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FiRE-TECH Fire Risk Evaluation To European Cultural Heritage

Fire Risk Evaluation to European Cultural Heritage

WG7

Define, apply and document a quantitative method to help decision-

making

Final report

May 2005

Convenor: CSTB Project team: CSTB, IBMB Other Participants: RUG, WFR, IST, TNO

Authors Michel Curtat, Dr. Sc. - CSTB Prof. Dr. Ir. Paul Vandevelde, Prof. Ir. Arch. André De Naeyer, Ir. Emmy Streuve - UGent Ir. Leen Twilt, Arnoud Breunese M. Sc. - TNO Prof. Ildefonso Cabrita Neves, Prof. Joaquim Valente, Prof. João Ventura - ST

FIRE-TECH WG7Final report, CSTB, May 2005

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TABLE OF CONTENTS

1. DECISION MAKING IN FIRE-TECH.................................................................. 4 1.1 Introduction ............................................................................................. 4 1.2 Main features of approaches on help to Decision Making .......................... 4

2. LOCATION OF DECISION-MAKING IN THE WHOLE UPGRADING PROCESS ......................................................................................................... 7

• Phase 1. Preliminary steps .................................................................... 7 • Phase 2. Analyse the present level of safety and protection .................. 8 • Phase 3. Possible actions to improve safety and protection .................. 9 • Phase 4. Decision Making (WG7)......................................................... 10

3. HIERARCHY METHODS AND TOOLS........................................................... 12 3.1 Main features of the hierarchy methods ................................................. 12 3.2 Qualitative aspects of the hierarchy network.......................................... 13 3.3 Various naming of the network rows in hierarchy methods..................... 14 3.4 Choosing actions and weights in a hierarchy approach ........................... 15 3.5 Steps of the calculation in a hierarchy approach .................................... 17

4. CSTB ALADIN DECISION MAKING TOOL .................................................... 20 4.1. Bases of the model ALADIN.................................................................... 20 4.2. Quantitative aspects of ALADIN............................................................. 20 4.3 Running ALADIN programme. User’s guide. ............................................ 21 4.4 Examples of runs with ALADIN ............................................................... 21

4.4.1 Simple illustrative example ..................................................................................................................... 22 4.4.2 More realistic example............................................................................................................................. 23

4.5 Using ALADIN for practical applications.................................................. 25 4.6 Example of a study with ALADIN for comparison of 3 alternatives .......... 26

5. THE IST COST/EFFECTIVENESS SPREADSHEET ...................................... 34 Index hierarchy methods.............................................................................. 34 5.1 Introduction ........................................................................................... 35 5.2 Input ...................................................................................................... 35

5.2.1 Policy ....................................................................................................................................................... 35 5.2.2 Objectives ................................................................................................................................................ 36 5.2.3 Strategies ................................................................................................................................................. 36 5.2.4 Fire safety measures ................................................................................................................................ 37

5.3 Scores and weights ................................................................................. 42


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5.4 Grades of implementation of the fire safety measures ............................ 47 5.5 Costs associated to the implementation of each class of fire safety measures. ..................................................................................................... 49 5.6 Output.................................................................................................... 50

6. OPTIMISATION OF COST /EFFECTIVENESS............................................... 61 6.1 ALADIN APPROACH ................................................................................ 61 6.2 Application made by TNO using the first version of the IST COST/EFFECTIVENESS spreadsheet ............................................................ 63

7. CONCLUSIONS ON HELP TO DECISION-MAKING...................................... 69 ALADIN......................................................................................................... 70 The IST COST/EFFECTIVENESS spreadsheet ............................................... 70 Final comments............................................................................................ 71

8. REFERENCES................................................................................................. 72

ANNEX 1. OTHER DM APPROACH: B. ROY ET AL.............................................. 73

ANNEX 2. AHP (ANALYTIC HIERARCHY PROCESS) .......................................... 74 A2.1 Concepts of AHP................................................................................... 74 A2.2 Theory and Methodology of AHP........................................................... 75

A2.2.1 Weighting influences ............................................................................................................................ 75 A2.2.2 Construction of matrices by pair-wise comparison............................................................................... 76 A2.2.3 Consistency Ratio (C.R.) ...................................................................................................................... 77

A2.3 Other AHP method: Hierarchical Cross-Impact Analysis ....................... 78 A2.4 Previous Applications of AHP to Fire Safety and Fire Protection .......... 79 A2.5 Research under work in AHP Methods .................................................. 80

ANNEX 3. CULTURAL HERITAGE FIRE RISK INDEX METHOD .......................... 81 A3.1. A Fire Risk Index for Cultural Heritage................................................ 82

A3.1.1 Development of a risk index method .................................................................................................... 82 A3.1.2 Generalised procedure .......................................................................................................................... 83

A3.2 Fictive example cultural heritage risk index method. ........................... 84 A3.3 Conclusions.......................................................................................... 88


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1. Decision making in FIRE-TECH

1.1 Introduction

People have always had to make decisions. A lot of important decisions were made during

the History (war or peace, rising taxes, etc.), and many smaller decisions are made in

everyday life (e.g. buying a new car or a dwelling is a multi-criteria problem with a strong

cost/effectiveness aspect). A first scientific approach of Decision Making was realised in the

19th Century by mathematicians and economists, such as Pareto, Morgenstein, etc. These

first approaches were dealing with decision problems depending on one criterion and one

variable: they had to solve monocriterion decision problems. Multicriteria problems were

addressed in the middle of the 20th Century (Koopsman, Kuhn & Tucker, etc.). The question

was to rank a set of alternatives (each of them based on the same variables having different

values) or to find the best alternative in the set. The first international conference in Multiple

Criteria Decision Making (MCDM) was organised in 1972 and followed by many research

projects. We have now a lot of works done on MCDM or MCDA (Multiple Criteria Decision

Aid), where the decision making procedure is based on different theoretical basis (utility

based [Fishburn], overranking [Roy], etc.). We chose in FIRE-TECH the hierarchy approach that offers the capability of weighting (grading) in simple way alternative solutions of safety/protection actions.

The words: "Decision-Making", "Decision Analysis", "Help to Decison-Making", are more and

more used, mainly in the domains of human activities connected with management,

business, allocation of resources ... The concepts, tools and methods mentioned in many

papers are various, more or less complex and partially validated. Application to Fire Safety

and Fire Protection is recent and still rare.

1.2 Main features of approaches on help to Decision Making

• The selection of the best alternative or a ranking of all the alternatives is aimed.

• Inefficient alternatives must be eliminated.

• The identification of the most promising alternatives can be done solving a mathematical

programming problem.


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• The solution must be: not too much influenced by the uncertainty of the results of the risk

analysis step, nor by slight variations of the weights given as inputs.

Explaining the general engineering decision making process, Krick (1969) states the

following:

“Although the specifics vary from situation to situation, in almost every instance these four

steps must be taken before an intelligent decision can be reached:

• Objectives, strategies and measures, the “criteria” (presented below) must be selected

and their relative weights determined.

• The performance of alternative solutions must be predicted with respect to these criteria.

• The alternatives must be compared on the basis of these predicted performances;

• And then, a choice must be made.”

Within the FIRE-TECH programme dealing with the optimisation of fire safety and fire

protection in Cultural Heritage, we have developed an approach presenting the following

characteristics:

• "Help to Decision-Making" has in Fire-Tech to be understood very widely, i.e. we think of

bringing to a person in charge of fire protection of a Cultural Heritage any kind of help

FIRE-TECH may deliver. In other words, we are not thinking of considering only the

"decision analysis" task, to be performed when all the technical and economical elements

of knowledge has been gathered, but of all the steps from the very intention of evaluating

or improving the level fire safety to the final actions of renovation, equipment,

organisation, ...

• Methods and tools should not be very complex, for several reasons:

- the final user may not be able to use an expensive approach as she or he will may have a limited amount of money and a too short time available;

- the basis of method and tools have to be understood by the persons who will do the work.

• Method and tools have to have been experimented and validated. Because of the novelty

of the Decision-Making approaches, some of the complex approaches are still in their

development state; These approaches need more research work before practical

application.


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• The Decision-Making part of the process has to offer the following characteristics:

- Be based on a quantitative approach

- Give a general view of inputs and outputs

- Rank alternate solutions

- Optimise efficiency/cost

- Be open to more complex approaches.

The Decision-Making approach retained in FIRE-TECH is based on the “hierarchy analysis”

that uses a decomposition of the main goal in “sub-goals” at several levels below the goal top

level. At each level, several “boxes” corresponding possible actions at this level are graded

for each box at the upper level (more “general”). These grades, or weights, express the

influence of a row on actions of the upper row. We assume that the influences are linear.

Then matrix or linear combination formulae are used to calculate the dependency of any box

on any other box below it. The § 3 presents the hierarchy analysis and the tools developed in

FIRE-TECH.

The following chapter § 2 present the location of the Decision-Making task in the whole process. The hierarchy approach, retained here, is described in chapter § 3.

The tools developed for FIRE-TECH, CSTB ALADIN programme and IST Cost/Effectiveness spreadsheet, are presented in chapter § 4 and chapter 5 respectively.

Chapter § 6 exposes the way the important question of optimisation of the ratio EFFECTIVENESS/ COST was addressed with ALADIN and with the IST Cost/Effectiveness spreadsheet.

ANNEX 1 gives a few words on the overranking Decision-Making methods.

ANNEX 2 brings details on Analytic Hierarchy Process.

ANNEX 3 presents the “Cultural heritage fire risk index", by Fredrik Nystedt.

NB: This report was written after several case studies had been realised (WG 8).It takes into

account comments made by FIRE-TECH partners. The case studies themselves offer the

opportunity to look at the way the tools: IST spreadsheet or ALADIN, both presented below,

have been applied.


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2. Location of Decision-Making in the whole upgrading process

WG7, in collaboration with other WGs, proposed a general frame and definitions of the

phases and steps of the general cost-effectiveness study (WG7 draft report,”Presentation of

the fire-tech method to help to decision-making in fire protection of cultural heritage”,

February 2004, Michel Curtat). The global approach was re-formulated after some minor

modifications and largely illustrated by several case studies in the WG8 report (September

2004). The location of the Decision-Making actions in the whole process is clearly presented

in Figure 2: flowchart of the effectiveness / cost study, commented in details in the

WG8 report.

The following lines give comments on the phases of the whole process of improvement.

• Phase 1. Preliminary steps

Phase 1.1. What is awaited at the end?

The goal of the work has to be fixed at the very beginning. It is useful too to know what are

the reasons to perform an upgrading of the level of safety and protection of the Cultural

Heritage, e.g.: is it a general care for the improvement of the protection of the contents, or is

there a new standard or a new regulation, or did a recent fire show a special need of

protection, or does the authority in charge of the Cultural Heritage have a new policy in

safety …?

It is useful too to have exchanges with the persons who are asking for the study (a safety

commission, a Cultural Heritage authority, the Cultural Heritage manager …) and with the

persons making the final decision and the persons in charge of the financing.

Phase 1.2. Definition of time and money available

The awaited duration of the study as well as the money available for the study and for the

improvement (renovation, new equipments …) have of course to be known. Several

alternatives on the improvements funding and delay may be presented, e.g. if several steps

of the improvements can be considered on several years. In this later case, priorities of

actions have to be established with the Decision-Making tools.


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• Phase 2. Analyse the present level of safety and protection We have distinguished here two approaches, even if the best way is to use both of them:

a “prescriptive and expert approach” and a “performance based approach” based on fire

safety engineering.

Phase 2.1 Prescriptive and expert analysis

• Experience of previous fires

The knowledge of previous fires in a similar C H can be used to suggest fire scenarios

and/or, directly, lead to possible solutions of protection, the efficiency of which having been

demonstrated. Information on previous fires in Cultural Heritage has been provided by

WG2 report.

• Behaviour of ancient materials

Knowledge gained on the characteristics of ancient material can be applied to find frail

elements in the Cultural Heritage, and bring ideas of protection at step 3. The work done in

WG3 brings information on the behaviour of these particular materials.

• Observation and collection of comments from everyday life of the Cultural Heritage

It might be very efficient to gather comments and observations on the behaviour of the

Cultural Heritage, mainly on the occurrence of small incidents or on the discovery of “weak”

aspects. Such a qualitative analysis is an important part of this step.

• Complying to regulations and exchanges with authorities

The persons in charge of Fire Safety of the Cultural Heritage have to know the regulation

concerning the Cultural Heritage. Compliance to existing regulations is very important. Even

if a Performance Based Study is carried out, it has to be executed within a regulatory frame.

WG1 has presented a global view on the European regulations dealing with Fire

Safety/Protection in Cultural Heritage.

The compliance of any new action of improvement the fire safety or protection level has to

be checked.


