Risk analysis for fire: the case of civil structures

CORSO DI PROGETTAZIONE STRUTTURALE ANTINCENDIO
Analisi del rischio: il caso
dell’incendio di strutture civili
Konstantinos Gkoumas, Ph.D., P.E.
Franco Bontempi, Ph.D., P.E.
Facoltà di Ingegneria
Sapienza Università di Roma
www.francobontempi.org October 28 2014 1

Index
• System approach to fire safety design
• Risk/fire risk/risk analysis
• Risk assessment process
• Risk analysis
• Hazard analysis
• Risk acceptance
• Risk reduction
• References
www.francobontempi.org
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ANALISI DEL RISCHIO:
IL CASO DELL’INCENDIO
DI STRUTTURE CIVILI

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• System approach to fire safety design
• Risk
- fire risk
- risk types
- risk analysis
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System approach to fire safety design
0 OBJECTIVE prevention
suppression
STOP FIRE FIRE SPREAD
MINOR
SPREAD
Y
MAJOR
SPREAD
STRUCTURAL
INTEGRITY
AVOID
CASUALITIES
LOCALISED
DAMAGE
STRUCTURAL
FAILURES
N
mitigation
Y
N
fire safe design
Y
N
FIRE
robust design
Y
N
MAJOR
COLLAPSE
AVOID
DIRECT
DAMAGE
AVOID
COLLAPSE
1
2
3
4
fire safety design -
structural
fire safety design -
non structural
GLOBAL
SAFETY
LOSS OF
GLOBAL
SAFETY
AVOID
INDIRECT
DAMAGE
Y N
The fire safety is framed in different
“safety levels”, corresponding to
different safety objectives.
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(Fire) Risk Estimation*
*(following SFPE Handbook of Fire Protection Engineering)
Provide answer to the following questions
1. What could happen?
2. How bad would it be if it did happen?
3. How likely is it to happen
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What is risk?
Risk can be defined as the probability that the harm or damage from a particular
hazard is realized.
Risk is measured in terms of consequences and likelihood (a qualitative description
of probability or frequency). In mathematical terms risk can be defined as:
risk = f (frequency or probability, consequence) (1)
In the case of an activity with only one event with potential consequences, a risk (R)
is the probability (P) that this event will occur multiplied with the consequences (C)
given the event occurs:
R = PC (2)
The risk of a system is the sum of the risks of all harmful events of that system:
(3)
푛
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푅푆 = 푅푖
푖=1
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Risk types
• Life safety risks are normally presented in two ways:
- Individual risk and
- Societal risk
• Individual risk:
The purpose of the individual risk is to ensure that individuals in the society
are not exposed to unacceptably high risks. It can be defined as the risk to any
occupant on the scene for the event/hazard scenario i.e. it is the risk to an
individual and not to a group of people.
• Societal risk:
Societal risk is not looking at one individual but is concerned with the risk of
multiple fatalities. People are treated as a group, there are no considerations
taken to the individuals within the group i.e. the definition of the risk is from a
societal point of view.
Source: Jönsson, 2007
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What is risk analysis?
• A big family of different approaches, methods
and complex models combining various
methododical components for specific tasks
• Systematic analysis of sequences and interaction
effects in potential accidents, thereby identifying
weak points in the system and recognizing
possible improvement measures
• Risk analysis makes the quantification of risks
feasible
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The risk assessment process
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The risk assessment process
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Start
Definition of the system
Hazard identification
Probability analysis Consequence analysis
Additional safety
measures
Risk estimation
Risk evaluation Risk criteria
Acceptable
risk?
Stop
Risk analysis
Risk evaluation
YES
NO
Risk reduction
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Definition of the system (context establishment)
Define the operational environment and the context of the risk assessment
process
– Definition of the scope or the risk assessment process
