with implementing fire protection measures in the 

"building-occupant" system. Once again, the separation of the different "building-occupant" systems would make it 

easier to integrate the results of this cost-benefit analysis, considering these impacts would be different when 

looking at the same fire protection measure for a small new building, a small extension of a large building or a large 

new building (as illustrated by Charters and Ramachandran [28] about sprinklers in schools). 

The corresponding path relative to the PBFPD process step performing the cost-benefit analysis of the fire 

protection measures into the system is illustrated in Fig. 5-13, and detailed in the following paragraphs. 

105 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Climbing the Research to

Application / Regulatory

ladder 

Guidelines for assessing the costs of 

managerial procedures in addition to the 

costs of installation and maintenance of 

technical fire protection measures 

Guideline for evaluating the 

cost of integration of the fire 

protection measures in the 

system 

Research for evaluating the 

cost of integration of the fire 

protection measures in the 

system 

Cost benefit analysis 

Input from economists to help about the 

use of different economics methods 

Fig. 5-13. Proposed path to the cost-benefit analysis of the trial designs 

5.3.6.2 Research to be carried out for the process step related to fire protection measures cost benefit analysis 

As research concerning the determination of the target vulnerability criteria (Step 2) requires the help from experts 

in toxicology, psychology, electronic engineers or structural engineers, this process step also requires a consequent 

input from experts outside of the fire protection engineering field: economists. 

5.3.6.3 Establishing guidelines or standards for fire protection measures cost benefit analysis 

For the process step related to the evaluation of the costs and benefits of fire protection measures proposed to be 

installed and maintained in well defined "building-occupant" systems, guidelines will be established to include the 

assessment of managerial procedure costs in addition to the costs associated with technical fire protection measures. 

5.3.6.4 Using the guidelines for performing Step 6 in a PBFPD process 

The output of this step is also an essential document for the different stakeholders concerning the costs and the 

benefits of installing and maintaining the fire protection measures proposed as a results of the fire risk analysis steps 

(Step 3 and Step 4) along with the document related to the integration of these fire protection measures into the 

"building-occupant" system, in the study paradigm. 

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5.4 Conclusions for this chapter 

In order to overcome the shortcomings and challenges related to the application of current performance-based fire 

protection design (PBFPD) processes, a new PBFPD process has been developed within a "building-occupant" 

system paradigm. 

Although the technical steps of the new process have been defined, guidance relative to the application of these steps 

still require research as well as the establishment of guidance specific to "building-occupant" systems. 

This chapter detailed the actions fire protection engineers would be required to perform for each of the six technical 

steps of the new risk-informed PBFPD process and how these actions are similar to or different from the ones 

performed in the current PBFPD processes. For each step of the process, a plan of action has been proposed in order 

to describe the nature of the information that would be inscribed in the future guidance, and how this information 

would become a part of future guidelines and standards. Useful elements of information extracted from past and 

current research involving experts from a large spectrum of competencies and the systems stakeholders, as well as 

information from standardization efforts were presented for each step. 

References 

1.	 J. Taveau, Risk assessment and land-use planning regulations in France following the AZF disaster, Journal of 

Loss Prevention in the Process Industries, Volume 23, issue 6, (2010) 813-823 

2.	 U.S. Nuclear Regulatory Commission (2007), Verification and Validation of Selected Fire Models for Nuclear 

Power Plant Applications – (NUREG-1824, EPRI 1011999) Volume 1: Main Report, U.S. Nuclear Regulatory 

Commission and Electric Power Research Institute, 2007 

3.	 NFPA 805, Performance-Based Standard for Fire Protection for Light Water Reactor Electric Generating 

Plants, 2010 

4.	 NFPA 99, Health Care Facilities Code, 2012 

5.	 SFPE, SFPE Code Official's Guide to Performance-Based Design Review, Society of Fire Protection Engineers 

– International Code Council, June 2003 

6.	 M.J. Karter, Jr., Fire Loss in the United States during 2011, National Fire Protection Association, September 

2012 (available at: http://www.nfpa.org/assets/files/PDF/OS.fireloss.pdf) 

7.	 U.S. Fire Administration/National Fire Data Center, Fire in the United States2003-2007, Fifteenth Edition, 

October2009 

8.	 M.Ahrens, Selections from the U.S. Fires in Selected Occupancies – Health Care Facilities, excluding Nursing 

Homes, National Fire Protection Association, Quincy, MA (USA), March 2006 

9.	 A. Alvarez, B.J. Meacham, Towards an Integrated Performance-Based Design Approach for Life Safety Across 

Different Building Use Groups, in: Proceedings of the 12th International Interflam Conference, Nottingham, 

UK, 2010 

10.	 J.R. Thomas, "The use of fire statistics in guiding research and code development", Interflam 2007, proceedings 

of the eleventh conference, volume 2, pp. 1139-1147, Interscience Communications, London (UK), 2007, also 

107 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

available as: J.R. Thomas, "The use of fire statistics in guiding research and code development", NRCC-49243, 

National Research Council Canada, 2007 

11.	 M Salisbury, P Johnson, E. Yii and M.C. Hui, "QRA and fire safety – a beneficial experience...", Interflam 

2007, proceedings of the eleventh conference, volume 2, pp. 1253-1263, Interscience Communications, London 

(UK), 2007 

12.	 R. Fahy, Available Data and Input Into Models, chapter 4.3 of the "Workshop on Building Occupant Movement 

During Fire Emergencies, June 10-11, 2004, National Institute of Standards and Technology", NIST Special 

Publication 1032, NIST, March 2005 

13.	 K. Tillander, "Utilisation of statistics to assess fire risks in buildings", VTT publication 537, VTT Technical 

Research Centre of Finland, 2004 (available at: www.vtt.fi/inf/pdf/publications/2004/P537.pdf) 

14.	 Y. Kobayashi and H. Nozaki, A Statistical Method to Evaluate Fire Risks in Non-Residential Buildings in 

Japan," in: Fire Safety Science: Proceedings of the Eight International Symposium, China, International 

Association for Fire Safety Science, 2005, pp. 341-352 

15.	 M. Tsujimoto, Death Risk by Building Fires in Japan and its Usage, Fire Science and Technology, vol. 23, 

no. 4, 2004, pp. 304-311 

16.	 ISO/TR 16732-1:2012, Fire Risk Assessment 

17.	 NFPA 557, Standard for the determination of fire loads for use in structural fire protection design, 2012 

18.	 ISO/DIS 13571, Life-threatening components of fire — Guidelines for the estimation of time to compromised 

tenability in fires, revision of first edition ISO 13571:2007, 2011 

19.	 T. F. Barry, Risk-Informed, Performance-Based Industrial Fire Protection, TFBarry Publications, Tennessee 

Valley Publishing, 2002 

20.	 A. Alvarez and B.J. Meacham, "Ready-to-use" Building Layouts and Combustible Packages for 3-D 

simulations, proceedings of the Fire and Evacuation Modeling Technical Conference, 2011 

21.	 A. Alvarez and B.J. Meacham, 'Test bed' environment process for assessing the appropriateness of engineering 

tools to be used in performance-based design applications, in: Proceedings of the 9th International Conference 

on Performance-Based Codes and Fire Safety Design Methods, Hong Kong. 20-22 June 2012 

22.	 SFPE, SFPE Engineering Guide – Guidelines for Substantiating a Fire Model for a Given Application, SFPE 

G.06.2011, Society of Fire Protection Engineers, 2011 

23.	 ASTM E1591-07, Standard Guide for Obtaining Data for Deterministic Fire Models, American Society for 

Testing and Materials, 2007 

24.	 ISO16730:2008, Fire safety engineering -- Assessment, verification and validation of calculation methods 

25.	 SFPE, SFPE Engineering Guide to Performance-Based Fire Protection, 2nd edition, Society of Fire Protection 

Engineers, 2007 

26.	 IFEG, International Fire Engineering Guidelines, Australian Building Codes Board, Department of Building 

and Housing (New Zealand), International Code Council (USA), and National Research Council (Canada), 

2005 edition 

27.	 V. Stenstad and W.R. Bjørkmann, A Systematic Approach to Fire Safety Design, in: Proceedings of the 5th 

International Conference on Performance-Based Codes and Fire Safety Design Methods, 6-8 October 2004, 

Society of Fire Protection Engineers, 2004, pp. 67-78 

28.	 D. A. Charters and G. Ramachandran. Quantitative Risk Assessment in Fire Safety. Spon Press, 2011 

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6. CONCLUSIONS: MAIN OUTCOMES 

The research presented in this dissertation is aimed at establishing the next generation of performance-based fire 

protection design (PBFPD). It originated from the fact that despite being in use for more than 20 years, the 

application of PBFPD remains limited, several shortcomings exist, and an increasing number of countries are 

moving toward ‘prescribed performance’ to address the gaps. There are many contributing factors. Research has 

been carried out in two principal areas: the relationship between occupants and fire safety measures in the contexts 

of holistic building performance expectations and the everyday use of the building, and into the lack of specifics 

within current PBFPD approaches. 

This conceptual research, carried out in a paradigm centered around systems defined by building types and their 

associated occupants, led to the establishment of a functional new PBFPD process which would require all the actors 

involved in its application to shift to this system based paradigm from the current one related to the design of fire 

protection measures. Guidelines required to use the new process, for each of its steps and for relevant systems, were 

not established during this Ph.D. as they would require many years of research and development. Nevertheless, a 

plan of action dedicated to their establishment has been presented in this dissertation. 

The main outcomes of the research are presented below: 

- A review of two decades of application of PBFPD processes highlights challenges in applying these current 

processes both at technical and political levels. Challenges still exist concerning the definition/quantification of 

the strategic elements of any PBFPD process: the performance criteria (which current denomination should be 

changed to "fire effect criteria"), design fire scenarios, and the use of tools to quantify the trial designs. 

- Despite efforts made to consolidate databases gathering information related to buildings, fires and occupant 

behaviors, it is still necessary to make such databases available to the whole engineering community. Besides, 

validation and verification domains related to the tools still need to be defined according to the engineering 

problems these tools are used to solve. 

- A "building-occupant" system has been defined, along with its main characteristics: "Targets" are the system 

agents responsible for the system daily performance (building occupants and components). During normal every 

day conditions or "chronic states of the system", they are located in "functional zones" where they carry out 

their activities associated with "chronic objectives", established in accordance with the system scope and 

performance. "Utility zones" include system support components such as electricity, HVAC and plumbing. 

"Disruptive events", such as fires, have to be considered between two consecutive "chronic states". In order to 

mitigate the "event effects" on the system performance, "acute objectives" have to be set up so to take into 

consideration "direct effects" and "indirect effects" with which the disruptive events can possibly damage the 

targets. 

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- The performance of a building is related to objectives set up for the normal use of the building and it is 

important to quantify how disruptive events can affect this performance. 

- A building design agreed among different stakeholders covers many and sometimes competing objectives, not 

only dealing with normal building uses, but also during disruptive events. 

- There is a need for a system approach to assess the overall building performance in order to prevent some 

installed building components being ignored or misused by the building occupants, especially during emergency 

situations. 

- Within the "building-occupant" system paradigm, a risk-informed system specific performance-based approach 

has been established in order to quantify the effects of disruptive events on the overall building performance 

and to help verify that the protection measures installed in the system formed by precise building types and their 

associated occupants are well integrated in this system. 

- The aforementioned system specific process was applied to deal with fire disruptive events, that is to say to 

quantify the effects of fire events on the overall performance of the system. The main difference between the 

current PBFPD processes and the new one is related to their respective problem definition: the current processes 

are focused on the design of fire protection measures that would mitigate the effects of fire scenarios defined 

between ignition and extinguishment while the new process is aimed to assess how fire protection measures, as 

an integrated component of the system, would help mitigate the effects of fire events, including the recovery 

period of the system. 

- Being focused on the system, a fire risk analysis is performed centered on the study of the actors of the system 

in their everyday performance and how fire protection measures can mitigate the effects of fire events on this 

everyday performance. Besides, the new PBFPD process contains a technical stage dedicated to the evaluation 

of the integration into the system of the fire protection measures, selected after the fire risk analysis. A costbenefit analysis finalizes the technical part of the process which has been performed independently and in a 

straightforward manner by fire protection engineers (FPEs). At the end of this technical part, FPEs have 

elaborated three documents detailing the results of the fire risk analysis, of the evaluation of the integration of 

the fire protection measures into the system and of the cost-benefit analysis. Based upon these documents, the 

stakeholders decide which fire protection measures they would have installed in their system. This process is 

then demonstrating a complete separation between the "political" decision-making process and the "technical" 

resolution of the engineering fire problem. As a consequence of this separation, the technical stage of the 

process becomes transparent, both for stakeholders who establish the performance targets (political decision) 

and for the engineers in charge of the evaluation of the disruptive effects on the system performance (technical 

analysis); 

- As a proof of concept, it has been shown through text and examples how the new framework addressed the 

challenges with the existing approaches, operated within a more holistic "building-occupant" system paradigm, 

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illustrated how viewing fire as a perturbation within the larger "building-occupant" system would increase fire 

safety performance over the life of a building, and deliver a higher level of building fire safety performance. 

- It is important to include the "building-occupant" system stakeholders not only in the making of the guidelines 

for each technical step of the proposed process, but also in the research process itself, as these stakeholders 

know the particularities of their systems; 

- Multiple iterations would be required in order to establish the guidelines as the process steps are dependant in 

terms of input-output; 

- Research for the different steps would require more or less time and resources, as well as the participation of 

engineers from disciplines other than fire protection engineers; 

- Technical literature contents (including engineering tools and input data), as well as standards and codes 

relative to the different technical steps of the process would have to be examined and applied to specific 

"building-occupant" systems. Collections and examination of the past studies are still relevant even if the data 

might require to be updated (e.g. walking speed values were established in the last 1980's and pieces of furniture 

in the NIST furniture calorimeter experiments may be outdated as materials have evolved since then). 

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7. FUTURE WORK 

The future work is aimed at the establishment of guidelines, specific to "building-occupant" systems and in 

elaborating each technical step of the proposed PBFPD process. One can imagine the difficulty in managing the 

development of guidelines for all the steps, for all the possible "building-occupant" systems: 

- interactions between these steps have to be examined and assessed, 

- the research needed for each step guideline is currently at different level. 

In consequence, there is a need for coordination of all the efforts as well as a repository of the information gathered 

for each step, from the initial research gathering, to its analysis and to the establishment of the corresponding 

guidelines. 

Such an environment which facilitates this coordination and stores the guideline development has been created in 

the form of a web-platform. The original idea of a web-platform was associated with the 'test bed' environments for 

fire effects tools as presented in Appendix A2. Along with the objective of performing studies to assess the 

appropriateness of tools to be used for performance-based applications, this first version of the web-platform was 

also intended to contain databases for "fuel packages" ready to use in 3-D simulations. 

The development of this original web-platform was put on hold as the research presented in this Ph.D. dissertation 

was carried out. As the new PBFPD process was elaborated with its six different technical steps, it was found that 

the structure of the original web-platform could be used to facilitate the establishment of the process step guidelines 

and serve as a repository for input data. 

Indeed, each step can be perceived as an engineer step aimed at the quantification of important parameters required 

to solve the engineering problem: how to quantify and mitigate the effects of fire events on the overall performance 

of a considered "building-occupant" system? In other terms, each step would require the use of corresponding tools, 

supplied with the input data needed to use these tools, in order to solve a specific step issue for a considered 

"building-occupant" system (Fig. 7-1). The latter part, solving a specific step issue for a considered "buildingoccupant" system, is precisely why the 'test bed' environments were created in the first place. 

Process Technical Step 

Tools Input Data 

'Test bed' 

environment 

Fig. 7-1. Interconnections between tools, input data and 'test bed' environments 

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It should be noted that tools related to the "Target Vulnerability Criteria Estimation" Step are not primarily about 

using engineering tools but mostly using data established by specialists such as: 

- toxicologists, clinicians and psychologists for assessing threshold damaging fire effects on people, 

- material engineers and electronic engineers for assessing threshold damaging fire effects on valuable artifacts 

and pieces of equipment important for the system performance, 

- structural engineers for assessing threshold damaging fire effects on building structures. 

The importance of the use of 'test bed' environments is illustrated in a schematic way with the four following 

figures: Fig. 7-2. shows that different populations can be defined according to the buildings in which they are 

located. Due to the building configurations and contents, particular fire distributions can be determined for different 

types of buildings, as illustrated by Fig. 7-3. According to their characteristics, building occupants are more or less 

sensitive to the effects of a fire. Fig. 7-4. shows how the different populations could be more or less affected by the 

fire distributions established by building types. At last, Fig. 7-5. integrates the different domains linking buildings, 

their occupants and the types of fires that could occur in these buildings and it shows the importance of establishing 

'test bed' environments, in order to concentrate the efforts of tool developers to validate their tools in priority for the 

domains defined by the "building-occupant" systems. 

Occupants 

...

Population 4: teachers and pupils 

Population 3: adults... 

Schools 

Population 2: doctors, staff, patients 

Offices

Population 1: doctors, staff, patients 

HospitalsNursing homes

buildings 

Fig. 7-2. Occupant populations as a function of buildings 

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HospitalsNursing homes...OfficesSchools

buildings 

fires 

Fig. 7-3. Fire distributions as a function of buildings 

occupants 

Population 1: doctors, staff, patients 

Population 2: doctors, staff, patients 

Population 3: adults... 

Population 4: teachers and pupils 

fires 

Fig. 7-4. Effects of fire distributions on building occupant populations 

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Hospitals

Nursing homes 

...OfficesSchools

buildings 

occupants 

fires 

Validation domain for hospitals 

Validation domain for nursing homes 

Fig. 7-5.	 Validation domains for different "building-occupant" systems, in comparison with the physical domain 

of possibilities involving buildings, fires and occupants 

Future work will then consist in establishing relevant "building-occupant" systems and in communicating all their 

descriptive information to tool developers, as well as the important engineering issues related to each of these 

systems. 

It should be noted that some informative structure has been developed in recent years in order to aggregate in one 

place all the information related to a building. Indeed, some future work will be related to incorporating into the 

web-platform, information collected via the use of Building Information Modeling (BIM). The National Building 

Information Model Standard Project Committee defines BIM as: 

"Building Information Modeling (BIM) is a digital representation of physical and functional characteristics 

of a facility. A BIM is a shared knowledge resource for information about a facility forming a reliable basis 

for decisions during its life-cycle; defined as existing from earliest conception to demolition. 

A basic premise of BIM is collaboration by different stakeholders at different phases of the life cycle of a 

facility to insert, extract, update or modify information in the BIM to support and reflect the roles of that 

stakeholder." 

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Appendix A1
 

"Towards an Integrated Performance-Based Design Approach
 

for Life Safety Across Different Building Use Groups"
 

presented at the international conference "Interflam 2010"
 

Reprinted with permission of Interscience Communications Ltd, UK
 

Original source:
 

Alvarez, A. and Meacham, B.J., "Towards an Integrated Performance-Based Design Approach for Life Safety
 

Across Different Building Use Groups" in: Interflam2010: proceedings of the 12th international Fire Science &
 

Engineering Conference, East Midlands Conference Centre, University of Nottingham, UK, 5-7th July 2010,
 

Interscience Communications Ltd, UK, volume 2, pp. 1259-1270 - ISBN: 978-0-9556548-7-9 (set of 2 volumes)
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TOWARDS AN INTEGRATED PERFORMANCEBASED DESIGN APPROACH FOR LIFE SAFETY 

ACROSS DIFFERENT BUILDING USE GROUPS
 

Alberto ALVAREZ & Brian J. MEACHAM, Ph.D., P.E.
 

Worcester Polytechnic Institute, 100 Institute Road, MA 01609 (USA)
 (al_alvarez@wpi.edu)
 

INTRODUCTION 

A main advantage of Performance-based Design (PBD) approaches for fire safety is to allow 

for the engineering of design solutions that provide at least an equivalent means of protection to 

prescriptive building and fire code requirements, but without imposing undesired constraints on 

aspects of building design, such as design flexibility, innovation, or maximization of cost/benefit 

ratio. Another advantage of PBD approach is to consider multiple stakeholders' objectives: not only 

the life safety objective which is the primary objective of building codes, but also architectural and 

user objectives, as well as business interruption and property protection. Performance criteria 

established for each objective are the parameters used to evaluate the suitability of a PBD solution. 

Nevertheless, these parameters are not explicit and they need an agreement of the involved 

stakeholders. For life safety, performance criteria are associated with the assessment of fire effects on 

people, often in terms of threshold values of temperature, thermal radiation, toxicity, or visibility. This 

assessment is also based on design fire scenarios, which are developed upon representative design fire 

scenarios. These design fire scenarios also need the agreement of the different stakeholders. 

A range of guides, guidelines and standards have been developed in order to help the engineer 

(1-5) elaborate PBD solutions and the Authority Having Jurisdiction (AHJ) approve the final design . 

Even though these guidelines emphasize the importance of various parameters upon the acceptability 

of design solutions, they fail to provide a detailed framework for evaluating a specific building 

project, mainly because their scope of application is too broad. Known difficulties in achieving a 

homogeneous working framework for the engineer and the AHJ are related to, among others (6): 

- the definition of quantified acceptance criteria, 

- the selection of design fire scenarios, 

- the tools used to perform the fire consequence analysis, 

- the quantification of the most important parameters of the overall fire risk estimation. 

In considering the many challenges with PBD as currently carried out, a simple idea emerged based 

on the fact that fire safety requirements are defined in regulation according to the building occupancy 

use: PBD solutions should address the intent of the issues embodied in the prescriptive regulations. 

Since existing PBD guidelines have already introduced the importance of building and occupant 

characteristics to PBD solutions, albeit without quantifying that importance, a next logical step is to 

develop more specific PBD guidance around these characteristics, drawing upon supplemental data 

for the PBD analysis from operational and loss experience. This paper outlines the concept of an 

integrated approach to PBD that is based around building use groups and focused on life safety. 

BREAKING DOWN A COMPLEX TRIPARTITE HETEROGENEOUS FRAMEWORK 

Developing a good building fire safety design requires appropriate consideration of the interaction 

between the building, the people who occupy it, and the fire and its effects (Fig. 1). At present, this 

concept is embodied in existing guidance documents in a rather generic manner, asking engineers to 

consider building characteristics, occupant characteristics and fire characteristics. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Building People

Fire

Materials

Construction

Accessibility

Aesthetics Use

Comfort

Function

Geometry

Behavior

Response

Affiliation

Abilities

Physiology

Decisions

Sources of ignition

Fuel type, load, 

arrangement

Ventilation

FP Systems Figure 1. Building life safety design framework related to fire event 

Since most of the current guidelines are rather generic, a gap exists in that critical differences between 

configurations found in assemblies, offices, hospitals and so forth are not necessarily addressed. More 

detailed guidance would be helpful, but it is difficult, if not impossible, to develop detailed guidelines 

without dealing with the elements that make a building occupancy specific. This is where a 

connection to building use / occupancy / type can be helpful. Where used in building regulations, 

"building occupancy" is associated with characteristics of occupants that are going to use it on a 

regular basis: patrons in places of assembly, students in schools, elderly people in nursing homes, 

detainees in prisons, travelers in airports and subway stations, etc. In considering how this concept 

can be applied more specifically to the PBD process, the relationship can be viewed through the prism 

of the "building occupancy spectrum" (Fig. 2). 

Figure 2. Data treatment schema of various sources, through the building occupancy spectrum, in 

order to get qualitative and quantitative parameters used in PDB approach 

In order to develop detailed occupancy-specific guidelines, several steps are needed: 

- First, the proposed framework is used to examine different sources in order to collect pertinent 

data for each building occupancy, and to try to solve issues related to the perception of risk, the 

level of risk acceptance the AHJ is prepared to accept (or has accepted in the past), and the nature 

of the causes that led to fire injuries and life loss (so to extract quantified performance criteria). 

- Next, scenario characteristics will be elaborated considering the parameters of the fire 

development itself (fire design scenarios) and considering the human behavior parameters needed 

to perform egress calculations (behavioral scenarios). 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

- Finally, examination of different fire protection strategies would be conducted, including data 

from fire events where these strategies were either efficient or inadequate to ensure the fire safety 

function. As staff, rescuers and fire fighters are also components of the fire protection system, 

data will also be collected for each building occupancy type, since the nature, actions and number 

of this people vary with occupancy types. 

At present, the development of the framework is based primarily on data available in the USA, with 

input to the proposed framework mainly composed of data gathered from: 

- Fire statistics collected by the National Fire Protection Association (NFPA) and the US Fire 

Administration (USFA) - in their databases as well as fire investigation reports. This is seen as 

primary main sources for fire data. Indeed, information from fire statistics and fire investigations 

reports is important to collect and analyze as these past events are the most realistic ones. These 

sources are particularly valuable for estimating human behavior parameters as people were 

actually put into situation. Similar investigation reports may include coroner reports as they can 

appear very useful to determine the toxic doses absorbed by the fire victims and the circumstances 

(7) of fire fatalities ; 

- Building and fire codes and standards (International Code Council (ICC), NFPA, local). These are 

important to consider not only because they are the documents where prescriptive requirements 

are presented so they represent the point of comparison with Performance-based Design 

alternatives, but also because some valuable information can be extracted when examining the 

factors that contributed to regulation changes; 

- Agency- or occupancy-specific guidance (e.g., General Services Administration (GSA), 

Department of Veterans Affairs (DVA), Joint Commission on Accreditation of Healthcare 

Organizations (JCAHO), etc). These are important to obtain occupancy-specific requirements that 

may go over and above minimum building and fire regulation, including operational guidelines 

for staff, employees and other who have an impact on fire safety; 

- AHJ-approved Performance-based Design reports. These are important because they reflect 

approved parameters for acceptance criteria, scenarios and fire protection strategies. It should be 

noted that these collected parameters only give an indication of accepted values as it is intended 

that they are highly dependent on the decision making process that allowed the engineer and the 

AHJ (and the other relevant stakeholders) to approve these parameters on a particular project. 

CHARACTERIZING THE BUILDING OCCUPANCY SPECTRUM 

Although life safety is a key objective of the proposed PBD framework, the building 

occupancy spectrum has to be constructed from a much broader perspective than fire safety alone. 

This is because buildings are the creation of architects – designed for clients and occupants primarily 

for "normal" use. This is where many of the other guides fall short – they assume the emergency 

condition to be a primary driver in building and occupant response, when in fact this in not the case. 

As reflected in Figure 1, the integration of fire safety features, although vital to the building global 

safety, is not a primary, or at least not the sole concern of the building users/designers/owners. This is 

where building occupancy classification can help. However, classification of buildings by several 

agencies dealing with fire safety (i.e. ICC and NFPA for regulatory purposes or NFPA and FEMA for 

fire statistics) is not homogeneous. 

A primary classification of the building uses is given in Figure 2, but this classification may not be 

detailed enough to capture all the specificities of all the possible uses of a building. For health care 

facilities, for example, ICC(8) gathers the following buildings in its institutional group I2: child care 

facilities, detoxification facilities, hospitals and mental hospitals and nursing homes. The problem 

with all the different subdivisions in the building occupancies is that the sampling decreases in size as 

one selects one particular type of building. Table 1 provides the different sub-categories of US 

hospitals inventoried by the American Hospital Association (AHA) for 2008. 
 

 

 

 

 

 

 

 

 

 

 

Number of U.S. Community Hospitals 5,010 

Number of Federal Government Hospitals 213 

Number of Nonfederal Psychiatric Hospitals 447 

Number of Nonfederal Long Term Care Hospitals 129 

Number of Hospital Units of Institutions (Prison Hospitals, College Infirmaries, etc.) 16 

Total Number of All U.S. Registered* Hospitals 5,815 

*An institution may be registered by the American Hospital Association as a hospital if it is accredited as a hospital by the Joint 

Commission on Accreditation of Healthcare Organizations (JCAHO) or is certified as a provider of acute services under Title 18 of the 

Social Security Act and has provided the Association with documents verifying the accreditation or certification. 

Table 1. Classification of US registered hospitals by AHA(9) in 2008 

As presented in Figure 3, health care facilities ("inpatient" facilities) represent a "small" number in 

comparison with office buildings that were estimated(10) to 824,000 in the USA in 2003. Figure 4 

shows that the current stock of offices still contains a significant portion of buildings that were 

constructed prior to 1970 (an estimated 346,000 – about 42% of the existing office buildings in 2003). 

Figure 3. Commercial building distribution according to their occupancy type in the USA in 2003(10) 

Figure 4. Construction year distribution of three building occupancy uses(10) 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ASSESSING ACCEPTANCE CRITERIA FOR FIRE SAFETY OBJECTIVES 

With respect to acceptance criteria related to the life safety objective(s) for different building 

groups, the aforementioned PBD guidance documents agree that data should be collected in regard to 

the targeted population (adult workers in offices are more "resistant" to the effects of a fire than 

children in schools, elderly people in retirement homes or patients in hospitals). Ideally, this means 

that the quantified criteria should take the different types and levels of vulnerability into 

consideration. However, specifics regarding the targeted populations and possible systematic methods 

to assess them are not provided. In addition, if the guides also consider the estimation of individual 

risk or societal risk, they do not provide a detailed method regarding the estimation of these risks for 

different building occupancies. At least, they should have made reference to studies(11) correlating the 

levels of "acceptable" risk with the population vulnerability and the level of risk control which are 

both functions of the building occupancies: societies and individuals are more concerned about the 

possible loss of multiple "vulnerable" persons who do not control their own risk than about the loss of 

the same amount of persons who seem to willingly take some risks (patients in hospitals and children 

in schools are highly dependent on other people to evacuate during emergency situations, whereas 

workers in industrial plants accept to be at the vicinity of hazardous materials, in exchange of a 

monetary compensation). 

The use and occupancy classification for specific buildings or facilities, as described by ICC(4) already 

takes into consideration the fact that some buildings can represent a "substantial hazard to human life 

in the event of failure" (jails and detention facilities are then classified in Performance Group III) or 

they can be "designated as essential" (hospitals are then classified in Performance Group IV). In a 

sense, this classification shows that buildings classified in higher performance groups, the magnitude 

of the design hazardous event or "perturbation" has to be moderate, if not mild. 

This notion of "perturbation" - in the context of other stakeholders' objectives, such as business 

interruption - has been examined in some detail, with key observations summarized in the following 

paragraphs. 

Specific building types have specific "chronic" demands 

The concept of "competing objectives" is not new, and it has been noted that competing objectives 

should be addressed in PBD(12). However, there has been little or no discussion with respect to how 

one prioritizes competing objectives. In a move toward understanding how users might prioritize 

objectives, the terms ‘chronic’ and ‘acute’ are introduced. As used here, the association between the 

building and its occupants during normal use is described through "chronic" objectives – those 

objectives which are based on the regular use of the building. In this taxonomy, hazard events (fire, 

flood, earthquake...) may be seen as "perturbations" of the "building-occupant" system. Objectives 

(or situations) associated with such events are then defined as "acute". Buildings are complex 

structures by essence; in addition to the building parts devoted to its chronic functions (e.g., 

auditorium in theater, classroom in school), buildings contain systems intended to support the chronic 

operation of the building (electricity, plumbing, heating, ventilating and air conditioning, etc). These 

support systems are used in an everyday basis, where as the fire protection systems (as part of all 

emergency systems) are meant to be used in the specific event of a fire (and unwanted false alarms). 

Because of this objective dichotomy, competing priorities may appear between the "chronic" 

objectives and the "acute" ones related to fire safety. This is important when trying to understand how 

people might respond in acute situations as compared with chronic conditions. 

Tubbs and Meacham(13) summarize some of these competing priorities related to hospitals: 

- patients’ comfort is offered by large, well-lit facilities that challenge the fire safety concept of 

compartmentation, 

- design flexibility due to ever-changing programmatic needs may appear as a cost-benefit 

challenge for the fire safety design, 

- security needs challenge safe egress capabilities. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Other examples related to the above include: 

- open spaces in ‘spec’ office buildings, which are outfitted at the request of the entity renting the 

space, may conflict with compartmentation desires; 

- during the lifespan of a building, contents and occupants may vary in characteristics and number, 

especially in the numerous buildings of multi-occupancy type; 

- following the events of September 11, 2001, an increase of security points inside public places 

creates situations that challenge the chronic objective of providing uncongested pedestrian access 

and movement and the acute fire safety objective of easy egress (e.g., many spaces where airport 

security screening has been set up where probably not designed for large numbers of densely 

packed people queuing up and the exit system may not be designed to readily accommodate this). 

Looking at hospitals in particular, other "chronic" objectives exist due to their very specific design: 

patients in Intensive Care Units (ICU) are often connected to machines that keep them alive, operating 

rooms are designed to be sterile and outfitted with life-sustaining equipment that cannot be quickly 

removed, etc. In addition to the criteria associated with the fire threat, performance criteria related to 

the safeguarding of the life supporting pieces of equipment should be established, not only as a result 

of the fire threatening conditions but also as a result of a potential application of a fire suppression 

system. For hospital wards, the main nurse station could be positioned in an open corridor so nurses 

have a constant view of the ICU (hospital stakeholder’s objective), which is in not in accordance with 

the fire safety objective of limiting the smoke and fire spread by adding compartmentation features. 

"Chronic" objectives may also appear in clear contradiction with the safety objective of evacuation in 

case of a fire in buildings such as correctional facilities where people have to be kept behind locked 

doors. Less obvious types of buildings such as casinos are primarily designed to have the patrons 

focused on staying at the same spot for long periods of time. 

With respect to chronic objectives, perturbations, and acute objectives, a crucial concept to analyze 

and quantify is the duration of the shift between the "chronic" (normal) condition to the "acute" (fire 

emergency) condition – this can have a significant impact on establishment of required safe egress 

time (RSET). Another critical concept to analyze and quantify is the period required to restore the 

facility to "chronic" (normal) operations. 

It is also important to note that in particular areas, safety objectives can also compete, especially when 

hazardous materials are involved. For example, in plants manufacturing nuclear fuel, PMMA based 

"glove boxes" that are specially treated with lead to absorb the effects of radioactive materials that 

operators manipulate are a very important source of combustible. Nevertheless, they may appear to be 

more effective for this safety purpose than the glass based "glove boxes" because the "chronic" 

objective supersedes the "acute" objective. Fire can also disrupt a safety procedure of a hazardous 

system; in that case, restoration of that safety procedure may also supersede fire safety protocols. In 

order to deal with this potential competition of objectives, a feedback loop between the different 

stakeholders should always been applied. 

Chronic objectives and fire safety objectives also have to adapt in time. In day-care occupancies and 

health care occupancies, one of the biggest challenges is reducing the chances that a patient may 

acquire a health care-associated (nosocomial) infection. Related to this objective, the introduction of 

alcohol-based hand rubs was considered as a potential source of fire, especially when positioned 

above an electrical source. In consequence, NFPA had to study this fire hazard issue, introduced 

specific paragraphs in the 2006 version of the Life Safety Code and revised them in its 2009 version(3) 

(paragraphs 18.3.2.6 and 19.3.2.6 for health care facilities). 

To address the above issues, the proposed integrated approach requires describing the building’s

"chronic" uses and related demands, which comes before the integration of the stakeholders' 

objectives with respect to acute objectives associated with system perturbations. It also requires 

consideration of the transition between the chronic (normal) use of the building and the fire 

emergency period, which is a key issue in the evacuation. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Risk tolerance criteria and building uses 

Some building occupancy uses are more regulated than others because the associated societal risk 

tolerance varies according not only to the likelihood and the consequence of fire events, but also to 

the number of simultaneous casualties, vulnerable populations and the level of safety control that the 

public concedes to third parties. A characteristic example of low fire risk tolerance applies to health 

care facilities, where vulnerable populations are present and where the public literally puts their lives 

into the hands of the healthcare facility staff. 

As an aftermath of the Wincrest Nursing Home fire (arson) that caused 24 deaths on January 30, 

1976, the City of Chicago and its Board of Health made several safety improvements including(14): 

- installing a sprinkler system in all new and existing nursing homes and that the new sprinkler 

systems must be connected with the fire alarm system, 

- requiring emergency training for all nursing home staff which includes transporting patients 

during an emergency, 

- abolishing dead end corridors in nursing home, 

- organizing disaster plan and regular emergency drills made by the Board of Health, 

- enforcing smoking rules so residents / visitors must smoke in designated areas supervised by staff. 

In 2003, two fires occurred in two different unsprinklered nursing homes in the US: one fire in 

Hartford, Connecticut, causing 16 casualties and one fire in Nashville, Tennessee, causing 15 deaths. 

As a consequence, Centers for Medicare and Medicaid Services (CMS) of the US Department of 

Health and Human Services issued on August 13, 2008 a final rule regarding fire safety requirements 

for Long Term Care facilities and more particularly, the installation and the maintenance of automatic 

sprinkler systems in the whole building: "This final rule requires all Long Term Care facilities to be 

equipped with sprinkler systems by August 13, 2013. Additionally, this final rule requires affected 

facilities to maintain their automatic sprinkler systems once they are installed(15)". 

Several lessons can be drawn from these two sets of events: 

- because of the US regulatory system, cities, states and the whole nation can decide of their own 

requirements regarding fire safety. A tragic event occurring in one state (Illinois in 1976) was not 

enough to "trigger" the same level of requirements in other states; 

- nevertheless, health care management has entered under a federal scope as the federal financial 

participation rate ranges from 50 to 83 percent of each dollar spent by a state which is then 

required to describe the nature and scope of its program in comprehensive written plans submitted 

to CMS(16). If the regulation is enforced at a federal level, more facilities will be affected by the 

regulation and the corresponding sampling in fire statistics may get larger (even if the sprinkler 

requirement is adopted nationwide, states still have the possibility to increase the level of safety 

by requiring additional fire safety measures); 

- the population is getting older so the public is going to be more and more concerned about 

multiple deaths fires occurring in nursing homes and other health care facilities (it should be 

noted that an average of about 2,300 of the nation’s approximately 16,300 US nursing homes

reported a structural fire each year from 1994 through 1999 and that annually, the average number 

of fire related nursing home deaths nationwide was about five(17)). 

These two examples are relevant of the very low risk tolerance of the AHJ (local and federal) is 

prepared to accept in case of fires in nursing homes. As a consequence, the minimum requirements 

are associated with the installation and the maintenance of a sprinkler system, which efficiency to 

prevent the extension of a fire is quite high. For this particular case, it seems that any PBD approach 

would have to consider a sprinkler system in this type of facilities as a fire safety measure, as an 

imperative demand from the AHJ. 

Going forward, the situation for nursing homes and requirements for sprinklers will serve as a basis 

for assessing other occupancies, as it is expected that similarities may exist for other highly regulated 

building uses, and capturing such experience is important to benchmarking "tolerable" safety. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SELECTING AND EVALUATING DESIGN FIRE SCENARIOS 

Considering the elaboration and the selection of design fire scenarios upon which the PBD 

solutions are to be based, Chapter 8.3 of the SFPE Engineering Guide to Performance-Based Fire 

Protection Design(1) (SFPE Guide) presents various techniques that can be used in identifying 

possible fire scenarios, such as Failure Modes and Effects Analysis (FMEA), failure analysis, "what 

if?" analysis. It also states that "the scarcity of the [historical] data needed to assigning probabilities 

[to fires] can limit this approach for conducting Performance-based Design for a specific [new] 

project". Concerning past fire histories, it is indicated that they "can provide some very useful input 

by identifying potential failures of various items, as well as frequencies and severities of fires". It 

should be noted that the SFPE Guide presents various tools useful to describe the scenarios as 

possible chains of events; quantified data is still to be gathered in order to quantify the probabilities of 

these events. Unfortunately, like the SFPE Guide, most guides provide fewer sources about how to 

quantify the possible events than tools used to identify possible scenarios. Nevertheless, the guides 

suggest that data should be collected using fire incident databases as they provide some information 

regarding how fire started, spread and ultimately led to fatalities and injuries (or building damage for 

a property loss objective). Studies on the reliability of fire protection systems including smoke 

detectors and automatic suppression systems are also sparingly available, as often only single values 

are given in quantitative risk assessment studies. Here again, guidance documents on Performancebased Design are very generic, as they were not designed to provide detailed methods of conducting a 

PBD approach for a particular building project. They also propose different methods to achieve the 

fire safety goals of the PBD approach, using risk matrix or a quantified fire risk assessment, and they 

emphasize different aspects on the selection of design fire scenarios. Nevertheless, they all agree to 

obtain data for fire statistics and fire investigations reports of "historical fires". 

As pointed out previously, it seems important to intensively examine fire incident databases and fire 

investigation reports in order to extract the most accurate parameters of "real" fires and therefore to 

constitute a validated, if not exhaustive, base for the parameters needed to imagine and ultimately 

select the design fire scenarios (with eventually their estimated incidence on the overall fire risk). 

Table 2 below is an example of data presented in the NFPA reports of US fires in selected 

occupancies(18). This data shows a correlation between the extent of flame damage and the number of 

casualties and injuries as well as the direct property damage. A discrepancy appears between the fires 

that are related to the life safety objective as their maximum extent is the room of fire origin and the 

fires that are related to the property damage objective as the more the fire extents, the more damage it 

causes, which could indicate that the design fire scenarios for the life safety objective may not be the 

same for other business or property oriented objectives. This table, as well as the global results that 

are usually presented in the NFPA reports, is too general to be used in a Quantitative Risk Analysis. 

For example, 510 fires confined to room of fire origin led to 44 civilian injuries. What is the number 

of fires that led to multiple (5, 10, even 44) injuries? Did these fires occur in the same type of health 

care facilities, in the same state, with the same fire ignition conditions? 

Extent of Flame Damage Fires Civilian 

Deaths 

Civilian 

Injuries 

Direct Property 

Damage (in 

Millions) 

Confined or contained fire 560 18% 0 0% 8 9% $0.1 0% 

Confined to object of origin 1,930 61% 0 0% 29 33% $3.8 18% 

Confined to room of origin 510 16% 1 100% 44 51% $4.2 20% 

Confined to floor of origin 60 2% 0 0% 1 1% $2.1 10% 

Confined to building of origin 90 3% 0 0% 5 6% $10.3 49% 

Extended beyond building of origin 10 0% 0 0% 0 0% $0.7 3% 

Total 3,150 100% 1 100% 87 100% $21.3 100% 

Table 2. Structure Fires in Health Care Facilities(18), Excluding Nursing Homes by Extent of Flame 

Damage (1999-2002 Annual Averages)
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NFPA reports, as well as USFA reports, are a good starting point in order to collect generic 

information about fires in selected occupancies. Nevertheless, results shown in these reports do not 

seem to be directly usable for populating event trees, as important parameters of the event trees were 

blended in making the data too generic. A possible way to overcome this situation is to analyze 

directly the data in the NFPA or USFA databases, by segmenting once again the problem and 

considering each type of health care facilities considered in Table 2. Investigation reports also are an 

alternative to the generic data found in the aforementioned NFPA reports. Some of them have been 

published as a consequence of multiple death fires. 

The extensive work by Bryan(19), DiNenno and Milke on 65 fires in heath care facilities between 1977 

and 1980, is to be analyzed thoroughly as it contains a lot of information about behavioral response 

patterns of staff and patients, as well as the efficiency of the different technical fire safety measures in 

these facilities. 

According to Tillander(20) , the best source of information regarding the necessary input for fire 

quantitative risk assessments is fire statistics, even she also stated that "the statistical approach can be 

used only existing buildings on which the data is not too sparse. When suitable statistics are available, 

the point estimates or the probability distributions can be derived". Nevertheless, Tillander as well as 

Salisbury(21) et al. indicate that the predictive use of statistical data should be made with care, as the 

conditions which have made up the data may be different in the future. This remark is also valid when 

looking at statistics from the past, prior to a major change in fire safety requirements implementation 

or in building contents, such the one that occurred with the advent of plastic materials. Considering 

the case of nursing homes, fire trends over the years would have to be assessed in conjunction with 

the decrease of the number of nursing homes (sampling), changes in the fire safety tasks of the staff, 

as well as the ratio staff / patient, the patient pathologies and age distributions. 

Another advantage of fire investigations is connected with the improvement of fire modeling when 

this technique is used, for forensic purposes, to analyze the development of a fire event. Data for fire 

models are sometimes estimated from specific experiments conducted with actual materials collected 

on the fire scene(22), which is a way to narrow the uncertainties associated with the variability of the 

parameters of fire modeling and human behavior for the incident being investigated. 

PROPOSING AND EVALUATING FIRE SAFETY STRATEGIES 

Building codes or fire safety standards are organized in the USA or around the world, in 

relation to the type of facilities or particular types of hazards that could be located in facilities. 

Comparisons between a prescriptive fire safety solution and an engineering solution are then based on 

the type of building occupancy. 

Data from fire incident statistics and investigation reports can also be used in order to determine if the 

building where a fire occurred was defined according to the prescriptive regulations. This kind of data 

should be exploited in order to set up the level of safety of the prescriptive regulation at the time the 

building was constructed or renovated. By examining fire statistics for several years, it should be 

possible to quantify the benefits or eventually the drawbacks of the last implemented fire safety 

requirements. For heath care facilities, regulated by the Joint Commission on Accreditation of 

Healthcare Organizations (JCAHO) and for all these facilities which established smoke-free 

environment / no smoking policies, it was observed that visitors were giving smoking materials to 

patients and residents without the health care staff’s knowledge(23). This phenomenon was found as to 

explain why this type of ignition source was not decreasing in the corresponding fire statistics. 

At last, a feedback loop, as designed in models used in system dynamics to investigate the knock-on 

effects of changes on a system, should always been applied to verify that the implementation of a fire 

safety management measure does not end up with creating an unsafe counterproductive measure. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fire drills in health care facilities 

Because of the lack of mobility of vulnerable patients, importance is given to the health care staff as 

components of fire detection, fire alarm, evacuation / defense in place strategy and even fire 

extinguishment. Fire drills appear to be an adequate means to quantify the level of skill maintenance 

by the staff in this matter. The American Health Care Association(24) (AHCA) presents the following 

review of the Life Safety Code by the Center for Medicare & Medicaid Services (CMS). 

"Life safety surveyors have recently been citing facilities in which all staff members did not 

participate in at least 4 quarterly fire drills per year. Although this may sound like a simple and 

reasonable requirement, not all staff members are present when their shift has a drill. Staff members 

may be on vacation, sick, in training outside the facility, etc. Nowhere in the Life Safety Code does it 

require that all staff members must participate in a minimum of 4 fire drills per year". 

The NFPA requirements in the Life Safety Code(3), concerning staff training and fire drills, in heath 

care facilities are mentioned in: 

- paragraph 18.7.1.2: all employees shall be periodically instructed and kept informed with respect 

to their duties under the required [plan for the protection of all persons in the event of fire]; 

- paragraph 18.7.1.6: drills shall be conducted quarterly on each shift to familiarize facility 

personnel (nurses, interns, maintenance engineers, and administrative staff) with the signals and 

emergency action required under varied conditions; 

- paragraph 18.7.1.8: employees of health care occupancies shall be instructed in life safety 

procedures and devices. 

The Life Safety Code does require that a minimum of 4 fire drills per shift per year for a total of 

12 fire drills be held by a facility. Sections A18 & 19.7.1.2 states that "the purpose of a fire drill is to 

test and evaluate the efficiency, knowledge, and response of institutional personnel in implementing 

the facility fire emergency plan". The purpose of the drill is to test the capabilities of the staff present 

during the drill. Nevertheless, it is very likely that during actual fires in facilities, all staff on the shift 

will not be present. An excellent opportunity to test this situation is to conduct a drill when all staff is 

not present. 

For its part, NFPA(25) is aware that the purpose of fire drills is "not to disturb or excite patients" as 

paragraph 18.7.1.5 (and 19.7.1.5) states that "infirm and bedridden patients shall not be required to be 

moved during drills to safe areas or to the exterior of the building". NFPA also indicates that "many 

health care facilities conduct fire drills without disturbing patients by choosing the location of the 

simulated emergency in advance and by closing the doors to patients' rooms or wards in the vicinity 

prior to initiation of the drill". 

It should be noted that inspections and surveys are also a good means to collect data, not only about 

installed and maintained technical fire safety measures but also for estimating the actual level of 

implication of staff and other operators in fire or other emergency situations. 

CONCLUSIONS 

Existing Performance-based guidance documents describe possible ways to create alternate 

solutions to prescribed requirements. However, even though they emphasize the importance of 

parameters such as the definition of the acceptance criteria or the selection of the design scenarios, 

they are too general in defining and quantifying these parameters for a particular project. In order to 

help identify and evaluate the relative importance of the most influential parameters of a PBD 

approach for a project, an integrated approach to PBD for life safety across different building use 

groups is proposed. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In creating the integrated PBD approach, a first task consisted of breaking down the analysis and 

design problem into manageable pieces categorized by building occupancy uses, defined in part by 

their own everyday or "chronic" objectives. The analysis of "chronic" objectives for occupancies such 

as healthcare facilities, casinos, airports, and offices has already illustrated a competition between 

their respective chronic objectives and the "acute" ones defined in emergency situations such as fires, 

which are perceived as a perturbation of the "building–occupant" system. Because of this competition, 

a tremendous effect exists of having building occupants "shift" from their usual activities to the 

emergency evacuation process, which is very important since this effect has to be quantified in egress 

calculations as it determines the "pre-movement" time of the RSET. It has also be found that, for 

objectives related to business interruption of buildings defined as "essential to the community", the 

period following the "perturbation" is also important. Thus, the examination of the "chronic" 

objectives, for every building occupancy uses, appears to be a necessary task to perform prior to any 

fire safety analysis. Techniques, derived from the field of system dynamics, appeared to be useful in 

order to analyze the effects of implementing the categorized "building–occupant" systems with fire 

safety measures and their use will tend to be generalized within the proposed PBD approach. 

The benefit of looking more closely at regulatory, operational and loss history though the study of US 

certified nursing homes showed that the low fire risk tolerance of this specific building occupancy use 

had a tremendous impact on the minimal level of fire safety demanded by the Authority Having 

Jurisdiction, as the installation and maintenance of sprinklers are required for new and existing 

nursing homes. This situation and resulting requirements for sprinklers will serve as a basis for 

assessing other occupancies, as something similar could also appear for other highly regulated 

building uses. 

When analyzed through the spectrum of the building occupancy uses, data sources, including but not 

limited to fire statistics and fire investigation reports, tend to provide more pertinent and applicable 

data for similar projects, therefore reducing uncertainties related to the use of generic data. 

Inspections and surveys related to very precise situations will also be included in order to gather 

specific data on fire management procedures, as it was shown that staff constitutes a showpiece of the 

fire safety strategy in nursing homes. 