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• Expert analysis

Expert judgement, exploitation of results from tests, knowledge from fires in various

conditions …, can bring an important contribution to this phase.

At this step, we could add the possibility of considering advises given in some cases by

associations or authorities.

Phase 2.2 Performance based Quantitative Risk Analysis

Construction of scenarios and fire simulation with computer fire ‘fire, smoke, egress …)

models is very useful as it can give more light or bring a new insight on some difficulties

occurring at certain times. It brings a quantified view of the unwanted consequences, at

which time some unacceptable state is reached, and informs on the speed of fire

aggressions. Fires simulations can show the efficiency of suggested new measures, by

showing the differences in conditions of hazards.

The choice of realistic scenarios and an estimation of their probabilities have to be realised

by an fire expert.

FSE models can then be used again to evaluate the efficiency of possible actions. WG6 has

presented the method and tools of the Risk Analysis step.

• Phase 3. Possible actions to improve safety and protection

After the previous phase, a list of acceptable measures has to be produced, accompanied

with characteristics and cost of each measure. The decision-making tools will help to choose

in this list the most convenient measures. Depending on the Cultural Heritage, on the goal

and nature of the study, a few possible actions can be well defined, or, at the other hand, one

may still have a view on a large variety of them. Two models, presented below, ALADIN and

the IST Cost/Efficiency spreadsheet, are the tools developed in Fire-Tech. ALADIN seems

to be more adapted for the 1st case, the IST Cost/Efficiency spreadsheet for the 2nd case (see

below § 4, § 5, § 6).

Phase 3.1. Possible technical actions (measures)

Once points where improvements are needed have been identified, it is necessary to know

what the possible technical solutions are, what are their costs, efficiency, reliability, etc. WG

4 wrote a report containing such useful information, and presenting a large list of technical

measures.


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Phase 3.2. Possible non technical actions (measures)

A number of measures are not merely technical: emergency planning, teaching and training

employees, salvage operation management, organisation of local fire-fighting, conception of

signs, etc. The effectiveness of these actions can be evaluated by expert judgement and/or

by Fires Safety Engineering.

• Phase 4. Decision Making (WG7)

We are then at the point where several safety or protection alternatives are to be evaluated.

Decision-Making tools will then be used to choose one of them, or in order to rank them

either to keep one pf them, or to establish priorities for an improvement during several

years. The present report brings information on the method and on two tools used for

applications to case studies: the ALADIN programme and the IST “cost/effectiveness index”

spreadsheet.

UGentIr. Emmy Streuve ©

PHASE 2: Analysis of present level of safety

Performance BasedAnalysisPrescriptive Analysis

1. Performancecriteria

3. Riskanalysis

event trees

2. Developdesign

fire scenarios

Objectives Acceptancecriteria

Selectionoffire scenarios

Design fire scenarios

Building characteristics

Occupancecharacteristics

Risk level

Fire curves: Quantification of fire development

Analysis of damage

Selectionevents

Selectionfire safety

design

Prescriptivein the

Existingregulations

Informationout of

previousfires

Guidelinesonthe firebehaviourof ancientmaterials

4. Risk evaluationPHASE 3: Possiblefire safetyactions

Prescriptivecritaria for fire

protectionaction

Selected firesafetydesign meets

the performance criteria?

Figure 2.1: Analysis of the present level of safety and protection.


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Figure 2.2. Flowchart of the cost /effectiveness study.

Cost effectiveness study

Phase 2:

2’. Prescriptiveanalysis

2”. Performancebased analysis

2. Analysis of present level of

safety

3. Possible fire safety actions

1. Preliminary steps

1.1. Definitionof main goal

1.2. Time &money available

4’. Technical optimisation

4”. Technical& financial

optimisation

4. Decision making

Phase 3:

Phase 4:

Approach 1 Approach 2

Approach 1 Approach 2

UGentIr. Emmy Streuve ©


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3. HIERARCHY METHODS and TOOLS

Hierarchy approaches were retained here as decision-making tools because they seemed

simply consistent with the whole process and because they do not imply heavy calculation.

As other Decision-Making methods, the hierarchy approaches:

- Facilitate the development of logical hierarchical structures for complex decisions,

- quantify the efficiency of assessments and expert’s opinions,

- assign weights (importance of influence) to different possibilities relative to one another:

ranking a set of alternatives in order to retain the most appropriate one(s).

3.1 Main features of the hierarchy methods

A general question is addressed, the goal of the decision making, depending on several

variables, and for which several alternative solutions can be imagined and have to be

retained, ranked, or eliminated.

The decision problem is decomposed in several “possible actions” at different depths of

analysis, from global goals to precise solutions of partial aspects.

At each level of “generality”, a judgement is made on the relative efficiency of each

component of this level on each component of the levels above.

Calculations are executed with linear models of indirect influences.

The outputs are the relative influence of all the components are calculated so that the best

solution(s) (the best alternative) can be identified and weighted, or a ranking be established.


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3.2 Qualitative aspects of the hierarchy network

Table 3.1. Levels (rows) of the hierarchy network

• Policy = main goal

• Objectives

• Strategies (or: tactics)

• Measures (or: components, or: parameters)

• (Grades, in some approaches)

The main goal of the decision to make is at the top level of the hierarchy. Policy is this

very general goal. We have one policy. Here we can call it: “Reduce fire risks” or

“Optimise fire safety/protection”. These words are written in a single box at the first

(upper) level.

The levels below the top contain “actions” one can think of for the success of the policy.

These actions are described more and more precisely as we go down the levels.

Objectives are the actions directly connected to policy. They are mentioned at the

second (lower) level in a few boxes. They are called, e.g.: “Protect the firemen”, “Protect

the precious contents”, ”Safeguard continuity of activity”, …

At the third level, several boxes contain the Strategies. Strategies are actions necessary

to reach the objectives. E.g.: Reduce the probability of fire start», «Limit fire

development”, “Facilitate egress”…

Measures (or: parameters) are described at the fourth level in a certain number of boxes.

Measures are “practical” solutions to serve the strategies. E.g.: “Means for fire detection”,

“Means for fire suppression”, “Systems of smoke control”, “Emergency and alarm

signs”…


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A list of measures can be established from expert knowledge. Such a list, proposed in

WG7, is given in the presentation of ALADIN (Chapter 4). The IST cost/effectiveness

index spreadsheet contains another list of 19 measures that was established during the

development of this tool. It is presented below (Chapter 5). The weight a measure can

receive is of course depending on the characteristics of the cultural heritage being

studied and on the fire scenarios.

Grades may be introduced at the lowest level in “index methods”, as guiding values to

help to the choice of a measure. E.g., a list of fire resistant partitions can be given with

values assessing their relative efficiency. Each grade is associated with one measure:

using grades is a way to assess a measure within the global calculation. ALADIN uses no

grades (or we can say that grades = 1 in ALADIN). Further weighting of the efficiency on

alternatives is possibly realised on the outputs of ALADIN

3.3 Various naming of the network rows in hierarchy methods

Close hierarchy methods are using different words for the rows in a hierarchy network. The

following Table 3.2 aims at the presentation of the different terms used.

Table 3.2. Words for Quantitative aspects and outputs

Level In papers by Saaty, Marchant, Shields

Vocabulary of Dublin University

In FIRESEM

(Annex 3)

In Fire Tech

1 (top)

Policy Main goal Policy Policy

2 Objectives Criteria Objectives Objectives

3 Tactics Sub-Criteria Strategies Strategies

4 Components Sub-sub-criteria

Or: decision units

Parameters Measures

5 Sub-components (possibly)

Survey items

Grades for measures


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In hierarchy approaches:

- Each box receives given values according to the relative influence of all the boxes in the

row above. “Relative” means that the figure is expressed relatively to the other boxes of

the same level.

There are several ways to calculate the weights from levels and boxes: either direct explicit

calculations when it is possible, or matrix calculations.

- The calculations are made by summation of combined influences (see the IST

cost/efficiency index spreadsheet) or by a matrix calculation (see ALADIN).

Details are given in the following paragraphs.

3.4 Choosing actions and weights in a hierarchy approach

Definition of all actions and weights is based on existing knowledge about the various

components that play a role to improve fire safety and fire protection. The choice of the

values of the relative influences of “boxes” at level l+1 to each box of level is of course an

expert’s work, depending on the characteristics of the study being carried out. Among the

criteria for choosing possible actions, we find: performance, suitability, reliability, architectural

acceptability …

Another important aspect is that the following conditions have to be fulfilled (for each given

Cultural Heritage):

- The list of possible actions has to be as complete as possible;

- To avoid bias in the calculated influences, the concepts behind all the actions at the

same hierarchical level have to be clearly different. In other words, the intersection of the

semantic contents of any pair of boxes present on the same line must be empty.

Choice of objectives The user may be interested in one objective, e.g. the protection of the contents. Then the

user will put 1 into the “contents” box, and 0 into the other boxes (in IST Cost Effectiveness

Index spreadsheet), or will not create these useless other boxes (in ALADIN). The user may

e.g. be interested both in “contents” and in “safety for people”, and then give e.g. 0.40 to

“contents” and 0.60 to “safety of persons”.


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Choice of strategies The user defines the strategies he is thinking of (in ALADIN) and gives values into the

corresponding boxes (in ALADIN and in the IST Cost Effectiveness Index spreadsheet). In

the IST Cost Effectiveness index spreadsheet, a list of strategies is offered. The boxes

corresponding to rejected strategies receive the value 0.

Choice of measures The same can be said for measures: in the IST Cost Effectiveness Index spreadsheet,

values are to be given into pre-existing boxes, in ALADIN one has to create the boxes

corresponding to the retained measures and put numbers into them.

General lists of possible measures are presented with ALADIN and the IST Cost

Effectiveness Index spreadsheet.

The large diversity of fire conditions does not make possible the establishment of

“recommended” measures for a given Cultural Heritage. The risk analysis step is a very

useful step to help the derivation of a list of possible measures as this step underlines the

weak points of the cultural heritage.

The WG8 report presents also an example of grading possibilities for technical measures.

Then, even if the measures and the associated weights have to be fixed for each Cultural

Heritage for each given protection/safety goal, the work done in FIRE-TECH brings helps to

choose them:

- The quantitative risk analysis and/or qualitative analysis phases show weak points for

which strategies and measures can be imagined;

- The knowledge from previous fires, from WG2 report and other sources, gives

information to the efficiency of measures.

- The WG4 report describes many technical measures and gives precious comments

on them.

- The WG8 case studies present examples of possible solutions.


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3.5 Steps of the calculation in a hierarchy approach

As we said, direct influences are graded by the user who gives values as input data.

The other, “indirect”, influence grades are calculated as presented at Figure 3.1, in which

the presentation uses matrix products.

The results can also be expressed by the linear formulae corresponding to these matrix

products. The only difference from the following Figure is that we use in Fire-Tech the word

“measure” instead of “parameter”.

Figure 3.1. Schematic summary of the hierarchical approach (Watts, 1995).

(See also Figure A2.3)

The following lines give details on the required inputs and the calculated results in output.

The following figures present, on an example of network, the nature of the required inputs

and of the outputs.

The following chapters on ALADIN and on the IST Cost-Effectiveness spreadsheet will

present several examples of quantitative results.


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• Policy Improve fire safety & fire protection of the CH

• Objectives

e.g. protect persons, protect contents, protect surroundings …

• Strategies e.g. reduce probability of fire start, facilitate fire fighting and salvage, …

• Measures e.g. means for detection, facilitate access …

• Parameters (possibly) grade efficiency of each measure

M

P

M

P

M

P

M

P

M

P

M

P

P

O O O

S S S S

Figure 3.2. Example of a hierarchy network.

Parameters can be used (IST spreadsheet), or not (Aladin), according to the way the user

wants to exploit the results. With no parameter, a relative assessment of the influence of the

considered measures is made. With parameters, one can calculate an “absolute” index of

effectiveness, directly connected to the linear combination of the grades given to

the measures.

Required inputs (figure 3.3) : the user has to give the weights of each mesure on each

strategy, the weights of each strategy on each objective and the weights of objectives on

the policy.

Outputs : they are presented at figure 3.4. we obtain the weights of strategies on policy, the

weight of measures on objectives and the weights of measures on policy.

Pratical examples are given in the following pages.


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M

P

M

P

M

P

M

P

M

P

M

P

O O O

S S S S

S S S S

P

O O O Objectives on Policy

Strategies on Objectives

Measures on Strategies(Only M(j)/ S(2) represented)

Figure 3.3 Examples of inputs.

O O O M M M MM M

Measures on objectives S

M M M MM M P

Measures on PolicyO S

S S S S P

Strategies on Policy

O

Figure 3.4 Influences obtained as Outputs.