• This includes determining the timeframe (e.g. from planning to dismantling),
the required resources and the depth of analysis required.
– Definition of the strategic and organizational context
• The nature of the organization in charge of the risk management and the
environment in which it operates is established
– Identification of the stakeholders and objectives
• The relationships that are interdependent with the organization are defined, the
impacts that might occur are accounted for, as well as and what each is wanting
out of the relationship
– Determination of the evaluation criteria
• Decide what level of risk the organization is prepared to accept
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a. What can happen
b. How can it happen
Means for hazard identification:
• Decomposition of the system into a number of
components and/or subsystems
• Identification of possible states of failure for the
considered system and sub-systems
• Identification of how the hazards might be realized
for the considered system and subsystems
Source: Faber, 2008
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Hazard identification – system decomposition
(a) Main cables
(b) Anchor systems
(e) Railway girder
(f) Highway girders
(g) Expansion joints
2. Secondary comp.
(a) Hanger ropes
(b) Buffers
(c) TMD
(d) H.R. attachments
(e) Bitumen
(e) Plastic
(b) Mechanical
(a) Private
(a) Private
3. Exceptional traffic
(a) Highway
3. Under the bridge
2. Communications
2. Social
(a) Bridge authorities
(b) Goverment
(c) Region
2. Aspects
(a) Financial
(c) Maintenance
3. Policies
(a) Technical
1. Monitoring
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A. Structure
1. Main components
(c) Towers
(d) Foundations
(h) Cable saddle
(e) Non str.elements
3. Materials
(a) Steel
(b) Concrete
(c) Prestressed c.
(d) Alluminium/iron
(f) Coating
4. Systems
(a) Electrical
(c) Hydraulics
B. Users
1. Highway traffic
(b) Commercial
2. Railway traffic
(b) Commercial
(a) Heavy
(b) Hazard mat.
(c) Military
C. Facilities
1. Over the bridge
(b) Railway
2. By the bridge
(a) Highway
(b) Railway
(c) Toll booths
(d) Control center
(e) Parking
(a) Maritime traffic
D. Dependencies
1. Power
3. Financial
4. Supplies
5. Emerg. Responce
(a) First aid
(b) Police
(c) Fire brigade
(d) Hospitals
6. Ext. Contractors
E. Linkage
1. Economy
3. Military
F. Operation
1. Authorities
(b) Management
5. Personnel
(b) Other
G. Technology
(a) GPS
(b) Accelerometers
(c) Strain gauges
(d) Seismographs
(e) Thermometers
(f) WIM
(g) CCTV
(h) Field equipment
2. Control
(a) Cable control
(b) TMD
(c) Highway traffic
(d) Railway traffic
3. Data transmission
(a) Cable
(b) Wireless
4. Computer center
(a) Hardware
(b) Software
(c) Data bases
(d) Internet/LAN
4. Regulations
4. Location
(c) External
Hierarchical Holographic Models (HHM)
(Defined in Haimes, 1981)
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Risk analysis: hazard identification
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• Qualitative methods
Studies based on the generic experience of personnel and do not
involve mathematical estimations.
• Quantitative methods
Mathematical estimations that rely upon historical evidence or
estimates of failures to predict the occurrence of an event.
• Semi-quantitative methods
Combination of the above (mostly, qualitative methods with
applied numerical values).
Source: Nolan, D. P. Handbook of Fire and Explosion Protection
Engineering Principles for Oil, Gas, Chemical, and Related Facilities, 1986
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Risk analysis: hazard identification
Source: Aven, T. Risk Analysis: Assessing Uncertainties beyond Expected Values and Probabilities.
John Wiley & Sons, 2008
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Hazard identification. Qualitative Methods
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Checklist or Worksheet
A standardized listing which identifies common protection features required for typical
facilities is compared against the facility design and operation. Risks are expressed by
the omission of safety systems or system features.
Preliminary Hazard Analysis (PHA)
Each hazard is identified with potential causes and effects. Recommendations or known