REFERENCES 

1

Society of Fire Protection Engineers, SFPE Engineering Guide to Performance-Based Fire 

Protection, Second Edition, SFPE, Bethesda, MD (USA) 2007 

2

Society of Fire Protection Engineers, SFPE Code Official's Guide to Performance-Based 

Design Review, SFPE, Bethesda, MD (USA) 2004 

3

National Fire Protection Association, NFPA 101 "Life Safety Code®", NFPA, Quincy, MA 

(USA) 2009 

4

International Code Council, ICC Performance Code for building and facilities, International 

Code Council, INC., Whittier, CA (USA), 2009 edition 

5

International Fire Engineering Guidelines (IFEG), Australian Government, State and 

Territories of Australia, 2005 

6

Meacham, B.J., "International Experience in the Development and Use of PerformanceBased Fire Safety Design Methods: Evolution, Current Situation, and Thoughts for the Future," 

Invited Paper, Proceedings of the International Association for Fire Safety Science, 6th International 

Symposium, Poitiers, France, July 1999, pp.59-76 

7

Ian Thomas, Dorothy Bruck and Michelle Barnett, "Is Consideration Of Evacuation Relevant 

to Most Fire Fatalities? Using the CESARE Coronial Database to Investigate the Utility of 

ASET/RSET Calculations", Proceeding of the 4th International Symposium on Human Behaviour in 

Fire, pp.411-420, Interscience Communications, London (UK), 2009 

8

International Code Council, International Building Code, section 308, (USA) 2009 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9

American Hospital Association, Fast Facts on US Hospitals, 

http://www.aha.org/aha/resource-center/Statistics-and-Studies/fast-facts.html 

10US Energy Information Administration (EIA) - 2003 Commercial Buildings Energy 

Consumption Survey (CBECS) Detailed Tables – most recent available, released: September 2008 

(http://www.eia.doe.gov/emeu/cbecs/cbecs2003/detailed_tables_2003/detailed_tables_2003.html#enduse03) 

11Wolski, A., Dembsey, N. and Meacham, B., "Accommodating Perceptions of Risk in 

Performance-Based Building Fire Safety Code Development," Fire Safety Journal, Elsevier, London, 

Vol. 34, No. 3., pp.297-310 

12Meacham, B.J., Editor, and Johann, M., Associate Editor, Extreme Event Mitigation in 

Buildings: Analysis and Design, National Fire Protection Association, Quincy, MA, April 2006 

13Jeffrey S. Tubbs and Brian J. Meacham, "Design solutions", chapter 9 of Egress Design 

Solutions – A Guide to Evacuation and Crowd Management Planning, John Wiley and sons, 2007 

14Emergency Management Higher Education Program Report – Federal Emergency 

Management Agency (FEMA) (training.fema.gov/EMIWeb/edu/ARRPT/January%2030,%202009.doc) 

15Department of Health and Human Services – Centers for Medicare & Medicaid Services –

42 CFR Part 483 – [CMS-3191-F] RIN 0938-AN79 "Medicare and Medicaid Programs; Fire Safety 

Requirements for Long Term Care Facilities, Automatic Sprinkler Systems", Federal Register, vol. 

73, No. 157, Wednesday, August 13, 2008, pages 47075-47092, 2008 

16United States General Accounting Office, "Medicaid Financial Management - Better 

Oversight of State Claims for Federal Reimbursement Needed" – GAO-02-300, February 2002 

(http://www.gao.gov/new.items/d02300.pdf) 

17United States Government Accountability Office, "Nursing Home Fire Safety – recent fires 

highlight weaknesses in federal standards and oversight" –– GAO-04-660, July 2004 

(http://www.gao.gov/new.items/d04660.pdf) 

18Marty Ahrens (NFPA), Selections from the U.S. Fires in Selected Occupancies – Health 

Care Facilities, excluding Nursing Homes, NFPA, Quincy, MA (USA), March 2006 

19J.L. Bryan, P.J. DiNenno, and J.A. Milke "The Determination of Behavior Response 

Patterns in Fire Situations, Project People II. Final Report – Incident Reports, August 1977 to June 

1980", NBS-GCR-80-297, Washington DC (USA), December 1980 

20Kati Tillander, "Utilisation of statistics to assess fire risks in buildings", VTT publication 

537, VTT Technical Research Centre of Finland, 2004 

21M Salisbury, P Johnson, E Yii and MC Hui, "QRA and fire safety – a beneficial 

experience...", Interflam 2007, proceedings of the eleventh conference, volume 2, pp. 1253-1263, 

Interscience Communications, London (UK), 2007 

22William Grosshandler, Nelson Bryner, Daniel Madrzykowski, and Kenneth Kuntz, Report 

of the Technical Investigation of The Station Nightclub Fire, report NIST NCSTAR 2: Vol. I and 

Vol. 2, National Institute of Standards and Technology, June 2005 

23Daniel J. O’Connor, "Health care occupancies", chapter 15, section 20 of the 20th edition of 

the Fire Protection Handbook, NFPA, 2008 

24American Health Care Association (AHCA) "Life Safety Update: Staff Participation in Fire 

drills" http://www.ahcancal.org/facility_operations/fire_life_safety/Pages/StaffParticipationinFireDrills.aspx 

25NFPA, Info on health care occupancies, 

http://www.nfpa.org/itemDetail.asp?categoryID=792&itemID=20722&URL=Safety Information/For 

consumers/Occupancies/Nursing homes/Info on health care occupancies 
 

 

 

Appendix A2
 

“Ready-to-Use” Building Layouts and Combustible Packages for 3-D Fire Simulations" 

presented at the Fire and Evacuation Modeling Technical Conference 2011
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

PROCEEDINGS, Fire and Evacuation Modeling Technical Conference 2011 

Baltimore, Maryland, August 15-16, 2011 

“READY-TO-USE” BUILDING LAYOUTS AND COMBUSTIBLE PACKAGES 

(a) FOR 3-D FIRE SIMULATIONS

Alberto ALVAREZ and Brian J. MEACHAM
 

Worcester Polytechnic Institute
 

100 Institute Road, Higgins Laboratories
 

Worcester, MA, 01609, USA
 

e-mail: al_alvarez@wpi.edu
 

ABSTRACT 

In recent years, complex 3-D computational fire 

effects models have been widely used by fire 

protection engineers to simulate the consequences of 

fire and to assess effectiveness of fire mitigation 

options. This has happened in part because these 

tools have become increasingly user friendly. 

However, it may not always be appropriate to use a 

complex model just because it is available. In 

addition, the use of these complex tools requires 

considerable time, both for users to create input data 

files and analyze the results, and for computers to 

produce the simulations. With respect to input files, 

independent of the description of the initial designbasis fire itself, information and data are lacking 

about the way the building itself should be described 

as input data, the degree of detail that is necessary in 

order to capture the elements that affect the 

validation of the simulation, and how to optimize 

mesh size so that critical elements can be properly 

incorporated without resulting in a prohibitively 

lengthy calculation time. In order to begin addressing 

these issues, this project aims to provide guidance on 

how to select the right type of tool to fit the 

engineering application, to collect and make available 

to the entire fire community, representative building 

layouts for common occupancy groups, such as 

schools, offices in high-rise buildings, and hospitals, 

which can form a common basis for estimating, 

assessing and verifying building-related model 

parameters, and to collect and make available a set of 

„combustible packages‟ representing 3-D objects 

such as chairs, couches, and beds, which contain heat 

release rate, chemical reaction, and toxicity 

properties needed for the simulations. Together, the 

tool selection guidance, building configurations and 

combustible packages will help fire protection 

engineers become both more efficient and effective in 

applying the best tools for the application at hand. 

INTRODUCTION 

Within the performance-based fire protection design 

framework, tools are used in order to estimate the 

consequences of fire design scenarios, upon which 

different fire protection trial designs are evaluated. 

A fire scenario describes the evolution with time of 

the fire, from its ignition to its extinguishment. Not 

only fire is a threat to the building occupants, but also 

to the building itself, to its contents and to its own 

structure. Life safety is a common objective for any 

built environment and concerning fire hazard, it is 

essential to evaluate the consequences of the fire in 

terms of heat effects (temperature and thermal dose) 

as well as in terms of toxicity and visibility loss 

which can prevent occupants from finding their way 

to a safe place so they subsequently succumb to 

untenable heat and toxic conditions. In order to 

conduct this analysis, a fire design scenario shall 

contain information necessary to evaluate the heat 

released during the fire and also fire effluent 

productions. This information is then added to the 

information related to the description of the built 

environment and incorporated, as user input, to fire 

effects tools. When selecting appropriate tools for 

analysis, several factors need to be considered. 

Different levels of complexity 

The Society of Fire Protection Engineers (SFPE, 

2011) defines the three following types of fire effects 

tools, based upon their levels of complexity: 

- algebraic models, which include empirical or 

analytical equations to describe localized 

phenomena such as the plume region 

(temperature and velocity), the ceiling jet, and 

smoke filling in an enclosed space; 

- zone or lumped parameter models, which divide 

spaces into control volumes where the quantities 

are spatially homogeneous (and which often 

include add-on sub-models dealing with 

particular aspects of the fire description); 

- Computational Fluid Dynamics (CFD) models, 

which can calculate flows through complex 

geometries by dividing the considered space in 

relatively small elements where a set of 

governing equations is numerically solved. 

Hybrid tools combining a zone model with a CFD 

model, a fire effects models with a HVAC network 

model may also be considered when assessing fire 

consequences. 

(a) COPYRIGHT 2011, A. ALVAREZ and B.J. MEACHAM, All rights reserved 

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Understanding and recognizing the differences in 

level of complexity and outcomes delivered is the 

first step in matching tools to applications. 

Different uses have different constraints 

The next step in selecting a tool is to understand 

issues associated with objectives and constraints on 

the project, such as time, resources, and level of 

analysis required. At the start of a complex project in 

the consulting environment, for example, fire 

protection engineers (FPEs) are often asked to 

provide ideas of the possible fire protection 

measures, even when the project itself is not well 

defined. At this stage, the level of analysis required 

will be driven by the level of complexity needed 

given the scarcity of input data describing the project 

(i.e., building layout and combustible contents which 

provide potential fire sources) and the potential 

impact of the analysis on the project direction. As a 

project passes through the steps of feasibility, 

concept design and schematic design, FPEs are able 

to refine their initial ideas using more complex tools 

as appropriate. 

Ultimately, many projects which require 

performance-based analysis involve complex 

building geometries, which present challenges for the 

use of algebraic and zone models. As such, given the 

availability of CFD fire effects tools, and the fact that 

they can handle more complex geometries, they can 

appear to be the „best‟ candidates for assessing the 

fire protection design of such projects. However, due 

to computational constraints (in terms of processors 

which manage the computational time and in terms of 

usable memory which sets up the limits of the refined 

computational grid), it may not practical or costeffective to perform one, let alone a series of detailed 

CFD simulations. In such cases, a decision often 

needs to be made regarding the trade-off between 

complexity and time. In the end, it may be that the 

FPE has to rely on less complex fire effects tools 

from a time perspective, while demonstrating that the 

less complex tools are validated for handling the 

complex geometry (i.e., the FPE needs to 

demonstrate how the uncertainties related to adapting 

the complex geometry for less sophisticated tools is 

not significantly or inappropriately changing the 

outcome of the engineering solution). 

While time constraints may be an issue for practicing 

engineers, and time and complexity trade-offs may be 

required, this is not the case in other environments, 

such as academia, research and high risk or hazard 

industries. In the academic or research environments, 

for example, it is not uncommon for multi-year 

studies to be conducted. Such studies may involve 

developing new tools, expanding existing tool 

capabilities, and assessing better ways to apply 

existing tools to solve complex engineering 

problems. 

An example of a long-term study dealing with better 

ways to use tools to solve an engineering problem 

can be illustrated by Francesco Colella's PhD thesis 

titled "Multiscale Modeling of Tunnel Ventilation 

Flow and Fires" (Colella, 2010), conducted at the 

Politecnico di Torino. His research objective is 

related to the design of smoke extraction in tunnels of 

several kilometers in length. In this case, a dichotomy 

exists between the needed accuracy to simulate the 

flows around the smoke extractors and the fire, which 

requires describing the local environment with cells 

of a few centimeters, and the smoke flow along the 

whole tunnel, which requires millions of cells and a 

manageable computational time to perform a series of 

scenarios to test the smoke control system. In the 

referenced work, this dichotomy led to the 

formulation of a method allowing the coupling of a 

CFD fire effects tool with a 1-D ventilation network 

tool. The outcome is a hybrid tool where information 

is transferred between the tools and a formula 

describing the minimum extent of the CFD 

computational domain where results are similar to the 

ones estimated with the full CFD representation of 

the tunnel. 

For an example of a very particular and highly 

regulated sector which is high-risk / high hazard, one 

can consider efforts within the nuclear power 

industry, where multi-year projects involving nuclear 

power plant operators, researchers, governmental 

agencies and regulators, have been undertaken 

(Barrachin et al., 2000; Siu et al., 2008). In this 

environment, not only have there been sustained 

research projects aimed at tool development and 

assessment (e.g., NIST/NRC efforts), but also 

development of a process for applying different level 

of complexity tools at different stages in the 

assessment and design process within a general 

quantitative (or probabilistic) risk assessment (QRA 

or PRA) framework. For example, within a QRA 

process, different types of fire effects tools can be 

selected as follows: 

- In the first instance, simple tools which can be 

quickly applied are utilized in order to screen out 

fire scenarios which would have no impact on 

the QRA. This first level of analysis primarily 

consists of applying algebraic models that can be 

edited in a spreadsheet for handing thousand of 

calculations. Since this application is aimed at 

the elimination of the fire scenarios which are 

not relevant for the QRA, it only requires coarse 

description of the domain and conservative 

assumptions of the fire development. 

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- A second more detailed level of analysis can 

then be conducted by applying more complex 

fire effects tools to the remaining scenarios. The 

specific application here is to determine 

quantities that would actually be input for the 

QRA related to fire risk. The events to be 

considered may be framed in time periods of 

several minutes (e.g., time to the first correcting 

action) to several hours (in cases where the fire 

has been spreading and more and more 

correcting actions have to be taken in order to 

maintain core safety). Because thousands of 

simulations may be required to understand the 

risk, and if the compartments can be 

characterized with simple geometries (e.g., "shoe 

box" shaped rooms), application of a zone model 

appears to be the optimum solution in order to 

get the corresponding fire QRA input data. 

- Once specific areas of concern are identified, 

CFD tools can then be used to handle specific 

scenarios involving geometries, such as cable 

trays supporting the transmission of power or 

control information regarding core management 

or safety. In such cases, detailed local 

information is needed to describe the combustion 

and flame spread in cables trays, which 

constitute at the same time extended fire areas 

and targets important for the core safety in the 

global QRA. 

Data availability and fire phenomena 

Two additional critical criteria in the selection of a 

candidate tool for a given application are the 

availability of the input data required to effectively 

apply the tool, and the making sure that the fire 

phenomena that the tool simulates matches the 

assessment needs. 

Assuming for this discussion that the three types of 

fire effect tools are available and have been validated 

to correctly represent the physics for a given 

application, the next criterion regarding 

appropriateness of a tool for an application could 

then be determined by the amount and goodness of 

information that can be collected for the data input 

needed by the different tools. The recently published 

SFPE Guidelines for Substantiating a Fire Model for 

a Given Application (SFPE, 2011) provides a good 

starting point, noting for example the need to 

identify: 

- details of the spatial domain representing the 

built environment, 

- fire design scenario timeframes (from several 

minutes for a single room flashover application 

to several hours for assessing the collapse of a 

structure due to a generalized fire), 

- material properties not only describing the 

combustible contents but also the other building 

elements which "absorb" heat and fire effluents 

as well as the load-bearing elements, 

- initial and boundary conditions, including initial 

temperature in and outside the built environment 

and the ventilation conditions (initial conditions 

including the window and doors status (opened 

or closed) as well the boundary conditions (how 

the doors are leaking or how the mechanical 

ventilation network is set up). 

The final attribute which can be used to assess the 

appropriateness of a tool for a given application is 

related to the application itself; what is being 

assessed, and what features of a tool are required to 

support that assessment. For example, an application 

could be related to assessing fire propagation inside 

the room of fire origin with respect to the safety of 

the occupants in the room. In that case, tools would 

1st be needed to assess the fire spread from the 

burning item to the subsequent ones until the 

flashover is reached. Fire effects tools including 

models assessing flame characteristics, ignition by 

radiation fluxes, etc. would then be considered. Using 

a tool which is too coarse for the application may not 

yield the level of information required to make a 

good assessment. By contrast, the application 

purpose may be to consider the safety of occupants 

remote from the compartment of fire origin, without a 

need to focus on how the fire initially develops. In 

this case, the application is more concerned with 

species production and spread outside of the room of 

origin than with the fire development. In these cases, 

the same tool may be appropriate to solve different 

parts of each problem, but in different ways and at 

different levels of complexity. In the first instance, a 

CFD model may be needed to obtain the degree of 

analysis needed in the room of origin, and a zonemodel may not yield sufficient detail. In the second 

case, however, a zone model may be appropriate for 

simulating initial conditions in the room of origin, 

with a CFD model need to assess smoke and hot gas 

spread outside the room of origin. 

EXAMPLES OF STUDIES TO BE 

CONDUCTED RELATED TO THE USE OF 

FIRE EFFECTS TOOLS FOR GIVEN
 

APPLICATIONS 

It is suggested that the above issues form the basis for 

development of „best practice‟ guidelines for 

selecting fire effects tools based on their 

appropriateness to the application at hand. These 

guidelines would be used in collaboration with 

related guidance, such as the SFPE Guidelines for 

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Substantiating a Fire Model for a Given Application1 

and SFPE Guide to Predicting Room of Origin Fire 

Hazards (SFPE, 2007a) and other such guidance, and 

would support a wide range of industry stakeholders, 

including: 

- FPEs, to select the appropriate tool to solve their 

engineering problems, 

- researchers to develop more tool functionalities 

and to increase tool validation, and 

- the regulators and authorities to have more 

confidence in the engineering solutions when 

these tools are used. 

However, in order to ultimately produce 

comprehensive „best practice‟ guidelines to assess the 

appropriateness of a fire effects tool for a given 

application, it is suggested that a series of both 

generic and specific studies need to be conducted. 

The intent of these studies is to utilize multiple 

participants to develop data and case history to 

illustrate a wide range of issues, such as level of 

detail needed in building configurations for different 

types of problems or occupancies (e.g., life safety in 

hospitals versus apartments), or detail required in 

characterizing 'fuel packages' for use in models to 

meet assessment objectives. Below is the outline of 

the selection process and examples of generic studies 

that can be conducted for supporting the tool 

selection process. As described in the previous 

section, these studies ultimately have to be based on 

cases representing a given application, as results of 

such studies are highly dependent of the given 

application definition and context. 

Process outline and generic „test bed‟ environment 

for guiding selection of the right tool for a given 

application 

In this effort we aim to demonstrate that by applying 

a specific process for a set of „test bed‟ building 

configurations of a particular use (categorized by 

building occupancy groups), for a particular range of 

configurations (determined by design fires scenarios) 

targeting a particular outcome (safety objectives 

including life safety, property protection, business 

continuity, etc.), the results of each „test bed‟ study, 

defined in that context, will yield data which will 

lead to a guideline of the selection of appropriate 

tools for that type of situation. 

1 The difference between the existing SFPE Guide and the 

proposed approach is that the existing guide helps to justify 

use of a tool, once selected, and the proposed approach 

helps guide selection of an appropriate tool. 

The reason for collecting ranges of buildings by 

building occupancy groups is to obtain an extensive 

database of information related to layouts of 

representative buildings, rather than individual 

building layouts, which can then serve as the basis of 

guidelines that are occupancy group based (e.g., 

guide to application of fire effects tools in healthcare 

occupancies). Also, in a broader context, determining 

the building occupancy group is the first step in 

assessing its fire protection requirements whether one 

follows prescriptive building regulations or the 

performance-based design process (a first step being 

to define the scope of the project, notably by 

identifying the intended use and occupancy of the 

building (SFPE, 2007b)). 

The process that is envisaged to conduct a „test bed‟ 

study case is composed of the following steps: 

1.	 Identify occupancy group for study focus 

2.	 Collect building configurations for study 

3.	 Identify study parameters (e.g., selection of tool 

for assessing safety objectives) 

4.	 Set up building layouts for fire effects (zone 

models, CFD models) and their evacuation 

counterpart 

5.	 Identify objectives and criteria (life safety, 

property protection, mission continuity) 

6.	 Select fire scenarios for study (additional 

guidance in other work) 

7.	 Perform the fire (and evacuation) simulations 

with the different sets of tools (and for different 

mitigation strategies, as appropriate) 

8.	 Analyze the results in terms of the safety 

objectives 

9.	 Assess ability of tool to address defined 

performance issue 

10.	 Conclude by establishing guidelines related to 

the tool comparison process and its outcome. 

With respect to the „test bed‟ studies, it is important 

to note that each individual case does not need to be 

validated; that is, the objective of performing the case 

studies using different tools is not to increase the 

validation domain of the tools, but to obtain 

information about the application of the different 

tools for attaining different objectives. Likewise, the 

case studies themselves do not result in de facto 

design fire scenarios for the considered building 

occupancy group. These two objectives (increasing 

the validation domain of tools, selecting fire design 

scenarios for performance-based applications), while 

important to the overall process, are out of the scope 

of the studies presented in this paper. Cf. (Alvarez 

and Meacham, 2011) for more information. 

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Also, it is important to have participants undertaking 

the case studies from across the whole spectrum of 

the fire engineering community – from consulting 

engineers to regulators, and by engineers and 

regulators from around the world. Such diversity and 

breadth of participation would provide the potential 

to add more tools, more fire scenarios, and more 

variants in the building configurations, and the 

resulting „test bed‟ study guidelines would be more 

directly included in the larger performance-based fire 

protection design framework. (Having 20 engineers 

from 10 countries apply tools and fire scenarios that 

they select for a common set of objectives for a set of 

5 healthcare configurations would yield much more 

robust data than 2-3 engineers applying the same tool 

to a single building configuration.) 

While processes similar to the above exist at a 

generic level (e.g., SFPE Guide to PerformanceBased Fire Protection) they lack the detail and the 

data to help users make informed judgments. This 

approach aims to both provide added detail to the 

process and data to support the justification of the 

tool selection. 

Specific case studies: issues related to the use of 

CFD fire effects tools 

The use of CFD fire effects tools is quite complex 

and necessitates that the user also deals with 

uncertainties related to the use of these tools. Here 

are some examples of issues related to the “user 

effects” related to CFD fire effects tools – issues that 

would have to be addressed when using this kind of 

tools in Step 7 of the „test bed‟ study process. 

Grid selection for a better optimization of 

computational meshes of a CFD fire effects tool 

Spatial domain can be categorized as one source of 

"user effects" uncertainty (SFPE, 2011). For a CFD 

fire effects tools, grid sensitivity should be performed 

in order to determine at what grid refinement the 

desired outcomes become grid independent. 

However, care should be taken to assure other design 

objectives are met as well. 

For example, Sztarbala (2011) indicates that "when 

LES model is used, the number of grid elements must 

be increased. A maximum edge length of 0.15 m is 

recommended for grid elements in flow-relevant 

areas. For other areas the maximum edge length 

should not exceed 0.50m". However, these grid cell 

sizes may not be compatible with the time and 

computing resources of FPEs in the consulting 

environment, as they would require extensive parallel 

processing power and memory. In addition, these grid 

sizes may not be needed for the resolution of analysis 

required. In addition, some CFD tools allow the 

definition of multiple meshes with different grids, 

which allows some flexibility. However, 

communication between the different grids may 

affect the results. Looking at this issue in a more 

comprehensive manner can lead to developing user 

guidance when designing for all computational grids. 

Influence of detailed geometry on the results of the 

simulations 

It is known that the computational mesh, which 

simulates the spatial domain of the project of interest, 

has an influence on the results provided by CFD fire 

effects tools. However, there is no real guidance on 

how to deal with this issue. For specific outcomes of 

fire scenarios, it may be necessary to perform a 

simulation with a high level of details. Because of 

calculation time it would require, such simulations 

which include details of building contents and 

structural elements are rarely performed in practice 

because they are not compatible with the time 

constraints of engineering studies. To address this 

issue, it would be beneficial to establish guidance on 

the degree of detail needed for particular design 

aspects (e.g., contents, structural features) that are 

"just" needed with respect to the degree of details 

required in the description of the building geometry. 

Looking at this issue would help to: 

- indicate whether the simulation of all a building 

in 3-D is necessary, 

- determine the minimum degree of details needed 

to get access to the information, describing 

temperature profiles, smoke and toxic fire 

effluent propagation required to perform an 

analysis of the evacuation of building occupants. 

In addition, by looking at different safety objectives 

for the same building configuration, one could verify 

if the building description established for an occupant 

evacuation could be used for design fire scenarios 

related to property protection or business 

interruption. 

Detailed geometry description v. computational time 

and result accuracy 

CFD fire effects tools allow a refined description of 

the building structural elements and contents, which 

represent heat sinks and obstacles that can modify the 

buoyant smoke and hot gases trajectory. Whereas 

these structural elements and contents can be 

described in detail in 3-D simulations, and these 

details may influence the results of the simulations, 

but at a cost of an increased computational time, a 

series of simulations should be performed in order to 

estimate how the detailed geometry description affect 

the result accuracy to the detriment of computational 

time. 

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Verification of the consistency of results 

As indicated in Chapter 5 of the SFPE Guidelines for 

Susbtantiating a Fire Model for a Given Application 

(verification and validation), using multiple tools for 

the same configuration may demonstrate that the 

"results make sense. Especially for more complex 

models, performing an analysis with another tool 

could result on a non-sensical result" (SFPE, 2011). 

While this kind of analysis is not a primary objective 

of the „test bed‟ studies presented in this paper, 

results from the „test bed‟ studies of fire effects tools 

for a given application can serve as a basis for a 

verification of the consistency of results between 

different types of tools. 

Inclusion of Hybrid modeling in the „test bed‟ 

studies 

As presented previously, attempts have been made to 

create hybrid tools which can combine the accuracy 

of the CFD model with the computational speed of 

zone models. Other recent examples of such hybrid 

tools for estimating fire effects concern: 

- the simulation of large geometries such as large 

buildings or large passenger ships, with a CFD 

model / zone model hybrid developed by the 

University of Edinburgh (Burton et al, 2011), 

- the estimation of HVAC flows in case of fire in a 

building based on a coupling of a HVAC 

network model with the Fire Dynamics 

Simulator (FDS) developed by Floyd (2011). 

Hybrid tools appear to be promising new tools, which 

can also be included in the „test bed‟ studies 

presented above. It will also be important to analyze 

the process the hybrid models underwent so to collect 

information not only about the computational time 

gain with minimum accuracy loss, but also the 

assumptions related to the fabrication of the hybrid 

tools as these assumptions may be highly dependent 

on the applications of the tools, that is to say the set 

of configurations the tools were designed for. 

ORGANIZATION OF THE „TEST BED‟ 

STUDIES 

As presented above, the first steps in the process are 

obtaining layouts for occupancy groups and defining 

analysis objectives. Once this has been done, the 

analysis starts with setting up the building layouts. 

Setting up building layout (Step 4) 

The following process for generating building layouts 

for FDS from different building configuration 

sources has already been established and is presented 

below. 

Process to generate “ready-to-use” building layouts 

for Fire Protection design purposes 

Architects design the overall building layout using 

3-D software that is able to render the geometry of 

the rooms, spaces and exit pathways. Furniture and 

building contents, as well as nature of the structural 

elements would be described in this software files. 

Architect engineers dealing with the description of 

the building systems, such as the HVAC system, also 

describe their data using 3-D software. To facilitate 

the „test bed‟ studies of real building geometries for a 

range of occupancy groups, it would be helpful to 

have a set of „ready-to-use‟ building layouts. The 

process in order to get these layouts for FDS 

simulations, from architect design files, is described 

in Figure 2 below. 

Figure 2:	 Process currently followed to create FDS 

building layouts. 

In the 8th International Conference on Performancebased Codes and Safety Design Methods (SFPE, 

2010) the case study was related to a 6 story office 

building where 4 stories had to be converted into a 

night club. Table 1 presents the different fire effects 

and evacuation tools used by the participating 

countries. Compiling the building layouts presented 

in Table 1, as well as the fire scenarios selected by 

the different countries would constitute a fast way to 

carry the 1st tasks of a „test bed‟ study case related to 

that configuration. 

Table 1:	 Fire effects tools and evacuation tools 

used by different countries (SFPE, 2010) 

Country Fire effects Evacuation 

New 

Zealand 

Zone model 

(BRANZFIRE) 

Algebraic models 

USA CFD model (FDS) Algebraic models 

Australia Zone model (CFAST) PATHFINDER 

France Zone model 

(CIFI2009) and CFD 

model (FDS) 

Algebraic models 

Hong 

Kong CFD model (FDS) MODELMAKER 

Japan Algebraic models and 

zone model (BRI2002) 

SimTread 

Sweden CFD model (FDS) STEPS 

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In addition, other potential sources of building 

layouts are NIST investigation reports (Station 

nightclub, office building of the Cook County 

hospital or part of the World Trade Center) or 

published articles including building layouts for 

estimating fire consequences or even crowd 

evacuation. 

Going forward, however, it would be helpful to 

obtain building layouts, from architects, which 

represent a wide range of building configurations 

over a spectrum of building occupancy groups. 

Table 2 presents a list of building configuration 

layouts to be implemented in the near future, with a 

focus on getting the description of the spatial domain 

in FDS. 

Table 2:	 List of building configuration layouts to 

be implemented in the near future 

Building occupancy type Example 

Assembly Library 

Heath care Hospital 

Educational High school 

Residential Dormitory 

Examples of building layouts are included in the 

conference presentation slides. 

To facilitate use by a broad range of stakeholders, the 

building layouts will ultimately be distributed to a 

Google user group to be tested across the world (as 

materials and fire protection features vary with 

countries) and versions of these layouts usable for 

other fire effects tools as well as for evacuation 

modeling will also be developed. Before the end of 

the year, the layouts will be distributed to a small 

group of fire protection engineers across the world 

for some feedback. It should be noted that these 

configurations will not include any fire components 

or fire protection features. The information gathered 

in the Google user group on the building 

configurations is aimed to be as exhaustive as 

possible in describing the building contents and 

occupants so to remain accessible and usable even for 

upgraded versions of the currents tools or future 

tools. 

Selecting fire scenarios (Step 6) 

Whatever the fire effects tool, be it based on 

algebraic models, zone models or CFD models (when 

not using a pyrolysis model), the description of the 

fire remains a user input data of crucial importance. 

A primary component of the fire design scenario is 

the fire design curve which represents the evolution 

with time of the heat release rate (HRR) of the 

corresponding fire. This “HRR curve” will allow the 

calculation of the heat hazard component of the fire. 

In parallel to the evolution with time of the HRR, the 

evolution of the fire effluents (smoke, toxic and 

irritant products) is also essential to estimate the toxic 

hazard component of the fire. 

When using fire effects tools, two options for 

establishing the HRR curve are possible: 

- the HRR curve can be predefined, from ignition 

to extinguishment, and used as an input for all 

the different types of fire effects tools, or; 

- the HRR curve can be left to the different fire 

effects tools estimate as follows: the location and 

nature of the 1st burning item are given and the 

tool has to assess fire propagation to the other 

fuel items which nature and position are known. 

Whatever option is selected, and because no 

pyrolysis model is intended to be used in the present 

scope of the „test bed‟ studies, the user has to provide 

HRR curves for single fuel packages, describing the 

evolution of the HRR they can individually produce 

once ignited. 

HRR curve database 

When looking for heat release rates for building 

contents, from furniture to curtains, from appliances 

to even cars, a primary source of information is the 

SFPE Handbook chapter dedicated to heat release 

rates, written by Babrauskas (2008). This chapter 

contains numerous references that can lead to a 

significant amount of data from furniture 

calorimeters, including heat release rates evolution 

with time, soot and toxic component yields. In 

addition, by reviewing NIST publications alone, 

some fifty different experiments have already been 

included in a database, along with the available 

snapshots and videos. This number will be expanded 

by looking at more NIST studies, as well as tapping 

into test data from around the world. Before the end 

of the year, it is planned to distribute the database to 

a small group of fire protection engineers across the 

world for feedback and contribution to the database. 

Smoke and fire effluents 

Smoke and fire effluent production and movement 

quantification are an important part of the 

engineering problem, related not only to life safety 

objectives, but also to property damage, and 

environment protection. Products of combustion can 

have an impact on people safe evacuation (affecting 

their safe escape), on building contents (damaging 

costly pieces of equipment or historical artifacts), on 

business continuity (causing the malfunction or the 

destruction of manufacturing goods, processing 

chains, or equipment assuring the safety of the 

process), or on the environment (when toxic or 

hazardous materials are released in quantities that can 

impact the environment). Thus, it is essential to 

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estimate the nature and the kinetics of the fire 

effluents. 

In solving engineering problems related to fire 

effluent impact on building occupants and contents, it 

is necessary to assess the production, transport and 

deposition/absorption of these effluents inside the 

building and also outside for environmental safety 

objective. Transport and deposition of airborne 

particles constitute very complex subjects by 

themselves and these phenomena are greatly 

influenced by the building layout, which adds another 

study to the ones already presented in the previous 

sections dedicated to the building layouts. Production 

of fire effluents are related to the fire spread on the 

burning combustibles, which include the also 

complex pyrolysis processes of usually 

heterogeneous materials, as well as the ventilation 

conditions around the fire scene (i.e. the fire is underventilated or not). 

When reviewing NIST furniture calorimeter tests, it 

was noted that the information related to the 

production of fire effluents was rarely provided. 

Additional information may be collected when 

material properties are collected, i.e. at laboratory 

scale, such as soot yields, CO yields, CO/CO2 ratios, 

etc., if possible for pre-flashover and post-flashover 

conditions, as these values are dependent of the 

ventilation conditions around the burning fuel item. 

„Combustible packages‟ for 3-D simulations 

The objective of providing 'combustible packages' 

ready for 3-D simulations came from the FDS user 

point of view and the availability of third party 

software developed in order to facilitate the creation 

of FDS input data files. Indeed, if such software is 

able to create and duplicate building elements as 

presented in the previous section, why not trying to 

do the same for combustible elements. 

For FDS, the heat release rate is defined by a surface 

area, that is to say, that the specification of the 

burning areas is required. Because of this 

requirement, the evolution with time of the burning 

areas has to be included as an input data. In some 

cases, the burning area is set up as a constant and at 

the maximum of the combustible object area(s). 

Nevertheless, for complex setups of combustible 

building contents, which have been burnt in furniture 

calorimeter, videos clearly show the flame 

propagation from the ignition localized point to the 

complete flame engulfment of the set up, which can 

occur several minutes later as a peak of HRR. 

The description of the flame spread over the 

combustible building content is necessary when 

assessing the fire spread inside the compartment or 

space where the content is located, as the estimation 

of the ignition of the second burning item is 

dependent on the radiation received by this target 

1st from the burning building content. This heat 

transfer mechanism can be estimated using a CFD 

fire effects tool so it requires the flame characteristics 

which are dependent on the evolution with time of 

the HRR and of the burning areas. It should be noted 

that such a detailed characterization is not required in 

the far field, that is to say when the given application 

is related to the phenomena that occur outside the 

room of fire origin, i.e. for example when assessing 

the smoke spread in exit pathways outside the room 

of fire origin. The degree of details for the 

'combustible packages' is also dependent of the given 

application, as well as the other input parameters 

presented in the previous sections. 

Even for relatively simple building content geometry, 

such as a wood dresser, the question of the burning 

areas remains: if all the HRR is distributed at the top 

area of the wood dresser, activation of a heat detector 

would be quicker than if the HRR is distributed on 

the lateral areas of the wood dresser. In the latter 

distribution, ignition of a second burning item located 

in front of the wood dresser would be quicker. 

Since some snapshots and videos are available from 

the NIST for different building contents including a 

wood dresser, it was then decided to study the 

influence of the burning areas evolution with time on 

the ignition of a second burning item and on heat 

detection at the ceiling level. 

NIST/BFRL experiments related to the combustion 

of a loveseat, a mattress (with center ignition and 

corner ignition) and a wood dresser were selected. 

Burning areas were defined according to the flame 

spread pattern on the burning item. Fractions of the 

HRR were then distributed among the defined areas 

so the resulting modeled flames would have the same 

length as the ones in the snapshots or video. In the 

corresponding FDS simulations, devices were located 

in front and at the periphery of the burning item and 

temperatures were recorded under the ceiling to 

estimate the activation time of thermal elements 

located there. 

Detailed analysis of the results will be available in 

the near future. Even so, thus far the particular study 

shows the feasibility of such a detailed description of 

combustible burning items. By the end of the year, a 

primary series of 'combustible packages' will be set 

up and distributed to a small group of fire protection 

engineers across the world for some feedback. 

Examples of „combustible packages‟ for FDS are 

given in the conference presentation slides. 

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Creation of a fire protection engineering 'test bed' 

study pool (Step 7 to Step 10) 

Performing Step 7 and Step 8 of the „test bed‟ study 

process requires significant time and resources to 

collect the targeted data. It is not feasible for a single 

entity from within the fire protection engineering 

community to conduct all the needed studies – not 

only from a resource perspective, but because each 

sector within the FPE community has its own goals 

and objectives, prerogatives and time and resources 

constraints. In addition, Steps 5-10 require 

participation of people from all sectors in any case. 

Conducting such studies with all these different 

people would benefit all of them in different 

manners: 

- The consulting companies would acquire better 

understanding of the use of tools for a given 

engineering application, optimizing their 

resources and time; 

- The students and professors in Academia could 

use the case studies as practical examples of 

engineering problems; 

- The governmental agencies could set up research 

programs focusing on the problems and needs of 

the engineering community; 

- Engineering societies could elaborate guides and 

guidelines improving the use of engineering 

tools for given applications, where appendices 

would be added with the results of specific cases; 

- Regulators and Authorities having jurisdictions 

would consider the improvements in the use of 

tools in projects based on performance based 

design fire protection options. 

The aim, then, is to encourage the establishment of a 

sector-wide and world-wide group of users to 

participate in the 'test bed' studies outlined above, 

with the objective of developing data which will lead 

to a guideline for the selection of appropriate tools 

for specific building occupancy types and 

configurations. 

REFERENCES 

Alvarez, A. and Meacham, B. J. (2011), "Towards 

the next generation of performance-based fire 

protection design for the built environment", 

manuscript to be submitted for publication in 

September 2011 

Babrauskas, V. (2008), "Heat Release Rates," SFPE 

Handbook for Fire Protection Engineering, 

4th edition, section 3, chapter 1, (3)1-(3)59 

Barrachin, G., Chaussard, M., Bertrand, R., 

Bonneval, F and Mattei, J.M. (2000), "Insights 

from the Blayais 1 NPP Fire PSA," Proceedings 

of the 5th International Conference on 

Probabilistic Safety Assessment and 

Management, volume 3/4, 2093-2098 

Burton D., Grandison A., Patel M., Galea E., Ewer J. 

(2011), “Development of a Hybrid Field/Zone 

Fire Model,” Proceedings of the Tenth 

International Symposium of IAFSS 

Collela, F. (2010), "Multiscale Modelling of Tunnel 

Ventilation Flows and Fires," British Research 

Establishment PhD thesis collection 

Floyd, J. (2011), “Coupling a Network HVAC Model 

to a Computational Fluid Dynamics Model 

Using Large Eddy Simulation,” Proceedings of 

the Tenth International Symposium of IAFSS 

Society of Fire Protection Engineers (SFPE) (2007a), 

Guide to Predicting Room of Origin Fire 

Hazards 

SFPE (2007b), SFPE Engineering Guide to 

Performance-Based Fire Protection 

SFPE (2010), Proceedings & Case Studies of the 8th 

International Conference on Performance-based 

Codes and Safety Design Methods 

SFPE (2011), Guidelines for Substantiating a Fire 

Model for a Given Application 

Siu, N. O., Hyslop, J. S. and Nowlen, S. P. (2008), 

"Fire Risk Analysis for Nuclear Power Plants," 

SFPE Handbook for Fire Protection Engineering, 

4th edition, section 5, chapter 14, (5)258-(5)273 

Sztarbala, G. (2011), "Computational Fluid 

Dynamics as a tool of fire engineers – good 

practice," Presentation at Eurofire 2011 

INFORMATION 

This work is supported by grant 60NANB10D228 

from the US National Institute of Standards and 

Technology. 

9 
 

 

 

 

 

 

 

 

 

 

Appendix A3
 

'Test bed' environment process for assessing the appropriateness of engineering tools
 

to be used in performance-based design applications
 

presented at the 9th International Conference on Performance-Based Codes and Fire Safety Design Methods, 

in Hong Kong, 20-22 June 2012.
 

Reprinted with permission of the Society of Fire Protection Engineers 

Original source: 

Alvarez, A. and Meacham, B.J., "'Test bed' environment process for assessing the appropriateness of engineering 

tools to be used in performance-based design applications" in: Proceedings of the 9th International Conference on 

Performance-Based Codes and Fire Safety Design Methods, 20-22 June 2012, Hong Kong, 2012, Society of Fire 

Protection Engineers 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

'Test bed' environment process for assessing the appropriateness of 

engineering tools to be used in performance-based design applications 

Alberto Alvarez and Brian J. Meacham, Ph.D., P.E., FSFPE
 

Department of Fire Protection Engineering, Worcester Polytechnic Institute,
 

100 Institute Road, Worcester, MA, 01609, USA
 

TOPIC 

There is a need for guidelines to aid the selection of appropriate fire consequence analysis tools 

for specific types of fire protection engineering applications. This is not to be confused with the 

recent SFPE Guide [1], which aims to help engineers justify (substantiate) why they selected a 

particular tool, but rather, to help engineers choose wisely before analysis begins. Within the fire 

community, the primary beneficiary of such guidelines is the fire protection engineer who 

applies the tools (dedicated to assess fire effects, evacuation processes and response of 

structures) and analyses the results in terms of safety objectives. However, other stakeholders 

involved in evaluating and accepting the performance of a building or structure to withstand the 

fire risk, such as building owners or managers, other members of the design team, insurers and 

authorities having jurisdiction would also benefit, since part of the evaluation/acceptance process 

is based on the analyses performed using the aforementioned tools. Researchers from academia, 

the government or the private sector who are involved in developing such tools would also 

benefit from the guidelines as they would re-enforce the link between the scientific research 

domain and the engineering application field. The need for such guidelines, and a structure for a 

'test bed' environment for assessing the appropriateness of tools for different engineering 

applications, is discussed. 

PROBLEM CONTEXT 

In general, performance-based design approaches for fire protection design require: 

1. The definition of goals, objectives, performance criteria, 

2. The selection of fire design scenarios upon which trial designs are evaluated, 

3. The assessment of the consequences of the fire design scenarios using fire effects tools (and 

evacuation tools...) that are selected according to the needed degree of analysis. 

In order to assess consequences (third point), input data that describes the considered built 

environment and the fire scenarios is required. Tools that are currently used for fire consequence 

analysis address a range of phenomena: for example, fire effects (temperature increase, 

production and movement of smoke and toxic effluents, loss of visibility), occupant response and 

movement (occupant behavior and travel speed), and material, equipment and structural response 

to fire. In addition to the range of tools available, the tools have different levels of sophistication 

in being able to incorporate more or less detail, e.g., more or less physical phenomena for the fire 

effects tools, more or less psychological phenomena for the evacuation tools, and more or less 

details of the considered built environment components and systems for the structural response 

tools. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Guidelines have recently appeared to help the fire protection engineer "substantiate a fire model 

for a given application" [1].This is in addition to guidelines that help the engineer understand the 

performance-based design process [2] and one which assists code officials in the review of 

performance-based designs [3]. In addition, websites are emerging which bring together users 

and developers of various fire engineering tools. This includes a site focused on Fire Dynamics 

Simulator (FDS) from the US National Institute of Standards and Technology 

(http://groups.google.com/group/fds-smv) and a site focused on users of evacuation models 

(http://www.evacmod.net/). Such sites and the people who use them collect considerable 

information related to the use of these tools. The International Conferences on PerformanceBased Codes and Fire Safety Design Methods, managed by SFPE, have been presenting case 

studies where fire protection engineering national teams provide their analysis. 

However, linkages between the guidelines and websites on processes, applications, data, and 

tools are lacking. In addition, there is significant diversity in the scenarios and buildings being 

used for developing and testing tools and methods. If better linkages are made, and a set of 

comprehensive „test beds‟ can be developed – which can be used for testing all types of fire 

engineering tools – for a variety of applications – there are significant benefits to be realized by 

those who develop, use and review the tool applications. 

This paper introduces a new holistic approach related to the selection of engineering tools to be 

used in performance-based fire protection design applications. When completed, this approach 

will differ significantly from current practice, taking into consideration not only tools for 

modeling fire phenomena, but also tools for modeling building occupant evacuation, structural 

response and even risk analysis. In addition, the context for use of the tools will be integrated in 

the method for selecting appropriate tools. 

DEVELOPING A NEW HOLISTIC APPROACH FOR SELECTING TOOLS TO BE 

USED IN PERFORMANCE-BASED FIRE PROTECTION DESIGN APPLICATIONS 

For performance-based fire protection design (PBFPD) applications, engineering tools are used 

to assess the outcomes of the design fire scenarios. In the past decade, fire protection engineering 

appeared to have left its infancy stage, as it started to incorporate scientific elements from 

outside its core fundamentals (i.e. fire science), from toxicology, human behavior, computing, 

statistics, etc. The result is that the fire protection engineer has a wide range of tools available for 

PBFPD applications, as outlined above. Since arguably more work has been carried out 

concerning development of fire effects tools than the other types of tools, the initial focus of this 

work is on fire effects tools. 

Assessing appropriate applications of fire effects tools 

In the USA, significant efforts have been undertaken in recent decades regarding uses, 

applications and limitations of fire effects tools, mainly originating from a collaborative project 

initiated by the US Nuclear Regulatory Commission (NRC), which led to an extensive series of 

reports [4], freely available spreadsheets and more. The SFPE Guidelines for Substantiating a 

Fire Model for a Given Application [1] was based on this body of work. The SFPE Guidelines, 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

recently published, not only includes an extensive appendix related to the fire-related phenomena 

which are relevant to PBFPD (such as gas layer temperature and depth, heat flux or gas 

concentrations) but it also notes the need to identify elements that of concern to the considered 

design fire scenarios for PBFPD applications [5], for example: 

- Details of the spatial domain representing the built environment, 

- Fire design scenario timeframes (from several minutes for a single room flashover
 

application to several hours for assessing the collapse of a structure due to a generalized fire), 

- Material properties not only describing the combustible contents but also the other building 

elements which "absorb" heat and fire effluents as well as the load-bearing elements, 

- Initial and boundary conditions, including initial temperature in and outside the built 

environment and the ventilation conditions (initial conditions including the window and 

doors status (opened or closed) as well the boundary conditions (how the doors are leaking or 

how the mechanical ventilation network is set up). 

Chapters related to verification and validation of fire effects tools, as well as the user effects and 

documentation, nicely complement the key aspects that a Code's Official is looking for when 

assessing a PBFPD report [3]. 

While these recent works are all helpful, it is worth noting that concerns related to 

appropriateness of tools used in PBFPD appeared as early as the developments of these tools and 

the PBFPD methods themselves. For instance, in 1992, Friedman [6] dealt with how well a 

model could predict quantities, what procedures would have to be followed to assess the 

accuracy of a model. He proposed two options to perform such a task: 

1.	 The first one is to express the accuracy of a model as a percentage deviation of prediction for 

measurement. Using that option would arise problems related the cost of performing 

necessary full-scale tests, assessing the errors of the experimental devices as well as the poor 

reproducibility of such tests due to the stochastic nature of the fire phenomenon; 

2.	 The second option is to focus on the capability of a model to answer the following questions: 

will the second combustible item ignite? Will a relatively small fire be able to actuate a 

nearby sprinkler? Will toxic conditions in a corridor near the fire compartment be such as to 

prevent escape through the corridor? Will an exposed beam fail, causing collapse? 

As Fire Protection Engineers, we are more concerned about the second option and how confident 

we would be in answering the aforementioned questions, in a holistic context regarding the fire 

safety of a building. The first option is related to the verification process and it is undeniable that 

FPEs would prefer to support their analysis with using a model which describes fire phenomena 

as closely as possible. Nevertheless, the second option is still FPE prime concern as recognized 

by Friedman: even if a "perfect" model able to describe the reality of the fire phenomena existed, 

uncertainties in the input parameters, which the users had to select, would introduce a decrease in 

the reliability of the model to answer the questions in point 2 above with an a clear "yes or no". 

Examples of uncertainties in the user input parameters are: the composition of the combustible 

items, which would influence the evolution with time of the heat release rate and the production 

of smoke and toxic effluents, the percentage of absorbed moisture, which would influence the 

thermal inertia of a gypsum board. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Friedman stated that the decrease in the tool reliability could be as low as 50% (random guess) as 

illustrated in Figure 1a, when considering a single input parameter. For an actual tool, which 

itself bears uncertainties in terms of the simplification of the physical world and use of numerical 

techniques, Figure 1b shows that the uncertainty range due to a single input parameters gets 

bigger. Reliability (%) of Yes/No

100 

50 

0

prediction of a

"perfect" model

Reliability (%) 

of Yes/No

prediction of an 

actual model 100 

50 

0 

a) b) 

Figure 1: Reliability of the predictive capability of a model to clearly state "yes or no" 

to an engineering question, as a function of single input parameter values, a) for a 

"perfect" model and b) for an actual model [6] 

In 2002, Mowrer [7] used a similar concept to describe the capability of a tool to clearly state if a 

performance criterion used in the PBFPD option has been achieved or not. This time, the range 

of uncertainties is associated with the power of the analytical tools (i.e. the capability of the tools 

to simulate the fire phenomenon). His concept is presented in Figure 2, where he stated that the 

perfect analytical tool would be the one that eliminated the uncertain middle area. His point of 

view differed from Friedman's one for addressing the concept in Figure 2, but he joined 

Friedman in stating that "perhaps the worst mistake a fire modeler can make is to run a model 

only once and then rely on those results as conclusive without considering how variations in 

input parameters might affect the results". 

Performance criteria Performance criteria 

clearly achieved clearly not achieved 

Simple tools 

adequate 

More powerful tools may be 

useful to reduce uncertainties 

Simple tools 

adequate 

Not clear if 

performance criteria 

clearly achieved 

Increasing 

power of 

analytical 

tools 

Figure 2: Ideal representation of calculation results as a function of the increasing 

power of the analytical tool employed [7] 

Nevertheless, by mixing Figure 1 and Figure 2, the following concept emerges: (a) there are 

ranges of input parameters to be used in conjunction with simple tools that allow the fire 

protection engineer to clearly state if a performance criterion is achieved or not, so that (b), for 

the cases delimited by the ranges of all input parameters, it would be possible to use even the 

simplest tool to perform an engineering analysis, without sacrificing any certainty concerning the 

achievement, or not, of the performance criteria, and (c) for the other cases, the use of more 

"powerful" or more complex tools would reduce the uncertainties when dealing with 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

configurations not covered by the simple tools. Furthermore, (d) the transition between the two 

cases (from the case where the performance criteria are clearly achieved, or not to the case where 

they are not clearly achieved) is where a switchover analysis, related to the use of the tools 

(Mowrer's concept) in addition to the one related to the values of the input parameters of a tool 

(Friedman's concept), should take place.1 

Tools are only as accurate as their weakest link: developing the design fire curve 

It is not surprising that the most influential parameter of fire effects tools is the design fire curve, 

which "usually establish[es] a relationship between heat release rate and time"[2], as it is the 

generating driver for temperature increase, smoke and toxic effluent production that ultimately 

impact targets such as building occupants, contents and structure. 

SFPE [2], for example, indicates that "several methods can be used to define a design fire curve: 

using published data, fire testing, or calculating a theoretical fire size. In a fire protection 

engineering design, it can be useful to consider more than one of these methods". It should be 

noted that some of these methods are based on a series of standardized tests because there was 

always a need to connect test data serving to characterize materials with scientific data used for 

engineering calculations. Indeed, fire rating elements (door, floors...) cannot be tested according 

to every possible design fire curve. 