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4. CSTB ALADIN Decision Making Tool

4.1. Bases of the model ALADIN

The basic concepts are the same as in AHP (cf. Annex 2). In order to produce a tool simple

to use with fast calculation time, we use here fully consistent matrices, i.e. we always have

exactly: aij = 1/aji in matrix A. Then we assume that the expert using the programme gives

directly the weight of each box on level l+1 to each box of level l, relatively to the other boxes

of level l+1. This has to be done for all the boxes.

The definitions of policy, objectives, strategies and measures are fully open in ALADIN.

Chapter 6 presents the definitions used in the IST Cost/Effectiveness spreadsheet that can

of course be used too with ALADIN. But for a simple problem, the number of row and boxes

can be much reduced when using ALADIN (in which one cannot consider more than 6

measures at a time).

4.2. Quantitative aspects of ALADIN

Let us take the example of the box number (l,n) at level l. We consider that this box is

connected to all the boxes at the lower level l+1. Each link is given (by the user) a value. This

value represents the weight of each box number at level l+1 on the box number (l,n) at level

l. If the influence of the action described in a box of level l+1 is negligible relatively to the

other links starting from level l+1, the weight is set to 0. If the influence of the action is strong

relatively to other actions of the same level, the number is higher. The numbers are

normalised so that the sum of all the weights from row l+1 the box number (l,n) be 1 (100 %).

We suggest using the scale proposed by Saaty, given above in Annex 2.

In order to:

• avoid a too heavy work in entering input data,

• lead the user to keep a limited number of really appropriate actions (measures) or group

of actions (of measures), keep enough legibility to the outputs, we fixed in the programme

the following limits:

- the numbers of rows is limited to five,

- the number of boxes in a row was limited to six.


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4.3 Running ALADIN programme. User’s guide.

ALADIN is a FORTRAN 90 programme developed at CSTB by Michel Curtat and Christine

Jourdain. Running ALADIN is very easy: one has just to answer simple questions. The

computer time is not visible on a modern computer.

Input data

• The programme asks the following input data concerning the structure of the networks:

- How many rows (the levels)? One can use all the set of levels presented above (from

policy to measures), or as well work on a simpler hierarchy corresponding to the

actual problem.

- From the second row (the first row is the single top box, the policy) to the last (lowest)

row, how many boxes?

• The programme asks for the input weights:

- In each row (from the lowest level), and in each box in each row, what is the weight of

any box to each given box of upper level? (See also § A2.2). We use the scale: 0, 1,

3, 5, 7, 9.

The sums of the values for each row are normalised to 1 (100%) after the inputs have

been given.

Output data

• A drawing of the network with numbers given to the boxes.

• For all boxes: all the given and calculated weights.

The computer time is very short.

4.4 Examples of runs with ALADIN

We have chosen to present here examples studied with Christine Jourdain in her Master’s

report. This report (in French) presents ALADIN and gives several other examples. The first

two examples given here are aiming at the presentation of ALADIN’s results in order to help

the understanding of the inputs and outputs and of the way ALADIN calculates the influences

These examples are not directly useful any application to a study of the fire safety of a

cultural heritage. The third example comes from the WG8 case study “Virtual museum”.


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4.4.1 Simple illustrative example

In the Table 4.1 below, the weight 0.0001 means “no influence”. The number zero is not

used because it leads to problems of “division by zero”. Values of 0.01, 0.001 seem to be

acceptable too. In the present version of the programme, when the user enters 0, the

programme takes 0.001.

Table 4.1 Weights of influence.


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4.4.2 More realistic example

Figure 4.1. Structure of the network on Fire Safety/Protection imaginary case.


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Table 4.2 Calculated weights

Figure 4.1 shows the hierarchy structure for an “academic” fire safety/protection study. The

thickness of the arrows is proportional to the given input weights (from 1 to 9).

Table 4.2 gives all the influence weights. The representation is “box to box” and the “steps”

correspond to the levels: step 1 is the top (policy), the objectives box, and the strategies

boxes. The measures boxes (9 to 14) are labelled on the first column only as they have no

lower level.

Comments for this example of calculation: Inert gas, access to firemen and fire protection of

the structure represent 66 % for the protection of the historical content. For protection of

people, access to firemen represent 47%. Separation (creation of compartments) is the

strong factor.


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Sensibility analysis

The short calculation time of ALADIN authorises the users to perform sensitivity analysis: this

can be very useful in situations where they are not very confident in a given weight.

In the Master’s report by Christine Jourdain, a sensibility study was realised in order to show

how variations of the given weights can influence the conclusions. As the calculation is

based on matrix algebra, the propagation of small numerical variations is linear and does not

lead to dramatic effects on the outputs.

It is not realistic to enter close numbers, differing e.g. by 1 %, even if the programme itself

will show slightly different outputs, because the difference between the corresponding

options is meaningless if compared to the uncertainty of all the other steps of the whole

process: expert judgement, fire modelling, etc. We decided to keep the scale by Saaty given

in Annex 2.

4.5 Using ALADIN for practical applications

- ALADIN can follow the decomposition presented above on: “policy, objectives, strategies,

measures”. ALADIN was not conceived to deal with many measures and/or many

strategies, as the maximum number of boxes in a row is 6. ALADIN can be used for

“zooming” on partial influences, e.g. in using it on a reduced “one given objective,

strategies, measures” network.

- It is often necessary to weigh the global influence of a set of components of a given fire safety system, rather than weighing each individual component separately. ALADIN can be used to calculate e.g. the combined weights on policy and

objectives of given strategies and measures, as well as to compare the combined

weights of several alternatives (established by one hesitating person or by several

experts).

- The results can be presented under the format of a decision matrix that can be exploited

directly by user or can be studied with overranking tools [B. Roy et al.]

- ALADIN has been used in several WG8 case studies (cf. WG8 report).


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4.6 Example of a study with ALADIN for comparison of 3 alternatives

(WG 8, CSTB case study: “Fire protection of a virtual museum of modern art”)

In this case, the decomposition is very simple. The lower third row is “measures”, the second

row is “objectives” and the first one box row is “Fire Safety”. We have directly connected the

“measures” level to the “objectives” level. This simplification makes the numerical results

more legible. If the Cultural Heritage was more complex (here it is limited to one room and a

corridor connected to a restaurant), or if the expert(s) was (were) not able to retain a few

measures only, ALADIN can be applied on several simpler “subproblems” or one can use the

IST tool where many measures are considered. In the WG8 reports on case studies, other

more complex examples are given. Figure 4.2 presents the simple network of this case

study, with arrows for the example of “protection of contents”.

Figure 4.2: the hierarchy network for the case study of a virtual museum


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Tables 4.3 and 4.4 present the set of measures on which the 3 experts agreed as being

possible, but to which they did not associate the same weights. This list comes from expert

judgement that may have been helped by a knowledge on previous fires, application of Fire

Safety Engineering. The measures considered are convenient are the following:

- fire detection close to the artworks (“local” detection),

- sprinklers,

- water mist system,

- smoke detection,

- mobile shutter, ”curtain”,

- formation and training of the staff.

At this step, the acceptability and reliability of the measures have not been considered. It will

be assessed later, at the phase of optimisation of cost/efficiency.

Table 4.3. Possible measures.


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The experts had then to enter weights for each measure, and later for each objective. This is

given at Table 4.4 where values are not yet normalised.

Table 4.4 Input values for measures

Table 4.5. Input values for objectives

Expert Safety/protection {contents} {persons} {building} 1 1 1 1 2 2 2 1 3 2 2 1

The following figures give ALADIN results for all the weights calculated according to the 3

alternatives (3 experts).

Figure 4.3 shows the 3 sets of weights for people safety.

Figure 4.4 gives the weights for the contents.

Figure 4.5 presents the weights given on the protection of the building.

Expert Measure {LocDetect} {Sprinklers} {Water mist} {SmokeDetn} {Curtain} {Staff} 1 contents 7 7 0 5 0 5 persons 7 7 0 3 0 3 building 7 7 0 5 0 0 2 contents 7 0 7 1 7 3 persons 7 0 7 5 7 5 building 7 0 7 3 7 3 3 contents 7 0 7 1 0 3 persons 5 0 3 3 0 5 building 3 3 3 7 0 3


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Figure 4.6 shows the weights of the objectives on the general policy of safety/protection of

the cultural heritage.

Figure 4.7 shows the weights of the measures on the general policy of safety/protection of

the cultural heritage.

Table 4.6 gives the numerical values of the measures on the general policy of

safety/protection of the cultural heritage. The three columns represent the values associated

to the choices of the three experts. The “criteria” are given on the rows. Table 4.6

summarises the weights of the 3 alternatives on the policy. We can see that some values are

very close (e.g. 0.34 and 0.31, or 0.25 and 0.26, or 0.12 and 0.14). For these situations, the

influences have to be considered as equivalent. In other cases, e.g. for “sprinklers” or “water

mist”, the values are very different, because one measure was excluding the other one.

The cost has been roughly estimated for each alternative; C2 > C3 > C1. The person in

charge of the decision can then exploit this matrix that brings a synthesis of the decisions

elements. The question of optimisation of effectiveness/cost is addressed in the chapter 6.

0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4

{LocDetect} on {People}

{Sprinklers} on {People}

{Water mist} on {People}

{SmokeDetn} on {People}

{Curtain} on {People}

{Staff} on {People}Expert 3Expert 2Expert 1

Figure 4.3: Weights of measures on the Objective “safety of people”.


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0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4 0,45

{LocDetect} on {Contents}

{Sprinklers} on {Contents}

{Water mist} on {Contents}

{SmokeDetn} on {Contents}

{Curtain} on {Contents}

{Staff} on {Contents} Expert 3Expert 2Expert 1

Figure 4.4: Weights of measures on the Objective “protection of content”.

0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4

{LocDetect} on {Building}

{Sprinklers} on {Building}

{Water mist} on {Building}

{SmokeDetn} on {Building}

{Curtain} on {Building}

{Staff} on {Building} Expert 3Expert 2Expert 1

Figure 4.5: Weights of measures on the Objective “protection of the building”.


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0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4 0,45

{Contents} on {FS inMuseum}

{People} on {FS in Museum}

{Building} on {FS inMuseum}

Expert 3Expert 2Expert 1

Figure 4.6: Weights of Objectives on the Policy safety/protection of the Cultural Heritage.

0 0,05 0,1 0,15 0,2 0,25 0,3 0,35 0,4

{LocDetect} on {FS inMuseum}

{Sprinklers} on {FS inMuseum}

{Water mist} on {FS inMuseum}

{SmokeDetn} on {FS inMuseum}

{Curtain} on {FS in Museum}

{Staff} on {FS in Museum} Expert 3Expert 2Expert 1

Figure 4.7: Weights of measures on the Policy safety/protection of the Cultural Heritage.


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Table 4.6: the decision matrix

276367196COST (k€)0,220,140,12{Staff} on {FS in Museum}

0,170,100,21{SmokeDetn} on {FS in Museum}

0,000,250,00{Curtain} on {FS in Museum}

0,260,250,00{Water mist} on {FS in Museum}

0,030,000,34{Sprinklers} on {FS in Museum}

0,310,250,34{LocDetect} on {FS in Museum}

A3A2A1

276367196COST (k€)0,220,140,12{Staff} on {FS in Museum}

0,170,100,21{SmokeDetn} on {FS in Museum}

0,000,250,00{Curtain} on {FS in Museum}

0,260,250,00{Water mist} on {FS in Museum}

0,030,000,34{Sprinklers} on {FS in Museum}

0,310,250,34{LocDetect} on {FS in Museum}

A3A2A1

Acceptability and reliability of the measures

Up to now, these aspects had not been considered. We must mention they could have been

considered in weighting the measures. In this case study, we assume that the characteristics

considered for the measures were only efficiency. Then we can now consider new

characteristics in order to grade the alternatives. Another characteristic that can have a

strong influence on the conclusions of a study is the architectural acceptability. The following

table shows the results obtained after taking into account acceptability and reliability, and

cost (very approximate here), as presented in the report of WG4.


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Table 4.7 . New matrix with acceptability, reliability and cost.

Conclusion

The “best” alternative is finally alternative 2 because its cost is less than the maximum of 300

k€ and because the associated measures have a high level of reliability and acceptability.


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5. The IST COST/EFFECTIVENESS spreadsheet

Index hierarchy methods

Several hierarchy methods are calculating an index on the same basic concept of linear

dependency as the hierarchy methods presented above.

Following John M. Watts, JR. in « Fire Protection Performance Evaluation for Historic

Buildings » (Journal of FIRE PROTECTION ENGINEERING, Vol. 11, Nov. 2001):

“Indexing is a form of multi-attribute decision analysis that produces an accumulated score

of positive and negative system attributes contributing to the overall objective of an area of

concern. For example, the wind-chill factor accounts for both wind speed and temperature

to describe how cold it feels. In risk analysis, multi-attribute evaluation is usually referred to

as risk indexing. Fire risk indexing has been used for existing buildings for the last three

decades and has recently been applied to a class of historic buildings.”