protective measures are listed.
What-If analysis
A safety study which by which “What-If’ investigative questions (brainstorming
approach) are asked by an experienced team of a hydrocarbon system or components
under examination. Risks are normally expressed in a qualitative numerical series (e.g., 1
to 5).
HAZOP - HAZard and OPerability analysis (analisi di pericolo e operabilità)
A formal systematic critical safety study where deviations of design intent of each
component are formulated and analyzed from a standardized list. Risks are typically
expressed in a qualitative numerical series (e.g., 1 to 5) relative to one another.
Source: Nolan, D.P. 1986. Handbook of Fire and Explosion Protection Engineering Principles for …. Noyes, New Jersey
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Hazard identification. Qualitative Methods
Event Trees (ET) –albero degli eventi
A mathematical logic model that mathematically and graphically
portrays the combination of events and circumstances in an
accident sequence, expressed in an annual estimation.
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Fault Trees (FT) – alberi dei guasti
A mathematical logic model that mathematically and graphically
portrays the combination of failures that can lead to a specific main
failure or accident of interest, expressed in an annual estimation.
Failure Modes and Effects Analysis (FMEA)
A systematic, tabular method of evaluating the causes and effects
of known types of component failures, expressed in an annual
estimation.
Source: Nolan, D.P. 1986. Handbook of Fire and Explosion Protection Engineering Principles for …. Noyes, New Jersey
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• Risk analysis
• Qualitative risk analysis
• Quantitative risk analysis
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Risk analysis
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• Risk analysis
– Probability- as the likelihood of the risk occurrence
– Impact - consequences if the risk occurs
• risk proximity, meant as the point in time during which
a risk will impact
• Risk analysis - methods
– Qualitative Risk Analysis, in which numbers and
probabilities are used not extensively or at all
– Quantified Risk Analysis (QRA)
– Probabilistic Risk Analysis (PRA), in which the system risk
is represented as a probability distribution
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Risk analysis and system complexity
Analysis
Methods
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High-Probability/
Low-Consequences
(HPLC)
Low-Probability/
High-Consequences
(LPHC)
Stochastic
Complexity
Deterministic
Qualitative
Risk
Analysis
Quantitative/Probabilistic
Risk
Analysis
Pragmatic
Risk
Scenarios
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Qualitative Risk analysis
• Qualitative Risk Analysis is the simplest method of risk analysis, and
generally is used during the preliminary analysis phases.
• It consists in using subjective assessments of risks, and consequently, in
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ranking them in a subjective manner.
• Sources for information to be used in the analysis can be drown from
previous experiences, history of events and consultation of experts.
• The ranking of risks is qualitative, e.g. risk (1) > risk (2) > risk (3),
while a description can be added. Eventually, a likelihood-consequence
matrix can be constructed.
• The biggest drawback of QRA is that there is neither a clear indication
of the risk’s magnitude nor an absolute scale of how serious the risk
might be, so, for a comprehensive risk analysis of more complex
systems, quantitative methods should be preferred.
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Qualitative risk analysis methods: risk matrix
• A risk matrix typically provides a discrete partitioning of relative consequences
along one dimension and relative likelihood along the other.
• The entry in each matrix cell may include a description of hazards known or
believed to have that combination of consequence severity and likelihood.
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Source: NFPA, SFPE Handbook of
Fire Protection Engineering,
3rd edition, 2002
Source: Furness, A., Muckett, M.
Introduction to Fire Safety
Management. Elsevier, 2007.
23