Let's consider, for example, how fire propagation from a burning item to a combustible: there are 

some empirical correlations and procedures which allow quick estimations of the possible 

ignition of a second fuel source from the radiation emitted by a first fuel source. The 

International Fire Engineering Guidelines (IFEG) [8] identifies the following methods: 

- Mikkola and Wichman (1989) consider both thermally thin and thermally thick materials, 

- Tewarson (2002) requires data related to the TRP, or ignition temperature and some 

material characteristics, in order to calculate delay before ignition 

- Quintiere and Harkleroad (1985) used LIFT data in a simplified thermally thick solution, 

- Toal et al. (1989) used cone calorimeter and ISO Ignitability Apparatus, 

- Babrauskas (1981) performed series of tests burning combustibles and established three 

different curves relating the ignition distance of the second burning item to the peak mass 

loss rate of the first one and according to the second item ignitability. 

Based on the review of these elements, it seems that the most sophisticated fire effects tools 

(existing so far) are still dependent on the user evaluating, on his/her own, the most influential 

parameter of fire effects tools: elaboration of the design fire curve prior to its introduction into 

the tool as an input file. 

Switchover analysis is one of the many types of evaluation techniques accounting for known variations and 

unknown effects [2], so not only this concept established above is useful for tool selection but also could serve as a 

basis for establishing sets of tool input parameters which lead to a switchover of the analysis conclusion. 

1 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Assessing appropriate applications of tools for solving PBFPD problems: the technical 

layer 

Another layer of complexity appears when considering that not only are fire effects tools used to 

estimate the outcome of a design fire scenario, but also: 

- evacuation tools are needed when assessing whether life safety performance criteria are 

achieved, and 

- structural response tools are needed when assessing whether a built structure would 

withstand the design fire scenarios. 

Comparison between the required safe egress time (RSET) and the available safe egress time 

(ASET) is widely accepted as an approach when dealing with time-based egress calculations. In 

the ASET/RSET approach, calculations regarding the "fire" side (ASET) and the "people" side 

(RSET) are usually performed separately. Fire Protection Engineers have to estimate the time 

before untenable conditions are reached versus the time required for the building occupants to 

safely evacuate and manually assess interactions. Using different tools to assess both times, and 

relying on the engineer to integrate the outcomes, results in concerns and constraints as well. It 

should be noted that research tools such as FDS+EVAC allows simultaneous calculations of fire 

propagation and evacuation process, Building_EXODUS allows input from the fire effects tools 

SMARTFIRE and the evacuation software STEPS allows input from the fire zone model CFAST 

and FDS. Nevertheless, even with these most elaborate tools, not only the influence of the fire on 

the people ability to evacuate still needs more integration, mostly about decision making, but 

also the effect of people actions on the fire needs to be modeled within these tools. 

Looking at the pre-movement time, for example, there is a "large" range associated with the time 

occupants take before starting their evacuation, as illustrated in Figure 3. The time when people 

receive the first clue that a fire event is occurring is also based on a distribution rather than a 

single value, as people can be notified by various means other than a smoke alarm, or centralized 

fire notification system connected to the automatic fire detection system. 

Figure 3: Pre-movement time reported after the fire in the Cook County 

Administration fire, October 17, 2003 Chicago, IL [9] 

Mixing the estimation of the RSET and the ASET in a probabilistic risk assessment, authors have 

come out with the schematic representation of Figure 4: f(t) the probability density distribution 

function of individual evacuation time. fA(t) is the probability density distribution function of 

ASET. This figure has been established considering uncertainties of the design fire curve and 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

f(t) 

fA(t) 

characterizing occupant pre-movement time as a normal distribution, as an analogy with the 

result presented in Figure 3. Chu et al. [10] stated that "two curves are overlapping which 

indicates there is a probability that untenable conditions may occur before all occupants evacuate 

to a safe place". 

Probability density 

time 

Figure 4: Hypothetical probability density distributions of individual evacuation 

time {f(t)} and ASET { fA(t) } [10] 

Looking at risk assessment would lead to different results when considering different tools, as 

the overlapping portions of the two probability functions may be different. The advantage of this 

type of result is that uncertainties are taken into consideration in the result shown to the AHJ, so 

we are now introducing the concept of probability of failure/success and not giving "absolute 

numbers" (this current situation then tends to increase the liability of the fire protection engineer 

as the AHJ is asking for some certainty of analysis outcomes, when in fact fire protection 

engineer is dealing with events that can potentially occur within a wide realm of possibilities). 

Assessing appropriate applications of tools for solving PBFPD problems: the usability layer 

Figure 5 illustrates the „usability‟ concept (right tool at the right time) for a fire protection 

engineer (FPE) dealing with a new building design project. In this concept, the use of tools 

needed to conduct analysis varies along the timeline of the project: 

- At the start of the project, in the feasibility and concept design phases, the level of detail in 

the analysis is quite low as the FPE can only provide an idea of the measures to install (based 

on the prescriptive requirements and the possible deviations to them) as data required to 

perform any analysis is still scarce. If fire effects tools are needed, algebraic models are 

mainly used, with a high calculation speed; 

- During the scheme design, data related to the interior design of the building becomes 

available and more sophisticated tools can then be used, such as zone models; 

- In the detailed design phase, the details of the project are known and 3-D simulations can be 

used – if needed and if time allows – as the time for analysis is shorter as we go along the 

project, running these complex simulations requires a considerable amount of time, 

compared to the use of previous tools, and since these tools generate a lot of useful 

information, data treatment of 3-D simulations is also time consuming. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Zone model use 

domain 

Algebraic model use domain 

Feasibility Concept 

design 

Scheme 

design 

Detailed 

design 

time 

Levels of details in the analysis

Availability of data

CFD 

model 

use 

domain

Calculation speed

Time for analysis 

domain 

Figure 5: Fire effects tools domains as a function of a new building project phases 

Figure 5 is applicable to the whole considered building project. If a specific safety point is 

known at the concept design phase, and if it is also known that the degree of details would 

require a more complex tool than an algebraic model or even a zone model, the FPE would have 

to somehow obtain, from the design team, the data needed in order to use such a more complex 

tool at the earlier stage. As stated previously, performing such calculations uses significant time 

and resources and the results are highly dependent on the input parameter values. Using input 

parameter values at the start, which in the end would be quite different from the ones that would 

be finally needed, could lead to dramatic changes in the design, not only of the fire protection 

features but also in the design of the building itself, and could mean expending considerable 

resource for limited value. However, if a set of 'test bed' studies existed, which reflect similar 

projects, the information could place the FPE in a better position to ask the design team for 

needed input parameter values, or at least range of values, based on the experience of the test bed 

studies. 

For PBFPD applications, another constraint that has to be considered appears in the regulatory 

environment. National standards, such as NFPA 204 for smoke and heat venting [11], NFPA 92 

for smoke control systems [12], and so forth may be used in conjunction with building code 

regulations, to help a project to be accepted by the Authority Having Jurisdiction (AHJ) because 

these standards are recognized by these AHJs. An engineering analysis incorporating the 

analytical methods of such standards would not require so extensive justification as the ones 

purely based on more sophisticated engineering methods. 

In conclusion, within a PBFPD framework, the selection of appropriate tools for a given 

application depends on many layers: 

- a technical layer where tools differ on how well they describe physical phenomena that are 

relevant to a given application, on how well the user has to consider the input parameters 

(mainly the design fire curve), how well the specialized tools communicate with each other 

(fire effects tools with evacuation models and so forth), 

- a usability layer where tools are used in a specific context, where input data may not be 

available as needed, analytical methods from already existing standards may be preferred to 

more sophisticated engineering methods based on their better acceptance by the AHJ. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

ORGANIZATION OF A 'TEST BED' ENVIRONMENT TO SUPPORT THE NEW 

APPROACH 

To address the challenges outlined above, a new approach is suggested in order to advance our 

ability to more appropriately apply the diversity of engineering tools that are available for the 

range of building fire challenges that FPEs face and the stage of the project at which the tools are 

needed. This approach involves two primary components: 

- Development of new guidelines for the selection of appropriate tools for a given fire 

protection engineering type of application, and 

- Development of a web-based „test bed‟ within which to apply, assess, evaluate and 

expand upon the capabilities of the tools and of the profession. 

Appropriate selection of a tool depends not only on its capabilities to “correctly” simulate the 

aimed physical phenomena, but also on the context in which the tool is used. At the same time, 

there is not always „unlimited time‟ to undertake analyses, and having prior knowledge about the 

appropriate applications for the tools can help increase the efficiency and effectiveness of 

performance-based analyses. In order to help the fire protection engineering community to be 

better able to address such resource and time constraints related to the use of fire consequence 

analysis tools, a process for tool selection and a „test bed‟ environment are proposed. The „test 

bed‟ environment allows a wide variety of tools to be applied to common building configurations 

and fire protection challenges in order to build up knowledge and experience on selection and 

use of tools for various levels of fire protection analysis. The „test bed‟ environment process is 

mainly composed of three following phases: 

1.	 A "pre-processing phase" where study topics are selected and organized according the 

common interest of different participants (including not only the usual stakeholders involved 

in PBFPD projects but also researchers and people in academia) and availability of input data 

and building layouts, 

2.	 A "performing and analyzing phase" where participants identify common safety objectives, 

safety functions and criteria, select together fire design scenarios to study with the tools and 

methods of their choice, upload the results to the website, 

3.	 A "post-processing phase" where results of the tool applications are discussed in terms of 

their ability to address the defined performance issue, which discussion would eventually 

lead to the establishment of guidelines related to the tool comparison process, their usability 

and their relative outcome. 

A more detailed process is presented in [5]. Each considered study topic will be associated with a 

portion of a website available to the 'test bed' participants, allowing free exchange of information 

and analysis. This organization is intended to maximize the number of participants and thus to 

contribute to a more extensive and validated study (with participants using differently the same 

tool so user influence would be addressed or with participants using different tools). 

In the pre-processing phase, building layouts are collected from existing architectural projects or 

fictional ones, as long as they provide enough information to be used from correlations to CFD 

tools. Additional information for evacuation or structural response calculations may be also 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

collected for use in upcoming hybrid tools such as the ones between a fire effects tool and a 

HVAC network model, as developed by Floyd [13]. During this phase, relevant information on a 

particular building or built environment is collected, including plans in AutoCAD® or REVIT®, 

interior layouts, and in some cases contents. Whatever tools are used by a fire protection 

engineer for his/her own purposes, these types of information are usually the basic information 

for the design team. Of course, as explained in the previous sections of this paper, not all the 

design information is available at the start of a project. Nevertheless, one of the primary aims of 

the „test bed‟ environment studies is to assess the differences in the tool answers in relation to an 

engineering problem. This pre-processing phase would then be used as a feedback for the design 

team so they would know what information/data to provide the FPE as soon as possible so the 

FPE could use it in his/her analysis, especially for tools that would require lots and precise input 

data. 

An initial „test-bed‟ environment has been set up already, and several building configurations 

have been obtained. Examples of already collected building configurations are: hospital, library, 

high-rise office building, high school and dormitory. To supplement this set of configurations, 

examples of case studies could also be collected from the International conferences on 

performance-based codes and fire safety design methods [14]. 

In recent years, extensive work has been done in order to facilitate the transfer from architect‟s 

files to files usable for CFD fire effects tools (FDS via the software PyroSim or SMARTFIRE), 

evacuation models (Building_EXODUS or STEPS). Besides this project and all the work carried 

out by the aforementioned tool developers, Pin and Wu also [15] considered the use of the 

imported CAD file (ge1 extension file) in order to visualize the results in the SMOKEVIEW 

tool. This paper led us to consider how this representation might be misleading for the 

stakeholders, while judging the results provided by FDS, which performs the CFD calculations 

and the SMOKEVIEW layer which helps presenting the FDS results in the 3D geometry: if the 

geometry of the building is shown as very refined, the AHJ could think that the FDS calculations 

are refined at that level, which is usually not the case. The import of the geometry has to be 

considered as only making the process easier and faster for the FPE to build the geometry for 

calculations. 

In the "performing and analyzing phase", which is really the core of the studies, safety 

objectives, safety functions and fire design scenario types are defined for each „test bed‟ study. 

Given this information, participants are asked to perform simulations with the tools of their 

choices and upload the results in the website, providing details not only on the results but also on 

the use of the tools. Specific studies related to the use of CFD fire effects tools are presented in 

[5], including issues related to grid selection for a better optimization of CFD computational 

meshes, influence of detailed geometry on the results of the simulations, detailed geometry 

description versus computational time and result accuracy. Some specific studies related to 

evacuation models may also be defined and conducted among the participants. 

In addition to studies related to the use of fire effects tools, studies related to the use of 

evacuation models, structural response models and fire risk models would also be included in the 

'test bed‟ environments. The website would also be dedicated to facilitate information exchange 

about all types of engineering tool applications examples. Comparison studies such as the one 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

performed by Lord et al. [16] on evacuation models would be welcome, rather based on study 

topics selected in the first phase of the 'test bed' studies than on a generic parametric analysis. 

This idea is linked to how the validation domain of the tools from research laboratory 

experiments could be extended in order to include all the diverse real life complex multi-story 

facilities which are the subject of PBFPD applications. The current process tends to involve a 

simultaneous and quite independent increase of the experimental input data ranges to correspond 

to real engineering projects. It is thought that (a) establishing a list of non-dimensional 

parameters which characterize related phenomena [17] and (b) describing the engineering 

projects with these parameters, would may cluster the application domain and this way lead to 

specific research to ultimately include these application clusters in the validation domain of the 

tools. McGrattan [17] stated that "the burden of [verification and validation] V&V must be 

shared by the model developer and the user". In this matter, the 'test bed' environment is then 

designed to increase the collaboration between tool developers and users. 

In parallel to collecting building layouts, a set of „combustible packages‟ representing 3-D 

objects such as chairs, couches, and beds, which contain heat release rate, chemical reaction, and 

toxicity properties needed for the simulations, has been developed. The benefits of such data are 

that scenarios describe burning elements in the same way so that the focus of the „test bed‟ 

studies remains the use of the tools for fire consequence analysis. A separate study, using 

different „combustible packages‟ in FDS, shows that the same fuel item can be described 

differently whether the fire consequence analysis concerns the near field of the spreading fire or 

the far field. This study purpose is then to help the users of fire effects tools when characterizing 

the degree of details necessary to describe the design fire curves for a particular design fire 

scenario [18]. 

The third phase is dedicated to the analysis of the provided results by all participants of the 

previous phase and by the stakeholders who helped defined the safety objectives. This phase is 

aimed to provide the guidelines for selection of tools for a given application. 

Benefits of conducting such „test bed‟ studies are as diverse as the different participants to the 

studies [5]. Such guidelines related to the use of tools for PBFPD applications would be 

beneficial not only to consulting companies, engineering societies, regulators and AHJ, but also 

students and professors in Academia and governmental agencies which could set up research 

programs focusing on the problems and needs of the fire engineering community. 

ACKNOWLEDGEMENT 

This research is supported by NIST award 60NANB10D228. 

REFERENCES 

1.	 SFPE, Guidelines for Substantiating a Fire Model for a Given Application, 2011 

2.	 SFPE, SFPE Engineering Guide to Performance-Based Fire Protection, 2007 

3.	 SFPE/ICC, Code Official's Guide to Performance-Based Design Review (chapter 11), 

Society of Fire Protection Engineers and International Code Council, 2004 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.	 NRC-EPRI, Verification and Validation of Selected Fire Models for Nuclear Power Plant 

Applications, vol. 1-7 (NUREG-1824 and EPRI 1011999, 2007) 

5.	 Alvarez, A. and Meacham, B. J., ""Ready-to-use" Building Layouts and Combustible 

Packages for 3-D simulations", proceedings of the Fire and Evacuation Modeling Technical 

Conference, 2011 

6.	 Friedman, R., "An International Survey of Computer Models for Fire and Smoke," Journal of 

Fire Protection Engineer, 4 (3), 1992, pp 81-92 

7.	 Mowrer, F.W. (2002),"The Right Tool for the Job," Fire Protection Engineering Magazine 

(SFPE), Vol. 13, Winter, 2002, pp. 39–45 

8.	 (ABCB) Australian Building Codes Board (2005), International Fire Engineering Guidelines, 

2005 

9.	 Proulx, G., Reid, I. and Cavan, N.R., Human Behavior Study, Cook County Administration 

Building Fire, October 17, 2003 Chicago, IL, Research Report No. 181, April 2004 

10. Chu, G.Q., Chen, T., Sun, Z.H. and Sun, J.H., "Probabilistic risk assessment for evacuees in 

building fires," Building and Environment 42, 2007, pp. 1283–1290 

11. NFPA 204: standard for Smoke and Heat Venting, National Fire Protection Association, 

2012 

12. NFPA 92: standard for Smoke Control Systems, National Fire Protection Association, 2012 

13. Floyd, J.,	 “Coupling a Network HVAC Model to a Computational Fluid Dynamics Model 

Using Large Eddy Simulation,” Proceedings of the Tenth International Symposium of 

IAFSS, International Association for Fire Safety Science, 2011 

14. SFPE, proceedings of the 8th International conferences on performance-based codes and fire 

safety design methods, Society of Fire Protection Engineers (2010) 

15. Pin, Yat Fat and Wu, Kwun Hing, "Fire Modeling with CAD/GE1 Techniques," proceedings 

of the Fire and Evacuation Modeling Technical Conference, 2011 

16. Lord, J., Meacham, B., Moore, A., Fahy, R. and Proulx, G, "Guide for Evaluating the 

Predictive Capabilities of Computer Egress Models", National Institute of Standards and 

Technology, NIST GCR 06-886, 2005 

17. McGrattan, K. and Myers, T., "A Way to Characterize the Range of Validity of a Fire Model, 

proceedings of the Fire and Evacuation Modeling Technical Conference, 2011 

18. Alvarez, A., Dembsey, N. A. and Meacham, B. J., "Combustible packages for 3D simulations 

using FDS – Simulating experiments in the FDS Chamber", manuscript to be submitted for 

publication in June 2012 
 

Annex B 

Comparison of the International Fire Engineering Guidelines, SFPE 

Engineering Guide on Performance-Based Fire Protection, BS7974 – 

Application of Fire Safety Engineering Principles to the Design of Buildings 

and ISO 13387 - Fire Safety Engineering – Part 1: Application of Fire 

Performance Concepts to Design Objectives 
 

A High-Level Comparison of the International Fire Engineering Guidelines, 

BS 7974 - Application of Fire Safety Engineering Principles to the Design of
 

Buildings, SFPE Engineering Guide to Performance-Based Fire Protection,
 

ISO 13387 - Application of Fire Performance Concepts to Design Objectives
 

Prepared by 

Valerie Boutin
 

Brian Meacham
 

Date 

February 2013 

Department of Fire Protection Engineering 

Worcester Polytechnic Institute 

Worcester, MA 01609 USA 

http://www.wpi.edu/academics/fpe.html 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

NOTICE 

This report was prepared by Valerie Boutin and Brian Meacham as part of a research effort supported by the National Institute 

of Standards and Technology (NIST) Award 60NANB10D228 into characterization of risk, design fires, design fire scenarios and 

criteria as embodied in current fire safety engineering design guidance. Information presented in this report was obtained 

through a high-level review of the International Fire Engineering Guidelines, BS 7974, Application of Fire Safety Engineering 

principles to the Design of Buildings, the SFPE Engineering Guide to Performance-Based Fire Protection, ISO 13387, Application 

of Fire Performance Concepts to Design Objectives, and the comparison of BS7974 and the International Fire Engineering 

Guidelines conducted by Ove Arup & Partners for the Scottish government in 2006. Reasonable attempts were made to verify 

the accuracy of the information provided, referenced and summarized in this report. However, neither the authors, nor 

Worcester Polytechnic Institute, nor any person acting on their behalf: 

a. Makes any warranty, express or implied, with respect to the use of any information, apparatus, method or process 

disclosed in this report, or that such use may not infringe upon privately owned rights; or 

b. Assumes any liabilities of whatsoever kind with respect to the use of, or damage resulting from use of, any 

information, apparatus, method or process disclosed in this report. 

Any summaries, opinions, findings, conclusions or recommendations expressed in this report are those of the authors and do 

not necessarily reflect project sponsors, institutions, agencies or organizations. 

2
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

EXECUTIVE SUMMARY 

This report provides a ‘high-level’ comparison of the International Fire Engineering Guidelines (IFEG) with BS 7974, 

Application of Fire Safety Engineering Principles to the Design of Buildings, the SFPE Engineering Guide to 

Performance-Based Fire Protection, and ISO 13387, Application of Fire Performance Concepts to Design Objectives. 

This comparison was supported by the National Institute of Standards and Technology (NIST) under Award 

60NANB10D228 to WPI for research into various aspects of performance-based fire engineering design guidance 

and regulatory needs. The presentation of material in this report was formatted specifically to assist the IFEG 

Editorial Committee benchmark the relevancy of the IFEG relative to current fire safety engineering practice and 

informing possible updates or changes to the IFEG following the format a 2006 report which compared the IFEG to 

BS7974 for the Scottish government. 

The comparison is provided in two parts: (1) a comparative summary of the structures of the four engineering 

guidance documents, and (2) a more detailed comparison of the specific information, data and methodologies 

provided in each document. While each of the documents reviewed includes references to other sources of 

information, these references were not reviewed as part of this effort. Likewise, no commentary is provided 

relative to the appropriateness or efficacy of the data and methods provided in the documents. 

Based on this comparison, it is concluded that the International Fire Engineering Guidelines (IFEG) is contemporary 

in scope, process, and general methodologies used with BS 7974, Application of Fire Safety Engineering Principles 

to the Design of Buildings, the SFPE Engineering Guide to Performance-Based Fire Protection, and ISO 13387, 

Application of Fire Performance Concepts to Design Objectives. The general framework of all four approaches is 

effectively the same – a result of a high degree of overlap amongst developers of each. In addition, the 

methodologies used and evaluation methods recommended are largely the same. This is a function of the state of 

the art when the guides were developed (all prior to 2005) and the commonality of reference sources across the 

fire engineering community. Likewise, documentation requirements are largely the same. 

In general, BS 7974 includes more detailed methods of evaluation than IFEG, ISO 13387 and the SFPE Guide, as 

these documents refer to other sources (IFEG has more than the other two). Each refers often to the SFPE 

Handbook of Fire Protection Engineering as well as to relevant standards. It is also worth noting that ISO has 

numerous ‘sub-standards’ – which link directly to ISO 13387 – that include much more detailed methodologies 

across all areas (fire, smoke, detection, etc.). While this makes the ISO ‘suite’ the most comprehensive, it may be 

considered by some cost-prohibitive from a practitioner perspective. (The ISO ‘sub-standards’ were not reviewed.) 

One area lacking in the IFEG, ISO and SFPE Guide, as compared with BS 7974, is risk assessment and probabilistic 

methods. While IFEG, ISO and SFPE Guide all include some guidance, they largely refer out to other documents. 

SFPE has a guide on fire risk assessment, and ISO has a standard on fire risk assessment, for example, while BS 

7974 includes probabilistic risk assessment as Part 7 of the package. While it was decided not to include guidelines 

currently under development (e.g., Nordic, European and others), the probabilistic approach is one area which 

these new documents are including. 

3
 
 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

EXECUTIVE SUMMARY 

This report provides a ‘high-level’ comparison of the International Fire Engineering Guidelines (IFEG) with BS 7974, 

Application of Fire Safety Engineering principles to the Design of Buildings, the SFPE Engineering Guide to 

Performance-Based Fire Protection, and ISO 13387, Application of Fire Performance Concepts to Design Objectives, 

for the purpose of helping the IFEG Editorial Committee benchmark the relevancy of the IFEG relative to current 

fire safety engineering practice and informing possible updates or changes to the IFEG. 

The review is provided in two parts: a comparative summary of the structures of the four engineering guidance 

documents, and a more detailed comparison of the information, data and methodologies provided in each 

document. While each of the documents reviewed includes references to other sources of information, these 

references were not reviewed as part of this effort. Likewise, no commentary is provided relative to the 

appropriateness or efficacy of the data and methods provided in the documents. 

Based on this review, it is concluded that the International Fire Engineering Guidelines (IFEG) is contemporary in 

scope, process, and general methodologies used with BS 7974, Application of Fire Safety Engineering principles to 

the Design of Buildings, the SFPE Engineering Guide to Performance-Based Fire Protection, and ISO 13387, 

Application of Fire Performance Concepts to Design Objectives. The general framework of all four approaches is 

effectively the same – a result of a high degree of overlap amongst developers of each. In addition, the 

methodologies used and evaluation methods recommended are largely the same. This is a function of the state of 

the art when the guides were developed (all prior to 2005) and the commonality of reference sources across the 

fire engineering community. Likewise, documentation requirements are largely the same. 

In general, BS 7974 includes more detailed methods of evaluation than IFEG, ISO 13387 and the SFPE Guide, as 

these documents refer to other sources (IFEG has more than the other two). Each refers often to the SFPE 

Handbook of Fire Protection Engineering as well as to relevant standards. It is also worth noting that ISO has 

numerous ‘sub-standards’ – by which I mean standards that link to ISO 13387 – which include much more detailed 

methodologies across all areas (fire, smoke, detection, etc.). While this makes the ISO ‘suite’ the most 

comprehensive, it may be considered by some cost-prohibitive. 

One area lacking in the IFEG, ISO and SFPE Guide, as compared with BS 7974, is risk assessment and probabilistic 

methods. While IFEG, ISO and SFPE Guide all include some guidance, they largely refer out to other documents. 

SFPE has a guide on fire risk assessment, and ISO has a standard on fire risk assessment, for example, while BS 

7974 includes probabilistic risk assessment as Part 7 of the package. While it was decided not to include guidelines 

currently under development (e.g., Nordic, European and others), the probabilistic approach is one area which 

these new documents are including. 

3 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

CONTENTS 

Executive Summary .......................................................................................................................................................3
 

Background and Introduction........................................................................................................................................5
 

SCOPE, Structure and Application .................................................................................................................................8
 

BS7974.......................................................................................................................................................................8
 

IFEG1 

..........................................................................................................................................................................9
 

SFPE Guide ................................................................................................................................................................9
 

ISO TR 13387-1 ........................................................................................................................................................11
 

Overall Process and Major Components .....................................................................................................................13
 

BS7974.....................................................................................................................................................................13
 

IFEG .........................................................................................................................................................................13
 

SFPE Guide ..............................................................................................................................................................15
 

ISO TR 13387-1 ........................................................................................................................................................18
 

Methods of Evaluation ................................................................................................................................................20
 

BS7974.....................................................................................................................................................................20
 

IFEG .........................................................................................................................................................................20
 

SFPE Guide ..............................................................................................................................................................22
 

ISO TR 13387-1 ........................................................................................................................................................25
 

Variability & Uncertainty .............................................................................................................................................26
 

BS7974.....................................................................................................................................................................26
 

IFEG .........................................................................................................................................................................26
 

SFPE Guide ..............................................................................................................................................................26
 

ISO TR 13387-1 ........................................................................................................................................................27
 

Documentation............................................................................................................................................................28
 

BS7974.....................................................................................................................................................................28
 

IFEG .........................................................................................................................................................................28
 

SFPE Guide ..............................................................................................................................................................29
 

ISO TR 13387-1 ........................................................................................................................................................30
 

Summary......................................................................................................................................................................31
 

Detailed Comparison Tables........................................................................................................................................32
 

4 
 

 

 

 

 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974	 Summary Report 

BACKGROUND AND INTRODUCTION 

In 2010, the Editorial Committee (EC) for the International Fire Engineering Guidelines (IFEG) began its required 5-

year review of the IFEG to determine if it remained a contemporary document, fit for the purpose of providing 

guidance to fire safety engineers. This involved various surveys of fire engineers in EC member countries and of 

IRCC members. After the initial set of surveys, an EC meeting was held in Worcester, Massachusetts, USA, in 

October 2010. 

At the October 2010 meeting, the EC agreed that the IFEG was a contemporary document and fit for purpose. 

However, the EC agreed that the IFEG should be compared with other contemporary fire engineering process 

documents in order to identify a potential scope for ongoing development. Brian Meacham, associate professor of 

fire protection engineering at Worcester Polytechnic Institute (WPI), offered to undertake a review of the IFEG in 

comparison to the SFPE Guide on Performance-Based Fire Protection and ISO 13387, Application of Fire 

Performance Concepts to Design Objectives, following the format of the comparison of the IFEG to BS 7974, 

Application of Fire Safety Engineering principles to the Design of Buildings, undertaken by Ove Arup & Partners for 

the Scottish government in 2006. The target for the completion of the review was December 2012. 

A subsequent meeting was held in March 2011 between Brian Meacham, Brian Ashe and Ray Loveridge to further 

discuss the outcomes of the Boston meeting and the scope of the comparative analysis. Key issues on the scope 

related to whether regulatory documents, such as the New Zealand Verification Method for Fire, which was 

significantly modified to include details on scenarios, design fire quantification, verification methods and criteria, 

and the new Swedish building regulations, which include similar components as well as a risk-based approach, 

should be considered. If was furthermore suggested that additional feedback from IRCC members and 

practitioners would be helpful. With respect to the IRCC, key questions included what value the IFEG is to them 

and what changes they might desire if they were to use them. This was asked in the light of whether the ABCB 

would like to have responsibility, in the future, for the IFEG. This was discussed at the May 2011 IRCC meeting in 

Bergen, Norway, where IRCC members offered the following comments: 

•	 Norway: fire engineering is part of most building designs. In most cases where the design is deviating from the 

Approved Document, a comparative analysis that may include deterministic and/or probabilistic analyzing 

methods is performed. British Standard AS7974:2001 'Application of fire safety engineering principles to the 

design of buildings. Code of Practice' is used when required. Standards Norway is intending to publish a 

revised version of the Norwegian standard NS 3901 Requirements to risk assessment for fire in construction 

works. 

•	 Scotland: fire engineering of building designs is not common practice and British Standard AS7974:2001 is 

used when required. 

•	 Austria: fire engineering of building designs is supported. However; German guidelines are adopted. Most 

practitioners would not speak English; therefore adoption of the IFEG would be impractical. 

•	 Singapore: has no 'preferred' guidelines for use by practitioners and is keen to participate in the further 

development of the IFEG. Singapore sought more information on New Zealand's proposed reforms and 

questioned the expected scope of their contribution to development of the IFEG. 

•	 New Zealand: supported further development of the IFEG. 

•	 Canada: considered that Singapore's contribution could initially comprise development of a Singaporean ‘Part 

0’ for inclusion in the IFEG and proposed that Singapore should collaborate with the Editorial Committee on 

future development of the IFEG. 

•	 Australia: advised members that the ABCB did not intend to independently review the IFEG. 

5 
 

 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974	 Summary Report 

Following the Bergen IRCC meeting, a decision was taken to obtain additional feedback from industry. In 

September 2011, at the ABCB Conference on Building Australia’s Future, the EC received input from the Australian 

Society of Fire Safety (SFS), a 'practitioner' Society within the Institute of Engineers Australia, and the Australasian 

Fire and Emergency Services Authorities Council, a jurisdictional Fire Brigade group. Feedback from these groups 

indicated that while some significant changes would be welcome, these groups did not step up to help. The EC 

then questioned whether they should be responsible for promoting change, or whether change should be driven 

by industry. This question was posed to the IRCC. Response from IRCC members is as follows: 

•	 Industry practitioners should become a champion of future reform of the IFEG. 

•	 Restructuring the IFEG would not in itself be sufficient reform to augment current international 

application. 

•	 International perspectives suggest the IFEG should remain a process document. An Australian perspective 

(SFS) suggests that the content should be updated and expanded to incorporate a relevant database. 

•	 There would be benefit in exploring the merits of facilitating a consistent approach between the IFEG and 

the revised New Zealand approach. 

In light of IRCC member response to the survey, it was evident there is limited international interest in reviewing 

the IFEG. Therefore the decision was taken that ABCB should retain responsibility for the document and the 

existing EC should retain its editorial role. It was also decided that the EC should delay further review of the IFEG 

pending receipt of outcomes of the international comparative analysis, and that further review activities should be 

undertaken in collaboration with relevant stakeholders. 

This document reflects the international comparison referred to above. The scope, as ultimately decided, is limited 

to a comparison of process and methodology embodied within the IFEG with those embodied within BS 7974, 

Application of Fire Safety Engineering principles to the Design of Buildings, the SFPE Engineering Guide to 

Performance-Based Fire Protection, and ISO 13387, Application of Fire Performance Concepts to Design Objectives. 

The review is provided in two parts: a comparative summary of the structures of the four engineering guidance 

documents, and a more detailed comparison of the information, data and methodologies provided in each 

document. While each of the documents reviewed includes references to other sources of information, these 

references were not reviewed as part of this effort. Likewise, no commentary is provided relative to the 

appropriateness or efficacy of the data and methods provided in the documents. 

Unless otherwise noted, discussion regarding comparison between BS7974 and the International Fire Engineering 

Guidelines (IFEG) comes from the review conducted by Over Arup and Partners for the Scottish government 

(report can be found at http://www.scotland.gov.uk/Resource/Doc/217736/0090824.pdf). Discussion on the SFPE 

Engineering Guide to Performance-Based Fire Protection and ISO 13387, Application of Fire Performance Concepts 

to Design Objectives, has been developed by the authors, drawing from the source documents as appropriate. 

Based on decisions as outlined above, no consideration is given to current regulatory approaches, or to new 

guidance under development, such as the Nordic Fire Engineering Guidelines, the new SFPE standards committee 

on design fire scenarios and fires, or continued development of ISO documents in support of TR 13387. To the 

latter point, both SFPE and ISO have a range of reference documents, to which their ‘process’ guidelines point, 

which were not then included in this comparison. For this reason, it should not be concluded that ISO and SFPE do 

not address several issues, but only that their process documents do not. 

6 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

This section of the report, then, provides a narrative summary of the scope, structure, process, and methodologies 

identified within the considered documents, including recommended processes developing, evaluating and 

documenting designs. The second part of the review provides, in tabular form, a comparison of how each of the 

considered documents addresses components of the overall fire safety engineering process, including specific 

methodologies and data that may be incorporated or referenced. While reasonable attempts have been made to 

include all aspects, it is possible that some errors or omissions exist, and this comparison should be considered 

appropriately. 

7 
 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974	 Summary Report 

SCOPE, STRUCTURE AND APPLICATION 

This section overviews the general scope, structure and application of the reviewed documents. In general, all four 

documents provide a framework for engineering analysis, which has flexibility to fit individual project needs, apply 

to new or existing construction, and require evaluation of design alternatives against criteria established by the 

engineering team. Each document identifies a set of fire safety ‘systems’ for which design solutions may be 

engineered. 

BS7974
 

BS7974 is in effect a ‘framework’ code of practice under which sits a set of Published Documents [PD’s]. This study 

embraces the PD’s along with the BS 7974. The BS code of practice “provides a framework for developing a rational 

methodology for design of buildings using a fire safety engineering approach based on the application of scientific 

and engineering principles to the protection of people, property and the environment from fire”. 

It may be applied to new or existing buildings, to show that regulatory requirements can be met. It is intended to 

be applied to three main stages: 

1.	 Qualitative Design Review [QDR]: in which the scope and objectives of the fire safety design are defined, 

performance criteria established and one or more potential design solutions proposed. 

2.	 Quantitative Analysis: engineering methods are used to evaluate the potential solutions identified in the 

QDR. 

3.	 Assessment Against Criteria: the output of the quantitative analysis is compared to the acceptance criteria 

identified in the QDR. 

The BS7974 provides guidance on these procedures. The sub-systems in the PD’s provide data and analytical 

methods for tackling the relevant quantitative analysis, and advice on acceptance criteria and suitable design 

approaches. The document structure with the sub-systems is illustrated in Figure 1. 

BS7974 Code of PracticeApplication of fire safety engineering principles to the design of buildings 

BSPD7974- BSPD7974-

1 

BSPD7974-

2 

BSPD7974-

3 

BSPD7974 

- 4 

BSPD7974-

5 

BSPD7974-

6 

BSPD7974-

0 7 

Guide to Initiation and 

development 

of fire within 

enclosure of 

origin 

Spread of 

smoke and 

toxic gases 

within and 

beyond the 

enclosure of 

origin 

Structural 

response 

and fire 

spread 

beyond the 

enclosure 

of origin 

Detection 

of fire and 

activation 

of fire 

protection 

systems 

Fire service 

intervention 

Evacuation Probabilistic 

design risk 

framework assessment 

and fire 

safety 

engineering 

procedures 

Figure 1: Structure of sub-systems in BS7974 

Note that 0 and 7 are not sub-systems as such, i.e., they do not address characteristics of fire or safety systems. 

PD0 provides guidance on procedure and PD7 provides guidance on risk assessment techniques, both being 

applicable to any of the other subsystem. 

8 
 

 

 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

IFEG1 

The guidelines document and approach uses a very similar sub-systems break-down of the subject to that used in 

BS7974. The guidelines are derived from an earlier Australian document (the draft National Building Fire Safety 

Systems code). In the early 1990’s the original consultant team commissioned to draft the document that 

eventually became BS7974 in the UK, were in contact with members of the team who were working on the first 

edition of the Australian Fire Engineering Safety Systems code at the same time. There was cross-fertilization 

between these groups. 

The UK group picked up the Australian sub-system concept and the Australian group adopted the UK QDR concept 

(though some of the terminology was altered). The structure of the IFEG after the ‘national’ introductory sections 

is in three parts: 

1. Process 

2. Methodologies 

3. Data 

The sub-system approach is introduced in section 1.3.1 of the IFEG document. As noted the IFEG sub-systems bear 

a very close resemblance to those used in BS7974. They are set out in Figure 2 below. The following quote from 

IFEG 1.3.2 is important in that it qualifies the importance of the whole sub-system principle: 

“Typically, each building project is unique and similarly, each fire engineering evaluation is unique. It is not 

sensible, therefore, to set down detailed guidance on how the fire safety analysis should be undertaken. 

Instead, it is the responsibility of the fire engineer to plan the analysis for the particular project, based on the 

decisions taken during the preparation of the FEB as discussed in Chapter 1.2.” 

Subsystem A Subsystem B Subsystem C Subsystem D Subsystem E Subsystem F 

Fire initiation 

and 

development 

and control of 

fire within 

enclosure of 

origin as well as 

enclosures to 

which fire 

subsequently 

spreads 

Development 

and spread of 

smoke within 

the building, and 

its control 

Spread of fire 

beyond the 

enclosure of 

origin, impact on 

structure and 

how spread and 

impact may be 

controlled 

Fire detection 

warning and 

suppression. 

Enables 

suppression 

effectiveness to 

be estimated 

Occupant 

evacuation and 

control. Enables 

estimate of time 

to reach place of 

safety 

Fire services 

intervention. 

Effectiveness of 

intervention 

including 

suppression. 

Figure 2: The IFEG sub-systems 

SFPE GUIDE
 

The SFPE Guide is also a ‘framework’ document. It identifies a number of steps which should be undertaken in 

identifying relevant fire safety goals for a project, developing quantified design criteria against which to evaluate 

fire safety performance, developing fire scenarios and quantified design fires for use in the evaluation, and 

selection and evaluation of fire protection options. 

9 
 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

This SFPE Guide is applicable to new or existing projects. It overviews the basic building design process (Figure 3), 

indicating that the fire analysis and design approach can fit into the overall design process at any stage, and 

identifies what type of information or analysis may be needed at each step. 

Conceptual Design 

(Se Figure 3-2) 

Feasibility Study 

Schematic Design 

Design Development 

Design Documentation 

Construction/Installation 

Commissioning 

Certificate of Occupancy 

Use and Maintenance Change in Use/ 

Refurbishment 

Figure 3: Basic Building Process 

The SFPE Guide defines four levels of application which can be undertaken: 

1) The performance-based design process can be used to evaluate and recommend fire protection options at 

the subsystem performance level, at the system performance level, or at the building performance level. 

At any level, the results could be evaluated on a comparative or absolute basis. 

2) A subsystem performance evaluation typically consists of a simple comparative analysis in which it is 

required to demonstrate that a selected subsystem provides “equivalent” performance to that specified 

by a prescriptive based code. At this level, one subsystem is evaluated in isolation. 

3) A system performance evaluation could consist of a comparative or absolute analysis. A system 

performance evaluation is used when more than one fire protection system or feature is involved. A 

system performance evaluation is more complex than a subsystem evaluation, as the analysis needs to 

take account of the interaction between various subsystems. 

10 
 

Comparison of IFEG, ISO, SFPE and BS7974	 Summary Report 

4)	 In a building performance analysis, all subsystems used in the protection strategy and their interactions 

are considered. A performance-based design that takes into account total building fire safety can provide 

more comprehensive solutions than subsystem or subsystem performance analyses, because the entire 

building-fire-target interaction is evaluated. 

Much like BS7974 and the IFEG, the SFPE Guide identifies six subsystems for which fire protection strategies can be 

developed: 

1) Fire Initiation and Development (Section 9.2)
 

2) Spread, Control, and Management of Smoke (Section 9.3)
 

3) Fire Detection and Notification (Section 9.4)
 

4) Fire Suppression (Section 9.5)
 

5) Egress Provisions Including Occupant Behavior (Section 9.6)
 

6) Passive Fire Protection (Section 9.7)
 

The SFPE Guide outlines a series of steps for project documentation: the Fire Protection Engineering Design Brief, 

the Fire Protection Design Report, and an Operations and Maintenance Manual. The SFPE Guide informs users to 

carefully identify and document assumptions, limitations and bounding conditions relevant to any recommended 

design. Just as there was cross fertilization between the IFEG and BS7974 developers, the developers of the SFPE 

Guide were familiar with the concepts and approaches underpinning the IFEG, BS7974 and ISO TR 13387. 

ISO TR 13387-1
 

ISO TR 13387-1 is similar to BS7974 in that it is a document which describes a framework for the provision of an 

engineered approach to the achievement of fire safety in buildings, based on the quantification of the behavior of 

fire and people. ISO TR 13387-1, coupled with the other ISO documents which provide more detailed aspects of 

fire safety design, can be applied to any type of new or existing building. 

Much like BS7974, ISO TR 13387-1 is intended to be applied to three main stages: 

1.	 Qualitative Design Review [QDR]: The review is qualitative because not all the values of the design 

parameters will be known and engineering judgment will need to be applied to obtain them. It is also 

qualitative because judgment will need to be used to decide on a limited number of important fire 

scenarios for later quantified analysis; 

2.	 Quantitative Analysis: engineering methods are used to carry out a time-based quantified analysis using 

the appropriate subsystems — or use another appropriate method of analysis as indicated in the QDR, 

making sure that, wherever possible, mathematical models are verified; 

3.	 Assessment against Criteria: the output of the quantitative analysis is compared to the acceptance criteria 

identified in the QDR. 

4.	 Reporting Results: Documentation of the analyses. 

Similar to the BS7974 and the IFEG, the ISO is divided into sub-systems. There are five sub-systems in total: 

1) Initiation and development of fire and generation of fire effluents (ISO 13387-4)
 

2) Movement of fire effluents (ISO 13387-5)
 

3) Structural response and fire spread beyond the enclosure of origin (ISO 13387-6)
 

4) Detection, activation and suppression (ISO 13387-7)
 

5) Life safety: occupant behavior, location and condition (ISO 13387-8)
 

11 
 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

The subsystems interact as in the illustration below (Figure 4): 

Figure 4: The global information framework as described in ISO TR 13387-1
 

12
 
 

 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

OVERALL PROCESS AND MAJOR COMPONENTS 

This section provides an overview of the fire engineering process and the major components which are considered. 

BS7974
 

As noted above, BS7974 is intended to be applied to three main stages, Qualitative Design Review, Quantitative 

Analysis and Assessment against Criteria, as outlined in Figure 5. 

Qualitative 

Design 

Review 

Quantitative 

Analysis 

Assessment 

Against 

Criteria 

Figure 5: The engineering approach described in BS7974 

In the Qualitative Design Review (QDR), the scope and objectives of the fire safety design are defined, performance 

criteria are established and one or more potential design solutions proposed. Engineering methods are then used 

to evaluate the potential solutions during the quantitative review. The output of the quantitative analysis is 

compared to the acceptance criteria identified in the QDR. The QDR is roughly equivalent to the Fire Engineering 

Brief (FEB) in the IFEG and Fire Protection Engineering Design Brief (FPEDB) in the SFPE Guide. 

IFEG
 

The “Process” section of the IFEG offers guidance on what issues should be addressed in the Fire Engineering Brief 

[FEB]. The FEB is a process as well as a document. It defines the scope of the fire engineering analysis, and the 

basis on which that analysis will be undertaken. All interested parties including the Authority Having Jurisdiction 

[AHJ], have to be involved, since key components of the FEB include acceptance criteria. These criteria are likely to 

be more detailed than the Functional Standards of building regulations. 

The process outlined in the IFEG is as follows: 

Figure 6: Sequence of the fire engineering process in the IFEG 

The IFEG gives an illustration [Figure 7 see below] of a process for developing a FEB. The IFEG notes that the FEB 

may vary based on the requirements of a project. The steps shown in Figure 7 may be re-ordered, omitted or an 

iterative process introduced. The first stage in the Guidelines is the preparation a Fire Engineering Brief (FEB). A 

practical criticism of the FEB principle identified in the Arup report is that it is generally impossible to follow in a 

real project since there are many unknowns in the early stages. The IFEG acknowledges this, noting that there are 

many unknowns in the early stages, and noting that there may well be iterative loops in its development and in 

accepting that there may be preliminary “test” calculations/analyses to establish the likelihood of success before 

trial designs are defined ready for fuller analysis. Typically there may be some exploratory ‘hand calculations’ 

before the fire engineer advises the design team to take a particular approach, after which a more time-consuming 

analysis may be carried out to test the approach, once the design has been further developed. The FEB is not 

Prepare FEB Carry Out 

Analysis
 

Collate and 

Evaluate 

Results
 

Draw 

Conclusions
 

Prepare 

Report
 

13 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

necessarily fixed [1.2.14]: “Sometimes, as the analysis of a design proceeds or as a project develops, it may be 

appropriate to revise the FEB, adopting the same consultative approach as with the original. The ‘final’ FEB will be 

incorporated into the overall report” 

Scope of Project 

1.2.1 

Relevant Stakeholders 

1.2.2 

Prinipal Building Characteristics 

1.2.3 

Dominent Occupant Characteristics 

1.2.4 

General Objectives 

1.2.5 

Hazards and Preventative and
 

Protective Measures Available
 

1.2.6 

Trial Designs for Assessment 

1.2.7 

Non-complience issues and
 

Specific Objective or Performance Requirements
 

1.2.8
 

Approaches and Methods of Analysis 

1.2.9 

Acceptance Criteria and Factors 

of Safety for the Analysis 

1.2.10 

Fire Scenarios & Parameters for Design Fires 

1.2.11 

Parameter for Design Occupant Groups 

1.2.12 

Standards of Construction, Commissioning, 

Management, Use and Maintenance 

1.2.13 

The FEB Report 

1.2.14 

Figure 7: Process for developing a FEB 

14 
 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

SFPE GUIDE
 

The SFPE Engineering Guide describes the process for performance based design and analysis process as illustrated 

in Figure 8 below. 

Define Project Scope 

(Chapter 4) 

Identify Goals 

(Chapter 5) Design Brief 

(Chapter 11) 

Define Stakeholder 

and Design Objectives 

(Chapter 6) 

Develop Performance
 

Criteria (Chapter 7)
 

Develop Design Fire
 

Scenarios (Chapter 8)
 

Develop Trial Designs 

(Chapter 9) 

Evaluate Trial Designs 

(Chapter 10) 

(see Figure 10-2) 

Yes 

Select the Final Design 

(see Figure 10-2) 

Prepare Design 

Documentation 

Selected Design 

Meets Performance 

Criteria? 

No 

Objectives 

(see Figure 10-2) 

Modify Design or 

Specifications, Drawings, and 

Operations and Maintenance 

Manual (Chapter 12) 

Performance-Based 

Design Report 

(Chapter 12) 

Figure 8: Performance based design and analysis procedure 

The first step in the SFPE process is to develop the Fire Protection Engineering Design Brief which consists of 6 

major components: 

1. Define Project Scope 

2. Identify Goals 

3. Define Stake holder and Design Objectives 

15 
 

 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

4. Develop Performance Criteria 

5. Develop Design Fire Scenarios 

6. Develop Trial Designs 

Each of these subsections is discussed in its own chapter. The component is defined and all the necessary parts 

are highlighted. The majority of the time, examples are provided. 

For setting goals and objectives, discussion is provided in the main body of the Guide, with examples provided in 

the appendices. Unlike BS7974, specific criteria are not suggested, with references provided to engineers to seek 

criteria and values as appropriate to their project and approach (e.g., deterministic or probabilistic). 

Several illustrations are provided to aid in the development of fire scenarios (Figure 9) and trial designs (Figure 10 

and Figure 11). 

Identify Fire Scenarios 

Manage Fire 

+ 

Evaluate Trial 

Designs 

(See Chapter 10) 

Possible Fire 

Scenarios 

Fire 

Characteristics 

Building 

Characteristics 

Occupant 

Characteristics 

Design 

Fire Scenarios 

Design Fire 

Curves 

Building 

Characteristics 

Occupant 

Characteristics 

Develop 

Candidate 

Designs 

(See Chapter 9) 

Figure 9: Development of fire scenarios 

Control 

combustion 

process 

Control fire by 

construction Suppress fire 

Figure 3: Top Level of the Firesafety Concepts Tree 

16 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

Figure 4: Limiting the spread of fire 

17
 

Manage fire 

Control fuel 

Control combustion 

process 

Control the 

environment 

Control fuel 

properties 

Limit fuel 

quantity distribution

Control fuel 

physical 

Control 

environment properites of 

Control 

chemical 

composition of 

environment 

Control fire by construction 

Provide structural 

stability 

Control movement 

of fire 

Vent fire Confine/ 

contain fire 

+ 

+ 

+ + + 

Suppress fire 

Automatically suppress fire 

+

Apply Detect fire 

sufficient 

suppressant 

Manualy suppress fire 

Communicate 

signal 

Decide action Respond to 

site 

Detect fire Apply 

sufficient 

suppressant 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

ISO TR 13387-1
 

As noted above, the ISO standard defines four main steps in the overall process: 

1. Qualitative design review (QDR) 

2. Quantitative analysis of design 

3. Assess the outcome of the analysis against the safety criteria 

4. Report and present the results 

The steps are discussed in greater detail in the ISO 13387-1 document. The figure below gives a visual 

representation of the steps. 

Figure 5: ISO basic fire safety design process 

18 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

A major step in the QDR is the identification of design fire scenarios. The components of a design fire scenario are: 

• Type of fire 

• Internal ventilation conditions 

• External environmental conditions 

• Performance of each of the fire safety measures 

• Type, size, and location of ignition source 

• Distribution and type of fuel 

• Fire load density 

• Fire suppression 

• State of doors 

• Breakage of windows 

• Building air-handling system 

Examples of typical design fire scenarios are provided. There are a total of 10 steps in creating a design fire 

scenario: 

1) Type of fire 

2) Location of fire 

3) Potential fire hazards 

4) Systems impacting on fire 

5) Occupant response 

6) Event tree 

7) Consideration of probability 

8) Consideration of consequences 

9) Risk ranking 

10) Final selection and documentation 

The steps to the design fire scenario are explained in more detail in ISO 13387-2. 

19 
 

 

 

3

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

This section overviews how the various documents address methods of evaluation which may be used. 