The effectiveness index is calculated with the following expression:

Where G (k) is the grade of each measure M(k), M are the measures, ST the strategies, OB

the objectives and PO the policy.

IF the G (k) values are < 1, E is < 1. This the case for the two index methods presented

below. In ALADIN, we assume that the grading of a measure is included in the value given to

the measure before running ALADIN. Then E=1 in ALADIN that considers that the policy is

fully satisfied by the choice made and for which comparisons of alternatives are realised on

the outputs obtained after ALADIN’s runs.

This report describes:

♦ The index method reported in WG6 as a method of risk analysis ("Cultural heritage fire

risk index", report by Fredrik Nystedt, September 2003) but may as well be considered an

evaluation tool for DM. ANNEX 1 presents this method, which has the same basis as the

following spreadsheet.

( ) ( ) ( ) ( ) ( )∑∑ ∑= = =

⋅⋅⋅=6

1

5

1

19

1i j kkGkjMjiSTiOBPOE


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♦ The IST Cost/Effectiveness Spreadsheet developed in WG7 and applied in WG8 case

studies. The following lines come from IST (The Excel sheet “Cost_Effectiveness.xls”,I.

Cabrita Neves, Joaquim Valente, João Ventura, September 2004). The corresponding

spreadsheets are given in a separate Excel file.

Even if chapter 6 is addressing the question of optimisation of efficiency vs. cost, the way

the IST tool optimises the cost/efficiency ratio is presented here. In chapter 6 an example of

Cost/Effectiveness optimisation using this Excel sheet will be presented (from WG8 TNO

Case Study). Other WG8 Case Studies are also using this tool (see WG8 report).

5.1 Introduction

When studying the improvement of the fire safety conditions in a historic building several

alternatives will normally be considered. These alternatives need to be compared in terms of

the effectiveness of the whole set of fire safety measures in relation to the pre-defined Policy

or in relation to each pre-defined Objective. Different fire safety alternatives have different

costs. The relation between the improvement in effectiveness achieved by each alternative

and the corresponding cost (effectiveness improvement per Euro) is a crucial parameter for

the final decision.

The Excel sheet “Cost_Effectiveness.xls” was developed as a practical tool to perform that

task. A hierarchical approach is used to compare different fire safety alternatives.

5.2 Input

For a given study case, the following should be defined at first:

• Policy

• Objectives

• Strategies

• Fire safety measures

5.2.1 Policy

In general, the policy will be “to reduce the fire risk”.


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5.2.2 Objectives

The interested party in the study should be clearly identified prior to defining the objectives,

because these depend on who promotes the study.

The following 6 objectives are pre-defined in the spreadsheet:

• OB1 - Protect the occupants

• OB2 - Protect the firemen

• OB3 - Protect the building

• OB4 – Protect the contents

• OB5 - Safeguard continuity of activity

• OB6 - Protect the environment

If necessary, these objectives can be adapted or complemented by additional ones. It is

advisable to write a short description of what is understood by each of the objectives in

relation to each study case. This will help when setting the weights of each objective in

relation to the policy.

5.2.3 Strategies

The following 5 strategies are pre-defined in the spreadsheet:

• ST1 - Reduce the probability of fire start

• ST2 - Limit fire development/ propagation

• ST3 - Facilitate egress

• ST4 - Facilitate fire fighting and rescue operations

• ST5 - Limit the effects of fire products

It is advisable to write a short description of what is understood by each of the strategies and

to have these definitions always in mind when setting the weights of each strategy in relation

to each objective. The following definitions may be used as starting point and be improved,

if necessary.


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ST1 - Reduce the probability of fire start

This strategy will include every measure that may difficult the beginning of a fire.

ST2 - Limit fire development/ propagation

This strategy will include every measure that may delay the development or limit the extent of

a fire inside the compartment of fire start and also those that may prevent the fire

propagation to other compartments in the same floor, to other floors and to other buildings.

ST3 - Facilitate egress

This strategy will include every measure that may contribute to the quick and safe movement

of the occupants towards a safe place, normally outside the building.

ST4 - Facilitate fire fighting and rescue operations

This strategy will include every measure that may facilitate fire fighting at an early stage by

the occupants, by the staff or by an existing on site fire brigade and also, at a second stage,

the fire fighting and rescue operations by the firemen.

ST5 - Limit the effects of fire products

This strategy will include every measure that may limit the effects of smoke on people,

building and contents, and the effects of contaminated water on the environment.

5.2.4 Fire safety measures

The following 19 classes of fire safety measures are pre-defined in the spreadsheet:

• M1 - Reaction to fire

• M2 - Fire resistance of the structure

• M3 - Fire resistance of partitions

• M4 - Size of fire compartments

• M5 - Characteristics and location of the openings on the facades

• M6 - Distance between buildings

• M7 - Geometry of egress paths

• M8 - Access for the firemen


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• M9 - Means for fire detection

• M10 - Means for fire suppression

• M11 - Smoke control

• M12 - Emergency and alarm signs

• M13 - On site firemen

• M14 - Fire brigade

• M15 - Maintenance of fire safety systems

• M16 - Education for fire safety

• M17 - Emergency planning + training

• M18 - Salvage operation management

• M19 - Periodic inspection of the building

The measures should be adapted to each. It is advisable to write a short description of what

is understood by each class of fire safety measures and to have these descriptions always in

mind when setting the weights of each class of fire safety measures in relation to each

strategy. The following descriptions may be used as starting point and be improved/ adapted,

if necessary.

M1 - Reaction to fire

This class of fire safety measures refers to the control of the reaction to fire characteristics of

the construction materials used in the building, including structural materials, coating

materials and finishing materials, applied on interior as well as on exterior surfaces.

M2 - Fire resistance of the structure

This class of fire safety measures refers to the fire resistance of the load bearing elements.


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M3 - Fire resistance of partitions

This class of fire safety measures refers to the fire resistance of all those elements from

which it is expected an adequate performance on preventing the fire spread between distinct

fire compartments. It includes the integrity and the insulation criteria, and also, if adequate,

the load bearing criterion.

M4 - Size of fire compartments

This class of fire safety measures aims at limiting the consequences of a fire and at

facilitating the fire fighting operations. In new buildings, different floors are usually distinct fire

compartments. This is often not so in old buildings, where the whole building builds up

sometimes one single fire compartment. Correcting this in historic buildings is frequently

difficult. Compensation by other fire safety measures is then the solution. Nevertheless, in

some cases, it may be possible to improve the fire resistance of existing elements in order to

reduce the size of fire compartments.

M5 - Characteristics and location of the openings on the facades

This class of fire safety measures aims at limiting the fire spread between storeys. It includes

the distance between windows in the same vertical, the fire resistance of the window pane,

and the possible existence of balconies.

M6 - Distance between buildings

This class of fire safety measures is intended to limit the fire propagation between facing

buildings. In old urban areas this is frequently a critical factor.

M7 - Geometry of egress paths

This class of fire safety measures is intended to facilitate the quick egress of the building. It

includes the width of corridors and stairs, the length of a path from any point within the

building to a protected egress path and the number and distribution of alternative egress

paths.

M8 - Access for the firemen

This class of fire safety measures is intended to facilitate the fire fighting and rescue

operations by the firemen. It refers to the geometry of the streets leading to the entrances

and to the penetration points of the building and the eventual existence of obstacles to the

fire brigade operation.


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M9 - Means for fire detection

This class of fire safety measures has the purpose of detecting the fire as early as possible in

order to alarm the occupants, transmit the alert to the fire brigade and begin the fire fighting

operations. Examples are: detection by the occupants during day time; detection by a

watchman during the night; automatic smoke detection; automatic heat detection; automatic

flame detection; CCTV system connected to a security room (this may also be a means of

detecting suspicious behaviour of potential arsonists).

Automatic intrusion detection may also be included in this class, in the sense that intrusion

can lead to arson.

M10 - Means for fire suppression

This class of fire safety measures has the purpose of extinguishing the fire within the shortest

period of time. Examples: hose reels; automatic water sprinkler systems; portable

extinguishers; water mist systems; gaseous suppression systems.

M11 - Smoke control

This class of fire safety measures has the purpose of keeping the egress paths free from

smoke, and of limiting the effects of smoke on people, contents and building. It also aims at

facilitating the action of firemen.

M12 - Emergency and alarm signs

This class of fire safety measures has the purpose of warning the occupants about an

existing fire, to give them indications about the evacuation process and to guarantee enough

visibility during the evacuation. It includes such components as emergency lighting, voice

alarm systems, and bell and siren systems.

M13 - On site firemen

This class of fire safety measures has the purpose of initiating the fire fighting as early as

possible. On site fire brigades possess a good knowledge of the building, receive training

and are on site, which increases their effectiveness.

M14 - Fire brigade

This class of fire safety measures has the purpose of fighting the fire once it has been

detected and the alert transmitted. The time the fire brigade needs to arrive and their

equipment are important factors to consider.


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M15 - Maintenance of fire safety systems

This class of fire safety measures aims at reducing the probability of failure of the fire safety

systems. Inspection and testing of the fire safety systems should be done on a regular basis.

M16 - Education for fire safety

This class of fire safety measures is intended to increase the level of knowledge of the

occupants about the fire phenomena, making them aware of the correct behaviour in order to

prevent fire initiation and to limit their consequences.

M17 - Emergency planning + training

This class of fire safety measures is intended to anticipate every possible risk, to establish

the right procedure for every situation and to test these procedures.

M18 - Salvage operation management

This class of fire safety measures consists in defining and testing in advance the set of

adequate procedures to minimize the damage to the contents of the building. Examples are:

identification, ranking and labelling of the most valuable items; transport of valuable items to

a previously identified safe place; definition of the adequate storing conditions for each item.

M19 - Periodic inspection of the building

This class of fire safety measures aims at identifying possible sources of fire start. Examples

of fire safety measures from this class are: identification of malfunctioning devices;

identification of undue storage of objects in the egress paths; identification of unnecessary

accumulation of easily combustible materials.

For examples of general fire safety measures and of those which are more suitable for the

protection of Cultural Heritage, reference is made to the FiRE-TECH WG4 Report.


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5.3 Scores and weights

The second and very important task will be the definition of the weights (importance) of the

parameters in each level on the parameters in the level above. This can be more

conveniently achieved by attributing scores to each parameter representing their importance

in relation to each of the parameters in the level above. A scale like the one shown in table

5.1 could be used. The spreadsheet then automatically transforms these scores into

normalized weights.

Preference / importance Scores

None 0

Very little 1

Weak 3

Medium 5

Strong 7

Absolute 9

Table 5.1 - Scale for setting the scores

(See also A2.2)

The scores to be defined are:

• OB(i) - representing the importance of each objective i on the policy

• ST(ji) - representing the importance of each strategy j on each objective i

• M(kj) - representing the importance of each fire safety measure class k on each strategy j


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a) Importance of each objective i on the policy, OB(i)

Even if we keep in mind that our main concern within the scope of the FiRE-TECH project is

the protection of Cultural Heritage, an integrated approach to fire protection cannot disregard

objectives like the protection of occupants and the protection of firemen. The definition of the

scores representing the importance of each objective on the pre-defined policy is clearly a

political task, and the values depend on the study case and on whom is the party interested

in the study.

The spreadsheet transforms these scores into normalized weights OB (i) such that

( ) 16

1=∑

=iiOB (1)

OB1 - Protect the occupants

OB2 - Protect

the firemen

OB3 - Protect

the building

OB4 - Protect

contents

OB5 - Safeguard

continuity of activity

OB6 - Protect the

environment PO -

Reduce fire risk

Scores OB(i)

Normalized OB(i)

Table 5.2 – Table of scores and normalized weights OB(i)


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b) Importance of each strategy j on each objective i, ST(ji)

The choice of these scores has to be based on technical knowledge and may depend on the

study case.

ST1 -

Reduce the

probability of

fire start

ST2 - Limit fire

development/

propagation

ST3 -

Facilitate

egress

ST4 -

Facilitate

fire fighting

and rescue

ST5 - Limit

the effects

of fire

products

ST(j1) OB1 - Protect

the occupants Normalized

ST(j1)


the firemen Normalized

ST(j2)


the building Normalized

ST(j3)


contents Normalized

ST(j4)

ST(j5) OB5 -

Safeguard

continuity of

activity

Normalized

ST(j5)


the environment Normalized

ST(j6)

Table 5.3 - Table of scores and normalized weights ST (ji)

The spreadsheet normalizes these scores, giving rise to weights ST(ji) such that

( ) ( )6,115

1==∑

=

ijiSTj

(2)


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c) Importance of each fire safety measure class k on each strategy j, M(kj)

The choice of these scores has to be based on technical knowledge and may depend on the

study case.