Qualitative risk analysis methods: SWOT analysis
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Strengths: characteristics of the
business or project that give it an
advantage over others.
Weaknesses: characteristics that
place the business or project at a
disadvantage relative to others
Opportunities: elements that the
project could exploit to its
advantage
Threats: elements in the
environment that could cause
trouble for the business or project

Quantitative Risk analysis
• Quantified (or quantitative) Risk Analysis (QRA) combines
the consequences and frequencies of accident scenarios to
estimate the level of risk.
• In respect to the Qualitative method, QRA implicates the
acquaintance of probabilities that describe the likelihood of
the outcomes and their consequences.
• QRA started with the chemical industries from the 70s and
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the offshore industry from the 80s.
• QRA is traditionally expressed through the decomposition
of the system. This frequently is done by the use of event
trees and fault trees.
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FTA and ETA
• ETA (event tree analysis) provides a structure for
postulating an initiating event and analyzing the
potential outcomes
• FTA (fault tree analysis) begins with a failure
and provides a structure to look for potential
causes
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Event tree analysis
• Event trees pictorially represent the logical order in which
events in a system can occur. Event trees begin with an
initiating event, and then the consequences of the event are
followed through a series of possible paths.
• Each path is assigned a probability of occurrence. Therefore,
the probability of the various possible outcomes can be
calculated.
• Event tree analysis is based on binary logic, in which an
event has either happened or not, or a component has failed
or has not.
• It is valuable to analyze the consequences arising from a
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failure or undesired event.
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Event tree analysis: illustration (1)
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Event trees are helpful in
considering all the possible
outcomes (on the right-hand side)
from an initiating event (on the
left-hand side), which is usually
ignition for fire risks.
The frequency of the initiating
event can be estimated from fire
report data, and the conditional
probabilities of the sub-events can
be quantified from fire report data
or fault trees.

Event tree analysis: illustration (2)
Source: Fire Risk in Metro Tunnels and Stations Hyder Consulting
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Fault tree analysis
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Fault trees are helpful in
quantifying the
probability of a top
event of concern (such
as the failure of a fire
protection system) from
all the potential root
causes (at the bottom),
again quantified from fire
report data.