METHODS OF EVALUATION 

Trial Design 

1.2.7 1 Determine Specific Objectives or 

Performance Requiremetns 

1.2.8.2 

Determine Non Compliance Issues 

1.2.8.1 2 

Select Approaches and 

Methods of Analysis 

1.2.9 4 

Absolute Approach 

1.2.9.1 4a 

Quantitative Approach 

1.2.9.2 4b 

Qualitative Approach 

1.2.9.2 4b 

Probabilistic Approach 

1.2.9.3 4c 

Or 

Or 

Or 

BS7974
 

The evaluation approached are discussed in the various subsystem (PD) documents (e.g., BSPD7974 1 through 7), 

which describe different areas of fire safety engineering and methods of evaluation in some in detail. The PD 

documents were not reviewed as part of this effort. 

IFEG
 

Within the IFEG there are various diagrams which illustrate levels of evaluation, starting with a ‘top-level’ view that 

identifies components to consider (Figure 13), and including several detailed flow charts and process for 

component evaluation (e.g., smoke filling, occupant pre-movement time, etc.). 

Construction, Commissioning 

Managtement, Use & 

Maintenance 

1.2.13 

Report 

1.11 

Conclusions 

Acceptable? 

1.10 

Yes 

No 

Select Methods of Analysis 

1.2.9.4 

Carry out 

Analysis 

1.3-1.5 

Collate & Evaluate Results 

1.10 

Redundancy Studies 

1.2.9.5 

Uncertainty Studies 

1.2.9.5 

Sensitivity Studies 

1.2.9.5 

Acceptance Criteria 

1.2.10 

Safety Factors 

1.2.9.2 

Comparative Approach 

1.2.9.1 4a 

Deterministic Approach 

1.2.9.3 4c 

Figure 63 

20 
 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

For each sub-system, a description is provide and flow charts are included which indicate how analysis may be 

undertaken. IFEG Section 1.4.1 notes that these charts are only for guidance, and do not necessarily cover all the 

factors which may be relevant to a particular case. An example from sub system 1 ‘fire initiation and development’ 

is shown as an illustration in Figure 14 below. 

FEB 

FEB 

FEB Fuel 

FEB Geometry 

FEB Openings 

SS-D Automatic 

SS-E Occupants 

SS-F Fire services 

SS-B Ventilations 

SS-BC Openings 

SS-F Fire services 

Initiation 

Schematic 

design fire 

Determine initial heat realease 

rate & other parameters 

characteristics 

Ventilation 

Changed? 

Fire 

suppression 

activated 

Flashover 

occured? 

Fuel becoming 

depleted? 

End time 

reached? 

Terminate 

Modify heat release rate 

& other parameters 

Modify heat release rate 

& other parameters 

Modify heat release rate 

& other parameters 

Modify heat release rate 

& other parameters 

Increment 

time 

1 

2 

5 

7 

9 

8 

6 

3 

4 

Yes 

Yes 

Yes 

Yes 

No 

No 

No 

No 

No 

Yes 

Initiation 

HRR 

Flame height 

Temperature 

Radiation Yields at source

 -species

 -smoke 

to SS-B, SS-C, SS-D, 

SS-E & SS-F 

Time to flashover to SS-F 

HRR 

Time decay starts to SS-C 

HRR 

Time of burnout to SS-C 

Quatified design fire to 

SS-B, SS-C & SS-D 

Figure 7: Flow chart from IFEG for sub-system on fire initiation and development 

21 
 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

SFPE GUIDE
 

Much like the IFEG, the SFPE Guide provides some general flowcharts for guiding evaluation, but notes that 

specifics are left to the designer and the ‘subsystem’ of focus. An overview of the approach is shown in Figure 15 

below. 

Select 

Candidate 

Design 

Evaluate Candidate 

Design in Each Design 

Fire 

Do More Candidate 

Designs Remain? 

Does Candidate Design Meet 

All Performance Criteria in 

Each Design Fire? 

Were Any Candidate 

Designs Successful? 

Select Final Design from 

Acceptable Designs 

Modify or Dismiss 

Candidate Design 

Modify Stakeholder 

Objectives 

No 

Yes 

No 

Yes 

Figure 8: Flow chart for evaluating trial designs 

While not illustrated in the above figure, the SFPE Guide allows for deterministic or probabilistic analysis. Guidance 

is provided in various chapters of the Guide as well as in appendices. It is noted that the level of evaluation should 

match the need of the project and the problem, and can range from application of simple analytical relationships 

and hand calculations to complex computers simulation for deterministic analyses, and qualitative to quantitative 

risk and probabilistic analyses. 

There are also flowcharts provided to aid evaluation of the selected designs based on their focus (e.g., fire spread, 

smoke spread, ...). This is illustrated in Figures 16-19 below. 

22 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

Start 

Yes Is the Barrier
 

Open?
 

No 

Is the Barrier No Open to an Adjacent 

Space? 

Yes 

Calculate Enclosure 

Temperature Assume Ignition in 

Adjacent Space? 

No 

Calcualte Heat 

Transfer through 

Opening 

Calculate Heat Transfer and 

Temperature of Target 

Compare to Failure 

Criteria 

Are Failure Criteria 

Exceeded? Is t> tmax? 

t ∆+ t 

Yes 

No 

Yes 

Yes Record Time of 

Failure 

End 

Figure 9: Flow chart for evaluating fire spread from enclosure 

23 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

Start Start 

Determine the Scope of the 

Space to Analyze 

Determine the Travel Time 

to a Specified Location 

Determine the Response 

Time of Occupants 

Determine the Characteristics of the 

Detection System Being Evaluated (Mode 

of Detection, Activation Threshold) 

Determine Ambient (Nonfire) 

Conditions at the Detector 

t=tig 

Determine the Conditions 

at the Detector 

Record Activation Time 

End 

Did the 

Detector 

Activate? 

Is This a Place No 

of Safety? 

No 

Yes 

Yes 

End 

Record Evacuation Time 

t = t + ∆t 

Figure 10: Flow chart for estimating detector activation Figure 18: Flow chart for determining occupant escape time 

Start 

Determine the Scope of 

the Location of Interest 

No Has Smoke 

Control Operated? 

Yes 

Determine Smoke 

Generation, Flow into, 

and Flow out of the 

Location of Interest 

Determine Smoke Generation, 

Flow into, and Flow out of the 

Location of Interest Considering 

the Effect of Smoke Control 

Calcualte Quantities of 

Interest (Smoke 

Temperature, Species 

Concentration) 

Determine the 

Effects of Effluent 

at the Location of 

Interest 

Figure 19: Flow chart for evaluating smoke development 

24 
 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

ISO TR 13387-1
 

Much like BS7974, ISO 13387-1 provides general guidance, with detailed methodologies being provided in 

reference standards (e.g., deterministic methods are given in the documents dealing with the subsystems, ISO/TR 

13387-4, ISO/TR 13387-5, ISO/TR 13387-6, ISO/TR 13387-7.) 

Like the IFEG, SFPE and BS7974, ISO 13387-1 states that the type of analysis to be provided needs to be carefully 

considered, with it being imperative that the type of analysis fits the needs of the situation. For example, if the 

time of egress for a uniform crowd needs to be determined, then a hand calculation may be sufficient. However, if 

the effect of smoke movement is going to be involved then a more detailed model may be needed. The types of 

methods recommended include: 

• Simple calculation 

• Computer-based deterministic analysis 

• Probabilistic studies 

• Experimental methods 

25 
 

 

 

 

 

Comparison of IFEG, ISO, SFPE and BS7974	 Summary Report 

VARIABILITY & UNCERTAINTY 

This section overviews how the considered documents address issues of uncertainty and variability in analysis and 

design. For the most part, all documents handle this in a general way, identifying that uncertainty is a concern, but 

in few instances provided details as to how to undertake uncertainty and sensitivity analyses (which are referenced 

to other sources). 

BS7974
 

Analysis of variability and uncertainty within the BS 7974 approach is addressed in BSPD7974-7, which can be 

applied to any of the other subsystems. This document was not reviewed in detail as part of the comparison. 

IFEG
 

Part 1 Section 2 describes the process of analysis. In this section safety factors, sensitivity studies, redundancy 

studies, and uncertainty studies are discussed. The factors of safety are listed as: 

•	 The extent of redundancy in the trial design 

•	 The reliability of the various components of the fire safety system 

•	 The analysis methods used 

•	 The assumptions made for the analysis 

•	 The results of an uncertainty analysis 

•	 The acceptance criteria used 

•	 The consequences of a fire 

SFPE GUIDE
 

Section 10.5 of the SFPE discusses the variability and uncertainty in performance based design. There are 6 main 

principles that must be followed: 

1)	 The engineering design process must provide a level of assurance that the designed system or component 

achieves its performance criteria for the design fire scenarios. The analysis must account for expected 

variations in materials, components, demands, performance, and occupant characteristics. In 

prescriptive-based code designs, an unstated excess capacity is used to address variations. (The required 

design might actually perform better than necessary.) Prescriptive-based code designs with an 

engineering basis could prescribe a minimum safety factor in an attempt to compensate for unknown 

variables. This safety factor is derived from either practical experience or estimates of appropriate 

conservatism. The safety factor commonly applied in a structural stress analysis is an example. 

2)	 For performance-based designs, an allowance must be included to account for unknowns and variations 

and to provide a level of confidence in the final design. This allowance could be based on historically 

derived safety factors, an uncertainty analysis, or analysis margins. Each of these techniques is described 

in future sections 

3)	 Assumptions, limitations in calculation procedures, and variability in actual versus evaluated scenarios 

result in uncertainty. Therefore, including explicit uncertainty or safety factors in deterministic-based 

system-performance evaluations might be appropriate. However, unnecessary or excessive use of safety 

factors should be avoided if the basic assumptions and calculation procedures are known or have been 

demonstrated to be highly conservative. 

26 
 

 

Comparison of IFEG, ISO, SFPE and BS7974	 Summary Report 

4)	 Detains on available computer models might not allow explicit evaluation of uncertainty. Conservative 

approaches to design fire scenarios and performance criteria could be utilized to address uncertainty and 

safety factors. 

5)	 The engineer, in consultation with other stakeholders, should determine whether it is appropriate to 

include explicit safety factors within the evaluation, or whether the assumptions and calculation 

procedures are intrinsically and sufficiently conservative. 

6)	 When safety factors are not used, the engineer should understand not only the theory behind uncertainty 

or margin analysis but also its application to a complex fire protection engineering design 

Other sections in 10.5 address Uncertainty in the Engineering Design Process, Safety Factors, Classical Uncertainty 

Analysis, Input Uncertainties, Construction and Use Variations, Analysis Margin, Importance Analysis, and 

Sensitivity Analysis. 

Uncertainty in the Engineering Design Process includes: 

•	 Uncertainties about the science and engineering being used 

o	 Theory and Model Uncertainties 

o	 Data and Model Inputs 

o	 Calculation Limitations 

o	 Design Fire Scenario Selection 

•	 Uncertainties about human behaviors during a fire 

•	 Uncertainties about risk perceptions, attitudes, and values 

ISO TR 13387-1
 

The ISO standard acknowledges 4 main areas of uncertainty: 

1.	 The choice and definition of the scenario(s) 

2.	 The formulation of an appropriate conceptual model for a chosen scenario 

3.	 The formulation of the associated computational model 

4.	 The input data and other chosen parameters 

ISO 13387-1 states that the uncertainties from each stage should be combined to get an overall level of 

uncertainty. It is acknowledged that the level of uncertainty for all steps may not be determined and that there is 

not a “generally accepted methodology for combining them”. Annex E describes these problems in more detail. 

Until a generally accepted methodology can be identified, safety factors used in the proposed solution will need to 

have a “degree of professional judgment”. 

27 
 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

DOCUMENTATION 

This section overviews key elements of the analysis and design which should be documented. 

BS7974
 

The BS 7974 requires a Qualitative design review (QDR), which includes the following components. A report with 

the evaluation methods used, and analysis against the criteria, is to be provided at the project completion. 

• Scope of the Project 

• Relevant Stakeholders 

• Principal Building Characteristics 

• Dominant Occupant Characteristics 

• General Objectives 

• Hazards and Preventive and Protective Measures Available 

• Trial Designs for Assessment 

• Non-compliance Issues and Specific Objectives or Performance Requirements 

• Approaches and Methods of Analysis 

• Acceptance Criteria and Factors of Safety for the Analysis 

• Fire Scenarios and Parameters for Design Fires 

• Parameters for Design Occupant Groups 

• Standards of Constructions, Commissioning, Management, Use and Maintenance 

IFEG
 

The IFEG process documents the initial agreements and analysis in the Fire Engineering Brief (FEB). The FEB 

contains the following: 

• Scope of the project 

• Relevant stakeholders 

• Principal building characteristics 

• Dominant occupant characteristics 

• General objectives 

• Hazards and preventive and protective measures available 

• Trial designs for evaluation 

• Anon-compliance issues and specific objectives or performance requirements 

• Approaches and methods of analysis 

• Acceptance criteria and factors of safety for analysis 

• Fire scenarios and parameters for design fires 

• Parameters for design occupant groups 

• Standards of construction, commissioning, management, use and maintenance 

Designs are then evaluated and a final report is made. The following format is recommended: 

• Executive Summary 

• Introduction 

28 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

• Fire Engineering Brief 

• Analysis 

• Collating and Evaluating the Results 

• Conclusions 

• References 

• Appendices 

SFPE GUIDE
 

The SFPE Guide outlines three major documentation components: Fire Protection Engineering Design Brief 

(Chapter 11), Performance-Based Design Report (Chapter 12) and Supporting Documentation (Chapter 12). 

The following content is recommended for the FPEDB: 

• Project scope and definition 

• Documentation of project participants 

• Participants’ qualifications 

• General project information 

• Description of building and occupant characteristics 

• Project goals 

• Project objectives 

• Performance criteria 

• Design fire scenarios 

• One or more trial designs 

• Critical design assumptions 

• Critical design features 

• Levels and methods of evaluation 

• References 

• Record of agreement of the above 

The following content is recommended for the FP Design Report: 

• Project scope 

• Project participants 

• Goals and objectives 

• Performance criteria 

• Fire scenarios and design fire scenarios 

• Final design 

• Evaluation 

• Critical design features and assumptions 

• References 

Associated with, but separate from, the Design report are the following: 

• Drawings and specifications (may be separate document) 

• Test plan and documentation 

• Field change reporting and documentation 

29 
 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

• Verification of compliance 

• Operating and maintenance manual 

ISO TR 13387-1
 

As with the other processed, application of the ISO process culminates in a report. The report format can vary 

depending on the needs of the particular situation, however it is recommended that the text summarize the study 

and the detailed portions (calculations, computer outputs, etc.) be in the appendix. Typically the following 

components are included: 

• Objectives and scope of the assessment 

• Description of the building and its fire safety installations 

• Description and characteristics of the occupants 

• Fire safety objectives 

• Results of the qualitative design review 

• Basis for selecting fire scenarios for analysis 

• Acceptance criteria 

• Trial designs 

• Any influences of fire safety management 

• Analysis of results, detailing: 

o Assumptions 

o Description of models used and their limitations 

o Input and output data for each subsystem 

o Engineering judgments 

o Calculation procedures 

o Validation of methodologies 

o Sensitivity analyses 

• Comparison of results of analysis with acceptance criteria 

• Fire protection installations 

• Management requirements, including a fire safety manual 

• Conclusions, giving explicitly 

o Requirements for fire protection 

o Any limitations on use 

• References 

o Drawings 

o Design documentation 

o Technical literature 

30 
 

 

Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

SUMMARY 

Based on this review, it is concluded that the International Fire Engineering Guidelines (IFEG) is contemporary in 

scope, process, and general methodologies used with BS 7974, Application of Fire Safety Engineering principles to 

the Design of Buildings, the SFPE Engineering Guide to Performance-Based Fire Protection, and ISO 13387, 

Application of Fire Performance Concepts to Design Objectives. The general framework of all four approaches is 

effectively the same – a result of a high degree of overlap amongst developers of each. In addition, the 

methodologies used and evaluation methods recommended are largely the same. This is a function of the state of 

the art when the guides were developed (all prior to 2005) and the commonality of reference sources across the 

fire engineering community. Likewise, documentation requirements are largely the same. 

In general, BS 7974 includes more detailed methods of evaluation than IFEG, ISO 13387 and the SFPE Guide, as 

these documents refer to other sources (IFEG has more than the other two). Each refers often to the SFPE 

Handbook of Fire Protection Engineering as well as to relevant standards. It is also worth noting that ISO has 

numerous ‘sub-standards’ – by which I mean standards that link to ISO 13387 – which include much more detailed 

methodologies across all areas (fire, smoke, detection, etc.). While this makes the ISO ‘suite’ the most 

comprehensive, it may be considered by some cost-prohibitive. 

One area lacking in the IFEG, ISO and SFPE Guide, as compared with BS 7974, is risk assessment and probabilistic 

methods. While IFEG, ISO and SFPE Guide all include some guidance, they largely refer out to other documents. 

SFPE has a guide on fire risk assessment, and ISO has a standard on fire risk assessment, for example, while BS 

7974 includes probabilistic risk assessment as Part 7 of the package. While it was decided not to include guidelines 

currently under development (e.g., Nordic, European and others), the probabilistic approach is one area which 

these new documents are including. 

31 
Comparison of IFEG, ISO, SFPE and BS7974 Summary Report 

DETAILED COMPARISON TABLES 

32
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – pre-flashover 

IFEG BS 7974 SFPE ISO 13387 Comments 

Ignition It is appreciated that in most 

cases a deterministic approach 

is utilized and a fire initiation is 

a presumption for the fire 

engineered analysis. The use of 

event trees to determine fire 

ignition and spread is 

recognized. Some information 

is provided on ignition 

characteristics. Time to ignition 

of second object is discussed. 

The time to flame contact is 

given as a conservative value. 

For fire spread through 

radiation Babrauskas 

relationship between mass loss 

rate and ignition distance is 

shown. Data is provided on 

ignitability limits for common 

fuels for both piloted ignition. 

Extensive references to 

Babrauskas “Ignition 

Handbook”. 

A list of common ignition 

sources is provided. 

Many factors can affect fire 

development including: 

- Form of ignition 

source 

- Type of fuel first 

ignited 

- Secondary fuels 

ignited and fire 

spread 

Various documents are referred 

to: 

Engineering Guide- Piloted 

Ignition of Solid Materials 

Under Radiant Exposure 

“Flaming Ignition of Solid Fuels” 

(Kanury)- SFPE Handbook 3rd 

Ed. 

“Generation of Heat and 

Chemical Compounds in Fires,” 

(Tewarson) Ch 3-4 SFPE 

Handbook of Fire Protection 

Engineering 

“Will the Second Item Ignite” 

(Babruaskas) 

In deterministic fire safety ignition is 

often assumed to occur and no 

calculations on the ignition process 

are needed. Evaluation of ignition is 

needed to evaluate if one product can 

be replaced by another. It is also 

often necessary to determine if a 

potential ignition source is likely to 

cause ignition of adjacent items. A 

design tree is provided with factors to 

consider when assessing ignition 

potential. Heat-conduction theory 

equation is given for ignition delay of 

thermally thick materials and 

thermally thin materials. The ignition 

of solids is discussed in: 

“Will the Second Item Ignite?” 

(Babrauskas) 

“The Growth of Fire- Ignition to Full 

Involvement, in Combustion 

Fundamentals in Fire” (Thomas) 

NA. The IFEG is more detailed 

and also provides more 

references for additional 

information. SFPE also 

provides addition references 

for more information. 

Fire Load 

Densities 

Allowed to be assessed by 

surveys. 

Allowed to be assessed by 

surveys. 

Fuel load of the building should 

be estimated. 

Fuel loads should be assessed 

based on: 

- State (Solid, liquid, 

gas) 

- Type and quantity of 

fuel 

- Fuel configuration 

- Fuel location 

- Rate of heat release 

- Rate of fire growth 

- Production rate of 

combustion product 

Factors that need to be considered 

- Nature of combustibles 

- Geometric arrangement of 

the fuel 

- Geometry of the enclosure 

- Ignitability of the fuel 

- Rate of heat release 

characteristics 

- Ventilation 

- External heat flux 

- Exposed surface area 

Experimental data is also available. 

Refers to “Ignition of liquid fuels” 

(Kanury). 

Identical. Both use the same 

equation for fire load density. 

SFPE is similar. 

Comparison of IFEG, BS7974, SFPE and ISO 1
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – pre-flashover 

IFEG BS 7974 SFPE ISO 13387 Comments 

Generic data- Swiss data 

collected 1967-1969, it is also 

reproduced in WarringtonBCjC’s “Fire resistant barriers 

and structures (2000)” The CIB 

W14 workshop report is also 

referred to. 

Generic data- The CIB W14 

workshop report is referred to. 

The CIB W14 report is referred 

to for fuel loads for various 

occupancy types. 

Refers to: Fuel Properties and 

Combustion Data SFPE 

Tables and Charts (Babruaskas) 

FPH 

Similar. IFEG provides more 

information. SFPE refers to 

other documents for 

additional information 

Where the CIB W14 workshop 

figures are utilized, it is 

recommended the 95% fractile 

value should be taken as the 

fire load. 

Where the CIB W14 workshop 

figures are utilized, it is 

recommended that in the UK 

the 80% fractile value should 

be taken as the fire load. 

“Where there is expected to be 

limited control over the fuel 

load a conservative estimate 

should be developed” 

Contradicting 

Heat release 

rates 

Convective fraction is 

approximated to 70% of total 

heat release. 

Data for convective heat 

release fractions rates refers 

to SFPE handbook. 

Multiple sources are provided: 

ASTM E1591, Standard Guide 

for Obtaining Data for 

Deterministic Fire Models 

The SFPE Handbook- “Heat 

Release Rates” (Babrauskas) 

“Upholstered Furniture HRR 

measured with a Furniture 

Calorimerter” (Babrauskas, 

Lawson, Walton, Twilley) 

Heat Release in Fires 

(Babrauskas & Grayson) 

CIBSE Guide E Fire Engineering 

2003 

2005 Ed. of International Fire 

Engineering Guidelines 

NFPA 130 Standard for Fixed 

Guideway Transit Systems 

Burning rates of materials and 

products are referenced to: 

“Calorimetry” SFPE Handbook of Fire 

Protection Engineering (Janssens) 

“Generation of Heat and Chemical 

Compounds in Fires” SFPE Handbook 

of Fire Protection of Engineering 

(Tewarson) 

“Burning Rates” SFPE Handbook of 

Fire Protection of Engineering 

(Babrauskas) 

“Fire Safety of Upholstered 

Furninture” (Sundstrom) 

NA. SFPE refers to various 

documents for additional 

information 

No recommendation on an 

appropriate heat release 

model. 

Q*-Dimensionless heat release 

rate as described by Zukoski, 

referred to Drysdale-An 

introduction to fire dynamics. 

“Several methods can be used 

to define a design fire curve: 

using published data, fire 

testing, or calculating a 

theoretical fire size.” 

Comparison of IFEG, BS7974, SFPE and ISO 2
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – pre-flashover 

IFEG BS 7974 SFPE ISO 13387 Comments 

Characteristic 

fire growth 

curves- t2 

“Growth times” referenced to 

NFPA 204. 

Fire growth parameters as 

described in NFPA 92B. 

The following documents were 

referred to: 

NFPA 92B 2005 Ed. and PD 

7974 parts 0-8 2002 Ed. are 

referred to 

The rate of fire growth in stored 

goods may be obtained from NFPA 

204 and SFPE Handbook 

Similar/Identical 

Occupancy related fire growth Picture gallery-slow Similar/Identical 

times referenced to NFPA 204. Dwelling-medium 

Office-medium 

Hotel reception-medium 

Hotel bedroom-medium 

Shop-fast 

Industrial storage or plant 

room-Ultra-fast 

Heat release 

rates per unit 

area 

No recommendations on peak 

heat release rates. 

Shops- 550 kw/m2 

Offices- 290 kw/m2 

Hotel rooms- 250 kw/m2 

Industrial (excl storage)- 90-

620 kw/m2 

NA- More info in 7974 

Smoldering Equation developed by Equation developed by Little data available. Need to Currently no quantitative methods. IFEG and 7974 are identical 

fires Quintere et al. (1982). Quintere et al. (1982). choose carefully in developing 

any specific relationship for the 

design fire curve heat release 

rate. Smoldering fire can cause 

fatalities or damage to critical 

targets before established 

burning 

Need to consider: 

-presence of materials prone to 

smoldering 

-presence of potential ignition 

sources 

and provide more information 

than SFPE 

Heat release 

within 

enclosure for 

flashover 

Walton & Thomas (2002) 

equation for heat release rates 

needed to induce flash-over. 

Walton & Thomas (2002) 

equation for heat release rates 

needed to induce flash-over. 

Following document was 

referred to: 

Fundamentals of Enclosure Fire 

Zone Models (Quintiere) 

The upper part of the enclosure will 

have a hot gas layer. As the 

temperature of the upper layer 

approaches 500oC the heat flux 

becomes so high that flashover may 

occur 

IFEG and 7974 are identical. 

Noted misprint in IFEG on 

definition of terms. SFPE 

refers to a different document 

Temperature 

within 

enclosure prior 

to flashover 

No recommendations. Equation presented by 

McCaffrey et al. 1981 

recommended. 

NA 

Flame length 

for axisymmetric fire 

source 

Flame length is estimated with 

the McAffrey and 

Heskestadequations. 

Flame length according to Cox 

and Chitty, 1980. 

(0.2*Q^(2/5)) 

Flame size is directly proportional to 

the rate of heat release in the fire. 

Refers to Flame Heights and Fire 

Hazard Calculations for Large Open 

Hydrocarbon Fires both in SFPE 

Handbook 

Dissimilar, but not 

contradicting 

Flame length 

for line sources 

No recommendations. The equation shown is 

referenced to DD240-1. 

NA-7974 provides more 

information. 

Comparison of IFEG, BS7974, SFPE and ISO 3
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – pre-flashover 

IFEG BS 7974 SFPE ISO 13387 Comments 

Flame lengths No recommendations. “Corner room fires are likely to NA- 7974 provides more 

for corner room increase flame heights by 75% information. 

and wall fires. and wall fires by 32%” this is 

referenced to Zukoski. 

Flame 

temperature 

Heskestad (2002) equations. No recommendations. Refers to Chemistry and Physics 

of Fire (Drysdale) FPH 

NA- IFEG provides greater 

detail. SFPE refers to a 

different document 

Flame radiation Standard radiation If the flame length is over 1 m Refers to IFEG and 7974 are identical. 

& flame calculations. The emissivity and the flame is luminous it is Engineering Guide to Assessing SFPE refers to a separate 

emissivity can be conservatively set to 1. common to assume black body 

behavior. Emissivity = 1. 

Standard radiation calculation 

with view factor. It is 

suggested that the influence of 

air flow should be taken into 

account. 

Flame Radiation to External 

Targets from Liquid Pool Fires 

document 

Smoke yield No relationships are given for 

mass conversion factors. A 

basic equation is shown 

Smoke mass conversion 

factors for flaming and nonflaming combustion. The 

smoke mass conversion factors 

are referenced to the SFPE 

handbook. 

The following document was 

referred to: 

“Generation of Heat and 

Chemical Compounds in Fires” 

SFPE 

If it is a smoldering fire or if the area 

of interest is far from the point of fire 

origin: 

Assuming no gases leak out from the 

room: C(t) = 1

Vencl

∫ ṁi(t)dt t

0

If the volume flow rate into and out of 

the enclosure are known: 

C(t) = 1

Vencl

∫ [Cin(t) − Ci(t)]V(t)dt t

0

NA-7974 provides more 

information. SFPE refers to a 

separate document 

Optical density The light depletion equations 

is Bouguer’s law. It is however 

shown in the fire detection 

section. 

The light depletion equations 

is Bouguer’s law. 

Different systems of units are used to 

describe smoke density. Annex A of 

ISO 13387-4. It is recommended to 

use the natural-logarithm-based 

system of units: 

K = 1 

l

ln

I0

I

IFEG and 7974 are identical 

Optical density data required Optical density given in dB/m. Refers to: 

for smoke detector activation SFPE Handbook 

is expressed in dB/m. Introduction to Fire Dynamics 

(Drysdale) 

Combustion Fundamentals in Fire 

(Cox) 

Mass optical No discussion on mass optical Relations for mass optical NA- 7974 provides more 

density density. density for different fuels is 

shown. Referenced to SFPE 

handbook. 

information 

Comparison of IFEG, BS7974, SFPE and ISO 4
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – pre-flashover 

IFEG BS 7974 SFPE ISO 13387 Comments 

Visibility No discussion on visibility of 

signage etc. 

S=(10/D), S=visibility distance, 

D=optical density db/m. If a 

sign is back illuminated its 

visibility distance can be 

increased by a factor of 2.5. 

The following documents were 

referred to: 

“Behavioral Response to Fire 

and Smoke” (Bryan) SFPE 

“An Introduction to Fire 

Dynamics” (Drysdale) 

“Smoke Production and 

Properties” (Mulholland) 

“Toxicity Assessment of 

Combustion Products” (Purser) 

SFPE 

NA- 7974 provides more 

information. SFPE provides 

multiple sources 

Mass CO yield factors referenced to The mass conversion factor for Refers to Generation of Heat CO: mco = fco ∗ mfuel NA- 7974 provides more 

production of “part three of these CO is given as 0.013 mf. This and Chemical Compounds in Under post-flashover conditions, information. SFPE refers to 

CO and other guidelines” no data is however value, and other conversion Fires (Tewarson) there are no definitive fco values so outside source 

species found in the appendices. The 

equations shown are basic 

concentration equations. 

factors, is referenced to the 

SFPE handbook. 

0.2 may be used 

CO2: 

fCO2 = 44

MM of simple empirical chemical formula

Hydrogen Cyanide: fHCN = 27

MM of simple empirical chemical formula

Hydrogen Halides: MM of halide

MM of simple empirical chemical formula

Also refers to for a discussion of 

species generation. 

Comparison of IFEG, BS7974, SFPE and ISO 5
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – flashover 

IFEG BS 7974 SFPE ISO 13387 Comments 

Time to 

flashover 

Flashover occurs when the hot 

layer temperature reaches 

approximately 600o

C or when 

radiation at floor level from 

the hot smoke layer reaches 

20kW/m2 

“Flashover can be assumed to 

occur when sustained flaming 

from combustibles reaches 

that ceiling and the 

temperature of the hot gas 

layer is between 550oC and 

600o

C. If flames from the 

combustibles do not reach the 

ceiling, or the temperature 

remains below 550o

C flashover 

can be assumed to be 

unlikely.” 

The following factors will affect 

the time to flashover: 

- Surface area of the 

enclosure 

- The area of enclosure 

openings 

- Te effective height of 

enclosure openings 

- Heat release rate 

- Ventilation 

- Thermal properties of 

compartment 

boundaries 

The heat release rate and other 

characteristics following flashover 

should be based upon those 

applicable to a fuel-bed-controlled or 

ventilation-controlled fire. 

IFEG and 7974 are similar. 

SFPE lists factors affecting 

flashover 

When 80% of the fuel has been 

consumed the fire can be 

assumed to decay either: 

-linearly 

-at rate determined 

experimentally 

-at any rate that can be 

justified 

For design purposes it may be 

assumed that heat release 

rates remain constant until 

80% of the fuel has been 

consumed and the decay 

phase starts. Kawagoe and 

Sekine equation for linear 

decline 

IFEG and 7974 are similar 

Heat release Thomas (1981) for no Walton & Thomas (2002) for IFEG and 7974 are identical for 

rate at consideration of wall thermal no consideration to wall cases where no consideration 

flashover properties. No 

recommendations for thermal 

effects of enclosures. 

thermal properties. McCaffrey 

for when thermal effects of 

enclosures is considered. 

is taken for thermal effects of 

enclosures. 7974 provides 

further information. 

Comparison of IFEG, BS7974, SFPE and ISO 6
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 1 – Initiation and development of fire within enclosure of origin – steady burning 

IFEG BS 7974 SFPE ISO 13387 Comments 

Mass burning Uses Drysdales’ equation for Uses Thomas, 1973, equation for the Not Rate of burning can be determined from IFEG, BS7974 and ISO are 

rate in mass flow, with a reasonable mass flow in an underventilated fire or addressed consideration of air flowing into the similar 

ventilation and referenced assumption an unreferenced equation for fuel mass compartment. Refers to Estimating 

controlled 

conditions 

regarding underventilated 

fires. 

flow (it is identical to the one in Drysdale 

1999). 

Temperatures in Compartments (SFPEWilliam, Walton, Thomas). 

The energy release rate can be determined 

from consideration of the effective heat of 

combustion of the fuel. Refers to An 

Introduction to Fire Dynamics (Drysdale). 

Mass burning No equations are suggested. An effective fire duration of 20 minutes Not The burning rate of fuel-bed-controlled fires is Different in all 

rate in fuel bed References are made to can be assumed in houses, offices, and addressed dependent upon the nature and geometric 

controlled Babrauskas section in the SFPE shops. Burning rate is based on arrangement of the fuel. The rate of burning 

conditions handbook and Sardqvists 

“Initial fires”. It is 

recommended that 

“appropriate engineering 

judgement” should be applied 

when setting fire rates. 

assessment that the total initial fire load 

burns in 1200 seconds. Another equation 

for fuel bed controlled fires is presented 

with no reference to its origins. Time to 

reach burnout after flashover is shown as 

two times the mass of fuel left at 

flashover divided by peak rate mass 

burning rate. 

is dependent upon the surface area of the 

fuel. Refers to Burning Rates (SFPE HandbookBabrauskas). 

Standard 

temperaturetime curve 

Short discussion on the 

existence of empirical timetemperature curves. Reference 

given to Lie (1994). 

Recognizes the ISO and BS 476 

temperature-time curve. 

Not 

addressed 

Under the furnace fire section: 

Standard temperature-time curve equation:

Tg = Ta345 log10(8t + 1)

BS7974 and ISO 13387 provide 

many equations and data 

while the information found in 

IFEG is very limited. Hydrocarbon 

temperaturetime curve 

Large pool fire, in accordance with BS 

476-20. 

Not 

addressed 

Under the furnace fire section: 

Hydrocarbon temperature-time curve 

equation:

Tg = 1080(1 − 0.325e0.167t − 0.675e−2.5t)

+ Ta

Temperature curve in accordance with 

BS EN 1991-1-2:2002. 

Not 

addressed 

Other temperature-time curves are specified 

in national and ISO test methods for testing a 

range of products or specific applications. 

Their application in fire safety engineering is 

therefore limited. They may be useful when 

comparison needs to be made to performance 

determined during the test 

Slow heating 

curve 

Two heating curves for slow heating fires. 

Reference to BS 1363-2:1999. 

Not 

addressed 

Maximum 

temperature 

curve 

Equation referenced to M.law 1978. Not 

addressed 

Ventilation Kawagoe and Sekine equation dependent Not 

controlled on opening factor. addressed 

temperaturetime curve 

Comparison of IFEG, BS7974, SFPE and ISO 7
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – design objectives and strategies 

IFEG BS 7974 SFPE ISO 13387 Comments 

Design 

Objectives 

Evaluate effect on Means of 

Escape [MoE]. 

Protection of MoE- clear layer 

solutions. 

The following document was 

referred to: 

NFPA 204, Guide for Smoke and 

Heating Venting. 

IFEG and 7974 are identical. 

SFPE refers to another 

document 

Temperature control 

mentioned with regards to fire 

spread. 

Temperature Control- protects 

materials within the smoke 

zone. 

IFEG and 7974 are similarboth outline advantages of 

controlling temperatures 

Evaluate effect on FF 

operations 

Assist fire fighting operationsprevent hot smoky layers 

occurring in certain situations. 

IFEG and 7974 are identical 

Property Protection- limiting 

heat flux on structure through 

exhaust. 

N/A- No mention in IFEG of 

limiting heat fluxes 

Techniques Containment mentioned. Smoke containment- physical 

measures to prevent the 

spread of hot and smoky 

products- smoke curtains, 

walls etc. 

IFEG and 7974 are similar 

Extraction mentioned. Smoke clearance- removal of 

smoke after smoke has 

finished being produced. 

IFEG and 7974 are similar 

Dilution mentioned. Smoke dilution- mixing smoke 

with clean air to reduce the 

concentration of toxic 

products and increase 

visibility. 

IFEG and 7974 are similar 

Natural ventilation mentioned. Smoke exaust ventilationnatural or mechanical means 

of removing smoke from top 

of layer. 

IFEG and 7974 are similar 

Zone pressurization 

mentioned. 

Pressurization- effectively 

contains smoke. Uses pressure 

differences over openings. 

IFEG and 7974 are similar 

Depressurization- limiting 

smoke movement by pressure 

differentials. Fans pull air out 

of designated spaces rather 

than supplying it. 

N/A- depressurization not 

mentioned in IFEG 

Comparison of IFEG, BS7974, SFPE and ISO 8
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – design procedure and analysis 

IFEG BS 7974 SFPE ISO 13387 Comments 

Inputs Building characteristics, heat 

release rate profile, smoke 

yield, characteristics, of smoke 

management equipment, time 

to smoke detection, 

environmental effects 

Building characteristics 

Occupant characteristics 

Design fire- sub system 1 

Environmental influences- wind, internal air 

movement, stack effect. 

Active systems activation time. 

Refers to 

• International Fire 

Engineering Guidelines 

• ISO TR 13887 

• PD 7974 Parts 0-8, 

Application of Fire Safety 

Engineering Principles to 

the design of buildings 

• Global Performance-Based 

Design: Is it the Solution? 

(Reiss) 

• Evaluation of 

Unsprinklered Fire Hazards 

(Alpert and Ward) 

• Introduction to the Use of 

Fire Dynamics in 

Performance Based Design 

(Custer) 

• Introduction to 

Performance Based Fire 

Safety (Custer and 

Meacham) 

• “Performance-Based Fire 

Scenarios” Primer #3 

• “Goals, Objectives & 

Performance Criteria” 

Primer #1 

IFEG and 7974 are 

identical. SFPE refers to 

multiple documents 

Heat Content of 

Plume 

Qc=0.7Q Qp=XQ where X is the fraction of heat as 

convection (0.4-0.9). Table provided for 

different fuels. 

The following document was 

referred to: 

“Compartment FireGenerated Environment and 

Smoke Filling” (Cooper) SFPE 

Handbook 

Smoke Control in Fire Safety 

Design (Properties of Fire 

Plumes- Zukoski) 

Smoke Controle in Fire 

Safety Design (Fire PlumesHeskestad) 

Smoke Control in Fire Safety 

Design (Air entrainment into 

buoyant jet flames and pool 

fires- Delichatsios) 

Usually, the heat release 

IFEG and 7974 are 

dissimilar, but not 

contradicting. More 

information in 7974 

Smoke Plumes 

Above Fire 

Source 

Mean flame height and virtual 

origin mentioned. 

Luminous flame height- Cox and Chitty or 

Heskestad- whichever is more onerous. 

Calculations outlined for flame height and mass 

flow rate of smoke and entrained air. 

IFEG and 7974 are 

dissimilar, but not 

contradicting. More 

detail in BS 7974. SFPE 

refers to another 

document 

McCaffrey Model- equations Axi-symmetric plumes: Discussion about the IFEG and 7974 are 

given for mass entrainment movement of smoke and air entrainment. rate in the plume equals the dissimilar, but not 

rate for flame region, convective fraction of heat contradicting. BS 7974 

intermittent flame region and release rate. The convective has greater detail and 

buoyant plume. heat release rate is typically commentary. 

Comparison of IFEG, BS7974, SFPE and ISO 9
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – design procedure and analysis 

IFEG BS 7974 SFPE ISO 13387 Comments 

Smoke Plumes 

Above Fire 

Source 

Not mentioned. Line Plume: Where L=5W of fire base. Flame 

height, mass flow of smoke. Dependant on 

length of side and HRR. 

assumed to be 70% of the 

total heat release rate. 

McCaffrey plume expression 

is also referred to Purely 

Buoyant Diffusion Flames: 

Some Experimental Results 

(McCaffrey). This would use 

the total heat release rate. 

N/A- not mentioned in 

IFEG 

References the use of 

reflection (Mowrer and 

Williamson 1987). No 

calculation given. 

Effect o fAdjacent Walls: the reduction of 

entrained air from the perimeter causes the 

flame height to lengthen. Flame height and 

mass floor of smoke given for fire against wall 

and in corner. 

IFEG and 7974 are 

dissimilar, but not 

contradicting. More 

detail in BS 7974 

Not mentioned. Fire induced winds: inlet air velocity causes the 

flame jet to move away from opening. Mass 

flow of smoke can be calculated. 

N/A- BS 7974 has more 

information 

Stack effect makes reference Stratification of Smoke: two equations for IFEG and 7974 are 

to Klote and Milke (2002). stratification of smoke rise (m). Dependant on dissimilar, but not 

Equation given for vertical temperature and height of rise. contradicting. 

smoke flow rate (kg/s) 

Ceiling Jets Ceiling jet mentioned in 

detection sub system. Short 

explanation. 

Plume impingement on ceiling. Ceiling jets are 

typically 5-12% of fire source to ceiling height 

in depth. Maximum velocities and 

temperatures occur in first 1% of fire source to 

ceiling height. 

The following document was 

referred to: 

“Compartment FireGenerated Environment and 

Smoke Filling” (Cooper) SFPE 

Handbook 

Defines a ceiling jet. For 

commonly used expressions 

refers to: 

Calculation of Response 

Time of Ceiling Mounted Fire 

Detectors (Alpert) 

Smoke Control in Fire Safety 

Design (Evans) 

Dissimilar, but not 

contradicting- BS 7974 

goes into more detail. 

SFPE refers to another 

document 

Axi-symmetric ceiling jet: 

temperatures and velocities in 

unconfined spaces discussed. 

Equations outline the 

maximum temperature rise 

and maximum gas velocities 

and is dependent on the radial 

distances and height of ceiling 

above the fire source (Alpert 

1972). 

Axi-symmetric ceiling jet: temperatures and 

velocities in unconfined spaces discussed. 

Equations outline the maximum temperature 

rise and maximum gas velocities and is 

dependent on the radial distance and height of 

ceiling above the fire source (Alpert 1972). 

IFEG and 7974 are 

identical 

References Delichatsios (1981). Two-dimensions ceiling jet: Where beams or 

corridors inhibit plume spread, the velocity and 

temperature rises will be different to 

unenclosed spaces. The velocity and 

temperature rises are dependent on the width 

of the corridor and the distance to a point 

which wants to be found (Delichatsios 1981) 

IFEG and 7974 have 

identical references-BS 

7974 goes into more 

detail 

Flow from Rockett (1976) and Edmonds Calculation of mass flow of smoke from a Dissimilar, but not 

enclosure (2002) equation given for mass vertical opening before the onset of flashover is contradicting. 

openings flow out of an opening. 

Dependent on density of 

smoke and opening. 

considered (Thomas 1992). This is based on the 

temperature rise, air density, depth of smoke 

layer and the profile correction factor. Depth of 

smoke layer is presented based on a constant 

of proportionality. 

Comparison of IFEG, BS7974, SFPE and ISO 10
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – design procedure and analysis 

IFEG BS 7974 SFPE ISO 13387 Comments 

Flow from 

enclosure 

openings 

Smoke spread from other than 

the enclosure of fire origin is 

stated as being difficult using 

hand calculations are rarely 

used although SFPE handbook 

has some calculations. 

Spill Plumes: discusses the effect of large spill 

areas. Large uncertainties can be involved. The 

mass flow rates include the effect of the width 

of the opening. Calculations for mass flow of 

smoke presented. 

Dissimilar, but not 

contradicting. BS 7974 

provides greater 

discussion and provides 

hand calculations. 

Flow through a horizontal vent Flow of hot gases through natural horizontal IFEG and 7974 are 

references Klote and Milke vents: calculation given to determine the mass similar- Different 

(2002). Equation given for flow rate through a horizontal vent (Thomas et equations with same 

vertical smoke flow. al 1963). basis used. 

Replacement 

Air 

Briefly mentioned. Essential for inlet to be provided, maximum 

speed 5 m/s. 

BS 7974 provides more 

detail 

Properties of 

Smoke 

Upper temperature of layer 

from McCaffrey. Dependent on 

openings, materials in room 

and fire size. 

Temperature of the hot gases: represented by 

the relationship between fire size and mass 

flow of smoke. 

Referred to Effect of 

Combustion Conditions on 

Species Production (Gottuk & 

Lattimer) SFPE 

If it is a smoldering fire or if 

the area of interest is far 

from the point of fire origin, 

the temperature of the fire 

effluent may not be high 

enough for stratification to 

occur. 

Dissimilar, but not 

contradicting. 

Not mentioned. Smoke volume flow rate: well mixed smoke 

layer volume flow rate represented by 

temperature and mass flow of the smoke. 

N/A- BS 7974 goes into 

more detail 

Optical density of smoke: Optical density of smoke: expression given on Smoke density can be N/A- BS 7974 goes into 

expression given on the way the way light is attenuated in respect to source estimated by assuming the more detail 

light is attenuated in respect to intensity and the optical density of smoke. The space to be well-stirred 

source intensity and the optical density of smoke is a function of the 

optical density of smoke. total volume of smoke and the mass optical 

density of the fuel. 

Visibility through smoke is not 

given. Optical density per unit 

length can be found. 

Visibility through smoke: visibility through the 

smoke is one over the optical density per unit 

length (Tewarson 1995). 

IFEG and 7974 are 

similar- BS 7974 goes 

into more detail 

Short discussion on the use of Gas species mass concentrations: discussion Dissimilar, but not 

gas species concentrations. about the means by which the mass contradicting. Greater 

Consideration required for concentration of a particular species can be detail in BS 7974 

certain toxins when related to found. 

life safety. 

Not mentioned. Gas volume concentrations: dependant on the 

density of species. 

N/A- BS 7974 goes into 

more detail. 

Smoke No information given, Limits for smoke reservoir sizes in the absence Dissimilar, but not 

Reservoir Size references made to; Drysdale 

(1999), SFPE Handbook 

(DiNenno 2002), Evans and 

Klote (2003). Refers to NFPA 

92B and NFPA 204. 

of computer modeling to 2000m2 for MoE, 

2600m2 for powered and 3000m2 for property. 

contradicting. Greater 

detail in BS 7974 

Comparison of IFEG, BS7974, SFPE and ISO 11
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – design procedure and analysis 

IFEG BS 7974 SFPE ISO 13387 Comments 

Minimum 

Number of 

Exhaust 

Ventilators 

Refers to NFPA 92B and NFPA 

204 

The phenomenon of plug holing is discussed 

and the calculation for critical exhaust rate of 

ventilators away from a wall is given from BRE 

368. The number of vents can be found from 

the mcrit and the mass flow entering the layer. 

N/A- BS 7974 goes into 

more detail. 

Interactions of 

Sprinklers and 

Smoke 

Ventilation 

Not mentioned. Referenced to BRE 368 to determine whether 

sprinklers will affect the designed smoke 

control system and the effect the temperature 

control will have on the sprinkler system. 

N/A- BS 7974 goes into 

more detail. 

Free hanging 

Smoke Curtains 

Of Plume 

Not mentioned. Discussion on the problems associated with 

free hanging smoke curtains and horizontal 

deflections. 

N/A- BS 7974 goes into 

more detail. 

Not mentioned. Curtains containing a smoke layer: the 

deflection of the smoke curtain can be 

N/A- BS 7974 goes into 

more detail. 

calculated from the parameters of the curtain 

and projected smoke layer. Length of curtain 

required is iterative. 

Not mentioned. Curtains closing and opening: deflection of N/A- BS 7974 goes into 

curtain and length can be found. more detail. 

Comparison of IFEG, BS7974, SFPE and ISO 12
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – smoke hazards 

IFEG BS 7974 SFPE ISO 13387 Comments 

Hazards of Visible and non visible product “airborne” products of IFEG and 7974 are 

smoke of combustion or pyrolysis and combustions, solid or liquid similar/Identical 

entrained air particulates within a gaseous 

mass. 

“CO, CO2, and HCN are often Most fire deaths from smoke IFEG and 7974 are similar 

considered for life safety inhalation. 

criteria.” CO2, H2O, CO, HCN. Further 

preamble of smoke dangers. 

Smoke 

Dynamics 

Influence of buoyancy and 

combustion generated 

products. Amount of air 

entrained greatly exceeds 

mass flow of fuel burned. 

Initial flow influenced by air 

currents; fuel controlled fire 

creats a plume, smoke rises to 

ceiling, then radially spreads. 

Air entrainment increases 

IFEG and 7974 are dissimilar, 

but not contradicting. 

colume and decreases 

temperature. 

Fire growth may be limited by 

limited ventilation. 

Comparison of IFEG, BS7974, SFPE and ISO 13
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 2 – smoke control – management, data and summary 

IFEG BS 7974 SFPE ISO 13387 Comments 

Fire Safety 

Management 

Suggest management 

procedures for active systems 

particularly and consideration 

required for passive systems. 

Defines the use of BS 9999:4 

to determine frequency of 

maintenance. 

IFEG goes into more detail. 

Data 0.7 referred to as standard for Convected fractions for N/A- BS 7974 goes into more 

Convected fractions various materials. detail. 

Means of determining Mass 

Optical Density via use of 

extinction coefficient. 

Mass optical densities and CO 

yield of various materials. 

N/A- BS 7974 goes into more 

detail. 

Computer 

Modeling 

Mentioned as a means of 

analysis, no advice given. 

Discussion of model types, 

zone models, CFD, thermal 

radiation etc. 

The following documents were 

referred to: 

Introduction to Performance 

Based Fire Safety (Custer and 

Meacham) 

Engineering Guide- Evaluation 

of the Computer Fire Model 

DETACT-QS 

“An Updated International 

Survey of Computer Models for 

Fire and Smoke” (Carpenter 

and Olenick) 

“Deterministic Computer Fire 

Models,” (Walton, Carpenter, 

Budnick) 

Potential computer models are 

named in each subsection (Under part 

7). 

N/A- BS 7974 goes into more 

detail. SFPE provides many 

references to documents for 

additional information 

Summary Where calculations and 

concepts are not given, 

reference one of a number of 

books/papers. Good flow chart 

of procedures. Some details 

are brief. Some information in 

other sub-systems. 

Provides defined areas to 

provide smoke ventilation and 

smoke control in enclosures 

and large spaces. 

Mostly refers out to other 

documents 

Mostly addressed in sub-system 

details 

IFEG and 7974 provide the 

answers, although only BS 

7974 provides them within the 

document. IFEG references 

other document heavily, some 

widely-used calculations are 

not present. 

Comparison of IFEG, BS7974, SFPE and ISO 14
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 3 – structural and passive fire protection – fire spread analysis 

IFEG BS 7974 SFPE ISO 13387 Comments 

General The recommended approach 

to determining the appropriate 

fire resistance of barriers is to 

utilize the time equivalence 

model and then use a barrier 

that can achieve the resulting 

fire period. 

Design guidance on openings into fire 

enclosure: 

-Doors should be assumed open if 

enclosure has no other openings 

-Doors should be assumed closed if 

the enclosure has other openings 

-All enclosure surfaces (including 

glazed openings) may be assumed to 

be imperforate for the duration of 

fire provided analysis hasn’t proved 

otherwise. 

-Monte Carlo analysis is 

recommended to evaluate 

combinations of openings. 

The following documents 

were referred to: 

An Introduction to Fire 

Dynamics (Drysdale) 

Surface Flame Spread 

(Quintiere) 

N/A 

Heat Flow by 

Conduction 

No information given. Designer should take “great care” if 

deciding to use a criterion of a 

surface temperature on the 

unexposed side in excess of 200OC. 