The spreadsheet normalizes these scores, giving rise to weights M(kj) such that

( ) ( )5,1119

1==∑

=

jkjMk

(3)

The breaking of Table 5.4 (as well as Tables 5 and 6) is only due to formatting reasons.


M2 - Fire resistance of

structure


partitions


M(k1) ST1 - Reduce the

probability of fire start Normalized

M(k1)

M(k2) ST2 - Limit fire

development/ propagation Normalized

M(k2)

M(k3) ST3 - Facilitate

egress Normalized M(k3)

M(k4) ST4 - Facilitate

fire fighting and rescue Normalized

M(k4)

M(k5) ST5 - Limit the

effects of fire products Normalized

M(k5)

Table 5.4 a) - Table of scores and normalized weights M(kj)


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M5 - Characteristics and location of

openings on the facades




M9 - Means for fire

detection


probability of fire start Normalized M(k1)


development/ propagation Normalized M(k2)

M(k3)

ST3 - Facilitate egress Normalized M(k3)

M(k4) ST4 - Facilitate fire

fighting and rescue Normalized M(k4)

M(k5) ST5 - Limit the effects

of fire products Normalized M(k5)

Table 5.4 b) - Table of scores and normalized weights M(kj)

M10 - Means for fire

suppression

M11 - Smoke control

M12 - Emergency and

alarm signs


M14 - Fire brigade





M(k3)






Table 5.4 c) - Table of scores and normalized weights M(kj)


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M15 - Maintenance of

fire safety systems

M16 - Education

for fire safety

M17 - Emergency planning +

training

M18 - Salvage

operation management

M19 - Periodic inspection of the building





M(k3)






Table 5.4 d) - Table of scores and normalized weights M(kj)

5.4 Grades of implementation of the fire safety measures

In a given study case, the existing situation will be characterized by the fact that each class of fire safety measures is already implemented to a certain degree. This implementation grade ranges from zero, when the class of fire safety measures is totally absent, to the value of one, when the class is fully and satisfactorily implemented.

In old buildings, the task of choosing some of these implementation grades is more difficult as a consequence of the difficulty in making a proper characterization of relevant properties, such as the reaction to fire of ancient materials, or the fire resistance of building components and assemblies, for instance. Nevertheless, having components with an assumed unsatisfactory fire performance is not the same as not having them at all. This has to be translated into an implementation grade, no matter how difficult it may appear. Expert judgement is very useful and the Delphi method might be a way to achieve this purpose.

Sometimes, due to the constraints in historic buildings it may be only possible to upgrade some of the components of a given system. If this is the case, an evaluation of the effect of that improvement on the resulting implementation grade has to be made on a technical basis.


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It is often necessary to weigh the global influence of a set of components of a given fire safety system, rather than weighing each individual component separately. The final grade is naturally influenced by the assumed contribution of each component. This is particularly true when evaluating the situation in old buildings where the fire safety conditions are unsatisfactory. Nevertheless, the partial contribution of each component has to be evaluated and taken into account. The fire safety level is the result of the summation of these partial contributions.

There are often classes of fire safety measures that cannot be applied or improved. Others give only small improvements. But the joint contribution of several of them can result in a lower fire risk.

The choice of the implementation grades should be adapted to each study case and be based on the existing knowledge about the suitability, performance and reliability of the various components that play a role on a given fire safety measure class. In this task, the report of FiRE-TECH Working Group 4 may be a useful tool.

The spreadsheet is prepared to receive implementation grades for an initial situation and for two additional fire safety alternatives.

Fire safety measures M1 -

Reaction to fire


structure


partitions




Grade of implementation G(k)

Initial situation Grade of

implementation G(k) Alternative 1


Alternative 2

Table 5.5 a) - Table of implementation grades G(k)

Fire safety measures M6 - Distance

between buildings



M9 - Means for fire

detection






Alternative 2

Table 5.5 b) - Table of implementation grades G(k)


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Smoke control

M12 - Emergency and

alarm signs


M14 - Fire brigade






Alternative 2

Table 5.5 c) - Table of implementation grades G(k)

Fire safety measures



training

M18 - Salvage operation

management

M19 - Periodic inspection of the

building

Grade of implementation

G(k) Initial situation


G(k) Alternative 1


G(k) Alternative 2

Table 5.5 d) - Table of implementation grades G(k)

5.5 Costs associated to the implementation of each class of fire safety measures.

Once defined the fire safety measures to be implemented in each fire safety alternative, the

corresponding associated costs have to be evaluated and put in the spreadsheet.

Fire safety measures M1 - Reaction to fire


structure


partitions




Costs Ck of implementing alternative 1 Costs Ck of

implementing alternative 2

Table 5.6 a) – Costs of implementing alternatives 1 and 2


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Fire safety measures M6 - Distance

between buildings







Table 5.6 b) – Costs of implementing alternatives 1 and 2


Smoke control

M12 - Emergency and

alarm signs

M13 - On site firemen M14 - Fire brigade

M15 - Maintenance of

fire safety systems



Table 5.6 c) – Costs of implementing alternatives 1 and 2

Fire safety measures M16 - Education for fire safety


training

M18 - Salvage operation management


building



Table 5.6 d) – Costs of implementing alternatives 1 and 2

5.6 Output

For a global view, the output sheet shows the input grades of implementation of each class

of fire safety measures for the initial situation and for the two additional fire safety

alternatives, and the corresponding costs.


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The output sheet also contains the following results:

1) the influence of each measure on the policy and on each objective, assuming the full implementation of all measures (implementation grades equal to one)

Influence of each measure on

MEASURES PO

Reduce fire risk

OB1 Protect

the occupants

OB2 - Protect the

firemen

OB3 - Protect

the building

OB4 - Protect

contents

OB5 - Safeguard


OB6 - Protect the

environment



structure


partitions


M5 - Characteristics and

location of openings on the

facades






M11 - Smoke control



M14 - Fire brigade

M15 - Maintenance of fire safety

systems


M17 - Emergency planning + training


management


building

Table 5.7


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2) the weighted influence (effectiveness) of each measure on the policy and on each objective for the initial situation.

Initial situation – Weighed influence (effectiveness) of each measure on

MEASURES PO –

Reduce fire risk

OB1 – Protect

the occupan

ts

OB2 – Protect the

firemen

OB3 – Protect

the building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment

M1 – Reaction to fire

M2 – Fire resistance of

structure M3 – Fire

resistance of partitions

M4 – Size of fire compartments

M5 – Characteristics and

location of openings on the

facades M6 – Distance

between buildings M7 – Geometry of

egress paths M8 – Access for

the firemen M9 – Means for fire

detection

M10 – Means for fire suppression M11 – Smoke

control M12 – Emergency and alarm signs

M13 – On site firemen

M14 – Fire brigade

M15 – Maintenance of fire safety

systems M16 – Education

for fire safety M17 – Emergency planning + training

M18 – Salvage operation

management M19 – Periodic

inspection of the building

Table 5.8


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3) the weighted influence (effectiveness) of each measure on the policy and on each objective for the fire safety alternative 1

Alternative 1 - Weighed influence (effectiveness) of each measure on

MEASURES PO -

Reduce fire risk

OB1 - Protect the

occupants

OB2 - Protect the

firemen

OB3 - Protect

the building

OB4 - Protect

contents

OB5 - Safeguard


OB6 - Protect the

environment


M2 - Fire resistance of structure










M11 - Smoke control



M14 - Fire brigade


M16 - Education for

fire safety M17 - Emergency planning + training




Table 5.9


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4) the weighted influence (effectiveness) of each measure on the policy and on each objective for the fire safety alternative 2

Alternative 2 - Weighed influence (effectiveness) of each measure on

MEASURES PO –

Reduce fire risk

OB1 – Protect

the occupants

OB2 – Protect the

firemen

OB3 – Protect

the building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment


M2 – Fire resistance of structure

M3 – Fire resistance of partitions


M5 – Characteristics and location of


M6 – Distance between buildings M7 – Geometry of

egress paths M8 – Access for the

firemen M9 – Means for fire

detection

M10 – Means for fire suppression

M11 – Smoke control

M12 – Emergency and alarm signs




systems M16 – Education for

fire safety M17 – Emergency planning + training




Table 5.10


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5) the improvement in effectiveness (%) due to the implementation of the fire safety alternative 1

Improvement in effectiveness (%) due to implementation of Alternative 1

MEASURES PO –

Reduce fire risk

OB1 – Protect

the occupants

OB2 – Protect the

firemen

OB3 – Protect

the building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment










detection












Table 5.11


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6) the improvement in effectiveness (%) due to the implementation of the fire safety alternative 2

Improvement in effectiveness (%) due to implementation of Alternative 2

MEASURES PO -

Reduce fire risk

OB1 - Protect

the occupants

OB2 - Protect the

firemen

OB3 - Protect

the building

OB4 - Protect

contents

OB5 - Safeguard


OB6 - Protect the

environment


M2 - Fire resistance of structure





M6 - Distance between buildings M7 - Geometry of

egress paths M8 - Access for the

firemen M9 - Means for fire

detection


M11 - Smoke control



M14 - Fire brigade

M15 - Maintenance of fire safety

systems M16 - Education for

fire safety M17 - Emergency planning + training


management M19 - Periodic


Table 5.12


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7) the increase in effectiveness (%) per kEuro due to the implementation of the fire safety alternative 1

Increase in Effectiveness (%) per kEuro – Alternative 1

MEASURES PO –

Reduce fire risk

OB1 – Protect

the occupants

OB2 – Protect the

firemen

OB3 – Protect

the building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment










detection












Table 5.13


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8) the increase in effectiveness (%) per kEuro due to the implementation of the fire safety alternative 2

Increase in Effectiveness (%) per kEuro – Alternative 2

MEASURES PO –

Reduce fire risk

OB1 – Protect

the occupants

OB2 – Protect the

firemen

OB3 – Protect

the building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment










detection












Table 5.14


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9) for the initial situation, for the fire safety alternative 1 and for the fire safety alternative

2, the influence of the implemented fire safety measures on the policy (Effectiveness

index E(PO)), and the influence of the implemented fire safety measures on each

objective (Effectiveness index E(OBi)), taking into account the relative contribution of

that objective to the policy.

( ) ( ) ( ) ( ) ( )∑∑∑= = =

⋅⋅⋅=6

1

5

1

19

1i j kkGkjMjiSTiOBPOE (4)

( ) ( ) ( ) ( )∑∑= =

⋅⋅⋅=5

1

19

1)(

j k

kGkjMjiSTiOBOBiE (5)

MEASURES PO –

Reduce fire risk

OB1 – Protect the occupants

OB2 – Protect the

firemen

OB3 – Protect the

building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment

E(PO), E(OBi)

Initial situation

E(PO), E(OBi)

Alternative 1

E(PO), E(OBi)

Alternative 2

Table 5.15

10) for the fire safety alternatives 1 and 2, the global ratio Effectiveness/ Cost in relation to

the policy (increase in effectiveness obtained by each fire safety alternative in relation

to the policy per kEuro spent)

1

19

1

01 )()(

−

∑=k

kC

POEPOE (6)

2

19

1

02 )()(

−

∑=k

kC

POEPOE (7)


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11) for the fire safety alternatives 1 and 2, the ratio Effectiveness/ Cost in relation to each

objective (increase in effectiveness obtained by each fire safety alternative in relation to

each objective per kEuro spent).

1

19

1

01 )()(

−

∑=k

k

ii

C

OBEOBE (8)

2

19

1

02 )()(

−

∑=k

k

ii

C

OBEOBE (9)

MEASURES PO –

Reduce fire risk

OB1 – Protect the occupants

OB2 – Protect the

firemen

OB3 – Protect the

building

OB4 – Protect

contents

OB5 – Safeguard


OB6 – Protect the

environment

Ratio Effectiveness/ Cost

Alternative 1

Ratio Effectiveness/ Cost

Alternative 2

Table 5.16 – Ratios Effectiveness/ Cost

For a better visualization of the results, a graphical representation of the output data can be

found in separate sheets.

The worksheets are write-protected without password, so that the user can always adapt

them to his personal needs.


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6. OPTIMISATION of COST /EFFECTIVENESS

6.1 ALADIN APPROACH

The example of CSTB WG8 case study (see § 4) will still be considered here.

We will here continue the assessment of the measures by an evaluation of the reliability of

the systems (from the data of the WG 4 report).

The following Table 6.1 presents the acceptability (already considered in the choice of the

measures), the reliability (considered now) and the cost (very approximate here), that must

be less than 300 k€.