Fault tree analysis
general conclusion (event)
• Fault trees look like a complement
to event trees.
• The idea is to begin with a general
conclusion (event) and, using a
top-down approach, to generate a
logic model that provides for both
qualitative and quantitative
evaluation of the system
reliability.
Source: google pictures search “Fault tree”
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Fault tree analysis - symbols
Basic event - failure or error in a system component or element
(example: switch stuck in open position)
Initiating event - an external event (example: bird strike to aircraft)
Undeveloped event - an event about which insufficient information is
available, or which is of no consequence
Conditioning event - conditions that restrict or affect logic gates
(example: mode of operation in effect)
Intermediate event: can be used immediately above a primary event to
provide more room to type the event description.
Source: Fault Tree Handbook. Nuclear Regulatory Commission. NUREG–0492
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Fault tree analysis – gate symbols
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OR gate - the output occurs if any input occurs
AND gate - the output occurs only if all inputs occur (inputs are
independent)
Exclusive OR gate - the output occurs if exactly one input occurs
Priority AND gate - the output occurs if the inputs occur in a specific
sequence specified by a conditioning event
Inhibit gate - the output occurs if the input occurs under an enabling
condition specified by a conditioning event
Source: Fault Tree Handbook. Nuclear Regulatory Commission. NUREG–0492
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Advantages and disadvantages of FTA
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• Disadvantages
1. There is a possibility of oversight and omission of significant failure
modes.
2. It is difficult to apply Boolean logic to describe failures of system
components that can be partially successful in operation and thereby
affect the operation of the system, e.g. leakage through a valve.
3. For the quantitative analysis there is usually a lack of pertinent failure
data. Even when there are data they may have been obtained from a
different environment.
• Advantages
1. It provides a systematic procedure for identifying faults that can exist
within a system.
2. It forces the analyst to understand the system thoroughly.
Source: Hasofer et al. 2007, Risk Analysis in Building Fire Safety Engineering
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Cause – consequence diagrams
• The combination of fault trees and event trees leads to the creation of
Iniziative event
Consequences
S1
S2
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cause-consequence diagrams.
Time
Revealed from the
Monitoring system
S3
Infraction of traffic law
Improper speed
Road condition
Vehicle flow
blocked
YES
YES
NO
NO
Other
Road
Accident
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Quantified Risk Analysis: cause – effect diagrams
SCENARIO PROBABILITY
A1 PA*P1
A2 PA*(1-P1) *P2 *P3
A3 PA*(1-P1) *P2*(1-P3 )
A4 PA*(1-P1) *(1-P2)*P3
A5 PA*(1-P1) *(1-P2)*(1-P3)
B1 PB*P1
B2 PB*(1-P1) *P2 *P3
B3 PB*(1-P1) *P2*(1-P3 )
B4 PB*(1-P1) *(1-P2)*P3
B5 PB*(1-P1) *(1-P2)*(1-P3)
C1 PC*P1
C2 PC*(1-P1) *P2 *P3
C3 PC*(1-P1) *P2*(1-P3 )
C4 PC*(1-P1) *(1-P2)*P3
C5 PC*(1-P1) *(1-P2)*(1-P3)
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Triggering
event
Fire
ignition
1. Fire
extinguished
by personnel
2. Intrusion of
fire fighters
Arson
Short
circuit
Explosion
Cigarette
fire
YES (P1)
NO (1-P1) YES (P2)
NO (1-P2)
Scenario
Other
A1
A2
A3
A4
A5
3. Fire
suppression
YES (P3)
NO (1-P3)
YES (P3)
NO (1-P3)
Fire
location
AREA A
(PA)
YES (P1)
NO (1-P1) YES (P2)
NO (1-P2)
B1
B2
B3
B4
B5
YES (P3)
NO (1-P3)
YES (P3)
NO (1-P3)
AREA B
(PB)
YES (P1)
NO (1-P1) YES (P2)
NO (1-P2)
C1
C2
C3
C4
C5
YES (P3)
NO (1-P3)
YES (P3)
NO (1-P3)
AREA C
(PC)
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F (frequency) – N (number of fatalities) curve
• An F–N curve is an alternative way of describing the
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risk associated with loss of lives.
• An F–N curve shows the frequency (i.e. the expected
number) of accident events with at least N fatalities,
where the axes normally are Logarithmic.
• The F–N curve describes risk related to large-scale
accidents, and is thus especially suited for
characterizing societal risk.
Source: Aven, T. Risk Analysis: Assessing Uncertainties beyond Expected Values and Probabilities. John Wiley & Sons, 2008
37

Source: Aven, T. Risk Analysis: Assessing Uncertainties beyond Expected Values and Probabilities. John Wiley & Sons, 2008
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Source: NFPA, SFPE Handbook of Fire Protection Engineering, 3rd edition, 2002
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Index
• Risk acceptance
- ALARP
- Human life (!)
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Risk acceptance
Source: Persson, M. Quantitative Risk Analysis Procedure for the Fire Evacuation of a Road Tunnel -An Illustrative Example. Lund, 2002
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Risk acceptance – ALARP (1)
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RISK MAGNITUDE
INTOLERABLE
REGION
As
Low
As
Reasonably
Practicable
BROADLY ACCEPTABLE
REGION
Risk cannot be justified
in any circumstances
Tolerable only if risk
reduction is impracticable
or if its cost is greatly
disproportionate to the
improvement gained
Tolerable if cost of
reduction would exceed
the improvements gained
Necessary to maintain
assurance that the risk
remains at this level
As
Low
As
Reasonably
Achievable
42

Risk acceptance – ALARP (2)
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Source: google pictures search “ALARP”
43

Monetary values – cost of human life (!)
• What is the maximum amount the society (or the decision-maker) is willing
to pay to reduce the expected number of fatalities by 1?
• Typical numbers for the value of a statistical life used in cost-benefit analysis
are 1–10 million euros. The Ministry of Finance in Norway has arrived at a
value at approximately 2 million euros.
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Guideline values for the cost to
avert a statistical life (euros), used
by an oil company
Source: Aven, T. Risk Analysis: Assessing
Uncertainties beyond Expected Values and
Probabilities. John Wiley & Sons, 2008
44