Refers to Chemistry and 

Physics of Fire (Drysdale) 

Classical textbooks on heat 

transfer provide innumerable 

hand calculation expressions for 

calculating heat fluxes to and 

from solids, liquids, and gases as 

N/A- 7974 provides quantified 

guidance. SFPE references 

another source 

Heat Flow by No information given. Criteria of 500O

C can be used when Refers to Chemistry and N/A- 7974 provides quantified 

Convection establishing likelihood of 

spontaneous ignition due to 

convection only. Piloted ignition is 

assumed to be probable in the region 

400-450O

C. Some criteria given for 

human tolerability levels, 60O

C 

saturated air is mentioned as 

intolerable. 

Physics of Fire (Drysdale) well as expressions for estimating 

the resulting temperature profiles 

in a target. These analytical 

expressions are usually arrived at 

by setting up the energy balance. 

guidance. SFPE references 

another source 

Heat Flow by Various references to Standard radiation relationships Refers to Chemistry and N/A- 7974 provides quantified 

Radiation publications regarding external 

fire spread. Some data on 

ignitability limits under radiant 

heat flux. The spontaneous 

ignition criterion for wood is 

set to 250-400O

C. 

shown. 12.6kW/m2 is mentioned as a 

criterion, giving “some factor fo 

safety”. Possible to base analysis on 

the increase of surface temperature 

of the object exposed. For organic 

solids a surface temp. criterion of 

600O

C is suggested for spontaneous 

ignition, and 300-410O

C for ignition 

by flying brands under a radiative 

heat flux. 

Physics of Fire (Drysdale) guidance. IFEG provides a 

short commentary and 

references to other guidance 

documents. Only very brief 

quantified guidance on 

ignitability. 

Some dissimilarity in criteria 

for ignition of solids. 

SFPE references another 

source 

Heat Flow by 

Mass Transfer 

BS 476-3 is recommended for a 

methodology assessing the 

ignitability of roof coverings 

subject to radiative heat fluxes 

and flying brands. 

Presence of flying brands hard to 

determine with any certainty. Should 

be considered as piloted ignition 

leads to lower necessary surface 

temperatures. 

N/A- IFEG provides a very 

short commentary, but does 

reference a test method for 

assessing ignitability of 

surfaces exposed to flying 

Design care should be taken to mass brands. 7974 does not provide 

Comparison of IFEG, BS7974, SFPE and ISO 15
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 3 – structural and passive fire protection – fire spread analysis 

IFEG BS 7974 SFPE ISO 13387 Comments 

flow of burning liquids. any quantified guidance. 

Heat Flow by No information given. A reasonable design approach is to N/A- Some practical guidance 

Direct Pyrolysis assume that all combustibles within from 7974. No guidance in 

and Reaction to enclosure will at some point become IFEG. 

Fire involved in the fire. Any part of 

continuous combustible construction 

that extends outside the enclosure 

the enclosure should be viewed as 

permitting fire spread beyond that 

enclosure. 

Fire Spread in It is recognized that assuming It is recognized that the size of the Design Tree Figure 10-4 (Pg Refers to: Similar- The IFEG suggests a 

Large 

Enclosures 

simultaneous combustion in 

enclosures over 150m2 leads to 

unrealistically high 

temperatures in the enclosure. 

It is recommended that the 

floor area should be subdivided into smaller grids (10-

50m2

) and that fire spreads 

from one grid to another. 

enclosure influences the potential 

fire severity and tat a fire in a large 

compartment is more likely to be fuel 

bed controlled than fires in smaller 

compartments. 

116) Toxic Potency Measurement for 

Fire Hazard Analysis (Babrauskas, 

Levin, Gann, Paabo, Harris, 

Peacock, Yusa) 

Combustion Products and their 

Effects on Life Safety (Fire 

Protection Handbook- Yamada 

and Tanaka) 

quantified value, whilst 7974 

only provides a qualitative 

comment. SFPE provides a 

design tree for evaluation 

Computer Provides information on the No information. Refers to Applying Models of Refers to ISO 13387-5 N/A- IFEG provides more 

Models use of computer models in the Fire Protection Engineering information. SFPE refers to 

design process, and what one Problems (Custer) FPH another document 

should keep in mind when 

utilizing computational 

modeling. The models 

discussed are zone and field 

models used to establish fire 

severity. The use of FEM 

models is also discussed. 

Comparison of IFEG, BS7974, SFPE and ISO 16
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 3 – structural and passive fire protection – general issues 

IFEG BS 7974 SFPE ISO 13387 Comments 

Recognition of It is appreciated that the Information from standard Acknowledged that fire testinc Refers to BS 476-32 Fire Tests on Dissimilar, but not 

Fire Tests standard fire test curves do 

not represent a real fire timetests is reasonably well understood. In most cases this 

can be used to collect heat 

release data that may be used 

Building Materials and Structures. contradictory. SFPE provides 

additional references for more 

temperature curve. allows a rapid appraisal of an for a design fire curve Refers to information 

element’s ability to resist fire 

spread and maintain structural 

small scale tests(ASTM E 1321 

and ASTM E 1354) furniture 

function. (ASTM E 1537 and ASTM E 

1590) and room configurations 

(ASTM E 603) 

Refers to following documents: 

The Cone Calorimeter 

(Babrauskas) SFPE 

Heat Release in Fires 

(Babrauskas and Grayson) 

ISO 9705: Full Scale Room Test 

Calorimetry (janssens) SFPE 

Time Recognizes and shows the Recognizes and shows the The recommendations given 

Equivalence Eurocode1 approach. The 

recommended kb value 90.08-

Eurocode1 approach. kb is set 

in a range of 0.09- 0.05 with a 

are similar between the IFEG 

and 7974 publications. They 

0.045) is however higher than recommendation for UK for do however differ from the 

the recommendations given in 0.07. This is higher than the EC1. The EC1 suggests a kb 

EC1. This is referenced to Kirby values found in EC1. ranging between 0.04 and 0.07 

(1999). 

Determination Basic heat balance and Maximum temperature Refers to NFPA 921 Guide for N/A- BS 7974 goes into more 

of Fire references to simple equation shown, as well as a Fire and Explosion detail. 

Conditions relationships. similar equation for through Investigations 

Through 

Engineering 

Calculations 

draught conditions. 

Transient fire conditions 

equations shown from DD ENV 

1991-2-2. 

Comparison of IFEG, BS7974, SFPE and ISO 17
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 3 – structural and passive fire protection – material performance 

IFEG BS 7974 SFPE ISO 13387 Comments 

General Much of the information given 

on this subject seems to be 

taken from a standards 

presented by the American 

Society of Civil Engineers. 

ASCE/SFPE 29, 1999. 

Very detailed on the structural 

performance of different 

construction units in fire conditions. 

Refers to Engineering GuideFire Exposures to Structural 

Elements 

Refers to numerous documents 

including: 

Fire Safety Engineering Design of 

Structures (Purkiss) 

ASTM 685 Design of Buidling for 

Fire Safety (Harmathy) 

Structural Mechanics (SFPE 

Handbook- Fitzgerald) 

N/A- BS 7974 goes into more 

detail. SFPE provides a 

reference for more 

information 

Concrete Simplified design processes for 

reinforced concrete members 

are referenced to a number of 

national standards from 

Australia, New Zeeland, 

Eurocode. 

Empirical equations based on the 

standard time temperature curve to 

predict temperature profiles within 

concrete members. 

The following document was 

referred to: 

“Analytical Methods for 

Determining Fire Resistance 

of Concrete Members 

(Fleishmann and Buchanan) 

Refers to ISO 834-1 test, the 

optimum fire resistance of flexural 

concrete members have been 

observed when tested under 

imposed end restraints of 

between 20-80% 

NA- 7974 contains a lot of 

practical guidance. IFEG 

references to other sources 

and only provides a rough 

commentary. SFPE references 

another source 

Information given on thermal 

elongation and shrinkage, specific 

heat capacitiy, thermal conductivity, 

density, and emissivity. 

Steel Eurocode 3- Design of Steel 

structures is recommended as 

a suitable guide for steel 

design. Guidance is given on 

when FEM methodology 

should be used over simpler 

methodologies. 

Section factors from BS 5950-8 and 

temperature rise within a steel 

member is calculated from DD ENV 

1993 1-2. 

The following document was 

referred to: 

“Analytical Methods for 

Determining Fire Resistance 

of Steel Members” ( Milke) 

Refers to: 

Fire Safety of Bare External 

Structural Steel (Law and O’Brien) 

N/A- IFEG provides a fair bit of 

information on existing 

standards. No practical 

guidance is found in the 

document. 

BS 7974 provides more data 

and guidance in the document 

but other sources will still 

need to be studied to perform 

an analysis. 

SFPE references another 

source 

Information given on thermal 

elongation, specific heat capacity, 

thermal conductivity, density, and 

emissivity. 

Protection to external steel 

member is referenced to Law 

and O’Brien (1981) and EC1 

and EC3. 

Protection to external steel member 

is referenced to Law and O’Brien 

(1981). 

IFEG and 7974 are identical 

Short discussion on the 

possible fire protection 

measures available for steel 

structures. 

Detailed recommendations of 

calculation methodologies for 

protected steel. 

N/A- 7974 provides more 

practical guidance 

Comparison of IFEG, BS7974, SFPE and ISO 18
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 3 – structural and passive fire protection – material performance 

IFEG BS 7974 SFPE ISO 13387 Comments 

Timber Confirms a charring line equal 

to the 300OC line of heating. 

Refers to White (2002) and an 

Australian Standard. EC 5 is 

mentioned as a source of 

charring rate equations. 

The charring rate is estimated using 

Hadvigs (1981) equations. Equations 

for time to maximum charring rate 

and time dependent charring rates 

shown. Charring rates from BS 5268-

4.1 and DD ENV 1995-1-2 is shown. It 

is suggested, in accordance with BS 

5268-4.1, that charring rates to 

columns should be increased by 25% 

compared to a beam. 

The following document was 

referred to: 

“Analytical Methods for 

Determining Fire Resistance 

of Timber Member” (White) 

Refers to: 

“Analytical Methods for 

Determining Fire Resistance of 

Timber Member” (White) 

Dissimilar, but not 

contradictory. IFEG only 

provides a very short 

commentary of timber 

behavior in fire, with 

references to external sources. 

BS 7974 provides more data 

and practical guidance, but 

studies of external sources is 

still necessary for a complete 

Information given on thermal analysis. 

elongation and shrinkage, specific SFPE references another 

heat capacity, thermal conductivity, source 

density and emissivity. 

Masonry Reference for methodologies 

given to Australian Standard 

AS 3700. 

Information given on thermal 

elongation and shrinkage, specific 

heat capacity, thermal conductivity, 

density, and emissivity. 

No specific reference N/A- 7974 provides 

information that is more 

related to thermal properties 

rather than structural design. 

IFEG appreciates that there is 

not much guidance available 

but still references a national 

standard for some guidance. 

Lightweight References given to thermal General description on the fire No specific reference N/A- IFEG does not provide 

Timber/ Steel calculations on lightweight performance of these constructions. any data or practical guidance 

Frame timber walls performed by The structural performance is but refers to a number of 

Assemblies Clancy (1999), Collier (1996) 

and other. Lightweight steel 

frame guidance is referenced 

to Gerlich et al. 

referenced to BS 5268. sources. 

Plastics No information given. Information given on thermal 

elongation and shrinkage, specific 

heat capacity, thermal conductivity, 

density, and emissivity. 

No specific reference N/A- 7974 provides more 

information, mostly on the 

thermal properties but some 

also on structural 

performance. 

Aluminum No information given. Information given on thermal 

elongation and shrinkage, specific 

heat capacity, thermal conductivity, 

density, and emissivity. Some 

guidance on structural stress 

behavior in raised temperatures. 

No specific reference N/A- 7974 provides more 

information 

Comparison of IFEG, BS7974, SFPE and ISO 19
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 4 – fire detection – components 

IFEG BS 7974 SFPE ISO 13387 Comments 

General Extensive references to BS 5839 and 

BS EN 54 

NFPA 72 is referred to The correct type of detection system 

is essential because large numbers of 

false alarms can lead to situation 

where the alarm is ignored by many 

or all. Refers to: 

• Fire Suppression and Detection 

Systems (Bryan) 

•Detector Environment and 

Detector Response: A Survey 

(Holmstedt) 

•Design of Detection Systems (SFPE 

Handbook) 

Different 

Smoke 

Detectors 

Two models mentioned: Optical 

density and Heat detector 

equivalence 

Mentions the research performed 

regarding the temperature rise 

needed to activate a smoke detector. 

Methodology for 

Evaluation of the 

Achievement of Smoke 

Development 

Performance Criteria. 

Figure 10-7 

Refers to: 

•Design of Detection Systems (SFPE 

Handbook) 

• Fire Detection Modeling. State of 

the Art 

• Smoke Production and Properties 

(SFPE Handbook) 

• Modified Theory for the 

Characterization of Ionization 

Smoke Detectors (Newman) 

IFEG and 7974 are identical. 

SFPE provides a design tree 

Smoke detectors are assumed to 

activate when the temperature is 

raised 13O

C above ambient 

(Heskestad 1981). 

13OC above ambient is mentioned A method for 

estimating the detector 

activation time is given 

in Figure 10-5 

For the optical density detection 

model only brief information is 

provided, and a simple 

correlation between light 

depletion and detector threshold. 

It is stated that calculations of the 

optical density should be 

performed for the plume or 

preferably the ceiling jet. 

For flaming fires, DD 240-1 is 

referenced for the equation showed 

for smoke detector activation time. It 

does also require the detectors 

specific sensing threshold. Point-type 

smoke detectors need a surrounding 

air velocity of at least 0.15 m/s to be 

able to detect fire. 

Photoelectric detectors depend on: 

- The time to reach a given smoke 

density at the location of the 

detector 

- The possible time lag due to the 

delay in smoke entering into the 

detector 

- The possible time lag due to the 

response of the sensor to smoke 

inside the detector 

Refers to: 

•NFPA 72: National Fire Alarm Code 

•Design of Detection Systems (SFPE 

Handbook) 

• Fire Detection Modeling. State of 

the Art 

Dissimilar, but not 

contradicting. IFEG does not 

really provide any calculations 

on the activation of smoke 

detectors. 7974 provides 

more practical information, 

especially on the heat 

detector equivalence. 

For non-flaming fires alternative 

method will have to be sought. 

Comparison of IFEG, BS7974, SFPE and ISO 20
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 4 – fire detection – components 

IFEG BS 7974 SFPE ISO 13387 Comments 

Heat Detectors The concept of RTI is described. The concept of RTI is described. Refers to 

• “Design of Detection 

Systems” (Schifiliti, 

Meacham, and 

Custer) in SFPE 

Handbook 

Describes RTI and the conductivity 

factor (c). Refers to Annex B and 

Quantification of Thermal 

Responsiveness of Automatic 

Sprinklers Including Conduction 

Effects (Heskestad). 

IFEG and 7974 are identical. 

SFPE refers to another 

document 

Alpert (1972) ceiling jet model for 

gas temperature and gas velocity 

predictions. Additional equations 

shown for special applications 

such as high ceiling or partially 

confined ceilings. These are 

referenced to NFPA 92B. 

BS EN 54-5 is referenced for tables 

showing detector response times. 

Dissimilar, but not 

contradicting. It should be 

noted that the equations 

shown for heat detector 

activation are quite dissimilar, 

it is however hard to 

determine how much of an 

impact this has on the 

estimation of activation time. 

Quinter et al. (1982) model for temp. 

rise in the hot layer. This is suggested 

as a worst case scenario for 

combined fixed-temperature/heatrise detectors. Qualitative 

commentary on cases where smoke 

spread is confined by beams and 

narrow corridors etc. 

Beam Detectors An unreferenced equation is 

shown for the optical density 

required to cause activation of a 

beam detector. 

A relationship for the obscuration is 

shown. This is referenced to an EN 

standard in draft. EN 54-12. 

Operates on a light obscuration 

principle. For information on 

engineering evaluation of the 

performance and response time of 

light obscuration detector systems 

refers to: 

•Design of Detection Systems (SFPE 

Handbook) 

•Quantification of Thermal 

Responsiveness of Automatic 

Sprinklers Including Conduction 

Effects (Heskestad). 

IFEG and 7974 are similar- The 

equations shown are almost 

the same, but they differ by a 

factor 10. One would think 

that 7974 would therefore be 

expressed in bel rather than 

decibel, but this does not 

seem to be the case. It is 

therefore unclear if the 

references used in the two 

guides are interchangeable. 

Aspirating 

Detectors 

Manufacturers specifications and 

SS-B “smoke development and 

control” parameters. 

British Fire Protection Systems 

Association “COP for Category 1 

Aspirating Detection Systems” (1996) 

is referenced for information. 

N/A 

Each sampling point can be When considering location of smoke IFEG and 7974 are identical 

modeled as an individual point sampling points, the best analogy is 

detector. Lon detection time to consider them as individual point 

delays in large systems. detectors. Long detection time 

delays in large systems. 

Comparison of IFEG, BS7974, SFPE and ISO 21
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 4 – fire detection – components 

IFEG BS 7974 SFPE ISO 13387 Comments 

Linear Heat No information. A brief discussion of the applicability Thermal point or line detectors are N/A- 7974 provides more 

Detectors of linear detectors. The most 

practical way of assessing their 

performance is recommended to be 

by regarding them as a continuous 

line of heat detectors. 

best suited to situation where cost 

and reliability are overriding factors. 

Response can be modeled by 

calculating the heat transfer taking 

place by convection between the gas, 

and the detector, by conduction 

through the detector body to the 

mounting structure and by radiation 

to/from the surroundings. 

information. 

Flame It is recommended that normal SFPE handbook relationship for the Dissimilar, but not 

Detectors radiation and view factor 

equations should be utilized to 

calculate the radiation impinged 

on the detector. 

level of radiation impinged on the 

detector. The SFPE refers to standard 

curves for fire size and distance. The 

BS EN 54-10 standard is mentioned. 

contradicting. 7974 provides 

quantitative guidance. 

Gas Detectors No acceptable methodology 

available for detection times. 

Carbon monoxide detectors 

mentioned, with a relationship for 

the mass flow of CO as a function of 

total mass flow. A threshold value of 

40 ppm is mentioned. 

N/A- 7974 provides more 

information. 

Manual No information. It is recognized that citing and The following N/A- 7974 provides more 

Detection spacing of detectors to a standard 

template (BS 5839-1 mentioned). Is 

not likely to provide the optimum 

performance and that engineered 

layouts can provide a more effective 

system. 

document was referred 

to: 

NFPA 72, National Fire 

Alarm Code. Appendix B 

information. 

Spacing of No information given. Evans (1993) NIST relationship Refers to: N/A 

Detectors between heat release and spray 

density. This is presented as a 

conservative estimate. BS 5306-2 is 

referred to for engineering guidance. 

•NFPA 72: National Fire Alarm Code 

• Fire Suppression and Detection 

Systems (Bryan) 

• Environment and Detector 

Response: A Survey (Holmstedt, 

Magnusson, Thomas) 

•Quantification of Thermal 

Responsiveness of Automatic 

Sprinklers Including Conduction 

Effects (Heskestad). 

• Calculate the Response Time of 

Heat and Smoke Detectors 

Installed Below Large Unobstructed 

Ceilings (Evans, Stroup) 

Comparison of IFEG, BS7974, SFPE and ISO 22
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 4 – fire suppression 

IFEG BS 7974 SFPE ISO 13387 Comments 

Sprinklers Madrzykowski and Vittori General discussion on the Adjustment to HRR curve are Water: Details on how to design a wet system IFEG and 7974 are similar. 

(1992) relationship for heat subject. Reference to NFPA discussed in 9.5.3 references SFPE discusses how the 

release after sprinkler 750 for more information. •Hydraulics(SFPE Handbook) HRR curve may change 

initiation. Evans (1993) NIST • Automatic Sprinkler System Calculations (SFPE 

relationship between spray Handbook) 

density and heat release. An 

extended radius is 

• Suppression (FP Handbook) 

recommended to incorporate 

a degree of conservatism in 

the detection time equations. 

Dry: Activation time is equal to the time it takes 

to expel system air. It should be equal to the 

longest time for suppression agent to expel air 

through the agent outlet at the furthest point 

from the system control valve. 

Water Mist Referred to applicable 

national standard. 

General discussion on the 

subject. Reference to NFPA 

Delay time for discharge on 

wet pipe systems can be 

Activation time is equal to the time it takes for 

suppression agent to expel air in system 

N/A- 7974 provides more 

information, mostly 

750 for more information. ignored. But for dry pipe pipework through the agent outlet in the furthest qualitative but with some 

systems the discharge delays point from the system control valve guidance on high, low, or 

need to be evaluated either medium pressure systems. 

through the SFPE Handbook 

or software 

Gaseous Referred to applicable General discussion on the The literature is referred to for detailed N/A- 7974 provides more 

Suppression national standard. subject. Reference to BS information on the engineering design of such information, such as the 

System ISO 14520 for more 

information. 

systems to minimize activation times 

•Halon Design Calculations (SFPE Handbook) 

•Halon Replacement Clean Agent Total Flooding 

Systems (SFPE Handbook) 

• Carbon Dioxide and Application Systems (FP 

Handbook) 

•Halogenated Agents and Systems (FP 

Handbook) 

• “Self-Heating and Spontaneous Combustion” 

SFPE Handbook (Beever) 

• Self-heating – Evaluating and Controlling the 

Hazards (Bowes) 

• “Calorimetry” SFPE Handbook (Janssens) 

impact of fire growth. 

Foam System No information given. General discussion on the 

subject. Reference to SFPE 

The literature is referred to for details of the 

design process 

N/A- 7974 provides more 

information, such as the 

handbook for more • Foam Agents and AFFF System Design impact of fire growth. 

information. Considerations (SFPE Handbook) 

• Foam System Calculations (SFPE Handbook) 

• Foam Extinguishing Agents and Systems (FP 

Handbook) 

Comparison of IFEG, BS7974, SFPE and ISO 23
 

 

 

 

 

Subsystem 4 – smoke management and exhaust systems 

IFEG BS 7974 SFPE ISO 13387 Comments 

No information given. General discussion on the 

subject, including failure 

modes. 

Process on how to evaluate system design is 

discussed. Refers to: 

NFPA 92B: Guide to Smoke Management Systems 

in Malls, Atria, and Large Areas 

Smoke and Heat Venting (SFPE Handbook) 

“The Growth of Fire- Ignition to Full Involvement, 

in Combustion Fundamentals in Fire” (Thomas) 

“Flammability Limits of Premixed and Diffusion 

Flames” SFPE Handbook (Beyler) 

N/A- 7974 provides more 

information. 

Comparison of IFEG, BS7974, SFPE and ISO 24
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 5 – fire service intervention 

IFEG BS 7974 SFPE ISO 13387 Comments 

Fire Service 

Intervention 

The Australian FBIM (Fire 

Brigade Intervention Model) 

is presented as an appropriate 

method for quantification of 

fire service intervention. 

The time for fire service 

attendance is referenced to 

the Home Office, and a table 

of recommended time limits is 

shown for different areas 

depending on the areas risk 

classification. 

No information given. No information given. NA- IFEG provides a model or a 

framework for fire service 

intervention. 7974 provides 

more information, but this is 

qualitative to a great extent. 

The FBIM employs a 

structured decision-based 

framework necessary both to 

determine and measure fire 

service activities on a time 

line basis. 

The only details to support a 

quantified analysis are the 

recommended time limits and 

a notation that the initiation of 

fire tackling will take “upwards 

10 minutes from the time of 

arrival”. 

The fire service operation is A detailed description of what 

split up into 16 flowcharts. is expected of fire service 

provisions installed in a 

building, but their respective 

relation to fire service 

operations is not thoroughly 

explained. 

The description of the FBIM is 

very much an overview, and 

the IFEG does not cover any 

technical details of fire service 

provisions and operations. 

The FBIM (2004) is referenced 

for quantified estimates for 

each flowchart. 

Very little information on 

where the reader can find 

more information about 

quantified analysis of fire 

service operations. 

Summary The IFEG effectively refers all of it recommendations to the FBIM. It also appreciates that the FBIM is a unique document as Australia is the only country that has produced such 

an extensive quantified guide. It is also appreciated that the guidance given in FBIM is developed with Australian condition in mind, and that the guidance given in the 

document may not be directly applicable to other countries. IT is however suggested that the quantitative guidance in FBIM can be used as a semi-quantitative utility in other 

locations. 

7974-5 is highly qualitative and does not provide any model for setting up a quantified model for fire service intervention. Some quantified guidance on the likely fire service 

response times as a function of the areas UK risk category. 

Comparison of IFEG, BS7974, SFPE and ISO 25
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 6 – Occupant safety 

IFEG BS 7974 SFPE ISO 13387 Comments 

General The Required Time for 

Escape (RSET) is 

divided into a 

detection phase and a 

movement phase. 

A description of 

Available Safe Escape 

Time (ASET) and 

Required Safe Escape 

Time (RSET). 

A design tree for estimating evacuation 

time is given in Figure 10-6 

Total time consists of 2 parts: Total Pre-Movement time 

(sum of Pre-movement recognition time and Premovement response time) and Movement processes 

(estimation of time required for evacuation of 

occupants). 

N/A- The IFEG and 

7974 are similar in 

such that they both 

appreciate the basic 

model for evaluating 

It is recommended A quantified strategy is The following needs to be considered when The following building conditions need to be considered egress time, but 7974 

that Fire engineered proposed, separating developing a possible fire scenario: (more information is given in A.1): provides more 

Solutions should be RSET into sub- - Number of occupants - Layout and geometry information in regards 

based on data in elements, and guidance - Distribution throughout the - Escape routes to the different 

publications such as is given on quantified building - Building use parameters. 

the SFPE handbook values for the time - Alertness - Fire safety management system SFPE provides a design 

and other scientific needed in the different - Commitment - Life safety strategy tree for estimating 

publications. sub-elements. - Focal Point 

- Physical and mental capabilities 

- Role 

- Familiarity 

- Social affiliation 

- Physical physiological condition 

- Training 

The following documents were referred to: 

“The Time Delay to Start Evacuation: 

Review of Five Case Studies,” (Proulux) 

SFPE 

Refers to Engineering Guide to Predicting 

1st and 2nd Degree Skin Burns 

Engineering Guide-Human Beahvior in Fire 

SFPE 

“Emergency Movement” (Nelson, H.E.; 

Mowrer) SFPE 

- Application of active systems 

- Signs and lighting 

- Refuge areas 

- Environmental considerations 

The following occupant characteristics need to be 

considered (more information is given in A.2): 

- Population numbers and density 

- Familiarity with the building 

- Distribution and activities 

- Alertness 

- Mobility 

- Physical and mental ability 

- Social affiliation 

- Role and responsibility 

- Location 

- Commitment 

- Focal point 

- Responsiveness 

- Occupant condition 

• Behavioral Response to Fire and Smoke (SFPE 

Handbook- Bryan) 

• Domestic, multi-occupancy and hospital fires 

(Canter, Breaux) 

• To Prevent Panic in an Underground Emergency, 

Why Not Tell People the Truth? (Proulx, Sime) 

• Timing Human Response in Real Fires (Brennen) 

• The Time Delay to Start Evacuation: Review of Five 

Case Studies (Proulx, Fahy) 

evacuation time and 

refers to additional 

documents 

Comparison of IFEG, BS7974, SFPE and ISO 26
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 6 – Occupant safety 

IFEG BS 7974 SFPE ISO 13387 Comments 

Very little quantitative 

guidance on the subelements of the 

escape time. A list of 

information sources is 

however presented. 

Extensive quantified 

guidance on time to 

detection, travel 

speeds, evacuation 

times etc. given in 

appendices. 

The following documents were referred to: 

“Movement of People: The Evacuation 

Timing” (Proulx) SFPE 

Combustion Products and Their Effect on 

Life Safety (Hartzell) FPH 

Also need to consider 

- Fire alarms and cues available to occupants 

- Fire size and extent, smoke density, toxic gas 

concentrations, temperature and heat flux in 

all building enclosures, activation of 

suppression and smoke control systems. 

A model for travel A tenability criterion is The following document was referred to: A limit for exposure of skin to radiant heat is given as 

times is referenced to given for zero “Behavioral Response to Fire and Smoke” approximately 2.5 kW/m2 . An expression for 

Nelson & Mowrers’ exposure. This is given (Bryan, J.L.) calculating tolerance time is given in ISO 13571. 

work presented in the as a clear layer height Information on exposure to smoke is referenced to 

SFPE handbook. of 2.5m and a smoke 

layer temperature not 

exceeding 200O

C. 

Visibility through Fire Smoke, Part 5 (Jin) and ISO 13571. 

Evaluation of irritant toxic gases is referenced to 

Toxicity Assessment of Combustion Products (Purser) 

and ISO 13571. 

Information on asphyxiant toxic gases Toxicity 

Assessment of Combustion Products (Purser) , 

Combustion Products and Their Effects on Life Safety 

(Hartzell), Behavioral Impairment in Smoke 

Environments (Purser) are referenced and ISO 13571 

Summary The IFEG provides only qualitative guidance and refers extensively to other sources for guidance on several subjects in regards to evacuation. 

7974 provides a mainly qualitative commentary on many different aspects of evacuation times and evacuation behavior. Some quantified guidance is provided, most of the figures 

originates and relates from the UK. The SFPE provides some design trees for analysis but, like the IFEG, it mainly refers to other documents for additional information 

Comparison of IFEG, BS7974, SFPE and ISO 27
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Subsystem 7 – Risk assessment 

IFEG BS 7974 SFPE ISO 13387 Comments 

General The use of a probabilistic approach is 

recognized and described in the 

Overview section of Part 1. 

Three method categories are 

described in some detail: 

-simple statistical analysis 

-logic tree analysis 

-sensitivity analysis 

A section also discusses 

complex analysis tools. 

Appendix E describes Risk 

Analysis methods 

Appendix G describes 

Uncertainty Analysis methods 

“Verification Methods” Primer 

#4 

Not addressed in 13387-1, but there 

is a new standard on fire risk 

assessment, 16732, Fire Safety 

Engineering — Guidance on fire risk 

assessment, which provides 

significant guidance. This was not 

reviewed but is recommended. 

N/A- but it is clear that 7974-7 

provides more detail than 

IFEG. 

One method of probabilistic risk 

assessment is shown. This method is 

based on Beck and Yung’s work, 

presented in 1994. 

It is recognized that the acceptable Acceptance criteria are shown 

risk can be of absolute type or as absolute or comparative. A 

comparative type. For life safety the number of examples of criteria 

result is shown as Occupant safety is shown but it is highlighted 

and Occupant number of deaths. that there is not a generally 

accepted criteria for fire risk in 

the UK. 

It is appreciated that risk analysis can A brief discussion on the Appendix E describes risk 

be used to estimate financial loss. financial aspects of analysis 

Fire Cost Expectation is mentioned. probabilistic risk assessment. 

An example of cost-benefit 

analysis is shown. 

An event tree technique is utilized to 

show different fire scenarios and 

establish the risk parameters. 

Data and information given on 

many of the parameters 

needed in a Probabilistic Fire 

Risk Assessment. 

The use of an event tree is 

recommended. 

A similar methodology is shown for 

estimations of monetary risk. 

No information given on the costbenefit side of fire protection or any 

target values for acceptable fire risk. 

Summary 7974 provides the most guidance, both qualitative and quantitative, on the subject of risk analysis. Different techniques are described and the probability of different aspects of fire 

scenario models is discussed. 

IFEG provides some information on setting up a fire risk assessment and the results of such an analysis. Some quantitative guidance is provided on some parameters of fire scenarios, 

such as ignition frequencies, fire loads and detection/suppression system reliability. 

SFPE is similar to the IFEG. It provides very general information and relies heavily on the references to other documents for qualitative information. NOTE: SFPE has a separate 

guideline on Fire Risk Assessment, which goes into much more detail. 

ISO 16732, Fire Safety Engineering — Guidance on fire risk assessment, provides significant guidance. 

Comparison of IFEG, BS7974, SFPE and ISO 28
Annex C
 

Using A Systems Approach to Assess How Disruptive Events Affect Building
 

Overall Performance
 
 

 

 

 

 

 

 

 

 

 

 

Using A Systems Approach to Assess How Disruptive Events Affect Building Overall Performancea 

Alvarez-Rodriquez, A.i,*, Meacham, B. J.,ii Dembsey, N.A.ii, Thomas, J.R.iii 

i

AON Fire Protection Engineering, Lincolnshire, IL, USA 

iiDepartment of Protection Engineering, Worcester Polytechnic Institute, Worcester, MA, USA 

iiiNational Research Council Canada, Ottawa, Ontario, Canada 

*

corresponding author: alberto.alvarez-rodriguez@aon.com 

Abstract 

A building project implies the participation of different groups of stakeholders, including contractors, 

building owners and users, architects, engineers, and the authority having jurisdiction which approves the 

construction and the use of the project. The concept of performance-based design has been used for 

decades, although it has implied setting different objectives for each of these groups according to their 

mandates. The overall building performance depends on the interrelations between the different building 

components such as the architectural system, the interior environment system, and components used for 

emergency situations. This article focuses on how events such as fires or any other emergency situations 

can affect the performance of buildings during such events, particularly considering how the actual use of 

a building might vary from design phase assumptions to post occupancy conditions, and how ignoring 

such factors may lead eventually to some emergency components being misused by the building 

occupants or used in unintended ways. To address these concerns, a risk-informed performance-based 

design process has been developed within a new building performance paradigm, organized around 

systems formed by the coupling of specific building types, the activities being undertaken in the buildings 

and the building occupants (building-occupant systems). 

Keywords: Building performance; performance-based fire protection design; fire safety engineering; 

systems approach 

Introduction 

While a wide range of definitions and criteria exist in the literature, it is suggested that main drivers for 

application of performance-based design (PBD) include demands from stakeholders for better building 

performance in use across a wide range of stakeholder expectations, in conjunction with a changes in 

legislation allow a broader use of engineered options instead of simply fulfilling prescriptive 

requirements. Within a PBD framework, the demand of the "end users" of the building (i.e. building 

occupants) become priorities [1] so that PBD provides a more "client" oriented process [2] than the one 

used when following building code regulations. 

a Unpublished manuscript, to be submitted for peer review. 

1/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Conceptually, a PBD approach can be applied to all the components of a building project, including 

among others, acoustics, aesthetics, operability, sustainability, and safety. It involves numerous actors, 

including on one hand the building users who should define the level of performance of the building, and 

on the other hand, the building industry which should create optimal solutions in order to achieve this 

level of performance within a regulatory framework established by policy makers. 

Because of the complexity of the engineering thinking related to these building components, PBD 

guidance has been (a) segmented such that each engineering discipline has to consider separately how 

clients' objectives connected with each of the building components should be achieved, and (b) 

‘genericized’ to accommodate multiple solutions. This applies not only to design of building components 

dedicated to the normal use of the building (e.g., mechanical components including heating, ventilation, 

and air conditioning (HVAC) and plumbing) but it also to building components installed to address 

disruptive events, such as fires, earthquakes, or any type of emergencies susceptible to affect the safety of 

building occupants or damage the building contents and structure. As such, while PBD guidance has thus 

far been elaborated to treat discipline-specific ‘normal’ building performance (e.g., energy, HVAC, etc.) 

and specific safety objectives (e.g. fire [3] and earthquakes [4]) those conducting analyses must have 

specialized expertise, and there is little integration across or between disciplines. 

However, in practice, the building end users are not really interested in the performance of individual 

building components and systems, but rather, the performance of the building as a whole [5]. To achieve 

this, the design team is expected to address the multitude of building components and systems and have 

them co-operate in order to achieve this seamless daily performance [6] for both normal use and during 

and after disruptive events. This does not always occur as well as would be hoped. 

The research presented in this article originated from a review of decades of worldwide experience of the 

performance-based option for fire protection design, which identified shortcomings in the interpretation, 

application and implementation of performance-based fire protection design (PBFPD) processes [7]. It 

was observed that the aim of these processes is centered on the design of fire protection measures, and not 

building performance. As a result, the application of current PBFPD processes may lead to the possibility 

that these measures, deemed appropriate at the building design stage, might be ignored or worse 

"rejected" by the building end users when needed the most. By looking at performance-based approaches 

used to deal with earthquakes [4], it was realized that this observation can be generalized to any disruptive 

event and mitigation strategies. To address these challenges, a new paradigm for building performance 

was developed around the concept of ‘building-occupant’ systems, for which a new risk-informed, 

performance-based analysis and design approach was structured. This paper presents the outcomes of the 

research, specifically related to the treatment of disruptive events on the overall performance of a building 

project, using fire as an example: 

•	 First, a system formed by specific building types and their associated occupants is defined, so as to 

characterize the nature of disruptive events and theirs effects on the overall performance of that 

system; 

•	 Second, within this system paradigm, a risk informed performance-based design process is 

established, with the aim that this process would be applicable to any disruptive event and include a 

step evaluating the integration of the protection measures into the considered system. 

2/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Decrease of the building performance during a disruptive event 

Primary stakeholders in a building project, including the building owner and the potential end users, 

generally define building performance objectives in terms of the everyday uses of the building. For a 

hospital, this performance is mainly related to the type of treatments offered, the number of patients who 

can be treated, the types of equipment and services needed to treat patients. For a school, this performance 

is primarily related to delivering education to the specific student populations, the number of registered 

students, the numbers and qualification of teachers or faculty required to deliver education. For a 

museum, it is mainly related to its exhibits and holdings in terms of circulation and storage, security and 

controlled environment and then to the number of exhibition attendees who can be accommodated [28]. 

We call these specific coupling of building use and user performance expectations ‘building-occupant’ 

systems (see more detailed discussion later in the paper). Unfortunately, while designing or operating a 

building, the primary stakeholders of the building do not always think about all the possible, often low 

frequency events, that may affect the daily performance of the building, either at the level of a specific 

building-occupant system, or as part of a larger social or economic system. 

At a generic level, the nature of disruptive events which could affect the daily performance of a buildingoccupant system on its own or as part of a larger social or economic system can vary significantly, 

including [8]: 

•	 supplier business disruption leading to operational vulnerabilities, 

•	 fires originated inside or outside a building, earthquakes, severe weather, accidents or terrorism 

leading to hazard vulnerabilities, 

•	 currency exchange fluctuations leading to financial vulnerabilities, 

•	 new competition leading to strategic vulnerabilities. 

We focus here on as specific part of the problem: disruptive events for which building components could 

be designed so to mitigate the effects of these events, such as natural and technological hazards. Such 

disruptive events can significantly impact the operation of a building and the mission it supports at the 

building-occupant system level or at a broader social or economic system level. If the building owner and 

other key actors are unprepared, the disruptive event can have catastrophic effects on continued 

operations [9]. Because PBFPD processes have been developed for decades, this article focuses on fires 

as an example of a class of disruptive events. 

Characterization of a disruptive event affecting the performance of a building 

To show the importance of considering potential impacts on a building to be analyzed, as part of a larger 

social or economic system network, let us describe the events that started with a small fire in a 

manufacturing plant in USA and ended up with a US$2.34 billion loss for one of the plant’s clients. This 

example is taken from Sheffi's book "The Resilient Enterprise" [8]. On March 17, 2000, lighting struck 

the industrial plant of Philips NV, located in Albuquerque, New Mexico, USA. As a consequence a small 

fire started within the facility but was extinguished by sprinklers and staff in less than 10 minutes. There 

were no injuries and the fire fighters arrived at the plant just to record a minor blaze. From a fire 

protection engineering design perspective this could be considered a success, with systems operating as 

intended. However, due to ensuing activities, the damage to the plant contents and disruption to the plant 

activity was tremendous. So why was the disruption so significant? 

3/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

First, the plant was engaged in manufacturing of semiconductor chips for some 30 clients, including the 

mobile phones companies Nokia and Ericsson, whose orders accounted for 40 percent of the Albuquerque 

plant’s production. Indeed, a semiconductor manufacturing facility such as this cannot tolerate any dirt or 

particulate in normal activities, in any of its clean rooms, much less soot in case of a fire. Not only did the 

fire destroy the chip batches in the furnace (with an equivalent of thousands of mobile phone production) 

but also smoke, soot and the tramping of staff and fire fighters from the fire scene (in the mix of dirt and 

water) contaminated chips at every stage of the production, increasing that loss to millions of mobile 

phone chips. The losses for Philips did not stop at the ones related to property damage. Removing the dirt 

from the clean rooms implied that the production would be back up after one week. This was the Philips 

estimation right after the fire, but two weeks later, Philips staff realized that the disruption caused by the 

fire would take weeks before production could restart. When two of the main clients of Philips, Nokia and 

Ericsson received the call from Philips on March 20, they each dealt differently with this situation, which 

ended up with two very different business outcomes. 1 Figure 1 illustrates the profile of the 

aforementioned Philips fire, adapted from [8]. Prior to the fire, the plant is performing at a certain level, 

i.e. it is manufacturing (x) chips for its clients. The disruptive event occurs and the performance of the 

plant decreases, leading to a full impact of a completely stopped production. In our case, the performance 

of the plant went down to zero for weeks. The full impact was the sum of the direct consequence of the 

fire (damage to the furnace and smoke spread) and of the indirect consequence of the fire fighting 

operations (staff and fire fighters walking all around the plant and contaminating all the remaining 

furnaces). The recovery time was not the expected one week but several weeks. A long term impact was 

observed, as Nokia engineers sent to the Philips plant in the recovery phase ended up with increasing the 

pre-event production rate. 

Pre- event Post- event 

"chronic" state "chronic" state 

Figure 1 "Disruptive event" profile of the Philips Plant fire, adapted from [8] 

Performance of the Philips Plant: daily number of chips produced

The 10 minute fire is extinguished by sprinklers and staff intervention 

Chips on the furnace where the fire started are lost 

Chips on all the plant are lost and the whole plant production isstopped

Several weeks to restore the clean rooms 

Smoke spread and tramping of staff and fire fighters from the 

fire scene (in the mix of dirt and water) contaminate chips at 

every stage of the production 

Full impact of the fire event 

Preparation for Recovery 

Long term 

impact 

Fire disruptive event 

Restarting 

productio 

n 

Fire scenario: 

from ignition to 

extinguishment 

Fire event: 

between two 

"chronic" states 

of the system 

Time 

4/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

For the authority having jurisdiction (AHJ) approving the use of the plant, the life safety objective was 

not compromised. Related to fire safety, the plant could have been "code compliant" or designed to 

perform as well as a building provided with regulatory requirements. With regard to property protection 

objectives, the fire did not lead to severe damage of the production line in itself, but it contaminated all 

the production (with the involuntary help of the staff and fire fighters). It should be noted that Philips 

adopted a risk transfer towards insurance companies and hardly "suffered" from the disruptive event. On 

the long term, even if its premium may be more expensive, the subsequent boost of production may have 

compensated for the monetary loss. However, not all entities that suffer such disruptions are so lucky [9]. 

While currently available PBD guidance for fire suggests that engineers consider impact on mission 

continuity, they provide no guidance as to how this should be accomplished and at what level the impact 

should be considered (e.g., building only, raw materials, complete supply chain, etc.). As such, research 

has shown that this aspect is often ignored or inadequately addressed [7]. 

Reaching a post event "chronic" state for all building components 

The actions required in the recovery phase need specific documentation to insure that all building 

components including the ones related to disruptive events, are back in full operational mode. This 

specific need is illustrated by the fires that successively occurred in a New Orleans warehouse (Louisiana, 

USA), on March 21, 1996 [7, 27]. A first arson type fire successively started in a low rack section 

unprotected by in-rack sprinklers, was detected by staff who unsuccessfully tried to extinguish it, 

activated one over-head sprinkler which action did not extinguish nor control the fire, and eventually was 

declared out by the fire fighters, about 5 hours after they arrived on site. At that point, “once fire control 

had been achieved, all of the sprinkler systems in the facility were manually shut down by closing the 

individual OS&Y valves on the risers”, as a result of the opening of numerous sprinkler heads throughout 

the warehouse, causing extensive water damage. Without evaluating the damage to the electrical system 

caused by water, the electric service of the building was restored, starting the second fire, in a high rack 

storage area, by ignition of combustible materials with arcing of damage wiring in this area. "As soon as 

the second fire was discovered, facility personnel began opening the OS&Y valves on the ceiling and inrack sprinkler systems. However, because these systems were impaired during the initial stages of the 

second fire, they were overwhelmed". This time, the fire destroyed all the contents of the warehouse and 

collapsed the structure. The second fire was declared out several days after the fire fighters arrived a 

second time on site. 

This example illustrates the importance of the actions to be performed and the needed documentation (as 

procedures or check-lists) in the recovery period, after the fire is extinguished. These actions not only 

concerned the impaired fire protection system but also one utility system to the warehouse, i.e. electricity. 

The authors of the investigation report [27] advocated for a utility restoration in a "planned and 

coordinated manner, and only after a complete survey of the damage has been taken" so "that everyone 

involved with the overhaul and restoration operations be aware of what actions are being taken by the 

different agencies and services involved". Nevertheless, they "were unable to identify any reference in an 

NFPA standard, code, or recommended practice that addressed the issue of restoration of utilities and how 

it should be handled following an emergency". The lack of checking the electrical system after the first 

fire may be explained by the staff will to go back to production as soon as possible as this business 

objective trumped the competing objective related to work in a safe environment2

. 

5/29 
 

 

 

 

 

 

 

 

 

 

 

 

Identifying the effects of competing objectives related to the usages of a building 

Generally speaking, a building is designed by architects to perform according to "chronic" (every day) 

objectives. From a societal point of view, a "chronic" objective for hospitals is to cure sick or injured 

patients, and for schools to educate people. In addition, various societal goals are intrinsically embedded 

in the design of buildings, such as safeguarding people who use the buildings. While life safety from fire 

is the focus of most fire protection engineering analyses, a fire is an “acute” event, not often (or ever) 

expected by users, and competing objectives may exist between such an “acute” objective of fire safety 

and the "chronic" objectives of a building. 

Competing objectives at a design stage 

When looking for the goals and objectives that are relevant for the different stakeholders involved in a 

building project, a FPE also has to verify that the safety objectives related to the fire risk involving this 

project are not competing with all the other stakeholders' objectives. Let's see how this point is already 

considered in the current PBFPD processes. For example, the International Fire Engineering Guidelines 

(IFEG) [16] indicate that "in addition [to general regulatory objectives], the client may have various nonfire related objectives for the building design that impact on the fire safety of the building. For example, 

the client may require: 

• Increased security 

• Extensive natural lighting 

• An open plan layout 

• The use of new materials 

• Measure to improve energy efficiency and sustainability 

• Flexibility for future uses 

• Low life-cycle cost." 

Unfortunately, the IFEG do not provide any guidance on how to consider these additional objectives, 

which can be competing with the ones related to fire safety. As a result, there is currently no guidance for 

managing competing objectives in current PBFPD processes during the design stage. If the FPE happens 

to identify and address such issues through discussion with stakeholders, it is more by experience or 

chance than by direction. 

Adding competing objectives after the design stage 

Building stakeholders may decide to establish additional "chronic" objectives, at some time after the 

original design phase, when the building is actually operating. For example, as a result of the 

11 September 2001 events that occurred in the USA, increased security at airports multiplied check points 

that may impede safe egress capabilities in the case of an emergency. It should be noted that increased 

security has now become a "chronic" condition, not only for that type of transportation but also in major 

crowd gathering events. Besides, adding more security check points concentrate people in certain areas, 

people that are managed to follow predefined and controlled paths. Not only does this security crowd 

management condition compete with the conditions employed for dealing with emergency situations (fire 

or other disruptive event), but it also competes with the original "chronic" objective of the architectural 

design. For example, Figure 2, which visually translates the ideal vision of the designer to have 

6/29 
 

 

 

 

uncongested pedestrian movement in the airport, as well as the aesthetic goal to have passengers walking 

in a quiet, spacious environment, contrasts with Figure 3, which illustrated the real situations of airports. 

a) Barcelona Airport Terminal 1
 

source: http://www.flickr.com/photos/francesc_2000/4583309008/, 

free to share and remix with the attribution of the work to 

Francesc_2000
 

b) Hong Kong Airport Terminal 2
 

source: http://www.flickr.com/photos/gkpics/953052759/, free to
 

share and remix with the attribution of the work to jgmarcelino
 

Figure 2 Examples of airport architectural designs 

a) source: http://www.public-domain-image.com/full-image/peoplepublic-domain-images-pictures/crowd-public-domain-imagespictures/airport-security-lines.jpg-copyright-friendly-image.html, in 

the public domain, Author: Kitt Hodsden 

b) Palma de Mallorca Airport
 

source: http://www.flickr.com/photos/kalleboo/3536493996/, free 

to share and remix with the attribution of the work to Karl Baron
 

Figure 3 Examples of impacts of the security "chronic" condition in airports 

This is something that does not only concern engineers dealing with disruptive events but also architects, 

building owners and operators as well as building occupants who have to deal with changes between the 

original conceptual design of the building and the subsequent building usages, including changes in the 

building interior design and attributes in terms of sustainability performance. 

Changing objectives and building design 

Starting in the 1850's, based on Florence Nightingales' "Notes on Hospital", hospital wards were designed 

as large, open, well-lit facilities so that nurses could supervise a lot of patients [17]. As illustrated in 

Figure 4(a), the "chronic" objective at that time was nurse and staff efficiency. Nowadays, patient privacy 

and comfort are primary concerns and the "Nightingale" ward design has been replaced by a series of 

patient rooms (Figure 4 (b)) [18]. 

7/29 
 

 

 

 

 

 

 

 

 

a) source: http://www.flickr.com/photos/vculibraries/4269022763/, 

free to share and remix with the attribution of the work to Virginia 

Commonwealth University Libraries 

b) source: http://www.flickr.com/photos/usnavy/5913486058/, free 

to share and remix with the attribution of the work to Official U.S. 

Navy Imagery 

Figure 4 Examples of a) well lit facility ("Nightingale" ward) taken from: b) private patient room in a 

hospital 

Looking at these two configurations from a fire safety point of view, the following comments can be 

made: in an open patient ward, permanent staff, whose primary objective is to quickly attend an agitated 

patient, can detect a fire as soon as possible and may extinguish the fire before it spreads away from the 

1st burning item. In case the fire is not detected and controlled that quickly, smoke and fire may spread 

fast and evacuation of all ward patients becomes vital. In the private patient room configuration, fire 

detection would rely on automatic detection rather than detection by staff who are only briefly present in 

each patient room. An automatic suppression system could also prevent the patients in the room from 

being injured and a door closing upon fire detection could limit smoke and fire spread outside of the room 

of fire origin. This example clearly illustrates that the design of the building is highly dependent of its 

"chronic" objectives, which design has a strong impact on how the fire protection measures should be 

selected, installed and maintained as a whole as these measures both include managerial and technical 

measures, prevention and protection measures. More detailed "chronic" objectives related to hospitals can 

be found in [19]. 

Changing objectives and building usage 

Looking at turnover rates of building materials and their impact on the environment, Wærp and Holthe 

[20] notably conducted surveys and interviews of property managers and architects in Norway. The 

following paragraph is extracted from their 2009 paper: 

“The architects were asked which materials that are often replaced in buildings. This is dependent on 

type of building and year of construction of the building. In office building interior materials is often 

changed e.g. flooring materials, ceilings, interior walls and lightening are all changed within 5-15 

years. Buildings that are refurbished today are from 1970-80. Solutions and materials are in general 

poor. There are necessary to change ventilation. After 25 years you are left with façade (when quality 

is good), stairway and load bearing structure. In building from about 1900 more components are kept: 

e.g. doors, windows, ceilings, facades and often original interior materials. New buildings from today 

8/29 
 

 

 

 

 

 

 

 

 

will probably have better quality than in the 1970-80, but there will probably be frequently change in 

surface materials.” 