Table 6.1


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The following Table 6.2 presents the weights of the alternatives on the safety/protection of the virtual museum.

Alternative 1 Alternative 2 Alternative 3

{LocDetect} on {FS in Museum} 0,34 0,25 0,31

{Sprinklers} on {FS in Museum} 0,34 0,00 0,03

{Water mist} on {FS in Museum} 0,00 0,25 0,26

{SmokeDetn} on {FS in Museum} 0,21 0,10 0,17

{Curtain} on {FS in Museum} 0,00 0,25 0,00

{Staff} on {FS in Museum} 0,12 0,14 0,22

1,00 1,00 1,00

Table 6.2

Table 6.3 presents the new weight after reliability has been considered. The global reliability is: 0.89, 0.86, 0.82, and does thus not vary much. The cost has to be lower than 300 k€. Then alternative 2 is not acceptable. Alternative 1 is much cheaper than alternative 3, with a slightly higher reliability. It has then to be chosen.

Reliability Alternative 1 Alternative 2 Alternative 3

{LocDetect} on {FS in Museum} 1,00 0,34 0,25 0,31

{Sprinklers} on {FS in Museum} 0,80 0,27 0,00 0,03

{Water mist} on {FS in Museum} 0,60 0,00 0,15 0,16

{SmokeDetn} on {FS in Museum} 0,90 0,19 0,09 0,15

{Curtain} on {FS in Museum} 1,00 0,00 0,25 0,00

{Staff} on {FS in Museum} 0,80 0,10 0,11 0,18

0,89 0,86 0,82 [Costmax - Cost (i)] / Costmax 0,54 0,00 0,25 Cost(i) 169,15 366,65 276,15

Costmax 366,65 366,65 366,65

Table 6.3

This example shows how: - the cost,

- a further (after ALADIN) assessment of the alternative (here reliability), can permit to choose the best ratio efficiency/cost.

More complex tools can also be used to compare alternatives, based on over-ranking methods (Bernard Roy et al., cf. ANNEX 1).


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6.2 Application made by TNO using the first version of the IST COST/EFFECTIVENESS spreadsheet

(The latest version of the IST spreadsheet incorporates Effectiveness / Cost ratios and graphs, as a consequence of the applicaton made by TNO)

Different measures can be taken to obtain a fire safe situation in the Nieuwe Kerk. As was shown in the WG8 report by TNO (par. 6.4), these measures can be ranked in order of importance for the overall fire safety. Using the modified IST excel sheet, the importance of each measure is given in Figure 6.4

Weights of the measures on PO (Reduce fire risk)

0.000 0.010 0.020 0.030 0.040 0.050 0.060 0.070 0.080 0.090 0.100

P1 - Sprinklers

P2 - First aid fire fighting equipment

P3 - Automatic fire detection

P4 - Alaram systems

P5 -Visual signals and evacuation plans

P6 - Smoke control

P7 - Fire resistance of glazing

P8 - Inert insulating materials

P9 - Intumescent materials

P10 - CCTV

P11 - Training of personnel

P12 - Procedures for evacuation of people

P13 - Fire guards during large events

P14 - Guides accompanying vistors to tower

P15 - Control of installations

P16 - Guidelines during renovation

P17 - Burglary alarm

P18 - Limit unnecessary flammable items

P19 -Contact with fire services

Weights

full level of implementation

Figure 6.4 effectiveness of each measure if fully implemented

In the current situation only some measures have been (partially) implemented. Each measure gives a certain contribution to the overall effectiveness index (EI) with its current grade of implementation. The current contributions to the overall EI are compared to the maximum values in figure 6.5. The green values again represent full implementation of a measure, the red value the current level of implementation (G).


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0.000 0.010 0.020 0.030 0.040 0.050 0.060 0.070 0.080 0.090 0.100

P1 - Sprinklers



P4 - Alaram systems


P6 - Smoke control




P10 - CCTV










Weights

current level of implementationfull level of implementation

Figure 6.5: Contributions of all measures to EI, for current situation and situation with full implementation of all measures

However, to increase the grade of implementation of a certain measure does not necessarily lead to G=1 for that measure; possibly a measure can relatively easily be improved to e.g. G=0.9, while obtaining G=1.0 would require large investments. Therefore, for each measure an estimation has been made of a feasible grade of implementation. (This estimate only serves as an example, and has not been verified!) In figure 6.6 this proposed new grade of implementation is shown in yellow and compared to current and full grades of implementation.


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0.000 0.010 0.020 0.030 0.040 0.050 0.060 0.070 0.080 0.090 0.100

P1 - Sprinklers



P4 - Alaram systems


P6 - Smoke control




P10 - CCTV










Weights

current level of implementationproposed new level of implementationfull level of implementation

Figure 6.6 current, proposed new and maximum grades of implementation of all measures


0.000 0.010 0.020 0.030 0.040 0.050 0.060

P1 - Sprinklers



P4 - Alarm systems


P6 - Smoke control




P10 - CCTV










Weights

possible increase of EI if measureis implemented as proposed

Figure 6.7: possible increase in EI due to full or partial implementation of each measure


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Assume that there is a certain (given) budget available to improve the fire safety of the Nieuwe Kerk. Objective is to increase the effectiveness index as much as possible with this money.

All costs have to be indexed to net market values for the time of investment. For each measure it is estimated what the costs of an improvement would be, and what the new grade of implementation (G) would be after the improvement. The estimated costs are given in Table 6.3. (This estimate only serves as an example, and has not been verified!)

Table 6.3: estimated costs of improvements

measure Current grade of

implementation

Proposed new grade of

implementation

cost of improvement

[k€]

P1 - Sprinklers 0.8 1.0 150

P2 - First aid fire fighting equipment 0.7 1.0 25

P3 - Automatic fire detection 0.5 0.7 25

P4 - Alaram systems 0.8 1.0 25

P5 -Visual signals and evacuation plans 0.1 0.8 50

P6 - Smoke control 0.8 0.8 -

P7 - Fire resistance of glazing 0.7 0.7 -

P8 - Inert insulating materials 0.3 0.6 75

P9 - Intumescent materials 0.4 0.5 25

P10 - CCTV 0.5 1.0 100

P11 - Training of personnel 0.9 0.9 -

P12 - Procedures for evacuation of people 1.0 1.0 -

P13 - Fire guards during large events 0.0 1.0 50


0.2 1.0 200

P15 - Control of installations 0.3 1.0 50

P16 - Guidelines during renovation 1.0 1.0 -

P17 - Burglary alarm 0.8 0.8 -

P18 - Limit unnecessary flammable items 1.0 1.0 -

P19 -Contact with fire services 1.0 1.0 -

The model calculates the effect that the increase of G has on the total EI; therefore it is possible to relate the costs of each measure to the obtained overall effectiveness index.


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This gives a ranking as follows, see also figure 6.8:

- P13 - Fire guards during large events 0.11 %/k€ (this means that if money is invested in P13, for each 1000 € the EI will increase 0.0011).

- P15 - Control of installations 0.089 %/k€ - P2 - First aid fire fighting equipment 0.062 %/k€ - P3 - Automatic fire detection - P5 -Visual signals and evacuation plans - P4 - Alarm systems - P14 - Guides accompanying visitors to tower - P8 - Inert insulating materials - P9 - Intumescent materials - P10 - CCTV - P1 - Sprinklers

The other measures are either already fully implemented or impossible to improve.

Costs effectiveness per measure (improvement of EI per invested kEuro)[%/kEuro]

0.0000 0.0200 0.0400 0.0600 0.0800 0.1000 0.1200

P1 - Sprinklers



P4 - Alaram systems


P6 - Smoke control




P10 - CCTV










Cost effectiveness [%EI / kEuro]

Figure 6.8: cost effectiveness of each measure

Figure 6.8 can be compared to figure 6.7. This shows that the cost effectiveness calculation changes the ranking of measures, compared to a ranking purely on possible improvement per measure.

If the available money is invested according to the above ranking, the increase of the effectiveness index is always maximum that can be achieved for a certain budget. In figure 6.9 is shown, which EI can be achieved if the budget is invested according to the ranking.


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0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

0 100 200 300 400 500 600 700 800

costs (kEUR)

Effe

ctiven

ess Inde

x

none

P13

P13 + P15P13 + P15 + P2

P13 + P15 + P2 + P3

P13 + P15 + P2 + P3 + P5

… + P4 … + P14

… + P8… + P9 … + P10

… + P1

Figure 6.9 optimum EI dependent in available budget

E.g. if a budget of 200.000 € is available, the most cost-effective option is to install the measures P13 - Fire guards during large events, P15 - Control of installations, P2 -First aid fire fighting equipment, P3 - Automatic fire detection and P5 -Visual signals and evacuation plans. The EI will then be increased from 0.666 to 0.805.

It is interesting to see what benefits can be gained from this method. If it is assumed that costs are not taken into account, then the priorities for investing in fire safety measures would probably be based on the possible increase of the overall EI due to each measure. This means that the order of investing is according to figure 6.7 instead of figure 6.8. In that case, the relation between invested budget and obtained EI would be as shown in figure 6.10.

A close comparison of figures 6.9 and 6.10 shows that there are substantial benefits to be gained by a cost effectiveness assessment. If the aim is an EI of 0.8 the required investment can be lowered from 300 k€ to 200 k€. If the aim is an EI of 0.85 the amount goes down from 575 k€ to 425 k€.

0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

0 100 200 300 400 500 600 700 800

costs (kEUR)

Effe

ctiven

ess In

dex

Figure 6.10: EI dependent on available budget without cost effectiveness assessment


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7. Conclusions on Help to Decision-Making

Optimisation of fire safety and fire protection in Cultural Heritage implies the examination of possible alternative technical and organisational actions and, of course, an evaluation of associated costs, in order to retain acceptable solutions. The method of Help to Decision-Making used must be able to produce a selection of the best alternative(s) or a ranking of all the alternatives.

WG7 has developed and applied an approach presenting the following characteristics:

• "Help to Decision-Making" can address any aspect of safety or protection the expert is thinking of.

• The decision problem is decomposed in several “possible actions” at different depths of analysis, from global goals to precise actions.

• The method gives a general network view of inputs and outputs. It quantifies the effectiveness of assessments and expert’s opinion. It assigns weights (importance of influence) to different possibilities relative to one another.

• Identification of the most promising alternatives can be done solving a mathematical programming problem.

• The developed tools are simple to use and not time consuming.

The DM approach retained in FIRE-TECH is based on the “Hierarchy Analysis” that uses a decomposition of the main goal in “sub goals” at several levels “below“ the general goal top level. At each level of the “generality scale”, a judgement is made on the relative efficiency of each component of this level on each component of the levels above; several “boxes” corresponding to possible actions are weighted. From very general to less general (policy, objectives, strategies and measures), the weights given express the influence of a row on the actions of each box of the upper row. We assume that the influences are linear. Then matrix or linear combination formulae are used to calculate the dependency between boxes. The outputs are the relative influence of all the components are calculated so that the best solutions (the best alternatives) can be identified and weighted or a ranking be established.

The DM approach is one step in the global study of a Cultural Heritage and is strongly connected to others tasks. This step is located in phase 4, if:

• Phase 1 is the preliminary phase (qualitative definition of final goal awaited, evaluation of time and money available …),

• Phase 2 correspond to the analyse of the present level of safety and protection of the cultural heritage (Prescriptive and expert analysis, Performance based Quantitative Risk Analysis),


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• Phase 3 is the collection of possible actions to improve safety and protection (technical actions, non-technical actions…). Phase 3 gives the alternatives to be assessed and compared.

The following two-DM tools have been developed and applied to several cases (Cf. the WG8 report). The applications made have permitted to test the tools and to develop ways to take cost into account as well as the effectiveness aspects of the alternatives.

ALADIN

ALADIN is a FORTRAN programme based on the basic principles of Hierarchy Analysis. It leads to a ranking of alternatives. The use is very simple because the programme is asking simple questions about the network to build and the values to give. The results are the calculated influences. ALADIN can be used to calculate e.g. the combined weights on policy and objectives of given strategies and measures, as well as to compare the combined weights of several alternatives (established by one hesitating person or by a group of several experts).

ALADIN follows the decomposition of levels presented on: “policy, objectives, strategies, measures”. ALADIN was not conceived to deal with many measures and/or many strategies, as the maximum number of boxes in a row is 6 and the numbers of rows is limited to five.

ALADIN can address e.g. the following situations:

• Discussion and negotiation between experts have already limited the set of possible alternatives. The final choice to be made concerns then a few “boxes”.

• “Zooming” on partial influences, e.g. in using it on a small network, e.g.: one given objective, some strategies, and a few measures.