This information illustrates the fact that even if a building remains an office building during its whole 

lifespan, the nature and the amount of material (including combustible materials) as well as the exit 

pathways (interior separation may change or completely disappear with “open space” configurations) 

have to be reassessed periodically to verify that the performance of the system regarding fire safety has 

not decreased. It should be noted that building occupant demographics also evolve over long period of 

times, which may have a significant impact on emergency situations. For example, fire evacuation 

parameters such as walking speed and crowd density, established from experiments in the late 1980's, 

should take into consideration population obesity increase. Global ageing population should also be 

considered [21]. Now that we realized designs may not fulfill every objective defined by all groups 

involved in a building project, and that building usages, during the building lifespan, may not follow these 

objectives, the next part of this article concretely presents how this situation impacts the FPEs' analysis of 

fire protection measures. 

Impact of the original design assumptions on actual fire performance 

Knowledge of the "chronic" objectives is important when estimating (a) how long building occupants 

delay their evacuation after an alarm starts and (b) the state of the building, its systems and its fuel load as 

modified by users over the course of time. In the case of considering occupant delay times during a fire, 

the estimation of this "pre-movement" time is related to several factors, and particularly to two called 

"commitment" and "focus". In Figure 5, people seem quite focus on playing slot machines, inside a 

Japanese game center. The row of slot machines is itself designed to maximize occupancy time by a 

single person whom is provided with a chair, has repetitive actions to perform in a very focused vision 

range, with people in the near proximity, which make it very easy to lose track of time and difficult to be 

aware of anything happening in the surroundings. People are committed to go on playing as long as they 

have still money to feed the machines. The "chronic" objective of casinos, related to a high degree of 

focus and commitment, leads to an increase of the "pre-movement" time, and therefore competes with the 

life safety objectives to have all these people evacuate as soon as possible in case of emergency. 

Figure 5 Example of commitment in a Japanese game center (source: 

http://www.flickr.com/photos/davidooms/2964039286/, free to share and remix with the attribution of the 

work to David Ooms) 

9/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

From the perspective of the state of the building, its systems and its fuel load, maintenance of systems, 

fire safety management plans, changing of contents and furnishing, modifying compartmentation (adding 

or deleting doors, rendering safety measures inoperable), and many other factors can affect the size and 

spread of fire. Building regulations do not address many of these issues (e.g., contents are not regulated). 

As such, a ‘chronic’ building use may negate a fire safety measure (e.g., propping open a smoke door to 

facilitate unimpeded movement). Where building features are likely to be changed, or fuel loads added, 

or similar actions taken, such ‘chronic’ conditions should be considered at the design stage and factored 

into the design strategy. 

Impact of the actual building usages on the treatment of fire events 

It should be noted that in case of an emergency many building users have a strong tendency to try to leave 

via the route that they entered by rather than using the nearest emergency exit [26]. Displays in 

department stores and shopping malls are designed to make the potential buyer go from one stand or shop 

to another: the position of the displays, always changing, can also have some influence on the movement 

time as people need to find their way out. Estimation of egress paths would be much different when 

considering design floor layout empty of the movable booths and the real layouts during Sales periods 

(Figure 6). Besides, lots of additional "Clearance Sale" may also make it more difficult to locate Exit 

signs. In consequence, during Sales periods, the use of exits other than the one people used to enter the 

department store might be lower than in regular store usage. 

Figure 6 Example of a French department store display during sales (source: 

http://fr.wikipedia.org/wiki/Fichier:Ambience_de_solde.jpg, put into public domain by Wikimedia 

Commons User Medjaï) 

A building is dynamically defined with time. For example, the structure of a convention center remains 

the same in its lifespan but its interior configuration constantly changes as a function of the exhibitions 

proposed by the convention center owners. From a FPE perspective, nature, amount and location of fire 

loads are very different for a comic convention, boat show, sport event, etc. Distributions of attendee 

characteristics (e.g. age, gender) are also relevant and should therefore be gathered and their influences 

considered in the fire risk evaluation carried out by the FPE. 

10/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Fluctuations can also be seen in the characteristics of a mall concerning the population number and 

repartitions during the day (food court being more populated around meal times) and days of the week. 

Transitory combustibles can be located in the common areas (outside the mall shops) for more or less 

extensive periods of time (such as Christmas decorations in Figure 7). It is necessary to consider of all 

these fluctuations when assessing fire protection system performance (e.g., sprinkler efficiency and 

combustible control, for this shopping mall example). In the USA, the day following Thanksgiving 

(celebrated on the fourth Thursday of November) is becoming the first day of the period during which 

Christmas decorations are put in place. These decorations are removed in the beginning of January. Are 

these decorations transitory combustible when they are inside a mall for more than two months? 

Figure 7 Christmas tree located close to exit routes and main entrance of a shopping mall 

The internal structure of a building, designed according specific "chronic" objectives, influences how the 

building occupants would react in case of a disruptive event (casino example). Arrangement inside the 

structure of a building, also designed according specific "chronic" objectives, may decrease or negate the 

efficiency of measures which would help people mitigate the impact of disruptive events (example of 

department store during sales). 

Strong interconnections between people and building components 

Building occupants and building components may have strong interconnections: in a hospital, for 

example, people can be connected to life supporting machines, so fires impacting these machines (directly 

or indirectly) can affect the life safety of the people connected to them. Indirect effects of a fire on such 

patients could result from a fire damaging the distribution of electricity in the building, as well as the 

backup of this utility. 

Also in a hospital, a HVAC/filtration system provides air quality and control of microbe and odor 

migration between the different functional zones of the hospital. Scott [15] studied a smoldering fire that 

happened in a storage room in a hospital in New Zealand, in 2008. Smoke generated by this fire traveled 

via a HVAC duct from the storage room to an operating room. This situation can be qualified as a direct 

impact of the fire, because the fire effluents directly affect the safety of the patient and of the medical 

staff (even if the room where the fire was located was not the same room where the targets were located). 

Keeping the same configuration, the HVAC/filtration system provides microbe migration control by 

maintaining a pressure differential between different functional zones: this ΔP assures that microbes are 

not going from the examination room towards the operating rooms where people are more vulnerable to 

11/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

this threat. A fire damaging the HVAC system ability to maintain this ΔP would compromise the safety of 

the patients most vulnerable to infections. Thus, this last example also illustrates the indirect effects of a 

fire on targets. 

In healthcare facilities, the main safety targets are the patients. Losing a building component from a fire 

may affect patients. In other terms, the safety of the patient may depend on building components 

remaining fully functional. The opposite configuration also exists in some building occupancies: a most 

emblematic example is the nuclear power plant, where staff may be in relative danger in case of a fire but 

have to remain within the plant in order to maintain the nuclear core within a safety range. 

Proposed new treatment of disruptive events affecting the overall building performance 

The review of current PBFPD processes were found to be quite focused on the fire development itself, 

from ignition to extinguishment so that they ignore the recovery phase, which is essential to consider, as 

illustrated above by the Philips fire and the New Orleans warehouse consecutive fires. Because engineers 

dealing with complex disruptive events are too focused on the design of protective measures specific to 

their own event, they may consider that the integration of these measures is done at a higher level, by the 

design team who will ultimately synthesize how building users would use and maintain all these different 

measures. In other terms, the measures against each disruptive event are designed as independent building 

components and are supposed to be used and maintained by building users as originally designed, without 

considering competing objectives, minor usage changes and the fact that the building users may ignore or 

misuse these measures as they do not think every day about events that may or may not occur during the 

building lifespan. In order to solve these issues, a new treatment of disruptive events affecting the overall 

building performance is proposed, based on a systems approach. 

Introduction of the "building-occupant" system paradigm 

In many countries, building codes can be seen as the first official document providing a taxonomy for 

buildings. As an example for this paper, healthcare occupancies are examined through the US perspective. 

The International Building Code (IBC) established by the International Code Council (ICC) includes the 

Institutional Group (I-2) which gathers detoxification facilities, nursing homes, hospitals, and mental 

hospitals. Categorized in the same group, these different buildings do need the same requirements. In all 

these facilities, populations are vulnerable, unable to evacuate without assistance but they are very 

different and the building systems are also very different, as shown in Figure 8. A classification, such as 

the one established in ICC IBC, is a "good" start but still necessitates going in a deeper taxonomy level to 

clearly define a proper "building-occupant" system. 

Looking at other building classifications, it was found the one established by the US Bureau of Census 

[13] more useful than the ones in building codes in defining more precisely the "building-occupant" 

systems. In this taxonomy a distinction is made between child day care (with the code 624410), general 

hospitals (with the code 622110), psychiatric and substance abuse hospitals (with the code 62221) and 

nursing care facilities (with the code 62311). In addition to providing a better "building-occupant" system 

descriptor, a benefit of using this taxonomy is that the Bureau of Census periodically collects information 

concerning each of its categorical areas, which can be helpful in the performance assessment. 

12/29 
 

 

 

 

 

 

 

 

 

 

a) Child care facility, source: 

http://www.flickr.com/photos/shaggypaul/351385178/, 

free to share and remix with the attribution of the work 

to "Shaggy Paul" 

b) Hospital, source: 

http://www.flickr.com/photos/usnavy/ 

5913202904/sizes/o/in/photostream/, 

free to share and remix with the 

attribution of the work to Official 

U.S. Navy Imagery 

a) Nursing home, source: 

http://www.flickr.com/photos/13384589@N00/2780553 

606/, free to share and remix with the attribution of the 

work to by "Robinsan" 

Figure 8 Examples of facilities under the ICC IBC Institutional class (I2) 

Based on this taxonomy, we defined a "building-occupant" system as a system defined by a structure (i.e. 

building) inside which occupants are primarily engaged in a specific activity. This activity is quantified 

(e.g. activity number carried out by day or week) and then the performance of the system is estimated by 

the level of this activity. Occupants are defined as persons who are physically inside the system, 

independently of the duration of their stay. Building components are defined in our paradigm as physical 

portions of the system which can include, for example, spaces dedicated to a particular occupant activity 

of the system or in support of that activity (e.g. HVAC system). 

Introduction of the "functional zone" concept 

A hospital contains different areas which can be identified according to the functions they provide, such 

as reception areas, emergency rooms, examination rooms, operating rooms, patient rooms and intensive 

care units. Such areas which can be grouped by function are named "functional" zones, as they are created 

to fulfill the functions related to the daily objectives of the facility. In addition, there are utility systems 

and areas which provide support functions, such as power, heating, ventilation and air-conditioning 

(HVAC), throughout the facility. These utility systems can be located in "utility" zones (mechanical 

rooms, electrical rooms, cafeteria...) or throughout the building (such as the HVAC system). 

For example, Figure 9 illustrates the required level of detail for different functional zones of a hospital, 

describing the types of population in each of the zones. For example, people located in the reception area 

are future in-patients, visitors and staff and almost all of them are mobile and conscious. This is important 

as they would require no or little assistance in case of a hazardous disruptive event such as a fire. Inpatients located in emergency rooms or in operating rooms are undergoing surgery and are connected to 

life-supporting machines. This is important as extracting them during a fire would require following 

procedures and requiring time that may not be compatible with a rapidly growing fire [15]. In addition, 

while a utility zone supporting a reception area may be important to facilitate the comfort of the 

13/29 
 

 

 

 

 

 

 

 

 

occupants, a utility zone supporting an operating room functional zone is essential. If a fire occurs in the 

utility zone supporting a reception area the impact in the reception area could be limited to an 

‘inconvenient’ loss of power or lighting. If a fire occurs in the utility zone supporting the operating room, 

the impact could be life-threatening. 

Hospital 

Reception 

Examination rooms 

Emergency rooms 

Operating rooms 

Intensive care units 

Patient rooms 

Staff + in-patients (mostly mobile) + visitors 

Staff + in-patients (not mobile and mobile) 

Staff + in-patients (not mobile) 

Staff + in-patients (not mobile) 

In-patients (not mobile) 

In-patients (not mobile and mobile) + visitors 

Figure 9 People description according different functional zones of a hospital 

To summarize, characteristics of occupants within specific locations of a building, as well as the intended 

function of spaces in a building and contents in those spaces which are essential to achieving the required 

function needs to be clearly understood, identified and categorized. This constitutes essential information 

required by the fire protection engineer in order to address stakeholder objectives for "building-occupant" 

systems when elaborating a fire safety strategy. However, no current PBFPD process directs an FPE to 

examine a building at such a level of detail, explains the reasons why such a level of detail is important, 

or provides guidance how to approach the assessment. In large part this is because current PBFPD 

processes are focused too much on the fire event itself instead of being target-oriented, focusing on the 

objectives of concern within the specified functional zones or a well-defined "building-occupant" system. 

Key-concepts of "building-occupant" systems 

In order to summarize our "building-occupant" system paradigm, we have several key concepts: 

•	 Functional zones: spaces which are directly linked to the performance of the system (e.g. in hospitals, 

visiting areas where patients are checked in, patient rooms where patients are being prepared for 

surgery, operating rooms, intensive care units and patient rooms where patients recover before 

checking out); 

•	 Utility zones: spaces which indirectly contribute to the performance of the system, often providing 

support to the "functional zones" (e.g. storage rooms, electrical rooms, mechanical rooms); 

•	 Targets: key elements who’s performance is of concern within systems (the actors or users of the 

functional zones). For example, targets can be building occupants (patients including their visiting 

families and friends and staff in hospitals, pupils and teachers in schools) or building contents 

14/29 
 

 

 

 

 

(important piece of equipment required to contribute to the performance of the system such as a 

newly developed micro-chip in high tech industry or a priceless artifact in a museum); 

•	 Chronic states of the system: which represent the situations of the system while it is operating as 

designed or after each modification of its design (e.g. normal use of the system). 

•	 Chronic objectives: objectives the system is designed or subsequently modified, to attain during its 

chronic states; 

•	 Disruptive events: every possible event (technological events, natural events, socio-economical 

events) having an effect on the performance of the system. A disruptive event lasts between two 

chronic states of the system. 

•	 Acute objectives: objectives the system is designed or subsequently modified, to attain during 

disruptive events; 

•	 Event effects: damaging effects of a disruptive event on a target. These can be ‘direct effects’ or 

‘indirect effect.’ With respect to fire as a disruptive event, "direct effects" reflect fire-induced damage 

upon targets, such as heat, toxic, corrosive, irritant effects. "Indirect effects" reflect loss of building 

components which are vital for the targets to perform in the system. For example, a fire can through 

‘direct fire effects’ such as heat directly damage power cables to a life supporting equipment, which 

then has an indirect effect on the safety of people connected to this equipment. 

A new performance-based design process structured as a systems approach 

Within this "building-occupant" system paradigm, a risk-informed performance-based process was 

established, as illustrated in Figure 10. Its application is aimed to quantify the effects of any type of 

disruptive events affecting the overall performance of a specific system. 

Political 

Stakeholders’ 

decision 

Political 

Stakeholders’ 

project 

definition 

Technical steps of the overall system performance-based process 

Target 

vulnerability 

criteria 

estimation 

Disruptive 

event risk 

analysis 

(quantification 

of the impact) 

Cost-benefit 

analysis 

Disruptive event 

risk 

characterization 

Disruptive 

event risk 

analysis 

(quantification 

of the 

likelihood) 

Evaluation of 

the integration 

of the 

disruptive 

event 

protection 

measures in 

the system 

Figure 10 Political and technical steps of the system specific risk-informed performance-based process 

15/29 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

At the initial step of the process the stakeholders of a "building-occupant" system under consideration 

clearly indicate the nature and the characteristics of the system in terms of "chronic" objectives. This step 

is essential as it specifies the parameters of the "building-occupant" system to be examined in terms of 

building components, occupants and functional/support zones used by the system in order to achieve the 

"chronic" objectives. This initial step is also a "political" step of the risk-informed performance-based 

process as the system stakeholders need to come to an agreement on the system main goals and decide 

whether the system will possess specific building attributes such as an atrium or a high rise configuration, 

which are of special importance when dealing with fire risk for buildings containing these attributes. 

All the information gathered by the stakeholders is then transmitted to the engineer in charge of 

evaluating the impact of a certain type of disruptive event on the overall performance of the system: FPEs 

to deal with fires, structural engineers for earthquakes, etc. Since the system targets are the components 

which contribute to the overall performance of the "building-occupant" system, it is imperative that the 

stakeholders list in this step of the process all the system targets so that the engineer take them into 

consideration while performing the technical steps of the process. At this point, the corresponding 

engineer carries out the "technical" part of the process, which mainly consists of a target oriented risk 

analysis well integrated in a systems approach, by performing the steps as follows: 

•	 Selecting risk acceptance metrics that are representative of the considered system in relation to the 

stakeholders' listed targets during the chronic use of the building. The aim of the "risk 

characterization" step is to correlate the likelihood of the disruptive events which occur during 

chronic operation with vulnerability criteria for each of the listed target (e.g. assessing how often the 

disruptive event causes injuries or casualties when the target is the building occupant, based on 

statistics and past events) - Step 1; 

•	 Quantifying the vulnerability criteria for each target in case of the disruptive event (e.g. evaluating the 

mechanisms by which the disruptive event can have direct and indirect effects on each listed target 

while taking into consideration the capacity/incapacity of the target to absorb the damage from the 

disruptive event and still be functional/loses its functionality) - Step 2; 

•	 Carrying out a risk analysis of the direct and indirect effects of the disruptive event on the overall 

performance of the system, via the characterization of both the likelihood - Step 3 and the impact ­

Step 4 of the disruptive event on each of the listed targets; 

•	 Evaluating the integration of the protection measures against the disruptive event, analyzed in the risk 

analysis, so to verify that these measures, once installed, would not be ignored or misused by the 

system end users - Step 5; 

•	 Performing a cost-benefit analysis of the protection measures against the disruptive event, analyzed in 

the risk analysis - Step 6. 

At the end of the technical steps of the performance-based process, the engineer dealing with a certain 

type of disruptive event will transmit three important documents (or three components of a consolidated 

document) back to the system stakeholders: 

•	 One document containing the results of the disruptive event risk analysis (from technical Step 3 and 

Step 4) including a risk matrix or risk curves and explaining how the engineer's proposed protection 

measures reduce the risk of the disruptive event affecting the performance of the studied system, 

16/29 
 

 

 

 

 

 

 

 

 

 

 

•	 One document describing the possible interactions of the protection measures designed by the 

engineer against the disruptive event and the other components of the studied system, 

•	 One document estimating the costs and the benefits to install and maintain the proposed protection 

measures. 

Based on the results thus collected, the stakeholders finally decide on the set of protection measures they 

want to be installed in the system, knowing how well these protections would help the system to mitigate 

the impact of the disruptive events on the performance of the "building-occupant" system in its chronic 

state, how well these protections would be integrated in the system and how much they would cost to 

install and maintain. It was realized that the concerns related to building usages fluctuating according to 

building changes may be addressed by incorporating, into a performance-based process, a mechanism for 

not only looking at expected normal operations (chronic use) but for triggering reassessment if certain 

operational schemes are modified by building usages (using in Step 5 of the new process, a feedback loop 

as defined in a systems approach). In case the performance-based process is simultaneously conducted on 

several disruptive events, the different engineers involved in proposing protection measures against their 

respective disruptive events have to generate a common additional document since it is important to 

verify that all their additional protection measures are not counterproductive (Figure 11). It should be 

noted that the initial political step is identical for the stakeholders as they only need to provide once, in 

their own terms, the specifics of their "building-occupant" system. The "translation", in terms of solving 

the right problem for each disruptive event, is made by the corresponding engineer in the technical step 

related to risk characterization. 

Figure 11 Practical treatment of multiple disruptive events 

Conclusions 

Designing a building project is a complex enterprise involving project stakeholders who are the main 

drivers of the project concept and professional groups who are the main drivers of the actual realization of 

the project. In addition to this complexity, differences arise between the building project at its design 

phase and when the building is actually exploited by its end users. 

17/29 
 

 

 

 

 

 

 

 

 

 

 

 

The performance of a building depends on the interrelations between the different components of the 

building which are separately designed by specific engineers, having their own objectives to fulfill, so the 

final integration of all the building components may not be optimal. When these components concern 

disruptive events, i.e. events affecting the daily performance of the building such as fires, it was found 

that the end users might misuse or ignore the protection measures against the disruptive events, because 

these measures were not integrated well enough by the end users. 

This paper presented the outcomes of research carried out in order to: 

•	 define a paradigm of study organized around systems formed by specific building types and their 

associated occupants so to clearly determine how hazardous disruptive events such as fires affect 

these system daily performance, 

•	 introduce a corresponding system specific risk-informed performance-based design process, which 

could take into consideration the complexity of such systems and their evolution during disruptive 

events. 

Acknowledgments 

The authors would like to thank the US National Institute of Standards and Technology (NIST) for 

supporting the research on which this present paper is based, under grant 60NANB10D228. 

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eleventh edition, edited by R. Coté and G. E. Harrington, NFPA, pp.667-669. 

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Endnotes 

1 As soon as it received the call, Nokia started to work closely with Philips and other of its providers so to maintain 

its own production of mobile phones and satisfy its customers in a period of time when demand for this type of 

product was booming worldwide. Ericsson’s reaction was different: they treated the fire incident at the Philips plant 

as a "technical matter" which would result as a chip production disruption of one week only, which is something that 

could easily be taken care of. Unfortunately for Ericsson, the disruption lasted longer and by the time it realized the 

size of the disruption, it was too late and Ericsson failed to deliver mobile phones to its customers. 

As a result of the small fire that occurred in 2000 at the Philips Albuquerque plant, Philips's chip sale loss, estimated 

to a US$40 million, was almost covered by a 39 million Euro settlement with its insurance company; this loss only 

accounted for 0.6 percent of the US$ 6.8 billion semiconductor global benefits of Philips for 2000. Having failed to 

deliver its new generation of mobile phones, Ericsson reported losses between US $ 430 million and US $ 570 

million in the first disruption-affected quarter, due to a lack of parts, that is to say more than ten times Philips' 

losses. In addition to the fire disruption effects, incorrect product mix and marketing problems are to be blamed for 

Ericsson's US $ 2.34 billion losses in the mobile phone division by the end of 2000. This situation led to a SonyEricsson merging for designing, producing and marketing mobile phones, in April 2001. In addition to its competitor 

economic situation, Nokia's fire disruption treatment helped to increase its percentage of the mobile phone market. 

2 Speeding up activities in hazardous environments have shown dramatic results. 

20/29 
Annex D
 

A Simple Probabilistic Fire Safety Risk Model for Room and Corridor
 

Configurations in Different Building Uses
 
A Simple Probabilistic Fire Safety Risk Model for
 

Room and Corridor Configurations in Different
 

Building Uses
 

Cornelius Albrecht and Brian Meacham∗

Abstract: Performance-based codes and fire safety design methods are in use worldwide. However, most performance building codes lack quantitative risk, safety or performance criteria, and the decision regarding acceptance criteria often rests with the 

fire protection engineer and design team, with no benchmarking against other buildings. As a result, there is a high degree of variability in fire engineered building design 

solutions and in the review and approval of these solutions, and therefore in the levels 

of fire safety provided in buildings that have been designed using performance methods. Although there have been no significant fire-related failures that can be attributed 

to “unacceptable” fire safety performance being delivered under the current system, 

performance failures in other regulated areas, perceived quality concerns, and a desire 

to be more transparent has motivated several countries to try and better understand 

and quantify the level of fire safety and performance being provided in deemed-tosatisfy solutions (acceptable solutions, approved documents) and to establish quantitative measures for use in next generation performance-based building codes. 

To help facilitate progress on quantifying the level of fire risk, safety and performance in buildings, and the development of data, tools and methods for risk-informed 

performance-based design, research has been conducted in these areas under Award 

60NANB10D228 from the U.S. National Institute of Standards and Technology (NIST). 

In this work, a simple probabilistic risk analysis model, using Monte Carlo and event 

tree analyses techniques, is developed for room and corridor geometries to assess life 

safety levels based on different occupant and fire protection system characteristics. The 

development of model is briefly described along with the input parameters and the simplifications made. The model runs 100,000 simulations for each fire scenario, giving a 

good impression of the annual failure probabilities of the fire life safety design in such 

buildings. In addition, the assumed probabilities for the various decision gates within 

the event-tree are analyzed for their impact on the system reliability using a simplified sensitivity analysis. To quantify the impact of the various fire protection systems 

assumed, analyses with and without these systems are performed. Furthermore, an 

occupancy-specific analysis with respective variation of the input parameters provides 

a comparison between different building uses for a similar geometry. The results are 

analyzed, discussed and recommendations for future performance-based fire life safety 

codes are made. 

∗Department of Fire Protection Engineering, Worcester Polytechnic Institute, Worcester MA, USA 

1
 
1 Introduction 

The model developed herein is in accordance with the quantitative risk assessment studies on the 

140 Williams Street building conducted by Thomas et al. [25] and incorporates elements from the 

study by Olsson [21] and Frantzich [10, 11]. The stochastic model for the various times herein was 

also adapted from the above sources and was validated with deterministic state-of-the-art numerical 

fire protection engineering tools, namely computational fluid dynamics (CFD) and microscopic 

egress simulations. The deterministic evaluations were found the be in the range of the input 

parameter distributions, so that the validity of the model is given. 

The probabilities for the fire ignition, spread, and the barrier probabilities are varied in a parameter 

study to quantify their sensitivity with regards to the overall failure probability. The results are 

visualized in a so-called tornado diagram. In addition, comparative analyses are conducted where 

the fire protection systems, assumed to be installed and operational with their respective failure 

probability, are compared to a case without the respective system installed in order to quantify the 

impact of those systems. 

Based on the results, the most sensitive parameters are derived for various building occupancies in 

order to allow for a quantitative comparison of the fire risk. This could lead to a more risk-informed 

design since it directly incorporates occupancy-specific input data and thus provides the basis for a 

future code framework. 

2 Model description 

The model utilized herein in a simple event-tree based simulation model similar to the models 

used by Thomas et al. [25] or Olsson [21] that utilizes crude Monte Carlo simulation [17] in order to compute failure probabilities for the various scenarios. The system analysis is subsequently 

performed using simplified event-tree analysis in order to compute the overall annual failure probabilities of in-room and corridor fires for a standard office-type fire compartment geometry. The 

models along with the input parameters are discussed in the following. 

2.1 In-room modeling 

The in-room model computes the failure probability of a successful self-rescue from the room of 

fire origin based on a simple comparison of the available time until untenable conditions are reached 

(ASET) and the total required time to respond to a fire cue and subsequent egress into the corridor 

(RSET). The egress is obviously successful if ASET is greater than RSET and the failure domain 

is defined 

Ωf = ASET ≤ RSET. (1) 

Probabilistic analysis with n = 100,000 simulations is performed for each scenario with crude 

Monte Carlo analysis where random numbers are drawn from the stochastic model for ASET and 

2
 
RSET. The failure probability pf can then simply computed by dividing the number of failed simulations by the total number of simulations 

∑n

i I(Ωf )i 

pf = , (2)

n 

with I(Ωf ) being an indicator function that either yields 0 for successful or 1 for failed simulations. 

For the event-tree model, it was assumed that the annual ignition frequency for fire in standard type 

buildings can be assumed to be around pig. = 1E −2 [8, 9]. The probability for the fire develop into 

a severe and hostile fire was assumed to be 20% according to Thomas et al. [25]. This is similar 

to the numbers given in, for example [4, 20]. For the fire to threaten the occupants, the room of 

fire ignition has to be occupied, which was assumed to be the case in 80% of the time. In case of a 

hostile fire, the time to untenability (ASET) can be assumed to be between 4 and 10 minutes. This 

is assumed to be uniform distributed in accordance with the assumptions made in the analysis of 

the 140 William St building [25]. A deterministic CFD simulation for a room of similar proportions 

using commonly chosen input source terms yielded untenability within this range. This is also in 

accordance with various fire tests conducted [18, 24, 15, 7, 14]. 

The effect of a sprinkler system for the room of fire origin was omitted since the system will most 

likely actuate when untenable conditions are reached or are about to be reached. Nevertheless, he 

sprinkler will be considered in the corridor spread model. 

As for the RSET, three different scenarios were considered: the first scenario assumes a fast manual 

detection of the fire by the occupants within the development phase by visual, auditory or olfactory 

means. This is considered to occur with a probability of 70%. The detection time is rather fast 

since the occupant is in the same room as the fire. In accordance with [25], the times to perceive 

the fire cue is uniform distributed between 0 and 2 minutes. In addition, a response time has 

to be considered which includes an attempt to extinguish the fire and the escape from the room. 

Since the rooms are comparatively small, a uniform distribution between 0 and 2 minutes was 

assumed. A brief deterministic numerical simulation and self-conducted tests showed these times 

to be reasonable assumptions. 

In a second scenario is is assumed that the occupant in the room will not manually detect the fire 

(the remaining 30%). It is assumed that a smoke detection system is installed that will detect the 

fire and alarm the occupant with a success probability of 85%. This number includes various subscenarios, i.e. for example the failure of the system to detect the fire, the occupants ignoring or 

overhearing the alarm and even the incapacitation of the occupants before the alarm. The time for 

the detection system to detect the fire and alarm the occupant is given with a uniform distribution 

between 3 and 15 minutes. Since the alarm occurs at a later time during the fire development 

and will make the occupants aware of the danger faster, the reaction time is modeled here as a 

uniform distribution between 0.1 and 0.5 minutes (immediate escape from the small room after the 

alarm). 

In both of the above scenarios, n samples will be drawn from the distributions and ASETi and 

RSETi (= ∑Δtj) will be compared for success or failure of each case i. 

3
 
Sc. 1 

Man. detection 

Sc. 2 Occ.present 

Auto. detect. Fire devel. 

Sc. 3 Fire init. 

no hazard 

Figure 1: Event-tree of the in-room model. 

The third scenario considered in this in-room model is the failure of the manual and the automatic 

detection, leading to a certain fatal outcome, so that the scenario failure probability is 100%. Looking at the event-tree, the probability of this scenario to occur is fortunately very low. 

All the scenarios can be compiled into an event-tree tree with each branch representing one of the 

above scenarios. The probabilities can then be computed by multiplying each branch horizontally 

under the assumption that the decision gates are not correlated [16]. This leads to individual annual 

failure probabilities for each scenario as shown in figure 1. In order to compute the overall annual 

failure probability of the event tree, the annual scenario probabilities pi can be summed up as 

a simplification, since each scenarios occurrence is purely stochastic and thus it implies a series 

system. Hence, the simplification [16] can be made to 

pf ,sys. ≤ 1 −∏(1 − pi) ≈ ∑pi. (3) 

The overall annual failure probability for the event-tree was computed to pf ,sys. = 3.54E −4. 

2.2 Corridor modeling 

The corridor model is similar to the in-room model, but more complex due to the advanced stage 

of the fire and more possible scenarios. In order for the fire to spread to the corridor, further 

probabilities have to be introduced to the system. As mentioned above, if a sprinkler system is 

installed, it will not have any effect on the tenability in the room of fire origin, but it will have a 

large effect on the fire spread. It is assumed that a successful sprinkler actuation will control the 

fire and confine it to the room of origin, so that no fire spread will occur. The sprinkler system is 

assumed to be successful in 98% of the cases, in accordance with the numbers given in [8, 9]. This 

number includes not only the failure of the system to actuate, but also the failure of controlling 

the fire and hence it was chosen lower than the assumed probability of 99.9999% for the system to 

control the fire given the sprinkler system works, which was comprehensively derived in Thomas 

et al. [25]. 

The probability of the fire to spread beyond the room of origin is given in Thomas et al. [25] with 

90% if the door to the room of origin is open. The times for the fire to spread are modeled with a 

uniform distribution between 0 and 20 minutes after reaching untenable conditions in the room of 

4
 
origin. For the analysis herein it was additionally assumed that fire spread can also occur when the 

door is closed with a probability of 60%. Thomas et al. [25] even assume the spread probability 

with a closed door to be 85%. An in-depth analysis of the sensitivity of the various probabilities 

assumed herein in given in section 3. The time for the fire to spread given a closed door are modeled 

with a uniform distribution between 20 and 40 minutes according to the original model. 

After having spread with the according spread probability and time distribution it will take some 

time for the more voluminous corridor to develop untenable conditions. This is assumed to be 

uniform distributed between 5 and 20 minutes after the fire has spread. Untenability in the corridor 

herein was assumed to preclude safe egress from all the other rooms so that the occupants therein 

are in immediate danger. 

In order for the fire spreading into the corridor to be detected manually, occupants must be present 

in the corridor, which is assumed to be less likely then in the rooms and thus was chosen to be 

only 30%. Given that occupants are present, the same probabilities and times for manual detection 

were assumed as for the in-room model. If no occupants are present in the corridor, the occupants 

in the other rooms must rely on the detection system, which has the same probability and time 

properties as for the in-room model above. Should the detection system fail also, it is assumed that 

this scenarios leads to the entrapment of the occupants in their room since they will not become 

aware of the fire until untenability in the corridor prevents them from a safe egress (RSET = ∞) 

with a scenario probability of 100%. It should be noted here, that this not necessarily means for 

fatalities to happen, since the occupants could defend in place in their rooms until they are rescued 

by the fire department. More in-depths models for the fire spread and fire department responses are 

given in [25, 12, 26]. 

The above assumptions can also be structured and systematically assessed with an event tree which 

would lead to six scenarios after the fire develops in a room and the sprinkler is not able to contain 

it: 

1. door closed, people present , manual detection successful, 

2. door closed, people not present, auto detection successful, 

3. door closed, people not present, auto detection fail (worst case 1), 

4. door open, people present, manual detection successful, 

5. door open, people not present, auto detection successful, 

6. door open, people not present, auto detection fail (worst case 2), 

The time spans Δt for ASET were sampled n times and compared to the sum of the time spans 

for RSET in a crude Monte Carlo simulation in order to produce the scenarios failure probabilities 

for the above scenarios 1,2 and 4,5. The worst case scenarios are assumed to have a 100% failure 

probability given their occurrence as mentioned above. 

The overall annual system failure probability for the corridor becoming untenable before the safe 

egress from the other rooms is completed was calculated to be pf ,sys. = 1.57E − 05, which is 

approximately times 20 lower than the in-room failure probability. Hypothesizing that the common 

definition of risk (R) as the sum of all scenario probabilities (P) multiplied with their respective 

5
 
effect (E) The overall annual system failure probability for the corridor becoming untenable before 

the safe egress from the other rooms is completed was calculated to be pf ,sys. = 1.57E −05, which is 

approximately times 20 lower than the in-room failure probability. Hypothesizing that the common 

definition of risk (R) as the sum of all scenario probabilities (P) multiplied with their respective 

effect (E) 

R = ∑Pi ·Ei (4) 

applies herein, it could be, for example, recommended based on this outcome that no more than 

20 units/rooms shall be located within a protected fire compartment in order to keep the risk constant. 

3 Parameter study and system sensitivity analysis 

While the time spans used above are chosen and modeled as distributions to account for uncertainty 

within the data, the assumed probabilities for the fire protection systems, the fire spread, etc. are 

chosen based on available data, experience and educated best practice guesses. Being probability 

data, there is no obvious way to validate the data, especially since comprehensive fire statistics are 

still missing. In the following a sensitivity analysis is conducted to gain insight into the overall 

system behavior should some of the assumed values be too optimistic. Also, a sensitivity analysis 

shows the most critical components of the system and thus it is easier to detect missing redundancies and short-cuts that could potentially jeopardize the life safety concept. 

For the analyses herein, a simple approach was chosen to identify the effect of one parameter on 

the system performance [6]. In this approach, a reasonable range was chosen for each probability. 

While holding all other parameters fixed at their original value, the system is evaluated at the 

minimum and the maximum value of the chosen range. The resulting system probability range 

is plotted as a probability band. This analysis is repeated for every parameter. Subsequently, the 

resulting bands will be sorted by the size of their interval producing the so-called tornado plot in 

figure 2 showing the parameters in order of their sensitivity. The input and resulting intervals are 

shown in table 1. 

Obviously, the fire ignition frequency and the probability of a full fire to develop have the highest 

sensitivities within the system for both, the in-room and the corridor risk assessment. This can 

be attributed to the early stage within the event tree and the ultimate nature1 of these decision 

gates. Without ignition or fire development, respectively, there cannot be a hazard situation for 

the occupants. This is rather unfortunate, since these parameters are those which can not or only 

slightly be influenced and very little information is known about the accuracy of these numbers, 

since only a few comprehensive fire statistics exist in the literature, for example [13]. 

For the in-room case, the highest sensitivities to the input ranges can be seen for the manual detection followed by the probability of occupants being present. While the latter can be attributed 

to the ultimate gate nature within the event tree, the manual detection has such a strong influence 

on the overall probability, since the detection can occur very early during the fire development (0-2 

1A decision gate that directly leads to failure or safety without any further elements within the regarded branch of the 

event-tree is considered an “ultimate” gate herein. 

6
 
Table 1: System sensitivity analysis and results. The component probabilities are given in percent, 

the system failure probabilities in absolute numbers. 

Component In-room Corridor
 

org. [%] min [%] max [%] min max min max 

Fire ignition 1 0.0445† 10 1.58E-5 1.80E-3 6.94E-7 7.78E-5 

Fire development 20 10 50 1.77E-4 1.10E-3 7.83E-6 4.7E-5 

Occupants in room 80 60 99 2.66E-4 4.38E-4 – – 

Manual detection 70 30 90 8.28E-4 1.18E-4 1.57E-5 1.56E-5 

Automatic detection 85 75 99 3.69E-4 3.33E-4 1.65E-5 1.43E-5 

Sprinkler success 98 90 99.9999 – – 7.81E-5 7.81E-10 

Occupants in corridor 30 10 60 – – 2.00-5 8.89E-6 

Door open 80 20 90 – – 1.10E-5 1.63E-5 

Spread via closed door 60 20 70 – – 1.54E-5 1.56E-5 

Spread via open door 90 75 99 – – 1.42E-5 1.65E-5 

†Thomas et al. [25] state an ignition frequency of 8.9E-6/m2/year. A unit size of 50 m2 is assumed herein. 

Annual system failure probability 

0.00E+00 5.00E-04 1.00E-03 1.50E-03 2.00E-03 

Fire init. 

Fire devel. 

Man. Detec. 

Occ. pres. 

Auto. Detec. 

3.54E-4 

Figure 2: Tornado sensitivity diagram for the in-room model. 

7
 
Annual system failure probability
 

0.00E+00 2.00E-05 4.00E-05 6.00E-05 8.00E-05 

Sprinkler 

Fire init. 

Fire devel. 

Occ. in corr. 

Door open 

Auto. Detec. 

Spread open door 

Spread closed door 

Man. Detec. 

1.57E-5 

Figure 3: Tornado sensitivity diagram for the corridor model. 

minutes after ignition). The automatic detection will actuate later within the fire course between 

3 and 15 minutes while the tenability limit can already be reached after 4 minutes. This essentially means, that if the fire is manually detected the occupants are always able to escape, making 

the manual detection an ultimate decision gate, whereas the automatic detection is not. Changing 

automatic detection time to an earlier time span would significantly increase its sensitivity, as an 

additional Monte Carlo simulation of the system showed. 

For the corridor model, the highest sensitivity (along with the aforementioned ignition frequency 

and fire development) can be seen for the sprinkler system as shown in figure 3. While not playing a 

significant role within the room of fire ignition due to the comparatively late actuation with respect 

to the time to the development of untenable conditions [1], it can be seen here, that the sprinkler is 

ea strong barrier for the fire spread beyond the room of origin and for the structural fire protection 

[9, 3]. This is also amplified by the modeling herein, where the sprinkler acts as an ultimate gate 

and a successful containment will not endanger any occupants in adjacent room. This, of course, 

could and should be investigated in more detail in further studies with numerical tools, such as 

proposed by Albrecht [4, 1]. 

Furthermore, the presence of occupants in the corridor and the state of the door (open/close) has 

some impact. Occurring later within the event tree, the fire spread probabilities only have a minor 

impact on the system reliability.The manual detection is directly dependent on the presence of 

occupants in the corridor and, therefore, the influence on the system is only minor. 

8
 
Table 2: Quantification of the impact of fire protection systems.
 

System
 

Baseline (all systems) 3.54E-4 1.57E-5 100 100 

No Sprinkler 3.54E-4 6.40E-4 100 2 

No auto. detection 4.80E-4 2.35E-5 74 67 

No Fire doors 3.54E-4 1.75E-5 100 90 

None 4.80E-4 1.30E-3 74 1 

Pf ,sys Normalized [%] 

In-room Corridor In-room Corridor 

4 Influence of fire protection systems 

For all the examples above, including the sensitivity analysis, it was assumed that all the fire protection systems considered were operational with a certain probability of failure. The impact might 

be larger for this analysis than what was found in the previous section since the probability bounds 

in table 1 are rather narrow for some of the systems. For example, the lowest sprinkler reliability 

was chosen to be 90% which is still more favorable than the complete absence of such a system. 

In order to assess the overall quantitative impact of a fire protection system, probabilistic analysis 

have to be performed for the system not being present. This can be easily modeled by setting 

the failure probability to 100%, or the reliability to 0%, respectively, implying that the system 

will always fail and thus is disregarded within the system analysis. The resulting system failure 

probability for the in-room and the corridor model can then be compared to the case in with the 

system is present with its assumed failure probability as described in section 2. 

For the analysis herein, the following three systems were analyzed and compared to the above base 

case: sprinkler, automatic fire detection system, and fire doors. The results are shown in table 2. In 

addition, the system is analyzed with none of the fire protection systems present. The right-most 

columns for in-room and corridor are normalized against base case (100%) and show the percentage 

of remaining safety in comparison to the base case which has all systems present and operational 

with their respective failure probability from section 2. 

The results again show the strong influence of the sprinkler system which can be, as mentioned 

above, attributed to the ultimate gate nature within the model. Other than that, the fire door have 

a marginal influence. This rather slight influence might be due to the fact that the original model 

above already accounted for open doors in 90% of the cases. The automatic detection system was 

identified to be the only system that has an impact within the room of fire origin. While this a due 

to the modeling it implicitly shows that most systems target directly at the fire spread, which is in 

accordance with the code objectives in, for example NFPA 101 [19, Section 4.11] that primarily 

requires protection for “occupants not intimate with the initial fire development”. 

For further analysis, the interaction between fire protection system could be analyzed as well as 

the influence of the various systems on the various occupancies shown in the next section in order 

to determine which system is most favorable for which occupancy. This could also contribute to a 

more risk-informed and performance-based allocation of assets for fire protection, which currently 

are as high as 10% of the total building cost [23]. 

9
 
5 Occupancy-specific risk analysis 

Based on the findings above and incorporating the results of the sensitivity analysis, further studies 

can be conducted considering occupancy-specific input data in order to compare the emanating 

risks directly. For the analysis herein, the following occupancies were analyzed considering the 

same or a very similar underlying building geometry with multiple units connected with a corridor 

within a fire compartment: 

Office occupancy considers the occupants to be awake and familiar with the surroundings as well 

as capable of self-egress within a comparatively short time frame. Since this was the data 

used for the original analysis herein, it constitutes the baseline case. 

Residential occupancy is very similar to the office occupancy with the difference that the occupants might be asleep and thus the manual detection probability is reduced. In addition, 

the manual detection and response times are chosen to be slightly longer than for the office 

occupancy. 

Hotel occupancy accounts for the occupants to be generally asleep and unfamiliar with the surroundings. Yet, general capability of self-egress after a prolonged pre-movement time (depending on the fire cue or alarm received) can be assumed. 

Educational/School occupancy assumes that the teachers and students are awake and familiar 

with the surroundings but are subjected to higher stress and thus potentially irrational behavior during a fire emergency. Regular fire drills can improve the egress performance. It 

is generally assumed that the occupants are capable of self-egress (younger children possibly with the teacher’s assistance), but might require additional time, which can be reflected 

within the RSET model. 

Hospital/Nursing occupancy has the occupants most likely to be bed-ridden without the capability 

of self-egress. Horizontal evacuation with the assistance of the attending personnel can be 

assumed, but would most likely take a very long period of time. In addition, no means or data 

to model this situation are know to the author, so that for simplicity it is assumed herein that 

RSET = ∞ for this occupancy so that the failure probability is solely based on the probability 

of fire spread2. 

The models chosen for the occupancy-specific values for RSET, herein the manual detection times 

and the response time after a manual and automatic detection, respectively, are assumed to be 

uniform distributed (for the lack of better models) with the parameters shown in table 3. 

While it can be assumed that at least some of the input probabilities, such as presence of occupants, doors open/closed, etc. will differ among the various occupancies, the sensitivity analysis in 

section 3 showed that their impact on the overall safety is rather low so that their variation was omitted. The only exception is the manual detection in the in-room model, which–for the lack of better 

2Enhanced models could consider a defend-in-place scenario, where the spread from the corridor or the room of 

origin into another room could be analyzed with the respective structural barriers (another door or wall rating, etc.) 

and ultimately the fire departments capability to control the fire before the spread as it is proposed by Thomas et 

al. [25] 

10
 
Table 3: Occupancy-specific stochastic models (in minutes) for manual detection and response time 

to manual and automatic detection, annual fire ignition frequency, and manual detection 

probability for an in-room fire. 

Man. detec. Resp. m/a Ign. prob. P(m det) Pf ,sys.

Occupancy Min. Max. Min. Max. [per annum] [%] In-room Corridor 

Office‡ 0 2 0/0.1 2/0.5 0.01 70 0.000354 1.57E-5 

Residential 0.5 2.5 0.5/0.1 2.5/1 0.03 50 0.0018 3.99E-5 

Hotel 2 5 1/0.1 6/4 0.037 20 0.0046 6.12E-5 

Educational 1 4 3/1.5 5/4 0.04 50 0.0042 7.27E-5 

Hospital – – ∞/∞ ∞/∞ 0.3 0 0.0048 1.05E-4 

‡ This is also the baseline scenario for the analyses above. 

data–has to be assumed for each occupancy herein and are shown in table 3. The highly sensitive 

fire ignition probabilities are also given in table 3 which is based on the findings by Rahikainen 

and Keski-Rahkonen [22] and the data given in BS 7974 [8] and the German Eurocode Annex [9]. 

It should be noted, that the data has a large variability of up to one magnitude depending on the 

reference used. 

The results based on the data used herein show that various occupancies can be simply assessed 

by using their respective annual fire ignition frequency and some simple, but reasonable assumptions about the occupants’ response by variation of the stochastic model. For the analysis herein, 

the occupancy was only considered based on the RSET, while more complex models could also 

incorporate different models for the ASET. Nevertheless, the results show that all the occupancies 

produce results within the same order of magnitude with the exception of the office-occupancy 

which, besides having the most favorable parameter constellation, also has a comparatively low 

annual ignition frequency. 

The other outlier is the risk beyond the room of ignition for the hospital occupancy. This can 

obviously be attributed to the model assumption, but also shows the vulnerability of occupants 

without the means of self-escape. This should definitely be considered in additional requirements 

(i.e. sprinkler systems, compartmentalization, fire rating of walls and doors) if a defend-in-place 

strategy is chosen. 

6 Summary and conclusions 

The study within this report showed the capability of a rather simple model in order to show the 

annual reliability levels of standard-type buildings with a rather straight-forward geometry. Such 

buildings would currently only be regraded with prescriptive codes, since performance-based fire 

protection engineering is usually only applied to complex and voluminous buildings that require 

special attention due to shortcomings to the current codes. Within this study, a simplified Monte 

Carlo and event-tree-based model was developed that is able to compute approximate probabilistic 

safety levels for the room of fire origin and the adjacent rooms within a fire compartment. While the 

assumptions are rather simple, they could be easily amended with more complex models using an 

11
 
approach as outlined in [20, 2] oder even CFD-based risk analysis [5]. This would allow for a more 

in-depth understanding of the underlying processes and it would allow risk-informed, performancebased occupancy-specific source term values for the fire effects and input parameters for the egress 

modeling, as outlined by Albrecht [1]. 

Varying the probabilities of various decision gates within the system not only shows their impact 

on the system reliability, but unveils potential weak points within the system design. In addition, it 

shows which fire protection systems have a large impact and which do not. In the example above 

it was clearly shown that a sprinkler system might not have a significant impact on the tenability 

within the room of fire origin, but it significantly mitigates the hazard emanating form fire spread 

beyond the room of origin. 

Furthermore, cases with and without the respective fire protection systems showed the quantitative 

impact of the systems with respect to the in-room and the corridor model. It was shown that 

especially the sprinkler system herein has a significant impact due to the modeling as an ultimate 

gate for the fire spread. While the systems only have a slight impact on the safety within the room of 

fire origin, a large influence can be seen for the corridor model. In further analyses, the underlying 

models, especially for fire spread, could be refined in order to derive more accurate results. 

An occupancy-specific analysis yielded some information of the fire risk with respect to the occupancy. While it was difficult to find accurate data, especially for the fire ignition frequencies, 

some general conclusions can be drawn which are coherent with state-of-the-art risk assessment 

techniques. The event-tree-based approach shown herein can provide a basis for the future structuring of risk-informed and performance-based life safety codes by providing a systematic and 

quantitative basis for occupancy-specific risk assessment. 

In further analyses, it is anticipated to significantly improve the data basis along with a more suitable stochastic model. The hard-bounded uniform distributions should be replaced with better 

models that also account for (physically reasonable) values beyond these bounds. In other studies 

by the author, normal, log-normal, or extreme value distributions were used with the appropriate 

caution with respect to the physical limits. 

Acknowledgments 

This study was conducted during a post-doctoral fellowship at the Department of Fire Protection Engineering at Worcester Polytechnic Institute (WPI) under the supervision of Prof. Brian 

Meacham. The work was generously supported by the National Institute of Standards and Technologies (NIST) under the grant “Characterization of Risk and Quantification of Design Fires” 

(Award 60NANB10D228). 

12
 
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14
 
Annex E
 

Risk-Informed and Performance-Based Life Safety Design in Atrium-Type
 

Buildings
 
Risk-informed and performance-based life safety design in

atrium-type buildings 

Cornelius Albrecht1 and Brian Meacham2
 

1Simpson, Gumpertz and Heger, New York, NY, USA
 

2Dept. of Fire Protection Engineering, Worcester Polytechnic Institute, Worcester, MA, USA
 

ABSTRACT 

Performance-based fire protection design is often applied, where a traditional, prescriptive design 

is not feasible or is cost-prohibitive. However, the relative risk of the performance-based option is 

often not compared with the relative risk of the prescriptive solution. In this paper, a risk-informed 

approach based on probabilistic risk analysis is shown in order to quantify the risk emanating from 

various possible fire scenarios. In order to handle the high computational costs for the proposed 

analyses, a cloud computing-based non-linear response surface method is employed which enables 

the utilization of state-of-the-art numerical fire engineering tools, such as computational fluid dynamics (CFD) and complex egress simulation. The probability of failure of the scenarios as well 

as other considerations will be assessed in order to derive conclusions and recommendations for a 

more risk-informed and thus ultimately cost-optimized fire protection design. 

1 INTRODUCTION 

With modern, open architecture and a general movement towards an optimized and performancebased building design, the traditional approach to fire protection with prescriptive requirements and 

compartmentalization specifications is not applicable in many cases. Instead, numerical simulation 

of the fire and smoke propagation, occupant egress behavior and structural response is conducted in 

order to tailor a cost-benefit optimized fire safety concept for the particular building. In order to get 

these alternative, performance-based design options approved by the authorities having jurisdiction 

(AHJs), usually a proof of equivalency to the existing, prescriptive fire codes is required, which 

constitute a “deemed-to-satisfy” solution, i.e. they are considered safe by definition. 

Currently, this proof of equivalency can only be shown qualitatively, for example for life safety 

by showing that the time of a fire to develop untenable conditions within the compartment of 

interest (available safe egress time, ASET) is longer than the time for the occupants to safely 

escape from that compartment (required safe egress time, RSET). Input parameters, fire scenarios, 

threshold values, etc. within this analysis are chosen by the fire protection designer and are agreed 

upon with the AHJs. In order to provide some form of implicit safety, these values are chosen 

to be deterministic and conservative, whereas an analysis of the uncertainty is usuallz omitted. 

Additionally, rather arbitrary safety factors (κ) between 1.5 and 3.0 [1–6] are used, so that 

ASET ≥

!

κ · RSET (1) 
� �

� �

�

�

in order to prove that a life safety design is safe. Obviously, ASET and RSET are highly dependent of the deterministic input parameters, scenarios, etc. chosen, so that different fire protection 

designers will ultimately have different solutions [7]. This uncertainty is even amplified if Eq. 1 is 

regarded as pass-fail option without looking at the margin of safety Δt between ASET and RSET 

[8]. 

2 PROBABILISTIC TREATMENT 

To address these shortcomings of the current analysis process, the input parameters (xi) which can 

be, for example, the maximum heat release rate (HRRmax), fire growth rate, number of occupants, 

pre-movement times, etc., can be assumed uncertain. Probabilistic analysis can be conducted in 

order to quantify the probability of a proposed design solution to fail (pf ), i.e. ASET ≤ RSET, so 

that under cosideration of Eq. 1 

pf ≡ P r(Ωf ) = P r(ASET(x1...j ) − RSET(xk...n) ≤ 0) (2) 

where Ωf is the so-called failure domain of the limit state. The uncertain parameters (xi) can be 

considered to follow statistical distributions, and can (and should) be defined using available data 

and statistics. 

In order to solve Eq. 2 and to compute pf , the resulting joint distribution function f(x) of all 

variables xi has to be integrated over Ωf , so that Eq. 2 can be solved 

pf = · · · f(x)dx. (3) 

Ωf

Despite this straightforward formulation it can be impossible to analytically find f(x), since the 

evaluation of Eq. 2 required the utilization of numerical models, such as CFD and egress simulation 

tools. A common and robust method to solve the problem is the Monte Carlo simulation [9–11], 

which constitutes a numerical integration scheme. Herein, Eq. 3 is reformulated to 

pf = · · · I(Ωf ) · f(x)dx, (4) 

x

where I(Ωf ) is a so-called indicator function1. This formulation from Eq. 4 can be discretized for 

computational implementation to 

1 n

pˆf = I(Ωf )i, (5) 

n

i=1

1 1 if ∈ Ωf I(Ωf ) = 0 if ∈/ Ωf
where n is a finite number of independent simulations. In order to achieve accurate results, a large 

number n of simulations have to be performed, since n → ∞ yields exact results due to the law of 

large numbers [12]. The big drawback of this method is obviously the high numerical costs, that 

are implied within the numerous required simulation runs. 

2.1 Response surface approach 

In order to reduce the numerical cost, an adaptive response surface method using a varianceoptimized Monte Carlo simulation was developed [13] which bypasses the high number of required simulations runs by replacing them with an approximative mathematical formulation that 

can be exploited at low numerical costs. The fitting of the surrogate or response surface model 

only requires a limited number of support points (i.e. actual simulation runs). To maximize the 

accuracy of fit of the surrogate models, the traditional approach using linear least-square regression models [14] was replaced with a moving least square formulation [15]. For an interpolative fit 

at the support points, the weighting function was chosen accordingly as outlined in [13, 16]. The 

methodology is described in detail in [17] and thus is not reproduced in details here. 

2.2 Load distribution with cloud-based on-demand IaaS-HTC systems 

Despite the reduction of required simulation runs, still a rather significant numerical workload 

has to be dealt with, especially when it comes to analyses where multiple scenarios or complex 

geometries have to be evaluated. This workload can even exceed the computational resources that 

are available locally or would be too time-consuming if processed sequentially. For that reason, an 

cloud-computing interface was developed that uses the Infrastructure as a Service (IaaS) service 

model [18] in order to build on-demand high throughput computing (HTC) systems [19] in the 

Amazon Elastic Compute Cloud [20]. This is particularly applicable, as the various simulations 

are non-interacting and thus the problem can be deemed “embarrassingly parallel” [21] and can 

be distributed to loosely coupled computing instances. The computing instances are added and 

removed dynamically depending on the current workload and/or availability. This has the sideeffect of optimized resource utilization which is an ultimate driver for the cost-effectiveness. In 

previous studies, it was shown by the author that a 250 core HTC system could be build within 

30 minutes [20], while other sources allegedly even built systems up to 50,000 cores [22]. 

Such scalable systems or even hybrid systems to extend the local in-house capacities with cloudinstances could provide sufficient computational resources at reasonable cost for most problems 

in fire protection engineering, even beyond the scope of probabilistic risk analysis. Other potential 

areas of application along with more details on the methodology developed can be found in [20]. 

3 SCENARIOS AND PARAMETERS FOR AN ATRIUM-TYPE GEOMETRY 

In order to demonstrate the applicability of the developed methodology for generic examples beyond the scope of rather small geometries such as in [13,17], an atrium-type building was chosen 
Fig. 1. The numerical model of the atrium geometry used within this work. 

as depicted in Fig. 1. This type of building is usually subject to performance-based fire protection 

design since prescriptive fire codes are usually not sufficiently detailed or not applicable altogether 

[1]. Atria can be used for various purposes and thus occupancy and fire risk can differ significantly 

throughout even the course of one year. This will be accounted for within the various fire scenarios 

considered. 

3.1 Building description and analysis objectives 

The atrium shown in Fig. 1 is a generic example of an entrance to a medium-size office building 

and is supposed to create a welcoming and representative first impression to the occupants. The 

atrium contains space for a centrally located product display and a reception area for visitors. 

Offices are located on all levels (1-3) and are connected to the atrium or in corridors off the atrium. 

The corridors are separated from the atrium space with smoke-tight doors which automatically 

close upon actuation of the fire detection system and thus were deemed omissible within the fire 

simulation but will be considered within the egress analysis. Emergency stairs exist at the ends of 

each corridor, yet the offices are usually accessed through the atrium and the free stairs (and an 

elevator) within the atrium. 

The main objective of the analysis is showing a safe egress case of a fire within the atrium. Despite 

the additional emergency stairs, it has to be assumed that a significant number of occupants will 

try to escape the building through the atrium since it constitutes the primary means of egress. Additionally, it has to be considered that the atrium can be used for special high-occupancy occasions 

such as receptions or seasonal events. This will be included in the risk analysis. 
Table 1. Stochastic model for the “standard” scenario.
 

Parameter Unit Distribution Mean Std.-Dev. Cov.-Var. 

HRRmax MW Normal 4 0.8 20 % 

tg s Gumbel (min) 250 30 12 % 

yCO g/g Normal 0.090 0.030 33 % 

yHCN g/g Normal 0.006 0.002 33 % 

ySoot g/g Normal 0.120 0.040 33 % 

3.2 Fire and egress scenarios 

Three fire scenarios were identified to be of particular interest within the context of quantitative risk 

analysis, namely a “standard” fire which is based on the t-squared fire [23] with a linear incubation 

phase [24], a fire in the reception desk area based on the NIST kiosk fire tests [25], and a Christmas 

tree fire centrally located within the atrium, based on DHS fire tests [26]. 

3.3 Standard fire scenario 

The “standard” fire scenario is analyzed herein, because it is based on the t-squared fire growth 

which is a common and generally accepted approach for the quantification of fire scenarios. The 

fire is assumed to increase the HRR quadratic over time until a maximum HRR is reached. The 

growth rate is usually given as the time tg in seconds until 1 MW is reached or as α in kW/s2, 

respectively. Based on the findings in [24] and looking the HRR courses of various fire tests [27], 

a linear phase of tg seconds was added in order to account for a fire incubation phase. The same 

scenario was also used in [17, 28] and thus yields a quantitative comparison between the atrium 

and the assembly building. The fire is placed centrally within the atrium, implying some form of 

product display (e.g. show car display). The stochastic model for the source terms was also adopted 

from the sources above and is given in Tab. 1. 

3.4 Kiosk 

In order to create a occupancy-specific scenario for the atrium space, a fire was assumed to develop 

within the reception area. The fire was assumed to behave similar to the NIST kiosk fire tests [25], 

and hence the stochastic model was developed based on the results of those tests. To conservatively envelop the fire, a t-squared fire with linear incubation was chosen (s. above and fig. 2). The 

uncertain fire source term parameters along with their distributions are shown in Tab. 2. 
Table 2. Stochastic model for the kiosk scenario.
 

Parameter Unit Distribution Mean Std.-Dev. Cov.-Var. 

HRRmax MW Normal 1.645 0.2 12 % 

tg s Gumbel (min) 400 100 25 % 

yCO g/g Normal 0.050 0.0125 25 % 

yHCN g/g Normal 0.003 0.0008 27 % 

ySoot g/g Normal 0.100 0.030 30 % 

Fig. 2. Conservative derivation of the kiosk scenario. The red line shows the course of the 

enveloping mean scenario according to tab. 2. Not to scale. Adopted from [25]. 

3.5 Christmas tree 

A third fire scenario of particular interest was an ultra-fast developing fire. Therefore, a fire of 

a large Christmas tree was assumed, which is placed in the atrium during the holiday season. 

In order to quantify the scenario, the Christmas tree fire data from the DHS [26] was used and 

extrapolated to a larger tree that would be assumed in the atrium. One of the main risks emanating 

from Christmas trees is the extremely fast fire growth to high maximum HRRs. In order to account 

for this in a conservative manner, a t-squared fire spread without incubation was assumed. Since the 

tree will burn out very quickly, approximately 70 % of the fire load is assumed to be consumed after 

only 150 seconds and thereafter the fire will decay linearly and will burn out after 200 seconds. 

These assumptions are approximately coherent with the experimental data [26]. The uncertain 

parameters and their stochastic model for the reliability analysis is given in Tab. 3. 
Table 3. Stochastic model for the Christmas tree scenario.
 

Parameter Unit Distribution Mean Std.-Dev. Cov.-Var. 

HRRmax MW Normal 3.05 1.3 43 % 

tg s Gumbel (min) 40 16.3 41 % 

yCO g/g Normal 0.005 0.001 20 % 

yHCN g/g Normal 0.001 0.0003 30 % 

ySoot g/g Normal 0.02 0.002 10 % 

Table 4. Stochastic model for the egress scenario.
 

Parameter Unit Distribution Mean Std.-Dev. Cov.-Var. 

Warning time s Normal 60 15 25 % 

Pre-move. time s Gumbel (max) 90/180 25/45 28/25 % 

Occ. density occ./m2 Gumbel (max) 1.5 0.5 33 % 

Velocity m/s Normal 1.25 0.3 24 % 

3.6 Egress scenario 

The egress scenario analyzed herein is a high-occupancy scenario. It is assumed that the atrium 

is used to host a reception or gathering for, for example, a seasonal event. Hence, the atrium is 

assumed to have an occupant density usually found in assembly buildings. The balconies of the 

atrium are also highly occupied, whereas the office tracts (adjacent corridors and offices) have a 

normal office specific occupancy. The occupants are assumed to be both, unfamiliar and familiar 

with the building, as they could be guests/costumers and employees. Hence, around 70% of the 

occupants will try to exit the atrium through the main entrance. The stochastic models for both 

scenarios are given in tab. 4. 

This scenario can be deemed rather conservative, since such an occupancy will realistically only 

occur infrequently. Yet, for the purpose of this study, it sufficiently envelopes all possible scenarios 

on the safe side. For further analyses, also a normal occupancy should be analyzed in order to 

assess the average safety levels. This could also be integrated in a multi-step system approach, 

where fire and egress scenarios can be linked according to their respective probability. 

4 PROBABILISTIC ANALYSIS 

The probabilistic analyses were conducted using the methodology described above with the stochastic models for the defined scenarios. In addition to the probabilities of a safe evacuation to fail pf , 

sensitivities αi can be derived for the input parameters in order to quantify the influence on the 

limit state variance. 

While RSET is defined as the point in time when the last occupant reached a point of relative 

safety (i.e. left the atrium through the main exist or evacuated into an emergency stairwell), the 

definition of ASET largely depends on the threshold criterion chosen. Herein, two criteria were 
considered: a rather conservative momentary visibility criterion expressed by an optical density of 

0.15/m, which approximately corresponds to a visibility of 20 m [29, 30], and a time-cumulative 

fractional effective dose model [31,32] which considers asphyxiant fire effluents and heat (radiation 

and convection). For FED, values of 1.0 and 0.3 were chosen to determine untenability. The data 

required to determine ASET was recorded at every floor at 2 m above the floor level. This allows 

for a more detailed analysis on a floor-by-floor basis and to incorporate local phenomena, such 

as balcony spill plumes, etc. Additionally, the simulations were evaluated for smoke detector and 

sprinkler actuation times in order to develop appropriate stochastic models for future use. 

4.1 Standard scenario 

A first analysis for the standard scenario with the visibility threshold yielded a failure probability pf

of 98.5%. While this number is extremely high, this can be assumed extremely conservative since 

the comparison of ASET and RSET is based on under-running the visibility threshold at the third 

floor to the last person existing to a relative place of safety at a very high occupancy. In reality, 

the third floor balconies could be evacuated via the stairs and the adjacent corridors before the 

visibility threshold is reached. Occupants coming from the office tracts trying to evacuate through 

the atrium would be likely to turn around once they see the smoke when approaching the atrium. 

The closing of the smoke-proof doors between office corridors and atrium adds an additional safety 

margin for safe egress via the emergency stairs. 

Looking at the sensitivities, the fire growth time to 1 MW tg, the pre-movement time and the 

number of occupants have the highest sensitivities, with αtg = 0.57, αpre = −0.58, and α#occ =

−0.58, respectively. In total, these three parameters can explain 99% of the overall variance. 

The same analysis with the FED values as threshold to determine ASET yielded the following 

results: none of the (support point) simulations returned a FED-value of 1.0 within the simulated 

time frame of 20 minutes, in which the egress was completed. Therefore, it can be assumed that 

for the chosen fire scenario, a FED of less than 1.0 can be defended-in-place. For a FED threshold 

of 0.3 which is sometimes conservatively used to account for vulnerable parts of the population 

[1,3] yielded a pf of only 5.44%, whereas the mean safety margin between ASET and RSET was 

411 s (> 6 min). 

For the latter FED analysis, the sensitivities for the most relevant parameters were αtg = 0.87, 

αpre = −0.37, and α#occ = −0.31, respectively. In this case, the fire growth is the most relevant 

parameter, explaining 75% of the variability. All three parameters combined explain 98% of the 

variance. 

A comparative analysis was performed where the threshold times for ASET with the visibility criterion were only determined for the first and second floor (at 2 m above floor level) while assuming 

that people will rather quickly move to the corridors or the lower levels at fire start2. Again, this 

time was compared to the conservative RSET that the left occupant left the compartment. In this 

approach, the failure probability pf significantly reduced from 98.5% to only 6.36%, a more than 

factor 15 increase of the safety. 

2The last occupant leaving the third floor balcony was at a mean of 30 s. 
Obviously, the findings are due to the smoke-filling of the atrium, but is shows clearly that unreasonable assumptions (i.e. upper floor threshold vs. last person out of entire atrium) lead to biased 

numbers that do not reflect the actual level of safety within the compartment. An additional, yet 

deterministic analysis of the critical scenario identified (third floor visibility vs. evacuation from 

the third floor balconies) with conservative input parameters above showed that a safe egress will 

be possible. 

As for the simulated fire protection systems, the smoke detectors (located centrally on the ceiling 

of the atrium) actuated at a mean of 49 s, while the sprinklers above the fire and within the plume 

actuated at around 600 s. As found in previous studies [17] sprinkler actuation can be directly 

correlated to the fire growth (tg) with an R2 of greater than 99%. 

4.2 Kiosk fire scenario 

While the standard scenario gives a good estimate of the safety level of a rather conservative scenario, the kiosk fire was chosen to have a occupancy-specific scenario. The thresholds for visibility 

and FED were assessed in the same manner as stated above in order to retain comparability. The 

probability of the visibility criterion to be under-run on the third floor before the last occupant has 

exited the fire compartment was calculated to be pf = 43%. While still being rather high, within 

this scenario, the probability of failure is only half as high as it was for the standard scenario due 

to the less conservative, but more occupancy-specific parameter set. 

The highest sensitivities were, again, found for tg (αtg = 0.76), the pre-movement time (αpre =

−0.46) and the number of occupants (α#occ = −0.43), accounting for more than 97% of the variance, while tg is the dominating parameter accounting for about 57% of the variance. 

Looking at the FED criterion in order to determine the conservative ultimate threshold, again none 

of the support point simulations yielded FED values of 1.0 for the simulated 20 minutes. Contrary 

to the standard scenarios, also none of the simulation reached a reduced FED value of 0.3. The 

maximum values found for the FED when using high percentiles of the input distributions were 

around 0.15 at at a height of 2 m above the third floor level. Hence, further analyses with even 

more conservative FED values were omitted herein as the number of occupants and warming/premovement times are already assumed to be on the conservative side. Hence, for this scenario and 

set of input parameters the atrium can be assumed to provide a sufficient level of life safety. 

The mean time to smoke detector actuation was 124 s. This is due to the prolonged linear incubation phase with a low HRR at fire start. Also due the location of the fire partially underneath the 

balconies, the smoke has a longer travel distance and greater potential for dispersion before reaching the detectors. The sprinklers in the atrium ceiling did not activate during the simulated time of 

20 minutes. This is most likely due to the fact that the fire is not powerful enough and the resulting balcony spill plume does not produce sufficient temperatures to actuate the system. Additional 

detectors and/or sprinkler underneath the balconies will most likely actuate significantly earlier so 

that the systems would be more effective. Unfortunately, this was omitted during the setup of the 

simulation model. 
This scenario based on the NIST kiosk fire is more specific for the anticipated occupancy of the 

atrium, but it is less conservative when it comes to the severity of the impact. Since performancebased design is also targeted at providing the most cost-effective design, the specific selection of 

scenarios (in addition of prescribed scenarios from the codes) should be an essential part of the 

engineering analysis. 

4.3 Christmas tree fire 

While this scenario is less severe when it comes to effluent production rates (see Tab. 3), it is an 

extremely fast developing fire without any incubation phase, so it could potentially over-run the 

protection systems. In addition to the fast fire growth, a comparably high peak HRR of the tree is 

reached rather early during the course of the fire. This is reflected in the results for the visibility 

threshold which yielded a failure probability pf of more than 99%, implying that the visibility 

criterion will almost always be reached (2 m above the third floor balcony) before the last occupant 

has left the atrium compartment. Yet it should be noted, that at the same time as the 0.15/m optical 

density threshold was nearly always reached, the highest values of the optical density from the 

support point simulations were around 0.25/m for the high percentile input parameter sets. Since 

these values imply a visibility of around 4-5 m, it should not be seen as critical. In addition, since 

the fire load of the Christmas tree is consumed rather fast with the fire ending after around four 

minutes, a subsequent increase of the visibility can be expected as well. 

This can also be seen for the FED analysis, which is a time-integrated criterion as stated above. 

Herein, the maximum FED values reached in the support point simulation were only around 0.1, 

denoting that occupants on the third floor might me affected by the fast developing fire, but are 

unlikely to be severely harmed or even incapacitated. In addition, the warning and pre-movement 

times were conservatively not reduced for this scenario, but it is highly likely that the occupants 

would begin the egress when a certain fire cue is recognized (i.e. a fire size that is deemed threatening, etc.). 

As for the fire protection systems, the smoke detectors would actuate with a mean of 23 s, while 

the sprinklers either actuated within a maximum of 120 s of fire start or the fire did not generate 

enough heat to actuate the sprinkler at all. This highly depended on the input parameter set of the 

support point simulation and the maximum HRR can be directly correlated to the actuation state 

as well as the time in case of actuation. 

Despite the fast fire development and the severity of this scenario, the atrium can be deemed safe 

under the premise that, for severe scenarios, it should be allowed to expose the occupants to small 

amounts of smoke that barely affect but never prevents safe egress entirely [33, 34]. Yet, this is 

currently usually not the case in nearly all legislations or fire-specific codes. For that reason, a 

more hierarchical approach would be highly desirable. 

4.4 System analysis 

Even though the calculated failure probabilities are partially rather high, they have to be regarded 

in the context of the safety levels of other safety concepts, for example the structural Eurocode 
safety concept [35], where the requirements are stated in terms of acceptable failure probabilities. 

Those failure probabilities are referenced for a one-year-period. Since a hostile building fire is not 

a permanent, but an exceptional event, the fire frequency has to be taken into account. According 

to [36,37] and in analogy to [13], the annual frequency of a fire could be chosen to be, for example, 

pf i = 2E−2/y which is then multiplied with pf . In the perspective of annual failure probabilities, 

the numbers can then be compared to other annual probabilities or annual reliability requirements. 

Additional information on system analysis within a probabilistic analysis can be found in other 

publications by the authors. 

5 SUMMARY, CONCLUSIONS & OUTLOOK 

The preliminary results of the probabilistic analyses showed a broad variety of results, yet some 

general conclusions can be drawn. Besides the known fact, that the selection of the scenarios and 

input parameters is absolutely crucial for the design process, the analyses clearly showed that 

the fire growth rate tg, the pre-movement time, and the number of occupants are the most crucial 

parameters for the life safety process when t-squared or modified t-squared fire development curves 

are assumed [17]. Knowing about these parameters and their implications allows fire protection 

engineers to focus on the choice of the relevant inputs. 

In addition to the scenarios and parameters, the choice of the threshold criteria is also an important step in the design process. While there are obvious differences between momentary visibility 

criteria like the optical density and the time-integrated dose models like FED, the choice of the 

“correct” threshold values might not be as obvious. Using the traditional pass/fail approach to determine ASET potentially leads to a bias, as it can be seen above for the Christmas tree scenario: 

even though the threshold of around 20 m visibility will be under-run in 99% of the cases, visibilities of less than around 4-5 m are not expected either. The choice of only one criterion therefore 

could lead to overly conservative or too optimistic solutions. 

Besides these considerations, a more structured approach should be undertaken as to where (location, height, etc.) and how (criterion, model, etc.) to assess the tenability in order to define ASET. 

The same applies to the determination of RSET from the egress simulation, which is usually simply defined as the last occupant leaving the simulated compartment. In the applied example herein, 

the last occupant will exit the atrium through the main exit door at the ground level of the atrium, 

while the criteria are reached at the third floor balconies. A comparison of these particular values 

implies a margin of safety which completely remains unquantified despite the probabilistic efforts 

herein. 

Compared to the quantified example from [13], it is obvious that the results are in same range 

of magnitude and especially the parameters with the highest sensitivities proved to be the same. 

This is a significant first step towards the development of a safety concept that is based on a more 

risk-informed approach by looking at a quantitative metric, i.e. the failure probabilities of a life 

safety design in case of fire, instead of using (only) qualitative educated guesses and engineering 

assumptions. 
Also, further analysis should be performed by the fire engineer when it comes to the utilization of 

the classical ASET/RSET approach. In addition to the remarks in [8], in such analysis it is crucial 

to structure how exactly ASET and RSET are determined. This could include, but is not limited to, 

a possible multi-step approach, i.e. for the atrium this could be the analysis of local performance 

on the third floor and an additional analysis of the entire atrium and/or, for example, an in-depth 

analysis of the underlying uncertainties and minimum/maximum values of the threshold criteria 

instead of the current pass/fail approach. 

Linking the various fire and egress scenarios with a corresponding performance criterion could 

also yield some further knowledge about the total risk to life safety. For example, worst case fire 

scenarios can be linked with less severe egress scenarios and vice versa considering the probability 

of each scenario to occur. 

Conservative criteria such as the FED could, in addition, be linked to more severe scenarios, so that 

the validation is similar to the “ultimate limit” states within the structural codes [38], while less 

severe scenarios should be analyzed with, for example, visibility criteria, constituting an equivalent 

to the “serviceability limits” in structural codes. Thus, the solution would be reasonable and not 

overly conservative, but the worst-case scenario would still be considered in the analysis process. 

5.1 Recommendations for a risk-informed, performance-based life safety design framework 

Figure 3 shows the various elements of a proposed risk-informed and performance-based life safety 

concept. Within the framework of such a concept, various elements would have to be defined. 

These elements can be categorized into basic elements and performance elements. While the former include basic requirements and definitions, validation problems for the numerical models, and 

a hierarchy that regulates the models and the required competencies of the designers, the latter are 

more focused on the performance part, including, but not limited to, threshold criteria and their 

treatment, a (semi-) probabilistic safety concept and/or at least an uncertainty assessment framework, and concise specifications for modeling, input data, and effects of fire protection systems. 

As stated in [17], a safety concept could be anticipated that uses semi-probabilistic partial safety 

factors γi which are based on the respective sensitivities αi for the most relevant input parameters 

derived above. The partial safety factors could, in analogy to the Eurocode approach [35], be calculated considering their input distribution and their 90-percentiles, so that for a normal distributed 

parameter 

1 + αi · Φ−1(pf,req.) · Vi

γi = , (6) 1 + 1.28 · Vi

where αi is the sensitivity and Vi the variance of the underlying normal distributed parameter, 

Φ−1(·) is the inverse normal distribution, and pf,req. is the acceptable failure probability. Equation 6 

has to be changed to account for other distributions accordingly [39]. 
This, in conjunction with acceptable safety levels in a form of reliability requirements pf,req. embedded within a framework would lead to a more comprehensive and objective, and thus riskinformed and performance-based life safety design that replaces the traditional “black box”-approach 

when it comes to achieved safety. 

Fig. 3. Various aspects and elements of a framework for a more comprehensive risk-informed and 

performance-based life safety code. 

ACKNOWLEDGEMENTS 

This work was supported by a fellowship within the Postdoc-Program of the German Academic 

Exchange Service (DAAD) and grant #219810 from the US National Institute of Standards and 

Technology (NIST). 

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Annex F 

HRR_Catalog: Database on Heat Release Rates of Real Products 
 

The Vulcan Initiative 

Step 5: Fire Risk Analysis (Impact) 

Fire Effects Tool Databases 

HRR_Catalog: Database on Heat Release Rates of Real Products
 

Rev. 0
 

Alberto Alvarez Rodriguez and Manuel Hurtado
 

AON Fire Protection Engineering
 

4 Overlook Point, Lincolnshire, IL 60069 (USA)
 

Brian J. Meacham
 

Department of Fire Protection Engineering
 

Worcester Polytechnic Institute, Worcester, MA 01609 (USA)
 

June 28, 2014
 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

How to use the “HRR_catalog” spreadsheet
 

The “HRR_catalog” has been established to be a free repository of information about one of the major 

components of Fire Protection Engineering: the Heat Release Rate (HRR). One of the main sources of 

HRR consists of the eponym chapter by Vytenis Babrauskas in the SFPE Handbook of Fire Protection 

Engineering (Section 3, Chapter 1 for the 4th edition). The “HRR_catalog” objective is to collect heat 

release rates of “real products” or items that could be considered in an engineering analysis requiring fire 

modeling. Thus, the “HRR_catalog” contains HRR evolution with time (called “HRR curves”) of 

mattresses and wardrobes or of office worker cubicles that could be used to assess the consequences of a 

fire in a hotel guestroom or an office open space, respectively. 

The origin of the “HRR_catalog” came after noticing that even if the aforementioned source is unmatched 

in terms of contents (as it includes real products alphabetically ranging from beddings to windows made 

of plastics), its printed format could be improved in the era of information technology. For instance, 

publication restrictions of the SFPE Handbook generate updates every few years (3rd edition: 2002, 

4th edition: 2008) and it is not practicable to devote hundreds of pages on this particular but essential topic 

in a single book covering all the aspects of fire protection engineering. 

As a consequence, it was thought that providing information on the Internet would remove these 

restrictions in terms of space and content update. Attempts were made and webpages can be found but, 

unfortunately, instead of expanding the paper format, these webpages condensed even more the 

information presented in the SFPE Handbook under the form of tables. Besides, these attempts were 

proposed by individuals who could not maintain or update their webpages. 

Within the Vulcan Initiative, participants would have the opportunity to help implementing a database or 

catalog for heat release rates. A more pragmatic approach than a webpage configuration has been taken so 

that the information would not be contained (and therefore restricted) to the limits of webpage 

visualization but expended, as needed in separated and self-supported files. 

By its own nature, the heat release rate data is graphic and consists of the evolution of the HRR with time. 

Other information related to the test performed to obtain the HRR data can be associated with parameters 

such as the nature of the test, time to the maximum HRR or if additional measurements were made during 

the test (soot, CO...). As a consequence, it was decided to use a Microsoft Excel spreadsheet to gather all 

the information regarding heat release rates of real products. Excel presents the advantage to be relatively 

easy to use, widely known in Academia and work environment and with the latest version, it is possible to 

share the same document “on the Cloud” so that a single document is used and can be updated by 

multiple participants of the Vulcan Initiative. 

This present document explains the organization of the contents of the “HRR_catalog” spreadsheet, and 

then how a participant to the Vulcan Initiative can help implementing it for the benefits of the Fire 

Protection Engineering community. 

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1. “HRR_catalog” spreadsheet Overview 

The “HRR_catalog” information for each “real product” is located in two different sheets: 

•	 the “Overview” sheet (1st sheet, at the left of the sheet tabs) which serves as a table of contents. 

Each collected item in the Overview sheet will have a unique item number that is hyperlinked to 

the following sheet. 

•	 the “item” sheet which contains all the detailed information of the test conducted to obtain the 

heat release rate curve of the corresponding item. 

2. Instructions on how to create a new “Item” sheet 

The “HRR_catalog” will open at the “Item template” sheet, presented in Figure 1. 

Tab Section 

Figure 1. View of the “Item template” sheet of the “HRR_catalog” spreadsheet 

In the “tab” section at the bottom left of the Excel window, the following sheets would appear, from Left 

to Right: 

•	 The “Overview Template” sheet, 

•	 The “item Template” sheet, 

•	 “Items” sheets, named with a specific number, in decreasing order. In Figure 1, the HRR_catalog 

only contains 4 items. 

The first task is to “copy” the “Item template” and rename it with the Item number immediately at the 

right of the “Item Template” sheet, incremented of “1”. 

•	 Right click on the “Item Template” Tab, 

•	 Select “Move or Copy” in the menu, and in the corresponding window, select the number 

immediately below “Item Template” (it should be the highest number in the list), 

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•	 The sheet “Item Template (2)” is created. It needs to be immediately renamed with the Item 

number immediately at its right, incremented of “1” (In our case, “5”). 

You are now ready to fill up a new “item”. 

3. Instructions on how to fill up a new “Item” sheet 

You start a new “Item” sheet with a sheet identical to the one presented in Figure 2. 

Figure 2. View of the different parts of an “Item” sheet newly created (here “5”) of the “HRR_catalog” spreadsheet 

and ready to be filled up by a participant 

The “Item” sheet is composed of four parts: 

•	 Parameters of the “Item” which do not only include data about the tested item and the test 

measurements but also the “item” management, which is an important part of the peer review 

process required by the management of the Vulcan Initiative, 

•	 Columns of values so that the participant can describe the evolution with time of the heat release 

rate, 

•	 The corresponding graph of the HRR curve, 

•	 Additional notes about the test and comments from the participant about the test. 

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3.1. Filling up the “Item” parameter part 

Table 1 (in 5 parts a) to e) ) explains all the parameters, as well as gives some examples of acceptable and 

unacceptable inputs. 

Table 1. Content description of the “Item” parameter part 

Parameter Parameter Explanation Acceptable Inputs Unacceptable Inputs 

"HRR_catalog" management 

Item Number Sequential order from the last 

Item Number. See Section 2 to 

see how an item number is 

attributed 

Integers 

Participant Name of the participant filling 

up the new “Item” sheet 

Participant Affiliation Affiliation of the participant 

filling up the new “Item” 

sheet 

Participant Input Date Date of the “Item” sheet 

completion and submittal to 

the Vulcan Initiative 

dd/mm/yyyy 

(day, month, year) 

Peer Review Participant Name of the peer-reviewer 

checking the “Item” sheet 

Peer Reviewer Affiliation Affiliation of peer-reviewer 

checking the “Item” sheet 

Peer review date Date of the completion of the 

“Item” sheet peer review 

dd/mm/yyyy 

(day, month, year) 

a) "HRR_catalog" management Parameters 

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Parameter Parameter Explanation Acceptable Inputs Unacceptable Inputs 

Item Data 

Reference Reference the source using 

APA (American 

Psychological Association) 

format. Examples of the APA 

format are provided below this 

table. 

The authors and title of 

the source should be 

provided at a minimum. 

URL links to 

websites, authors 

only, title only. 

Item Category Category characterizing the 

group of the tested item Furniture 

Specimen Common name of the tested 

item 

Chair, couch 

Do not use the name 

of the item from the 

reference (“Chair 

F21” does not 

describe an 

upholstered armchair 

and “Chair F31” 

does not describe a 

loveseat. 

Primary Material The largest construction 

component. 

Descriptive words such 

as wood, cotton, 

polyester 

Vague words such as 

“blends,” “several” 

Secondary Material The second largest 

construction component 

Descriptive words such 

as wood, cotton, 

polyester 

Vague words such as 

“blends,” “several.” 

Mass (kg) Mass of the test specimen in 

kilograms 

Mass of the combustible 

portion of the specimen if 

possible. Comments 

under “Additional Notes” 

should be made if a 

significant portion of the 

mass is not combustible. 

-

Dimensions (m) Dimensions in meters 

describing the specimen in a 

simplified fashion 

Shapes such as cubes, 

cuboids, cones, and 

cylinders should be 

described as a simplified 

representation of the 

specimen. 

Single dimensions 

b) Item Data Parameters 

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Parameter Parameter Explanation Acceptable Inputs Unacceptable Inputs 

Test Data 

Test type Standardized test or method 

used to measure the heat 

release rate 

Furniture Calorimeter or 

internationally 

recognized standards 

such as ISO, ASTM, EN, 

UL and Factory Mutual 

This cell should not 

be left blank. 

Date of the test The date of the test is useful to 

indicate how relevant the test 

could be in regards to the 

evolution with time of the 

item. 

The year seems the most 

appropriate input as any 

more precise date does 

not really matter. 

Burner Type / Ignition 

Source 

The method of ignition and/or 

burner 

Typically a cigarette, 

sand burners, irradiance 

is used to ignite and/or 

maintain the fire. Notes 

should be made if the 

ignition source or burner 

contributes significantly 

to the measured heat 

release rate 

-

Test Duration (s) The time of the test from 

beginning to end. This time 

does not necessarily mean the 

specimen was consumed. It 

might mean that the test was 

stopped at the point. 

-

c) Test Data Parameters 

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Parameter Parameter Explanation Acceptable Inputs Unacceptable Inputs 

Test Results 

Max HRR (kW) Value of the peak heat release 

rate measured during the test. 

This value gives an indication 

of the order of magnitude of 

the item HRR. 

Integers (in kW) -

Time to Max HRR (s) Time to maximum heat 

release rate Integers (in s) 

d) Test Results Parameters 

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Parameter Parameter Explanation Acceptable Inputs Unacceptable Inputs 

Additional Results 

Mass Loss (kg/s) Mass loss during the test. It is preferred to have the 

mass loss in kg/s but it is 

also acceptable to have 

the mass at the beginning 

and at the end if that is all 

the information that was 

provided. 

-

Heat of Combustion (MJ/kg) Heat of combustion. Verify 

that the units are in entered in 

MJ/kg 

- -

CO Measurement Carbon Monoxide Both the value and the 

units must both be 

entered as shown in the 

filled out example if the 

measurement was taken 

during the test. 

The value alone is 

not sufficient. 

CO2 Measurement Carbon Dioxide Both the value and the 

units must both be 

entered as shown in the 

filled out example if the 

measurement was taken 

during the test. 

The value alone is 

not sufficient. 

Soot Measurement Solid carbon that burns at 

approximately 4000 °K 

Both the value and the 

units must both be 

entered as shown in the 

filled out example if the 

measurement was taken 

during the test. 

The value alone is 

not sufficient. 

HCl Measurement Hydrogen Chloride Both the value and the 

units must both be 

entered as shown in the 

filled out example if the 

measurement was taken 

during the test. 

The value alone is 

not sufficient. 

HCN Measurement Hydrogen cyanide Both the value and the 

units must both be 

entered as shown in the 

filled out example if the 

measurement was taken 

during the test. 

The value alone is 

not sufficient. 

HBr Measurement Hydrogen Bromide Both the value and the 

units must both be 

entered as shown in the 

filled out example if the 

measurement was taken 

during the test. 

The value alone is 

not sufficient. 

e) Additional Test Results Parameters 

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For these results, two Excel cells have to be filled up: the first one indicates the value of the measurement 

and the second one the unit in [ ] and the specification of the measurement. For example, during a test, a 

measure of the CO yield was established at the peak of the Heat Release Rate and it was 0.05. Thus, the 

“Item” cells would be filled as follows: 

CO Measurement: 0.05 [-] CO yield at peak HRR 

CO Measurement: 57 [ppm] CO volume fraction at peak HRR 

CO Measurement: Evolution with time of the CO fraction in 

the air (see additional notes) 

It should be noted that in the case no additional information was provided in the test, the letters “N/A” 

should be used to indicate that the information was looked for in the reference report and it was not found. 

3.2.	 Filling up the Columns of values describing the evolution with time of the heat release 

rate 

Columns (E) and (F) are filled up by the participant to the Vulcan Initiative, with respectively: 

• the time, after the test start, at which the HRR measurements were made, in seconds, 

• the corresponding Heat Release Rate, in kilowatts. 

The cells have been formatted so that the values inputted in these two columns appear as integers and 

with the comma indicating a 1000 separator. 

The participant has to verify that the values of column (E) are always increasing. 

There are many ways to abstract this information from a graph if the numerical data is not provided. One 

way is to use Engauge Digitizer Software which is an open source program that allows you to trace over 

the image of a graph (available at: http://digitizer.sourceforge.net/). 

Participants must remember that only one HRR curve is permitted per template. In consequence, test 

replicates will have their own Item Number and will be on its own Item sheet. 

3.3.	 Auto-creating the corresponding HRR curve 

The graph of the HRR curve will automatically be created when the participants fills up cells in the 

Columns (E) and (F). The tile of the graph has to be manually changed from “Specimen” to the name of 

the tested item. 

3.4.	 Presenting additional notes and comments 

The “Additional Notes” is located at the upper right part of the template. It can be used for any other 

comment such as another parameter that is not part of the template. Also, it can be used to indicate if 

replicates tests were conducted. It should be clear that replicate tests consist of the exact test repeated. 

Any changes to the test sample, such as conditioning, or the testing method is not considered a replicate. 

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This part can include photos, video links of the test, as well as comments from the participant concerning 

the test. 

4. Instructions on how to fill up the “Overview” sheet 

Once the “Item” sheet has been completed, the participant needs to enter the corresponding information to 

the “Overview” sheet and create a hyperlink to his newly created “Item” sheet. 

A peer reviewer having verified an “Item” sheet should also complete the corresponding cells in the 

“Overview” sheet. 

5. Instructions for a peer-reviewer of the HRR_Catalog 

The HRR_Catalog contains information about the participant who kindly provides data for the Fire 

Protection Engineering community. Another important action is asked for another participant to the 

Vulcan Initiative, who would act as a peer-reviewer of the “Item” submitted by the initial participant. 

In that case, it is asked from the peer reviewer to complete the corresponding cells in the “Item” sheet(s) 

the peer-review was done as well in the “Overview” sheet. 

THANK YOU FOR YOUR PARTICIPATION TO THE VULCAN INITIATIVE
 

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Additional Reference Examples: 

Basic Format for Books 

Author, A. A. (Year of publication). Title of work: Capital letter also for subtitle. Location: Publisher. 

Babrauskas, V; Lawson, J.R.; Twilley, WH (1982) 

Two Authors 

List by their last names and initials. Use the ampersand instead of "and." 

Three to Seven Authors 

List by last names and initials; commas separate author names, while the last author name is preceded again by 

ampersand. 

Article from an Online Periodical 

Online articles follow the same guidelines for printed articles. Include all information the online host makes 

available, including an issue number in parentheses. 

Author, A. A., & Author, B. B. (Date of publication). Title of article.Title of Online Periodical, volume 

number (issue number if available). Retrieved from http://www.someaddress.com/full/url/ 

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Annex G 

The VULCAN INITIATIVE: a web platform for the next generation of 

performance-based fire protection design 
 

 

 

 

 

 

 

 

 

 

 

 

THE VULCAN INITIATIVE: A WEB PLATFORM FOR
 

THE NEXT GENERATION OF PERFORMANCEBASED FIRE PROTECTION DESIGN*
 

Alberto ALVAREZ, Ph.D., Matthew A. FERREIRA & Brian J. MEACHAM, Ph.D., P.E.
 

Worcester Polytechnic Institute, USA
 

ABSTRACT 

For decades, various building regulations around the world have allowed fire safety design of 

buildings to be based on expected performance (e.g., allow occupants adequate time to escape in the 

event of fire) rather than prescriptive requirements (e.g., maximum travel distance to an exit shall not 

exceed 100m). Although this performance-based approach concedes more flexibility and innovation 

for intricate buildings, its application and acceptance has varied widely due to the complexity of the 

process and lack of widely accepted values for key parameters, such as level of performance or risk. 

Current versions presented in various codes, guides and guidelines intrinsically link the technical 

issues with political issues, making it difficult for stakeholders to decide on the acceptability of the 

proposed engineering solutions. This observation has led to a new conceptual design procedure for 

fire protection design that basically separates, as much as possible, the technical aspect from the 

political aspect of the current performance-based fire protection processes. 

It has been further observed in such processes the reliability of the fire protection measures is 

often not taken into consideration, at least explicitly, since there is nothing in the benchmark 

requirements about reliability and is therefore not addressed in performance-based solutions. This 

observation has led to the need to characterize the fire risk of building use groups based on fire 

statistics collected for existing buildings of a same building occupancy class. Fire risk characterization 

of a new project, designed with the performance-based option, should then be compared with this 

baseline to assess its acceptability. 

A third observation is that the current approach to performance-based design often neglects 

the lifecycle of the building and the affect that may have on fire safety performance. This observation 

has led to the need to consider a fire protection engineering study as one component of an overall 

safety study of the building in use, with fire to be viewed as a possible acute event which perturbs the 

otherwise chronic operation of a system (building-occupants-use interaction). 

The final observation relates to the use of tools when assessing the consequences of the fire 

design scenarios. Independently of the validation of tools, user effects are numerous and their 

influence needs to be weighed in the overall performance-based design process, as part of 

uncertainties in the quantification of design fire scenario consequences. This requires better guidance 

on selecting tools for a specific application, data for use in the tools, and a better understanding of the 

complexities of the tool-application-justification decision. 

RESULTS 

As a result of these observations, the first part of this paper presents the framework for a new riskinformed performance-based approach which has been developed. It illustrates how collection of 

better data can assist in risk characterization, scenario development and design fire quantification 

using examples for different building occupancy types. 

A web platform called the Vulcan Initiative for data collection and dissemination, and for 

facilitating broad stakeholder involvement in the development and refinement of work started in this 

effort, will be introduced and discussed in the second part of this paper. 

* Unformatted manuscript for paper: Alvarez, A., Ferreira, M.A. and Meacham, B.J., “The VULCAN INITIATIVE: a web platform for 

the next generation of performance-based fire protection design,” Proceedings, Interflam 2013, Interscience Communication, Ltd., London, 

June 2013. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The corresponding overall research project aims to produce more specific design guidance, 

and potential modifications to building codes, to advance the application, implementation and 

acceptance of risk-informed performance-based fire protection analysis and design options for the 

built environment. It will help engineers better identify, characterize and assess critical fire risk and 

hazard mitigation issues based on differences in building occupancy types, to introduce a new 

framework for identifying and clustering risk-significant fire scenarios, to more appropriately select 

fire analysis and modeling tools to match the specific application, and to take more account of 

lifecycle operation and maintenance aspects of building use. The associated web platform will also 

result in tools and methods for better managing engineering data needed for analysis and design, as 

well as providing a forum to enhance links between the fire engineering community and the broader 

group of interested and affected stakeholders in the building design and operation process. 

FRAMEWORK FOR A NEW RISK-INFORMED PERFORMANCE-BASED APPROACH 

A review1,2 of the last two decades of application of the performance-based fire protection design 

(PBFPD) option concluded that challenges still need to be overcome in order to expand this option as 

an alternative to prescriptive requirements. The main challenge fire protection engineers (FPEs) still 

meet is related to the generic aspect of the current PBFPD processes presented in codes, standards, 

guides and guidelines; thus requiring FPEs to spend significant time and resources when applying 

these generic processes to specific projects. Besides, technical challenges are identified when FPEs 

need to specify process parameters such as performance criteria, select and quantify design fire 

scenarios, and select appropriate tools and corresponding data in order to perform the analysis of trial 

designs. Political challenges related to the decision making framework in which the PBFPD processes 

are used, are also identified and concern the relative roles and objectives of all the different involved 

stakeholders. 

Shortcomings are also identified from the fact that the FPEs are focused on the assessment 

and design of fire protection measures related to a list of design fire scenarios the involved 

stakeholders agreed upon. In other terms, the sets of fire protection measures established after 

applying current PBFPD processes correspond more to "idealized" independent design features than 

"real life" installed, running features, integrated as a component of a global system formed upon 

building components and occupant characteristics. This situation led to cases where fire protection 

measures were ignored, or even rejected by the system in which they were installed due to 

incompatibilities between the real usage of the system and the conceptual design of the fire protection 

measures, as occupants are focused on their activities and do not think about how these activities may 

compromise the efficiency of fire protection measures. Examples of such cases are given 

elsewhere1,2,3 and are observed during inspections (fire doors maintained opened and blocked 

emergency exits). 

Besides, stakeholders are focused on the performance of their building on a daily basis. 

Design fire scenarios defined in current PBFPD processes only consider fires between ignition and 

extinguishment. Nevertheless, recovery period should also be considered between fire extinguishment 

and the time when the building is back in full operative mode, as this recovery period could be 

significant for the stakeholders in terms of business continuity objective4

. In consequence, FPEs need 

to consider fires as disruptive events of a "building occupant" system formed by a building and its 

occupants, between two "chronic" states of this system, not only taking into consideration the fire 

itself between ignition and extinguishment, but also the recovery period leading to a "chronic" state or 

state corresponding to a normal daily basis system operation5

. 

Addressing these shortcomings requires that FPEs shift their current study paradigm focused 

on the design of fire protection measures based on the analysis of design fire scenarios to a paradigm 

for which building performance metrics are evaluated in the case of fire events so that sets of fire 

protection measures could be fully integrated and compatible with the building usages. The 

characteristics of a "building occupant" system are detailed elsewhere2,5. 

Along with this "building-occupant" system paradigm, a risk performance-based process has 

been established and focused on assessing the overall performance of the system in case of any type 

of event affecting its performance2,5. Then, this process has been detailed for the treatment of fire 
 

 

 

 

 

 

 

 

events and compared with current PBFPD processes. Figure 1 presents the new PBFPD process, 

showing, by comparison with a current PBFPD process, that: 

•	 a new technical step dedicated on the evaluation of the integration into the system of the fire 

protection measures, selected after the fire risk analysis, 

•	 a technical step dedicated to a required cost-benefit analysis. 

•	 a complete separation between the "political" decision-making process and the "technical" 

resolution of the engineering fire problem, operated once in a straightforward manner. 

Indeed, at the start of the process, project stakeholders define the characteristics of their 

system and establish the "targets" (defined as actors of the global system performance) and 

the current "chronic" state of the system. At the end of this technical part of the new process, 

FPEs have elaborated three documents detailing the results of the target-oriented fire risk 

analysis, of the evaluation of the integration of the fire protection measures into the system 

and of the cost-benefit analysis. Based upon these documents, the stakeholders decide which 

fire protection measures they would have installed in their system. 

Although the proof of concept2,5 was established for the new PBFPD process, specific guidelines 

related to the application of each process step to different types of systems (e.g., schools, hospitals) 

are yet to be established. Each specific guidance is planned to describe the different actions for the 

FPE to perform, a list of most appropriate tools to use (and the way to use them so to reduce the user 

effects and its corresponding uncertainties), and the system specificities to look at. This guidance will 

be associated with databases for input data needed to use the tools for the different technical steps of 

the new PBFPD process. 

Technical steps of the overall system performance-based process 

Target 

vulnerability 

criteria 

estimation 

Fire risk 

analysis 

(quantification 

of the impact) 

Cost-benefit 

analysis 

Fire risk 

characterization 

Fire risk 

analysis 

(quantification 

of the 

likelihood) 

Evaluation of 

the integration 

of the fire 

protection 

measures in 

the system 

Political 

Stakeholders’ 

project 

definition 

Political 

Stakeholders’ 

decision 

Figure 1. New Performance-Based Fire Protection Engineering Design (PBFPD) process 

THE VULCAN INITIATIVE 

Origin and objectives of the Vulcan Initiative 

Actions FPEs would be required to perform for each of the six technical steps of the new riskinformed PBFPD process, are detailed elsewhere2

. It should be noticed that these actions can be 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

similar to or different from the ones performed in the current PBFPD processes. For each step of the 

process, a plan of action has been proposed in order to describe the nature of the information that 

would be inscribed in the future guidance, and how this information would become a part of future 

guidelines and standards. First useful elements of information extracted from past and current 

research involving experts from a large spectrum of competencies and systems stakeholders, as well 

as information from standardization efforts were also gathered for each step2

. 

This plan of action is assumed to be impossible to be supported by a single entity of the Fire 

Protection Engineering community. Not only the research would be too costly in terms of time and 

resources but it also has to involve stakeholders (as they are the ones who can define the targets of 

their system and know how their system operates on a daily basis), engineers from other fields than 

fire protection engineering (e.g., psychologists, structural engineers, economists), as well as policymakers and authorities having jurisdiction. Thus, there is a need of an environment which is flexible 

enough to allow all these kind of people to communicate and exchange information, for extended 

periods of time. Besides, research related to the different technical steps of the new PBFPD process 

develops at a different pace and may vary of interest for different people within the Fire Protection 

Engineering community (practitioners, researchers, tool developers, academia) and people dealing 

with building projects (design team, fire services, authorities having jurisdiction). Thus, there is a 

need of an environment which is flexible and adaptable enough to allow the dissemination of results 

from research conducted on the technical steps of the new PBFPD process. 

It appears that a web platform environment would be the best way to implement the two 

points above, in conjunction with the ultimate objective to facilitate and speed up the establishment of 

the guidelines related to each step of the new PBFPD process. This web-platform environment is 

named the Vulcan Initiative. It is accessible through the web address: http://vulcan-initiative.net. It is 

organized mainly through 'test bed' environments, the implementation of tool input databases and 

projects related to the use of the new PBFPD process. 