• A decision matrix is wished. The results will be presented under the format of such a matrix. Table 4.5 gives an example of a decision matrix with 3 alternatives in columns. The criteria (e.g. objectives or measures) are in rows. Additional rows can be added to consider new “criteria” such as cost (in order to consider cost/effectiveness), or reliability (if these criteria have not been considered already in the previous weighting). This matrix can be exploited directly or with the help of overranking methods.

The IST COST/EFFECTIVENESS spreadsheet

Several hierarchy methods are calculating an index on the same basic concepts of linear dependency as in ALADIN. Several specific features of the IST Cost/Effectiveness spreadsheet have to be mentioned:


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• In the IST spreadsheet a global risk index is calculated for each alternative considered because each measure is given a grade of implementation. Another index method is presented in Annex 3.

• The IST tool is based on EXCEL. Many actions are proposed at different levels. Each action not retained receives a weight zero. Retained actions are given relative weights. The utilisation is very simple and histograms give a graphic view of the results.

• The initial state (before any improvement of the protection and safety to the Cultural Heritage) is evaluated and two alternatives can be evaluated simultaneously and then compared to the initial state and compared to each other.

• The relation between the improvement in effectiveness achieved by each alternative and the corresponding cost (effectiveness improvement per Euro) is taken into account. The spreadsheet calculates the cost of each combination of actions and authorises the user to choose the best ratio effectiveness/cost for 2 alternatives or to look for a new alternative leading to a better ratio.

Final comments

The concepts developed here for fire protection and fire safety could be applied to other questions concerning Cultural Heritage. We are nevertheless missing experience since the use of such methods and tools is still very recent. We hope that the two tools presented above will be useful for the success of practical actions and that the experience gained will bring fresh knowledge to enrich future approaches.


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8. REFERENCES

• Buchanan, John and Sheppard, Phil, Ranking Projects Using the ELECTRE Method, 23 June 1998.

• Bukowski, Richard W.; Nuzzolese, Vincenzo; Bindo, Mirella, « Performance-based Fire Protection of Historical Structures » 20 October 2003.

• FIRE-TECH - WG7 draft report, Presentation of the fire-tech method to help to decision-making in fire protection of cultural heritage, Michel Curtat, February 2004).

• Karlsson, Björn and Larsson, Daniel, “Using a Delphi panel for developing a Fire Risk Index Method for Multi-Storey Apartment Buildings”, Report Lund University, 2000.

• Krick, E.V., “An Introduction to Engineering and Engineering Design”, second edition, John Wiley & Sons, Inc., New York, 1969.

• Magnusson, Sven Erik and Rantatalo, Tomas, Lund University Internrapport 7004, 1998: "Risk Assessment of Timberframe Multi-storey Apartment Buildings. Proposal for a Comprehensive Fire Safety Evaluation Procedure"

• Roy, Bernard, Méthodologie Multicritère d’aide à la Décision, Ed. Economica, 1985.

• Saaty, Thomas Lorie, “The Analytic Hierarchy Process – Planning, Priority setting, Resource allocation”, 1980.

• Shields, J., and Silcock, G., “An Application of the Hierarchical Approach to Fire Safety”, Fire Safety Journal, n°11, 1986.

• Shields, J., Silcock, G. and Y. Bell, “Fire Safety Evaluation of Dwellings”, Fire Safety Journal, n°10, 1986.

• Watts John M., JR. “Fire Protection Performance Evaluation for Historic Buildings”, Journal of FIRE PROTECTION ENGINEERING, Vol. 11, Nov. 2001.

• Watts, John M., Jr., “Fire Risk Indexing,” Section 5, Chapter 10, SFPE Handbook of Fire Protection Engineering, National Fire Protection Association, 3rd ed., Quincy, MA, 2001

• Zhao, C.M., Loa, S.M., Lu, J.A. , and Fang, Z., “A simulation approach for ranking of fire safety attributes of existing buildings”, Fire Safety Journal 39 (2004) 557–579.


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ANNEX 1. Other DM approach: B. Roy et al. Several methods and tools (ELECTRE, PROMETHEE, GAIA, …) have been developed by

Bernard Roy et al. at the University of Paris and applied and enriched by a ” French school of

DM”. Matrices again are considered: alternatives are on the rows, criteria on the columns. A

basic concept is outranking. Outranking is less concerned with a method for applying

weights to attributes, and more with a holistic comparison of Alternative A to Alternative B.

Roy's utilizes both concordance and discordance measures for accomplishing this. The

concordance measure is a ratio computed by summing the weights for those attributes for

alternative A which are superior to the attributes for Alternative B divided by the weights for

Alternative A as a whole. The closer this ratio is to 1.0, the more superior Alternative A is to

Alternative B. The discordance measure looks the largest difference for the attribute sets of A

over B compared to the largest difference over all alternatives. Multiple Criteria Decision

Aiding with the invention of the family of ELECTRE methods and methodological

contributions to decision aiding that lead to the creation of DM teams.

PROMETHEE is an example of method produced. In the PROMETHEE method, the user

has not to perform a large number of comparisons, as he can directly use the data of the

problem in a simple multicriteria table. The decision-maker has to define his own scales of

measure (without limitation), to indicate his priorities and his preferences for every criterion.

PROMETHEE allows conducting easily and quickly analyses of sensibility. PROMETHEE

calculates too the robustness of the current classification for each criterion.

It is very difficult to compare the awaited advantages and drawbacks of the two methods

(AHP and PROMETHEE). On one side, programming AHP calculations seems lighter, on the

other side PROMETHEE and other closed approaches look more appropriate when the

number of alternatives is higher than a few ones.

These overranking methods can anyway be used for studies as the one presented in § 6.1

by application of the method to an assessment of “distances” between alternatives and

associated costs.


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ANNEX 2. AHP (Analytic Hierarchy Process)

In the following, we will present AHP (hierarchy method founded by Saaty) and other close

hierarchy methods.

A2.1 Concepts of AHP

Saaty’s Analytic Hierarchy Process is a practical technique for modelling and solving multi-

criteria decision problems. AHP is a logical and structural framework, which allows improving

the performance of complex decisions by decomposing the problem in a particular

hierarchical structure. The incorporation of all the decision criteria retained, and their pairwise

comparison allows the decision maker to determine the trade-offs among objectives.

The application of the AHP method exploits two kinds of knowledge in the process of priority

setting to conceive the “boxes” of the network as well as to fix the weights:

• information gained from the expertise of the participants (subjective judgements, the regulations texts, knowledge from previous fires),

• measured (from tests when available) or calculated information (modelling).

AHP was first developed by Professor Thomas L. Saaty in the 1970’s and since that time has

received wide application in a variety of areas.

The first famous document on AHP is the book by Saaty (1980), “The Analytical Hierarchy

Process”. This book gives:

• a detailed presentation of the concepts of hierarchy, priority and judgement,

• the theoretical and mathematical foundations of the method,

• several examples of applications (e.g. to resource allocation, planning, conflict resolution …).

AHP was initially designed as a decision analysis tool to:

• Facilitate the development of logical hierarchical structures for complex decisions

• Quantify the opinions of subject area experts

• Assign weights to different functional areas relative to one another

• Assign weights to different technical capabilities relative to one another.


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In the classical Saaty’s AHP, decision makers supply pair-wise comparisons of various alternative “factors” on a ratio scale. These pair-wise comparisons capture decision maker’s subjective judgements and help in ranking a set of alternatives.

The AHP approach is based on three principles:

• Decomposition of the decision problem,

• Comparative judgement of the elements, and

• Synthesis of the priorities.

The pairwise comparison judgement is incorporated in forced reciprocal matrices. The

technique is based on matrix algebra, eigenvalues and eigenvectors.

A2.2 Theory and Methodology of AHP

A2.2.1 Weighting influences

Experts of the domain are asked to give measured or calculated weights, if it is meaningful

possible! The method compares, in a pairwise way, elements on the same level of the

hierarchy - for their influence on a box in a higher level -, indicating which element in the pair

is preferred and by what degree. Comparison of elements in pairs with respect to each

element of the next higher level is made on the basis of the scale of the following table A2.1.

Table A2.1. Scale for AHP weights

Numerical values

Equal preference 1

Weak preference 3

Preference 5

Very strong preference 7

Absolute preference 9

Intermediate values between the stated preferences

2, 4, 6, 8


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We need to ensure that the numbers given in the boxes are all on the same scale; otherwise

the weighted importance of the criteria won’t matter. To ensure the same scale is considered,

we normalize the numbers.

By combining all above information, we can finally get composite priorities for each of the

decision alternatives.

A2.2.2 Construction of matrices by pair-wise comparison

A simple example of hierarchy with three rows and a few boxes is represented at figure A2.2.

We assume that the experts have to estimate the weights with their own judgement (with no

measurement or calculation). E.g., at level 3, the most « precise » level in this example, the

weights of each strategy (Str 1, Str 2 and Str 3) has to be given for each objective (OB 1 and

OB 2). Let us consider the objective OB1. The following matrix is constructed on the basis of

ratios based on experts’ opinions, where all the possible pairs at row 3 are considered:

Figure A2.2. Example of a simple AHP structure.

(The thicker the arrow, the stronger the influence.)

STR 1 STR 2 STR 3

OB 1 OB 2

Policy


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The following matrix is constructed on the basis of ratios based on experts’ opinions, where

all the possible pairs at row 3 are considered:

Awaited properties:

aii = 1 ; i = 1, 3

aij = 1/aji ; i = 1, 3

A.r = 3×r, where r is a vector (r1, r2, r3)

In real world, some inconsistency may appear, e.g. aij can be more or less different of 1/aji

because these reports come from experts’ evaluation that may be not fully consistent. Saaty

introduced a “consistency vector”, a “consistency ratio, and a “consistency index” in order to

quantify these deviations and to be able to decide if they are acceptable or not. Saaty’s book

and other papers are presenting these concepts and the associated calculations. To give

here a brief presentation on the mathematical aspects off these concepts, we have taken the

following lines from the web pages of Dublin University on AHP where one can find a

numerical example (several examples are given too in Saaty’s book):

A2.2.3 Consistency Ratio (C.R.)

A consistency vector can be calculated by: calculating the row averages for the normalised

matrix to get weights multiplying the original matrix by the weights to get the product dividing

the product by the weights to get the consistency vector.

SAATY defines the consistency index (C.I.) as:

Where λ is the average value of the consistency vector, and n is the number of potential

decisions being compared.

3

3

2

3

1

3

3

2

2

2

1

2

3

1

2

1

1

1

rr

rr

rr

rr

rr

rr

rr

rr

rr

A =

1..

−−=nnIC λ


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For each matrix of size n, random matrices were generated and their mean C.I. value, called

the random index (R.I.), was computed. Using these values, the consistency ratio (C.R.) is

defined as the ratio of the C.I. to the R.I.; this C.R. is the measure of how a given matrix

compares to a purely random matrix in terms of the C.I.’s.

Here are some R.I. values for a given matrix dimension n:

n 2 3 4 5 6 7 8 9 10

R.I. 0 0.58 0.90 1.12 1.24 1.32 1.41 1.45 1.51

A value of the C.R. < 0.1 is typically considered acceptable; larger values require the

decision-maker to reduce the inconsistencies by revising judgements.

The following gives a short description of another method: “Hierarchical Cross-Impact

Analysis”, from [DONNEGAN 2002].

A2.3 Other AHP method: Hierarchical Cross-Impact Analysis

HCIA methodology

“Hierarchical Cross-Impact Analysis (HCIA) [DONEGAN et al.] is a multiattribute weighting

strategy developed at the University of Ulster using a similar philosophy to the Edinburgh

approach. According to DONEGAN, the characterisation of HCIA addresses the Cross-

Impact approach at two levels: a “fundamental” level and a “pragmatic” level.

In the fundamental level, a pseudo axiomatic approach is taken to:

- Define a hierarchy (in Fire safety),

- Explain the meaning of interactive importance,

- Propose the notion of partial impact,

- Define a global impact,

- Introduce sequential perturbations.


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In the pragmatic level a modelling approach is taken to:

- Maintain the assessment interval through each stage of the quantification

- Stretch the component ranking intervals to enhance the important components and decrease the psychological significance of the less-important components

- Perturb consensus weighting with interaction noise.

The partial impact of tactic Tj on component Ci relative to the rth objective Or is written as:

( )rOji TCI /∂ = ( )( )OrTTC iji //

The total impact of the collection of tactics on Ci relative to Or is defined as:

( ) ∑∑==

=∂nj

jrijnj

Oji tTCIr

,1,1/ σ ”

which is a matrix product. The components-to-objectives are defined by:

∑=

=nj

jrijri tn

OC,1

1/ σ

A drawback in HCIA is the absence of consistency check.

A2.4 Previous Applications of AHP to Fire Safety and Fire Protection

J. SHIELDS and G. SILCOCK presented in 1986 the AHP the applicability potential and

practicability of the AHP for use in safety planning and for determining fire safety priorities.

AHP was compared to an “Evaluation Points Scheme” for hospitals using a Delphi technique

(MARCHANT1984). The authors emphasised the fact that AHP takes into account all the

influences (on a given row and between rows) while the Evaluation Points Scheme

interactions and comparisons between elements on the same level are ignored. The practical

application the authors were thinking of is Fire Safety in dwellings and public assembly

buildings.


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They defined the following levels and “boxes”:

• Policy: Fire Safety.

• Objectives: Life Safety, Property Protection.

• Tactics: Ignition Prevention, Fire Control, Safe Egress, Rescue.

• Components: Occupants, Doors, Communications, Internal Planning, Travel Distance, Flues Ducts.

Further applications of AHP concepts and methods seem to have been carried out under the

names of “Fire Risk Evaluation” and “Fire Risk Index”.

A2.5 Research under work in AHP Methods

Research on the definition of better scale than 1,…, 9: Saaty’s scale may bring problems

because of the lack of steps, for example, between 1 and 2. It has been shown that, for

example, the use of the 99/1 scale (Ma and Zheng, 1991) or the balanced scale (Salo and

Hämäläinen, 1997) can give better results (Pöyhönen et al., 1997a).

Fuzzy logic can be used to deal with the Imprecision in Specification of Pair-wise

Comparisons on Ranking of Alternatives using Fuzzy Analytic Hierarchy Process (B.

Narasimha, Web Site of City University Hong Kong).

Genetic algorithms and other recent concepts are applied to hierarchy approach.

More generally, the concepts and methods in Decision-Making are having now such an

important place in management sciences that several kinds of applied research are trying to

bring together in newer tools the advantages of old or newer concepts.


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ANNEX 3. Cultural Heritage Fire risk index method

("Cultural heritage fire risk index", report by Fredrik Nystedt, September 2003)

The method is described in several reports and papers mainly from Nordic countries and UK, e.g. in : “Fire Risk Index Method – Multi-storey Apartment Buildings”, 2000, by Björn Karlsson and the report “Using a Delphi panel for developing a Fire Risk Index Method for MultiStorey Apartment Buildings” by Björn Karlsson and Daniel Larsson.

The paper by Sven Erik Magnusson and Tomas Rantatalo, Internrapport 7004, 1998: "Risk Assessment of Timberframe Multistorey Apartment Buildings. Proposal for a Comprehensive Fire Safety Evaluation Procedure", presents a method to verify the overall or general safety, taking into account structural fire endurance, design of fire protection systems, fire brigade capabilities as well as organisational and management factors. This is being achieved by means of an index system. The following lines come from this report.

The system is based on a hierarchy of fire safety decision-making levels (policy, objectives, strategies, parameters, survey items) with each level, e.g. objectives, being described in terms of the quantities defining the immediate lower level. The final result is a risk index describing overall fire safety policy as a function of 13 fire safety parameters. To prove the feasibility of the approach the methodology has been applied to fire risk ranking of multi-storey apartment buildings with wood frame and a frame of non-combustible material respectively. At least at this preliminary stage, the method looks very promising. One important aspect is that in practical use, the risk index calculation is extremely simple. The risk index assessment method is called FiRESEM.

The method used to produce the global or overall fire risk index mentioned above is generally called "multi-attribute evaluation". It is one of the most common and most powerful heuristic decision-making techniques, and an approach supported by a large body of knowledge described in the literature of decision analysis and management science. Multi-attribute evaluation is used to develop simplified but robust models of complex systems. Values are assigned to important attributes of the problem based on professional judgement and experience. These values are then operated on by some combination of arithmetic functions to arrive at a single score or index. The result is compared with other assessments or to a standard.

The second step of the safety evaluation scheme is the verification with respect to three individual fire safety and fire protection objectives:

provide life safety,

prevent fire spread out of compartment of origin,

prevent fire spread to next building.


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An obvious and appealing alternative for the evaluation of the three individual fire safety objectives is to employ successively the relevant part of the overall risk ranking system described above. The project team took the standpoint that a totally independent system of evaluation procedures was to be preferred. A number of well-developed and recognised risk assessment systems have therefore been reviewed with respect to their practical application to the individual fire safety objective. These systems include the FIRECAM method, the analytical FOSM (first order second moment) method developed at LTH, the L-curve method, the GRETENER method; the CRISPII-method developed at FRS, etc. To the extent that it has been natural and appropriate, more general engineering methods such as deterministic hazard calculation, application of the t-equivalent concept for structural fire endurance, the use of checklist procedures, etc have been reviewed with respect to practical usability.

A3.1. A Fire Risk Index for Cultural Heritage

An important contribution for FIRE-TECH is the recent report by Fredrik Nystedt (September 2003): "Cultural heritage fire risk index". A large part of this report is included in the present paragraph.

A3.1.1 Development of a risk index method

The first step is to identify the hierarchical levels. Table A3.1 shows a five-level hierarchy that has been used in many different applications (Watts, 1995).

Level Name Description 1 Policy Course or general plan of action adopted by an organisation to

achieve safety against fire and its effects 2 Objectives Specific fire safety goals to be achieved 3 Strategies Independent fire safety alternatives, each of which contributes

wholly or partly to the fulfilment of fire safety objectives 4 Parameters Components of fire risk that are determinable by direct or

indirect measure or estimate 5 Survey

items Measurable feature that serves as a constituent part of a fire safety parameter

Table A3.1. Decision making levels

The policy for fire safety in cultural heritage buildings could be that the level of fire safety should meet the requirements in the building regulations or that the safety level should show equivalence with other buildings in the same category. One objective could by “life safety”, with a strategy “to provide safe egress” with a parameter “detector system” and its survey item “type of detectors”.


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A3.1.2 Generalised procedure

A generalised procedure for ranking fire safety parameters to determine their relative importance is summarised in the following four steps (Watts, 1995).

Identify hierarchical levels of fire safety specification

Specify items compromising each level

Construct and assign values to matrices of each subsequent pair of levels

Combine matrices to yield importance ranking of items.

An example of step 1 is presented in Table A3.1. Step 2 requires lists of objectives, strategies parameters and survey items to be developed. The list of fire safety objectives might include statements on life safety, property protection, environmental protection, continuity of operations and heritage preservation. Strategies used to comply with the objectives are derived. Such strategies could involve ignition prevention, compartmentation, fire detection, fire suppression, etc. It is now possible to construct a matrix of objectives versus strategies, as shown in Table A3.2

Table A3.2. Matrix of objectives vs. strategies (example)

How important is each strategy to achieve each objective? In order to allow for mathematical computations, the values in the matrix can be normalised. If the policy vector is multiplied with the objectives/strategies vector, a new vector that shows the overall importance of each strategy to the fire safety policy. As the procedure continues the next step is to derive parameters for fire safety. Parameters as construction, height, compartmentation, building services, furnishings, equipment, special hazards, detection, alarm, smoke control, fixed suppression, fire department, egress system, personnel and management should be considered. A matrix of strategies versus fire safety parameters are constructed and evaluated. It is now possible to derive a vector illustrating the overall importance of each parameter to the fire safety policy.

Prevent ignition

Compartmentation Fire suppression

Life safety 2 1 2

Property protection

2 3 4


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Delphi work panel

As the risk index method allows the user to have moderate knowledge on the fundamentals of fire development and risk analysis, the development of the method must be done with state-of-the-art techniques. Many risk index methods were developed by the use of a Delphi work panel, as described by Linstone & Turoff (1975). They defined the Delphi technique as “a method for structuring a group communication process so that the process is effective in allowing a group of individuals, as a whole, to deal with a complex problem". In short, the technique is applied when a small monitor team designs a questionnaire that is sent to a larger respondent group. When the questionnaire is returned the monitor team summarises the results and, based upon the results, develops a new questionnaire for the respondent group. The respondent group is usually given at least one opportunity to re-evaluate its original answers based upon examination of the group response.

The task of the Delphi work panel is to assign weights to all objectives, parameters and strategies. As the process moves along, the answers from the Delphi panel could be used to gradually develop and improve the structure of the index method. Through matrix multiplication of the weights, a relative weight for each Parameter was derived, which allows a single index value for each building to be arrived at. This single index value can then be used for comparison with a similar building.

A3.2 Fictive example cultural heritage risk index method.

Policy

The policy is ensuring an acceptable level of property protection in order to preserve cultural heritage.

Evaluation of life safety of occupants is not included in this method, as it should be covered by adopting the national building regulations.

Objectives

There is one objective in the suggested method, i.e., to provide property protection in the compartment of origin, rest of the building and adjacent buildings.

Strategies

The objective of property protection is fulfilled by the following strategies:

Control fire growth Def. Controlling fire growth by using suppression systems, smoke control and the fire service (including staff response).

Confine fire by construction Def. Provide structural stability, control the movement of fire through containment, use of fire safe materials (passive fire protection).


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Establish safe rescue Def. Ensure safety of staff and fire service when they carry out rescue operations (fighting the fire, removing valuable objects, etc.)

It is necessary to value which importance a specific strategy in order to assign weights. This is done in a objectives vs. strategy matrix, shown below.

Strategy Objective:Property protection Normalised

Control fire growth 4 4/(4+2+2) = 0.5

Confine fire by construction 2 0.25

Establish safe rescue 2 0.25

Parameters

The following parameters are identified to play the most important role in fulfilling strategies.

Suppression system

Detection system

Smoke management

Compartmentation

Staff / fire service

A matrix on strategy vs. parameters is constructed and shown below.

Parameters Control fire growth

Confine fire by construction

Establish safe rescue

Suppression system 5 (0.36) 5 (0.3.1) 4 (0.27)

Detection system 3 (0.21) 3 (0.19) 3 (0.20)

Smoke management 2 (0.15) 3 (0.19) 4 (0.27)

Compartmentation 1 (0.07) 2 (0.12) 3 (0.20)

Staff / fire service 3 (0.21) 3 (0.19) 1 (0.06)

AUTOMATIC SPRINKLER SYSTEM

Type of sprinkler (N = no sprinkler, R = residential sprinkler, O = ordinary sprinkler) and Location of sprinkler (A = in apartment, E = in escape route, B = both in apartement and escape route)


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SURVEY ITEMS DECISION RULES

type of sprinkler N R R R O O O

location of sprinkler - A E B A E B

Grade N M L H M L H

(N = no grade, L = low grade, M = medium grade and H = high grade)

PORTABLE EQUIPMENT

N None

F Extinguishing equipement on every floor

A Extinguishing equipement in every apartment

PARAMETER GRADE

SUB-PARAMETERS DECISION RULES

Automatic sprinklers

system

N N N L L L M M M H H H

Portable equipment N F A N F A N F A N F A

GRADE 0 0 1 1 1 2 4 4 4 5 5 5

(Minimum grade = 0 and maximum grade = 5)


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Sub-parameters

Each parameter is divided into sub-parameters in order to make possible to assign a specific grade (0-5) to the parameter. Here is an example with the parameter “suppression system”.

Calculating weights

The information in the matrices is used to derive a new matrix where on policy vs. parameters. The complete process is described in the WG6 report.

Parameter Weights to fulfil the policy

Suppression system 0.5x0.36 + 0.25x0.3.1 + 0.25x0.27 = 0.325

Detection system 0.5x0.21 + 0.25x0.19 + 0.25x0.20 = 0.203

Smoke management 0.5x0.15 + 0.25x0.19 + 0.25x0.27 = 0.190

Compartmentation 0.5x0.07 + 0.25x0.12 + 0.25x0.20 = 0.115

Staff / fire service 0.5x0.21 + 0.25x0.19 + 0.25x0.06 = 0.167

Figure A3.3. Example of a complete process

Calculating risk index

The risk index is calculated with the following expression:

1

n

i ii

R w g=

=∑

where iw is the weight for a specific parameter and ig is its grade.


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A3.3 Conclusions

It would be useful to have a cultural heritage fire risk index method available. The index method could be used to give a quick and rough estimate of the fire performance of a large quantity of buildings. The National Property Board could use the risk index to rank which buildings that have the best and the poorest fire safety. However, the method cannot be used to show the exact level of risk, as it very difficult to establish which level of the risk index that is considered acceptable. The risk index will only tell how safe the building is compared to others, i.e., a relative measure of safety. If it is of interest to have a quantified measure of the fire safety, a quantitative risk analysis is preferred. The QRA should also be used when different fire safety alternatives are evaluated. The risk index method identifies the cultural buildings where a more extensive analysis of their fire performance is needed. It is, however, possible to use the risk index to evaluate to which parameter a change is needed to improve the overall fire safety performance.

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