'Test bed' environments 

Origin and characteristics of 'test bed' environments 

While solving real-life problems, engineers are used to quantifying parameters that are relevant for the 

analysis they are undertaking. In order to do so, they use tools for which they apply input data that is 

representative of the examined problem. Because real-life solutions require the approval of authorities 

having jurisdiction, tools are required to be validated for the considered problems. Besides, 

concerning fire protection engineering problems, the analyzed phenomena are complex and still 

nowadays necessitate a lot more research not only in the evaluation of fire effects itself but also in the 

evaluations of building evacuation and structural response. Having models and research tools used 

appropriately when analyzing trial designs in a performance-based design framework is even more 

difficult due to the complexity of building geometries influencing fire effluent spread, the diversity of 

human behaviour patterns, and the intricacies of diverse structural elements. To these research 

difficulties, are added engineering difficulties due to the fact that FPEs still need to mix all the results 

provided by these different research tools to perform their analysis and that these complex tools 

require FPEs to be able to use them (user effect6

). 

It should be noted that even if technical guidance has recently been published for fire effects 

tools7

, this guidance is still too generic and therefore implies FPEs to figure out how it could be 

applied to a specific project. Besides, there is still a need for the same kind of guides for evacuation 

tools and structural response tools, as well as the additional layer when mixing all the results for these 

tools. In order to attenuate these difficulties and overcome these challenges and needs, it was decided 

to concentrate our efforts on well-defined engineering problems called 'test bed' environments. 

If one positions all the possible building configurations in the y-axis and all the possible 

building occupant distributions in the z-axis, one can see distinctive domains appear on such a 

representation. If keeping the building configurations in the y-axis and adding a z-axis for the fires 

that are susceptible to occur in these different building configurations, one can also see distinctive 

domains appear as different buildings configurations differ in terms of geometry, size and structure, 

and from the nature of the combustibles located in these configurations; all influencing the fires 
 

 

 

 

 

 

 

 

susceptible to occur in these configurations. At last, by looking at populations (z-axis) and fires 

affecting these populations (x-axis), one can see domains where fire effects (and the means of 

evacuation) are based according to occupant characteristics, and more particularly according to 

defined classes of vulnerable populations (see Figure 2). Within this three dimensional representation 

involving all the possible buildings, occupants and fires, discrete domains appear which clusters the 

characteristics of well defined environments that we define as domains of interest or 'test bed' 

environments. 

Occupants 

Fires 

Entire domain 

Domains of interest for the 

Tool Users 

Domains of tool validation for 

the Tool Developers 

Figure 2. Schematic representation of all the different possible domains linking buildings, occupants 

Quantifying domains of interest for 'test bed' environments 

As explained in the previous paragraph and illustrated in Figure 2, domains of interest potentially 

defining 'test bed' environments can be delimited by different types of buildings, or "building 

occupant" systems if following the system paradigm defined in the first part of this conference paper. 

Data characterizing these domains have to be gathered so that: 

•	 FPEs (tool users) can quantify the input data for the tools they would use to conduct their 

engineering analysis, whatever the tools are used for assessing consequences of fire effects, 

fire scenario probabilities, cost-benefits of sets of fire protection measures or integration of 

these measures into an examined system (Step 5 of the new PBFPD process). 

•	 Tool developers are aware of the needs for validation of their tools around these domains and 

concentrate their efforts for these domains in terms of tool validation and model development. 

In that matter, it should be noted that the EXODUS suite of software tools designed to 

simulate the evacuation of large numbers of people from a variety of enclosures, contains 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

buildingExodus, maritimeExodus, airExodus and railExodus (under development) are an 

example on how tools, based on the same generic principles, have to be specialized according 

the specificities of the enclosure. 

Considering building evacuation process, occupants characteristics can be defined according 

to the building use, so data characteristics for different sets of (building-occupants) domains should be 

determined so to anchor the needs for the engineer to solve problems related to these sets and help the 

evacuation tool developer to increase the analytical power of their tools for these sets. 

For example, in the USA, statistics and data on population distributions can be found at the 

Center for Disease Control (http://www.cdc.org) website for population distribution in short stay 

patient in hospitals. For the period 1968 - 2010 (see Figure 3), the distribution of short stay patients in 

hospitals saw the decrease of the percentage for children and young adults (up to 34 years old), the 

increase of the percentage for older adults and the large increase of the percentage for elderly 

population (75 years old and older). Without this type of data and other associated data (e.g., 

distribution of these patients in the different areas of the hospital, how many people are connected to 

life-supporting machines?), FPEs cannot really estimate the evacuation process of hospital patients 

(how long will it take to prepare a patient for evacuation? How fast is the "walking speed" of a group 

composed of the evacuated patient and his/her nurse(s)?) and what incidence would this population 

distribution have on the evacuation management plan of hospitals? For evacuation tool developers, 

how do they model such a group where the patient is on a wheelchair or carried in a litter? For 

business continuity objectives, other useful information regarding lengths, reasons and costs of 

hospital stays can also be found on the Internet8

. 

Data concerning buildings can be found, for example, at the US Energy Information 

Administration9

. This data can be used to describe the building stock according to their occupancy 

types and functions10 (e.g., offices and all different kinds of hospitals - general hospitals, psychiatric 

hospitals). This kind of data was already used within a risk-informed perspective, to quantify fire risk 

for different types of buildings11. More data of this type needs to be gathered and analyzed. In a 

similar manner, building characteristics including geometry and types of combustibles that can 

influence fire ignition and spread should be studied so that (fires-buildings) data sets could be 

established for different building types. Fire loads have been established by building occupancy 

types12 but there is still a need to standardize the way of collecting the data, as well as a more detailed 

description of the combustible contents in the different areas of a considered building13. 

Figure 3. Evolution of the population distribution in short stay patients in hospitals between 

1968 and 2010 (source: compiled from data US Centers For Disease Control and Prevention / 

National Center for Health Statistics) 

At last, effects of fires on occupants should also be determined for different domains, since 

untenable conditions may vary according to occupants characteristics and FPEs analysis would need 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

to emphasize on the vulnerable occupants. It should be noted that one component of the data can be 

gathered by FPEs as presented above for population distributions in hospitals while the other 

component of the data still require the contributions of toxicologists and psychologists to model the 

effects of fires on building occupants, so that ultimately tool developers could implement their 

respective fire effects and evacuation tools with the corresponding models. 

In conclusion, in the previously defined "building occupant" system paradigm, tools and 

databases for tool input data are necessary to perform every technical step of the new PBFPD process, 

as they are usually needed in order to solve any engineering problem. Nevertheless, it is unpractical to 

look for validated tools and associated databases that could be applied to all possible domains where 

the tools could be used. Thus, 'test bed' environments are set up around specific domains defined by 

specific "building occupant" systems. These domains need to be quantified so that FPEs are able to 

evaluate how these values would impact their engineering analysis and so that tool developers 

concentrate their model validation and development efforts on these domains. 

'Test bed' environment studies: solving fire protection engineering issues 

Now that the procedure related to the definition and the quantification of 'test bed' environments is 

established, all this information still need to be processed so they can be used for the establishment of 

guidelines related to each technical step of the new PBFPD process. In order to do so, real "problem 

solving" engineering studies have to be associated with 'test bed' environments. Indeed, it is required 

to have usable tools and corresponding input data, but still it is necessary to guide FPEs in the 

selection of appropriate tools and data to be used to solve well defined issues and how to conduct the 

analysis to solve the issues. 'Test bed' environments studies were primarily focused on the use of tools 

for assessing fire consequences14, as this assessment is one key element of the PBD approach: 

•	 Dynamic way to evaluate fire effects vs. evacuation process for a hospital horizontal 

evacuation. As previously indicated, no guidance is given concerning the global 

quantification of the evacuation process. For a L-shape or T-shape hospital, a zone model 

may be appropriate to assess fire effects along with simple hydraulic calculations to assess the 

evacuation process. For other more complex hospital layouts, a CFD model may be more 

appropriate. If not providing the FPE with the same exact answer, would the use of the two 

fire effects tools make the FPE conclude with the same engineering solution? How are 

assessed the interacting key events of fire spread (e.g., exit pathways being untenable, 

activations of fire detection and suppression) and of evacuation (e.g., pre-movement time, 

successive patient preparation for evacuation, nurse travel back and from the horizontal safe 

place)? 

•	 Description level of details needed for a near field analysis and a far field analysis. 3-D fire 

simulations are costly in time and computing resources. For some engineering problems, it 

may be necessary to know precisely how the fire is spreading in the near field of fire start 

(i.e., to describe ignition of subsequent burning items), while in the far field, the concern is 

fire effluent transport and temperature elevation. Different computational meshes along with 

different levels of detailed geometry may be used to solve this type of problems at once but 

there is no guidance for the FPEs to know how to do that. 

The answer to these questions (and many more) can come from parametric studies performed by 

students in Academia, engineers all around the world, as multiple independent ways to look at these 

problems, as well as different "ways of doing". The web-platform is a good way to coordinate all the 

study results, flexible without constraints of usual meetings and document management. Phases to 

establish and conduct a 'test bed' environment related to the quantification of fire consequences are 

described elsewhere, as well as the different roles of all the actors involved in the corresponding 

issues14,15. 

Tool input databases 

The need to get databases that are relevant and easily accessible 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The Internet already makes accessible numerous reports related to fire experiments and other 

resources that are relevant for fire engineering purposes. Nevertheless, in many countries, lots of 

reports still remain unused because they are not searchable in English. Agencies such as INERIS in 

France, SP in Sweden, and VTT in Finland, which publish a large quantity of reports in their 

respective websites but mainly in their native language, are not known as they should be. Through its 

forum, the Vulcan Initiative will try to encourage the dissemination of knowledge from non-English 

speaking countries. Attempts to make data available have been made concerning the heat release rate 

parameter but unfortunately they remain not fruitful because of a lack of maintenance (resources were 

allocated for a short period of time) and flexibility (it is almost impossible for someone else than the 

website owner to upload new data). The Vulcan Initiative will provide links to existing databases and 

will include its own database related to combustion experiments. 

Many databases are needed not only for HRR 

Data is required for different types of analysis FPEs may have to perform, including fire risk analysis 

in a PBD framework (looking for data on probabilities and consequences of design fire scenarios), 

code change analysis, product evaluation analysis, or major fire reconstruction16. Data types and 

sources, organized around incident data, field observation, usage or exposure data, and laboratory test 

results have been discussed in terms of availability, representativeness, applicability limitations and 

discrepancies between databases of the same type16. Even if important precautions are already 

associated with the use of such databases, we observe there is still a lot to do in terms of helping FPEs 

with being aware such databases exit, knowing what the data really represent, and using the data 

appropriately for their engineering analysis. 

Besides, even if data such as heat release rates could "speak" a lot to FPEs because of their 

academic background, it is less sure than statistical data on fire ignition probabilities are correctly 

perceived by FPEs. As FPEs get more and more involved in risk-informed PBD analysis, they will 

look for more and more information related to the characterization of fire risk. For example, 

concerning fire risk curves linking the probability of a fire with damage areas, the lumped results 

presented in the late 1970's from UK have seen some diversified attempts in Japan, Finland, Sweden 

and more recently in Slovenia17, with the inclusion of parameters such as daily work operation period 

and number of employees. We conclude that FPEs should get more involved in the definition of the 

data that could be treated via statistical methods (or statisticians) as they are the end users of all this 

data. Some parameters such as the one considered in the Slovenian study may or may not be relevant 

for other types of "building occupant" system than the studied one. Without that action, the data that is 

really needed would never be collected and the FPEs would have to use "engineering judgment" to fill 

the gap between currently available data and really needed data. 

Projects related to the new risk-informed PBFPD process 

As the Vulcan Initiative was created as a way to facilitate the establishment of guidelines for each 

technical step of the new PBFPD process, it already contains the structure with which one can upload 

a "project". A project contains the characteristics2,5 of a "building occupant" systems, such as the 

building layout, the list of stakeholder targets. 

In the Vulcan Initiative, one participant willing to apply the new PBFPD process for a 

particular project will successively go through the following components: fire risk characterization 

will include databases on fire statistics and on the census of specific systems, fire damage criteria will 

include databases on how fire can affect people and building contents that are relevant to stakeholders 

for property protection or business continuity objectives. Fire risk analysis will include tools to assess 

the likelihood and the consequences of fires, as well as their corresponding databases relative to fire 

ignition frequencies, reliability of fire protection measures, production of heat and fire effluents from 

combustible packages, human behavior and structural response. Cost-benefit analysis will include 

tools to assess the cost of installing and maintaining fire protection measures in specific systems. 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

Participants to the Vulcan Initiative are welcome to upload the projects of their choice, at the 

present time even if there is still a lot of research to be undertaken to complete the guidelines. By 

doing so, they will provide needed input data which could be used for 'test bed' environment studies 

described above. By sharing the characteristics of their system and presenting the issues related to 

their project, these "project owners" could be joined, in the short term, by others in the Fire Protection 

Engineering community having the same issues. On the long term, they will ultimately benefit from 

the results of the studies as these results will be applied to their own project or similar projects (see 

Figure 4). 

Examples of projects to be uploaded to the Vulcan Initiative site include a hospital, a highrise hotel and a mall, created in Academia, from the Worcester Polytechnic Institute (WPI), USA. The 

5-story hospital was based on an actual building design, modified with specific features such as a 

‘function space,’ so as to allow students experience in assessing different fire scenarios and 

evacuation, protect in place and relocation scenarios. The 30-story high-rise hotel with associated 

convention space was developed at WPI to provide an environment within which to have students 

assess such factors as fire scenarios, evacuation schemes and mitigation measures (such as smoke 

exhaust in atria and meeting spaces). The 3-story shopping mall was likewise developed at WPI to 

have students assess such factors as fire scenarios, evacuation schemes and mitigation measures (such 

as smoke exhaust and material control). These projects can serve as examples for future students, and 

new projects could be added to the Vulcan Initiative using these configurations and associated data. 

WPI hopes to be joined by other institutions around the world, as well as tool developers, architects, 

code officials and others, from whom advice could be requested and interaction in the virtual 

environment can help address 'real world' issues and facilitate development of new detailed guidelines 

as outlined above. 

Figure 4. Organization of a "project" in the Vulcan Initiative 

Tasks related to a "project" 

Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 

"Project owner" 

uploads input data 

(system 

characteristics) 

"Project" participants 

get the results of the 

PBFPD process 

"Project" participants can help for one or several of the PBFPD process steps 

CONCLUSION 

To address shortcomings with the current performance-based approach, a research project is 

developing detailed guidance for the fire protection engineer to assist in the development of riskinformed fire safety options that could be implemented and maintained during a building life span. 

In order to support the establishment of this detailed guidance, a web platform, called the 

Vulcan Initiative, has been created around the technical steps of the new conceptual procedure for fire 

protection design. Each of these steps is related to the quantification of engineering parameters, which 

requires the use of appropriate tools and associated input databases. Since our aim is not sciencefocused but engineering-focused, specific domains that are relevant to building projects called 'test 

bed' environments are created for each fire issue to be solved for a specific system (buildingoccupants-use interaction) so to speed up the current and future validation domains of engineering 

tools around these environments, instead of waiting to have these tools validated for all the possible 

physical domain. 

One ultimate goal of the Vulcan Initiative where information and knowledge are exchanged 

among tool users and stakeholders is to create new guidelines on the appropriateness of tools for a 

given application, all along the new risk-informed performance-based process steps. In order to do so, 

participants are welcome to upload "projects" containing the characteristics of "building-occupant" 

systems of their choice. Projects involving a hospital, a high-rise hotel and a mall, created by WPI as 

part of courses in the Fire Protection Engineering program, will be posted to the Vulcan Initiative site 
 

 

 

 

 

 

 

 

 

as a model for others and to stimulate specific analyses, discussions and development of data and 

information needed for the ongoing development of PBFPD and required guidance. 

Even if they are not interested in applying the new PBFPD process, participants in the Vulcan 

Initiative can find benefits in contributing to any 'test bed' environment studies as some of these 

studies reflect concerns of the current PBFPD processes (e.g., concerns related to the quantification of 

fire scenario consequences), as well as using and providing data useful to perform any of these 

studies. 

Participants from all the spectrum of the Fire Protection Engineering community (Academia, 

research agencies, industry, authorities) are welcome as they can all contribute and benefit from the 

Vulcan Initiative. 

ACKNOWLEDGEMENTS 

The authors would like to gratefully acknowledge the financial support provided by the National 

Institute of Standards and Technology (NIST) under award 60NANB10D228 which facilitated the 

research and outcomes as described herein. This award was used to support a large number of 

graduate students in the Department of Fire Protection Engineering who contributed to this effort. 

REFERENCES 

1 Alvarez, A., Meacham, B.J., Dembsey, N.A. and Thomas, J.R., 20 Years of Performance-Based 

Fire Protection Design: Challenges Faced and a Look Ahead, Journal of Fire Protection 

Engineers, submitted Aug. 12th, 2012, submission number: JFE-12-0035 

2 Alvarez, A., An integrated framework for the next generation of risk-informed performance-based 

design approach used in fire safety engineering, Ph.D. thesis, Fire Protection Engineering 

Department, Worcester Polytechnic Institute, December 2012 

3 Alvarez, A., Meacham, B.J., Dembsey, N.A. and Thomas, J.R., A framework for risk-informed 

performance-based fire protection design for the built environment, Journal of Fire Protection 

Engineers, submitted April 8th, 2013, submission number: JFE-13-0016 

4 Sheffi Y., The Resilient Enterprise, Massachusetts Institute of Technology Press. 2005 

5 Alvarez, A., Meacham, B.J., Dembsey, N.A. and Thomas, J.R., Using a Systems Approach to 

Holistically Assess Building Performance during disruptive events, to be submitted in May 2013 

to Building Research and Information 

6 SFPE, The SFPE Code Official's Guide to Performance-Based Design Review, 2004 

7 SFPE, SFPE guidelines for substantiating a fire model for a given application, SFPE G.06 2011, 

Society of Fire Protection Engineers, 2011 

8 HCUP Facts and Figures: Statistics on Hospital-Based Care in the United States, 2007, available at 

(http://www.ncbi.nlm.nih.gov/books/NBK53001/), last checked April 23rd, 2013 

9 US Energy Information Administration (EIA) - 2003 Commercial Buildings Energy Consumption 

Survey (CBECS) Detailed Tables – most recent available, released: September 2008 

(http://www.eia.doe.gov/emeu/cbecs/cbecs2003/detailed_tables_2003/detailed_tables_2003.html# 

enduse03) 

10 Alvarez, A. and Meacham, B.J., Towards an Integrated Performance-Based Design Approach for 

Life Safety Across Different Building Use Groups, in: Proceedings of the 12th International 

Interflam Conference, Nottingham, UK, 5-7 July 2010, Interscience Communications Ltd, 

London, UK, p1259-1270, 2010 

11 Kobayashi, Y. and Nozaki, H., A Statistical Method to Evaluate Fire Risks in Non-Residential 

Buildings in Japan," in: Fire Safety Science: Proceedings of the Eight International Symposium, 

China, International Association for Fire Safety Science, pp. 341-352, 2005 
 

12 Bukowski, R.W., Determining Design Fires for Design-level and Extreme Events, in: Proceedings 

of SFPE 6th International Conference on Performance-Based Codes and Fire Safety Design 

Methods, June 14-16, 2006, Tokyo, Society of Fire Protection Engineers, 2006 

13 Department of Veterans Affairs, Structural Design Manual for Hospital Projects, 2009 

14 Alvarez, A. and Meacham, B.J., Ready-to-use" Building Layouts and Combustible Packages for 3­

D simulations. In: proceedings of the Fire and Evacuation Modeling Technical Conference, 2011 

15 Alvarez, A. and Meacham, B.J., 'Test bed' environment process for assessing the appropriateness of 

engineering tools to be used in performance-based design applications, in: Proceedings of the 9th 

International Conference on Performance-Based Codes and Fire Safety Design Methods, Hong 

Kong. 20-22 June 2012 

16 Ahrens, M. and Hall, J.R., Data for Engineering Analysis, Chapter 5, Section 5 of the 4th edition of 

the SFPE Handbook of Fire Protection Engineering, SFPE, 2008 

17 Šrekl, J. and Golob, J., Impact of The Buildings Areas on the Fire Incidence, Acta Chim. Slov., 57, 

118-122, 2010 
 

Annex H 

The VULCAN INITIATIVE: Beta Version Web Pages 
 

 

Vulcan Initiative Homepage 

About V.I. 

Objectives 

Disclaimer 

Organizati 

on 

Fire Risk 

Characteriza 

tion 

fire risk 

characterzation 

Tools 

Fire Risk 

Characterization 

Databases 

Fire 

database 

Fire 

events 

Fire 

statistics 

Building-occupant 

system database 

Test bed 

environments 

Target 

Damage 

Criteria 

Fire Risk 

Analysis 

(likelihood 

) 

Risk 

Analysis 

Tools 

Event 

trees 

Fault 

Trees 

Risk 

Analysis 

Databases 

Fire Ignition 

Frequencies 

Fire Protection measure 

Reliability Databases 

Test bed 

environments 

Fire Risk Analysis 

(impact) 

Fire 

Impact 

Tools 

Fire 

effects 

Evacuatio 

n 

Structure 

response 

Databases for 

Engineering 

calculations 

Fire 

effects 

Fuel 

packages 

experimental 

database 

links 

(including 

report links) 

Human 

behavior 

Structural 

response 

Test bed 

environments 

List of on-going 

'test bed' studies 

Project 1 

Pre-processing phase 

Processing phase 

Post processing phase 

Project 2 

Set New 

Project 

Available building 

configurations 

Integration of 

FP measures 

System 

dynamics 

Tools 

Contengency 

plan 

Databases 

Test bed 

environments 

Cost-Benefit 

Analysis 

Economics 

Tools 

Monetary Loss 

Databases 

Test bed 

environments 

Info 

Open 

Forum 

Questions 

about the 

webste 

Open 

questions 

Calendar 

of Events 

Members 

info 
This is the website banner, 

at the top of every page 

Homepage of Vulcan initiative 

Banner 

Performance-Based Fire Protection Design Process Technical Steps 

HOME Risk 

characterization 

Damage 

criteria 

estimation 

Fire risk 

analysis 

(quantification 

of the 

likelihood) 

Fire risk 

analysis 

(quantification 

of the impact) 

Evaluation of 

the integration 

of the fire 

protection 

measures in 

the system 

Cost-benefit 

analysis INFO 

Tools 

Databases 

'Test Bed' 

environments 

When the mouse is over "fire risk 

analysis (qn of the impact)", the 

sub-menu appears 

Tools 

Databases 

'Test Bed' 

environments 

Fire effects 

tools 

Evacuation 

tools 

Structural 

response tools 

When the mouse is over "Tools", 

the "sub-sub" menu appears 
 

Tools 

Databases 

'Test Bed' 

environments 

When the mouse is over 

"Databases", the "sub-sub" menu 

appears 

Fire effects databases 

Human behavior 

databases 

Structural response 

databases 

Tools 

Databases 

'Test Bed' 

environments 

When the mouse is over "'Test 

Bed' environments", the "subsub" menu appears 

On-going projects 

Create a new project 

Select /upload a 

building configuration 
Open Forum 

How to 

participate? 

List of 

Participants 

When the mouse is over "INFO", 

the sub-menu appears 

Damage 

criteria 

estimation 

Fire risk 

analysis 

(quantification 

of the impact) 

Cost-benefit 

analysis 

Fire risk 

characterization 

Fire risk 

analysis 

(quantification 

of the 

likelihood) 

Evaluation of 

the integration 

of the fire 

protection 

measures in 

the system 

Performance-Based Fire Protection Design Process Technical Steps 

INITIATIVE 

INFO 

INITIATIVE 

HOME 
 

 

 

 

 

 

 

"Vulcan Initiative" Homepage 

The Vulcan Initiative is a website dedicated to help the Fire Protection Engineering community with the 

application of Performance-Based Fire Protection Design (PBFPD) option. 

This website was set up around a new risk-informed PBFPD process, which aim is to assess how fire 

events affect the overall performance of a system formed by specific building types and their associated 

occupants (called "building-occupant" systems). This new process contains technical steps that are 

separated from the ones where project oriented decisions are taken by the considered stakeholders. This 

separation allows Fire Protection Engineers (FPEs) after gathering the characteristics of the system to 

study, to independently treat fire events in a straightforward manner and propose their fire protection 

feature sets to the stakeholders for their final approval. The approval is based on documents showing the 

results of a fire risk analysis, the evaluation of the fire protection features in the system and a cost-benefit 

analysis of these features. 

Guidelines associated with each technical step of the new PBFPD process have to be developed for 

specific "building-occupant" systems. Generic guidance was necessary to present the PBFPD approach 

when it was originally proposed to the FPEs and the code policy makers. Nevertheless, this generic 

attribute turned to be a challenge for the application of the PBFPD option, and it led to the need for more 

specific guidance. 

The Vulcan Initiative has been created in order to be the repository of all the information gathered, from 

the needed research to the establishment of the guidelines elaborated for specific "building-occupant" 

systems. 

The Vulcan Initiative is aimed to facilitate the exchange of information between the different actions of 

the PBFPD process: Fire Protection Engineers (FPEs), stakeholders, decision policy makers, and 

researchers. Participation of Academia is also welcome as teachers can use the information provided 

here as a technical resource and course projects and the students can upload their reports in an active 

effort to improve database contents or the use of models. 

The Vulcan Initiative is organized according to the PBFPD process. Except the step related to the 

evaluation of the integration of the fire protection measures in the system, each step of the process 

requires the quantification of information. This information is estimated using dedicated tools which 

output is the requited information. Input data is necessary for the use of tools and therefore this requires 

the establishment of relevant databases. Validation of tools is a concern across the FPE community. The 

extension of validation domains is often associated with costly experiments. It would be time consuming 

to increase the current validation domains up to their application domains. Since the PBFPD process is 

an engineering one, the validation domains need to encompass the engineering domain limited by the 

specific systems characteristics and their associated issues, i.e. engineering problems related to fire 

events affecting these systems. Within the Vulcan Initiative, 'test bed' environments are then created in 

order to ultimately create guidelines related to the appropriateness of tools and their associated 

databases to be used to solve specific issues concerning specific "building-occupant" systems. 

Clicking on each of the technical step in the banner will send you to a page describing the corresponding 

step. 

Clicking on "Info" will open a sub-menu composed of a "forum" where you can post and review threads 

associated with the Vulcan Initiative, of a "how to participate" and of the lists of participants and their 

current actions. 

Alberto Alvarez - W3

PI (2012-09-28) 
 

 

 

 

"Fire risk Characterization" Homepage 

Stakeholders’ project 

definition 

Political step 

Fire risk characterization Other technical steps of the 

PBFPD process... 

Technical steps 

The stakeholders of a specific "building-occupant" system are mainly interested in the daily performance 

of their system. In the building-occupant system paradigm associated with the new PBFPD process, 

"targets" are defined as the actors of this performance. For example, targets can be building occupants 

(patients including their visiting families and friends and staff in hospitals, pupils and teachers in schools) 

or building contents (important piece of equipment required to contribute to the performance of the 

system such as a newly developed micro-chip in high tech industry or a priceless artifact in a museum). 

The fire risk characterization step is about translating the fire safety engineering problem from a 

stakeholders' perspective to a FPE perspective. 

During the project definition step at the start of the PBFPD process, the project stakeholders have to 

agree on the main goals and objectives related to the considered "building-occupant" system and 

precisely what specific building attributes are of concern (e.g., atrium, high rise configuration). These are 

considered political aspects of the problem, as decisions are required by others than the FPE alone. 

Once decided, all of this information is transmitted to the FPE who starts the technical aspect of the 

PBFPD process by selecting fire risk acceptance metrics that correspond to the considered project. 

Tools that FPEs can potentially use to assess the information relative to the fire risk characterization step 

are fire risk matrixes or fire risk curves, as illustrated. Target damage metric 

Fire frequency 
 

 

Tool Input databases are then related to the assessment of two different types of information: 

- fire statistics which would help to quantify the frequency of fire events with their associated impact of the 

system targets, 

- system statistics which would help to quantify the number of systems upon which fire statistics are 

applied. 

In consequence, 'test bed' environments will be set up for specific "building-occupant" systems 

according to their characteristics. Issues related to a particular 'test bed' environments will be treated in 

relation to the different natures of targets a specific system contains. 

Alberto Alvarez - W3

PI (2012-09-28) 
 

 

 

 

 

"Damage criteria estimation" Homepage 

In the "fire risk characterization" step of the new PBFPD process, fire protection engineers (FPEs) 

collected the system targets (i.e. elements of the system which contribute to its overall performance). 

Then, in the "damage criteria estimation" step, for each considered targets, FPEs have to quantify how 

these targets are affected by direct and indirect effects of fire events, events involving a fire and defined 

between two "chronic" states of the system. 

After reviewing the two decades of worldwide experience using standards, codes and guidelines related 

to PBPFD for buildings [1], we concluded that the performance criteria gathered in the current codes, 

standards and guides and guidelines: 

- should be called "damage criteria" as they quantify more a threshold value at which building occupants 

(and contents) are damaged than the performance of the considered project to withstand fires, 

- only include the direct effects of a fire (people and building contents are affected by high temperatures, 

high toxic fire effluents and low visibility preventing occupant evacuation or rescue). 

As the new engineering process is target oriented, it is essential to get the metrics allowing the estimation 

of the potential damage to the targets. Damage criteria metrics would have to include: 

- typical criteria related to fire effects to humans (due to thermal threat, toxic threat and loss of visibility 

which impedes evacuation), 

- damage criteria related to stampede, 

- damage criteria related to indirect fire threat to people, 

- damage criteria related to safety equipment, building contents (e.g. for heritage preservation) and 

- damage criteria related to the use of fire protection measures (sprinkler, fire fighting) on building 

contents and systems. 

These damage criteria have to be collected and the process by which the damage is assessed has to be 

a result of an agreement within the scientific community not only involving fire protection engineers but 

also: 

- toxicologists, psychologists, etc. when the targets are related to the life safety objective, 

- operators, electronics engineers, etc. when the targets are related to the business continuity objective, 

- Structural engineers, etc. when the targets are related to the property protection objective. 

[1] A. Alvarez, B.J. Meacham, N.A. Dembsey, J.R. Thomas, 20 Years of Performance-Based Fire 

Protection Design: Challenges Faced and a Look Ahead, Journal of Fire Protection Engineers, submitted 

Aug, 12th 2012, submission number: JFE-12-0035 

Alberto Alvarez - W3

PI (2012-10-02) 
 

 

 

 

 

 

"Fire risk analysis (quantification of the likelihood)" Homepage 

For each system targets considered in the "fire risk characterization" step of the new PBFPD process, fire 

protection engineers (FPEs) have to quantify how these targets are affected by direct and indirect effects 

of fire events. Fire events differ from the current notion of fire scenarios: a fire event does not only 

consider the time frame between the iginition and the extinguishment of a fire but it also involves the 

recovery period follwing a fire until the considered system has reach a new "chronic" state, where it can 

perform again in a daily basis. 

Fire risk analysis has then to be conducted in order to characterize the likelihood and the consequences 

of fire events on the targets. The FPE work is then to propose fire protection measures in order to 

minimize the occurrence of the damaging fires and mitigate the impact of these fire events on the system 

performance (i.e. the consequences of the fires events affecting system targets). 

In a deterministic approach, the current PBFPD processes do not specify detailed procedures on how to 

select fire design scenarios or they provide a list from where the FPE and the stakeholders can “pick up” 

and finally agree on the ones to use. Thus, the resulting fire design scenarios fell to consider the chronic 

use of a building, are focused on the fire event instead of being target oriented and miss the importance 

of the recovery phase. 

In this step of the proposed PBFPD process, event trees are elaborated in order to describe quantitatively 

the different fire events. Fault trees are also established in order to characterize all the different scenarios 

leading to target damage, so to capture the indirect threats to the targets. Fire risk models are used in this 

process step to help calculate the scenario likelihoods. 

Tools related to the quantification of the likelihood of fire events may include fault trees, event trees, 

what-if analysis, bayesian networks and "ready-to-use" tools such as FiRECAMTM [1], CRISP [2] and 

FIERAsystem [3]. 

Event tree - Fault tree - Markov chain 

Databases related to the quantification of the likelihood of fire events may include fire statistics with 

an emphasis on fire ignition frequencies and data on fire protection measure reliability. 

'Test bed' environments will be set up for assessing the appropriateness of tools to quantify the 

likelihood of fire events for specific "building-occupant" systems, along with the corresponding data 

needed to use the tools. 

[1] http://www.firemodelsurvey.com/pdf/FiRECAM_2001.pdf 

[2] http://www.firemodelsurvey.com/pdf/CRISP_2001.pdf 

[3] http://www.firemodelsurvey.com/pdf/FIERAsystem_2001.pdf 

Alberto Alvarez - W3

PI (2012-10-04) 
 

 

 

"Fire risk analysis (quantification of the impact)" Homepage 

Following the new PBFPD process step dedicated to the assessment of the likelihood of fire events 

susceptible to occur in defined "building-occupant" systems, the fire protection engineers (FPEs) have to 

assess the consequences of these fire events, and more precisely the impact these events would have 

on the system targets which define its performance. 

While assessing the consequences of fire events susceptible to occur in the built environment (including 

buildings, structures such as airport terminal or underground subway station or tunnels), the fire 

protection engineers (FPEs) use different types of tools. These tools can be characterized by the 

phenomena they model (fire effects including temperature profiles, smoke movement, evacuation of 

occupants and structure response to a fire) and by their level of complexity (e.g. for fire effects 

calculations: algebraic equation gathered in a procedural set, zone models, and computational fluid 

dynamics). 

In order to help the FPEs "substantiate a fire model for a given application", the Society of Fire Protection 

Engineers (SFPE) published a guide [1] in 2011, in complement of the SFPE guidelines that help the 

engineer understand the performance-based design process [2] and the SFPE guidelines which assist 

code officials in the review of performance-based designs [3]. 

Solving a fire related problem within the engineering context of performance-based fire protection design 

requires most of the time using tools characterizing the fire effects on one hand and the occupant 

evacuation process on the other hand. Due to the complexity of these phenomena, the past decades of 

research have been dedicated by scientists to model 3-D effects of fires while other scientists 

concentrated their efforts on building occupant evacuation tools. In consequence, no major effort was 

made by the community to provide guidance for FPEs to use these tools in conjunction. 

Thus, the 'test bed' environment studies seem the best opportunity for the FPE community to share 

their savoir-faire in terms of how the simultaneous processes of fire spreading and occupant evacuation 

are dealt for specific systems formed by building configurations and their occupants. 

Databases for all these types of tools dedicated to the quantification of the impact of fire events are also 

required in order to provide data applicable to specific "building-occupant" systems, in order to reduce the 

uncertainities related to the input data on the tool results. 

[1] SFPE, Guidelines for Substantiating a Fire Model for a Given Application, 2011 

[2] SFPE, SFPE Engineering Guide to Performance-Based Fire Protection, 2007 

[3] SFPE/ICC, Code Official's Guide to Performance-Based Design Review (chapter 11), Society of Fire 

Protection Engineers and International Code Council, 2004 

Alberto Alvarez - W3

PI (2012-10-03) 
 

 

 

 

 

"Fire risk analysis (quantification of the impact)" - Tools homepage 

Tools quantifying the impact of fire events have been developed separately as each of the following
 

phenomena has required its own extensive research:
 

- fire effects,
 

- evacuation of building occupants,
 

- response of the building structures.
 

Fire effects tools gather:
 

- algebraic equation sets, dedicated to the specifics of the fire phenomena such as the temperature on 

the centerline of a fire plume, temperature profiles in the ceiling jet, time before flashover in a room, 

activation time of a heat detector. 

- fire zone models, which usually divide an orthogonal space into two control volumes (i.e. a lower zone 

and an upper zone) where the temperature and the species concentrations are considered 

homogeneous. Additional zones may be considered like a plume or a ciling jet. 

- Computational Fluid Dynamics (CFD) fire models, which divide complex geometries in a large number of 

control volumes where usually a set of governing equations for conservation of energy, total mass, 

momentum and chemical species. 

Evacuation tools gather [1]: 

- movement models based on algebraic equation sets that describes the movement of people with 

hydraulic models,
 

- partial behavioral models,
 

- behavioral models,
 

- behavioral models with risk assessment capabilities,
 

- behavioral models with artificial intelligence capabilities.
 

Structural response tools gather:
 

- algebraic equation sets, which were established for the design of fire resistance of structures [2],
 

- 2D or 3D models, which calculate the evolution of the temperature in the structural elements in a fire 

introduced as the evolution of the gas temperature or a net flux on the surface of the structure.
 

[1] Erica D. Kuligowski, Computer Evacuation Models for Buildings, Section 3, Chapter 17 of the 4th 

edition of the SFPE Handbook of Fire Protection Engineering, Society of Fire Protection Engineering, 

National Fire Protection Association, 2008 
 

[2] Ulf Wickstrom, Methods for Predicting Temperatures in Fire-Exposed Structures, Section 4, Chapter 9 

of the 4th edition of the SFPE Handbook of Fire Protection Engineering, Society of Fire Protection 

Engineering, National Fire Protection Association, 2008 

Alberto Alvarez - W3

PI (2012-10-05) 
 

 

 

 

"Fire risk analysis (quantification of the impact)" - 'Test bed' environment homepage 

Objectives of the 'test bed' environment studies. 

The 'test bed' environment studies are designed to ultimately provide guidelines for the FPEs to use the appropriate 

set of tools while solving a fire safety related issue in the built environment. 

Guidelines would be established at the conclusion of each 'test bed' environment, gathering information of the 

different tools used to solve the common engineering questions, how the engineers manage to mix the results from 

different 

As a by-product of the 'test bed' environments, feedback may be given to the tool developers (who we hope will be 

an active part of the 'test bed' environment studies) in order to develop new models or improve the current ones so to 

increase the validation domains of their tools to include the ones considered in the 'test bed' environment studies. 

The organization of 'Test bed' environments 

Each 'test bed' environment is organized in three phases: 

• the pre-processing phase, 

• the processing phase 

• and the post-processing phase. 

You can help the community by either joining already defined 'test bed' environments (by looking at the list of 

ongoing projects) or setting up a new project. By clicking on either one of these links, you will be given information 

about the different phases of a 'test bed' environment. 

Besides, you can look at the different building configurations that are available for a possible new project, create a 

new project with one of these configurations or propose new building configurations so other engineers can use and 

set up new 'test bed' environment projects. 

Important related texts 

The concept behind the 'test bed environments was first introduced by Alberto Alvarez at the 2011 Fire and 

Evacuation Modeling Technical Conference, hosted by the company Thunderhead Engineering. The paper prepared 

for this conference is available with this link. 

In 2002, Prof. Brian J. Meacham presented the 'test bed' environment during the 9th International Conference on 

Performance-Based Codes and Fire Safety Design Methods organized by the Society of Fire Protection Engineers. 
 

 

 

 

 

 

 

Pre-processing phase page for a New Project 

The pre-processing phase introduces the 'test bed' environment study and therefore includes the following 

information someone designed as the Project Leader needs to provide to start a new project. Feel free to submit the 

information described below. The information will be sent to the moderator of the website in order to assess the 

completeness of the information and consequently design a specific page in the ongoing project section of this 

website. All the provided information would be made available there, and a corresponding forum will be created so 

that the project participants could exchange information on the subsequent phases of the project. 

Please fill up the different information below and upload the building layout files. 

Name of the Project Leader 

If you are interested in submitting a new topic for a 'test bed' 

environment, you are encouraged to fill up the form and submit to the 

moderator of the site for assessment and configuration of the new project 

page 

Classification of the studied system 

Specify the building-occupant type related to the main purpose of the 

building (e.g. hospital, nursing home), along with the design features 

which have an influence on the fire event (e.g. high rise configuration and 

atrium space) 

Object of the Study 

Specify here the objective of the 'test bed' environment study related to 

the considered system described above (*) 

(e.g. horizontal evacuation of a patient room floor in a hospital) 

Building layout 

For the time being, building layouts provided here for use in the 

subsequent processing phase will contain all the data architects establish 

in the design phase of a project (**). 

Please, upload here all the files related to architectural design. Common 

formats are from the software AutoCad© and Revit©(***read the 

important disclaimer) 

(*) Fire events susceptible to occur in the system and damage directly or indirectly system targets which define the 

metrics of the system performance.
 

Within a single complex building configuration, it would be possible to study numerous fire events including:
 

- the fire events themselves (e.g. study of the characteristics of a single or several fire protection measures and their
 

effects on the fire event) in that case, the 'test bed' study only deals with fire effects tools,
 

- building occupant evacuation strategies (e.g. the study of the evacuation process using elevators in high rise
 

buildings). In that case, the 'test bed' study deals with evacuation tools alone or combined with fire effects tools,
 

- structural response (e.g the study of partial or total collapse of a building in fire).
 

(**) The focus of the 'test bed' studies is related to the capabilities of the tools to describe the phenomena, with
 

knowing the maximum of information as given after the design phase of a project, so that each tool, from the simple 

procedures found in standards to the most complex, such as computational Fluid Dynamics and evacuation tools
 

simulating human behavior, can be used at their own full potential in order to the comparison to be complete.
 

Studies have been performed to compare results from tools, but for specific scenarios with the aim of determining 

and increasing the domain of validation of these tools. Studies were conducted on certain types of tools, fire effects
 

tools or evacuation tools (Lord et al. 2006). No study has been undertaken for comparing tools for specific 

engineering topics for specific systems: for example, and then(but not as engineering responses)
 

(***) By submitting these files, you make sure that the files are not copyright protected, and legally available for the 

FPE community to use.
 
 

 

 

"Fire risk analysis (quantification of the impact)" - 'Test bed' environment / Pre-processing phase page for Project 1 

Name of the Project Leader:	 Prof. Brian J. Meacham - Worcester Polytechnic Institute (USA) 

e-mail address: place email address here 

Please contact the Project leader if you wish to participate 

Classification of the studied system: 6 story High-rise Hospital, with an atrium 

Object of the Study: horizontal evacuation of a patient room floor in a hospital 

Building layout files: Link to the CAD and PDF files 

Project Initiation Date: October 1st, 2012 

Project Participants: Alberto Alvarez (Worcester Polytechnic Institute - USA, place email address here) 

Majed Almejmaj (Worcester Polytechnic Institute - USA, place email address here) 

Description of the object of the 'test bed' study 

Project 1 concerns the optimization of horizontal evacuation of a patient room floor in a high-rise general 

hospital, in case of a fire starting in a corridor of that floor. 

The objectives related to Project 1 are to: 

- insure the safe displacement of the patients susceptible to be affected by the effects of the fire 

originating in the corridor, 

- minimize the number of patients affected by any fire originating in the corridor as well as limit the 

damages to the patient room floor. 

Alberto Alvarez - W3

PI (2012-10-01) 
 

 

 

 

 

 

 

"Fire risk analysis (quantification of the impact)" - Database homepage 

Databases for tools quantifying the impact of fire events include: 

1) databases associated with fire effects tools, containing useful information from 

o fire experiments involving combustible materials located in the considered system, describing how 

these materials release heat and fire effluents with time, 

o characteristics of combustible materials, in terms of physical properties to absorb heat and ignite (e.g. 

thermal conductivity, density, heat capacity, thermal response parameter). 

When looking for heat release rates for building contents, from furniture to curtains, from appliances to 

even cars, a primary source of information is the SFPE Handbook chapter dedicated to heat release 

rates, written by Babrauskas [1]. This chapter contains numerous references that can lead to a 

significant amount of data from furniture calorimeters, including heat release rates evolution with time, 

soot and toxic component yields. In addition, by reviewing NIST publications alone, some fifty different 

experiments have already been included in a database, along with the available snapshots and videos. 

This number will be expanded by looking at more NIST studies, as well as tapping into test data from 

around the world. Before the end of the year 2012, it is planned to include this database in the Vulcan 

Intiative to get some feedback and possible contribution to the database from engineers across the 

world. 

Radiation transfer is avery important phenomenon to consider when assessing fire spread from the first 

burning item to the rest of the combustibles located nearby. 3-D fire simulators are able to model 

radiative heat transfer, which requires a refined characterisation of the flame, in terms of location and 

height. In consequence, creating Fuel Packages for 3-D simulations seems a useful task to perform so 

that FPE could directly use them in calculations using the Fire Dynamics Simulator at first. 

The fire experiment database could be found here. 

The Fuel Packages for 3-D simulations are introduced here. 

2) databases associated with the evacuation of building occupants, containing useful information 

from 

o experiments related with occupant movement in the built environment, 

o experiments related with human behavioral response to fire and smoke. 

3) databases associated with structural response of the building in case of fire events, containing 

useful information from 

o fire experiments related with the partial collapse of a , 

o characteristics of non combustible building materials, in terms of physical properties to absorb heat. 

[1] Vytenis Babrauskas, Heat Release Rates, Section 3, Chapter 1 of the 4th edition of the SFPE 

Handbook of Fire Protection Engineering, Society of Fire Protection Engineering, National Fire Protection 

Association, 2008 

Alberto Alvarez - W3

PI (2012-10-09) 
 

 

 

 

 

"Fuel Packages for 3-D simulations" homepage 

3-D fire simulators that are used as engineering tools for safety purposes, still require the user to input 

data such as the evolution with time of the heat release rate (HRR), which describes the fire from its 

ignition to its extinguishment, as well as the evolution with time of the species produced by the 

combustion of the different flammable building contents. The HRR history is assumed to be determined 

from single HRR curves established with furniture calorimeter tests and translated in time when the 

ignition of the subsequent building contents is estimated, according to a pre-established fire scenario. 

This project aims to create a comprehensive database of HRR curves for a range of combustible building 

contents so that the fire protection engineer can select the data which is the most appropriate to a fire 

protection engineer project. 

Fuel packages for 3-D fire simulators include:
 

- a 3-D geometry, which represents the spatial configuration of the combustible package, as its external
 

envelope,
 

- the description of the evolution with time of the burning surfaces of the 3-D geometry.
 

The characteristics of the burning surfaces will determine the HRR history as well as the production of fire 

effluents. 

The final product of this project is intended to create "fuel packages" to be used in the Fire Dynamics 

Simulator (FDS) developed by the US National Institute of Standards and Technology (NIST) since this 

computational Fluid Dynamics is available for free and largely used by the Fire Protection Engineering 

community. Nevertheless, it is expected that the 'fuel packages" will be described with enough details that 

they could be used for other CFD fire simulators. 

The advantage of having discrete "fuel packages" for 3-D simulations is to be used by Fire Protection 

Engineers to estimate the ignition of secondary fuel sources located nearby the 'fuel package' on fire. 

Ignition of secondary fuels is mainly dependent on the thermal radiation received by these fuels. The 

received radiation is a function of the distance between the two types of fuel sources and the power of the 

radiative "fuel package" emitter. 

Insert new figure here (when it is available). 

The figures below present an example of the process followed in order to implement the ‘combustible 

package’ database, for a mattress ignited at its center. The 3-D Fire Dynamics Simulator (FDS) from 

NIST has been used to recreate this experiment. 
Evolution with time of the Heat Release Rate of a mattress with central ignition 

On the left: experimental data extracted from a NIST resource 

On the right: comparison between the experimental data and a FDS simulation 

In addition to the HRR curve, the database gathers information related to the dimensions of the 

‘combustible package’, the applied ignition source, videos or snapshots of the experiment showing flame 

spread, evolution with time of the fire effluents. 
 

 

Snapshots of an experiment involving the combustion of a mattress with central ignition (source: NIST) 

From left to right: at 90 seconds, at 120 seconds, at 210 seconds, at 300 seconds 

Snapshots of the corresponding FDS simulation at the same moments (200 kW.m-3) 

Productions of fire effluents (toxic and irritant products) as well as soot are data required for assessing 

toxicity and loss of visibility during fire events. FDS allows the use of ‘burners’ which can also emit 

species such as HCN, CO2, CO, HCl and soot, as a function of time, specified by the user. Some of the 

furniture calorimeter experiments contain this data. For these ‘combustible packages’, the data will 

include fire effluent productions (in over-ventilated conditions and under-ventilated conditions when 

available) as well as the HRR curve. 

Nevertheless, it should be noted that the data related to fire effluent production is sparse. It is often given 

as a global mass yield (i.e. mass of a considered fire effluent produced, divided by the mass of fuel 

consumed), or as a global CO/CO2 ratio as this parameter is an indicator of the ventilation conditions. 

In absence of fire effluent data for a ‘combustible package’ from furniture calorimeter tests, data gathered 

from cone calorimeter tests or other laboratory-scale tests may be considered. 

A list of collected experiments that could be used to set up packages is located here. 
"List of collected furniture test experiments" page

Twin Size Bunk Bed 

Twin Size Mattress 

Twin Size Mattress 

Kiosk 

Small Dresser 

Workstation 

Workstation 

Sofa NIST Fire test 

Loveseat NIST Fire Test 

Wooden Pallet NIST Fire test 

Chair 

Chair 

Chair 

Chair 

Loveseat 

Sofa 

Chair 

Chair 

Chair 

Chair 

Chair 

Chair 

Loveseat 

Sofa 

Sofa 

Sofa 

Sofa 

Sofa 

Sofa 

Sofa 

Sofa 

Bookshelf 

Bookshelf 

Bookshelf 

Bookshelf 

Wires 

Wires 

Wires 

Wires 

TV Cabinet housing (NFR) 

TV Cabinet Housing(FR) 

Business Maching Housing (NFR) 

Business Maching Housing(FR) 

Kiosk-open shelved 

Kiosk-closed shelved 

Metal Wardrobe 

Metal Wardrobe 
Plywood Wardrobe 

Plywood Wardrobe 

Plywood Wardrobe 

Particleboard Wardrobe 

Plywood Bookcase 

Mattress 

Mattress 

Mattress and box spring 

Mattress, no box spring 

Mattress, Twin size 

Mattress, Queen size 

Mattress, King size 
 

 

Building Configurations Homepage 

This page contains building configurations that have been collected independently of any 'test bed' studies but could 

be used for future projects as they are free from any copyright and as they represent potential interesting buildings of 

interest. 

In case you have building configurations you would like to share with the Fire Protection Engineering community 

for future 'test bed' studies, feel free to fill up the form at the bottom of this page. 

Building configurations Image(s) 

High Rise Historic building (Hall of Justice) 

High-rise office building 

Science Building 

Dormitory (2 wards with a common space at the junction) 
"Evaluation of the integration of the fire protection measures in the system " Homepage 

The fire protection measures considered in the fire risk analysis steps for their benefits in reducing the 

effects of fire events upon the overall performance of a "building-occupant" system. 

Fire Protection Engineers (FPEs) need to evaluate how these fire protection measures are integrated in 

the system, so because of the challenges related to the maintenance and the possible changes of the 

building use once the design phase and the construction phase are done. This 5th important step of the 

new PBFPD process is performed in order minimize the incompatibility of the fire protection measures 

with the components used in an everyday basis. In other terms, this step assesses the fire protection 

measures, which are the most efficient according to the fire risk analysis, are not counter-productive and 

therefore ignored or worse rejected by the system, ultimately rendering them inoperative during an actual 

fire event. This step goes beyond the documentation on how the fire protection measures are designed, 

installed and maintained in the current PBFPD processes. 

Tools such as the ones elaborated for system dynamics could be valuable to perform this new PBFPD 

process. 

Databases are required to gather elements of the system functionality including contingency plans 

established to deal with emergency situations. 

'Test bed" environments are built so to consider the specificities of "building-occupant" systems and 

their related fire event issues. 

Alberto Alvarez - W3

PI (2012-10-03) 
"Cost-benefit analysis" Homepage 

To be completed
 

Tools such as the ones elaborated for establishing a cost-benefit analysis of system components could 

be valuable to perform this new PBFPD process.
 

Databases are required to gather.
 

'Test bed" environments are built so to consider the specificities of "building-occupant" systems and their
 

related fire event issues.
 

Alberto Alvarez - W3

PI (2012-10-03)