F-N diagrams: case study on a 180m road tunnel
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1 20MW Fire [fat+inj/year] 0.00E+00
2 100MW Fire [fat+inj/year] 0.00E+00
3 Bleve of 50kg propane cylinder [fat+inj/year] 0.00E+00
4 Motor spirit pool fire [fat+inj/year] 0.00E+00
5 VCE of motor spirit [fat+inj/year] 0.00E+00
6 Chlorine release [fat+inj/year] 0.00E+00
7 BLEVE of 18t propane tank [fat+inj/year] 0.00E+00
8 VCE of propane [fat+inj/year] 0.00E+00
9 Propane torch fire [fat+inj/year] 0.00E+00
10 Ammonia Release [fat+inj/year] 0.00E+00
11 Acrolein in bulk release [fat+inj/year] 0.00E+00
12 Acrolein in cylinder release [fat+inj/year] 0.00E+00
13 BLEVE of a 20t CO2 tank [fat+inj/year] 0.00E+00
All scenarios [fat+inj/year] 0.00E+00
1+2 20MW - 100MW FIRES [fat+inj/year] 0.00E+00
3+13 BLEVE (except propane in bulk) [fat+inj/year] 0.00E+00
4+5 Flammable liquids [fat+inj/year] 0.00E+00
6+10+11+12 Toxic products [fat+inj/year] 0.00E+00
7+8+9 Propane in bulk [fat+inj/year] 0.00E+00
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F-N diagrams: case study on a 180m road tunnel
퐸푉 =
푛
푖=1
푓푖 ∙ 푁푖
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퐹푁 =
푛
푖=1
푓푖
EVENT
Event
Frequency
Event
Consequence
Cumulative Frequency
(per year)
E1 f1 N1
F1 = f1
E2 f2 N1 F2 = f1 + f2
E3 f3 N2 F3 = f1 + f2 + f3
E4 f4 N4 F3 = f1 + f2 + f3 + f4
..... ..... ..... .....
En fn Nn Fn = f1 + f2 + f3 + f4+.....+ fn

Case study: 180m road tunnel
Individual Risk
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Trial 1 BASIS calculation
Trial 2 Total traffic [veh/h] 7200 72000
HGV ratio [-] 0.01 0.99
TrDen (traffic density) [-] 0.78 3.79
Bus/Coaches ratio [-] 0.01 0.99
HGV ratio [-] 0.01 0.99
Bus/Coaches ratio [-] 0.01 0.99
Trial 3
Trial 5
Trial 6 Light vehicles average speed [km/h] 80 179
Trial 7 HGV/Bus average speed [km/h] 60 119
Trial 8 Delay for stopping approaching traffic [s] 9000 1
Trial 9 Area (Urban/Rural) [-] urban rural
Trial 10 Average density of population [hab/km2] 0.01 999000
Trial 11 DG-HGV traffic [veh/h] 5 10000
Trial 12 Average number of people in a light vehicle [-] 2 10
Trial 13 W (effective width) [m] 10 5
Trial 14 H (effective height) [m] 6 3
Trial 15 VnN (volume flow rate along tunnel at nodes) [m3/s] 120 0
Trial 16 VnE (volume flow rate along tunnel at nodes) [m3/s] 210 0
Trial 17 tE (Time taken to activate emergency ventilation) [mins] 0.2 60
Trial 18 Xe (average spacing between emergency exits) [m] 90 1000
Trial 19 Cam (camber) [%] 0 100
Trial 20 Ad (open area of discrete drains) [m2] 0.075 0
Trial 21 Ecom (emergency coms) → 1, 2 o 3 [-] 3 1
Type of construction → 1 o 2 [-] 2 1
trad (internal radius) [m] - 6
dlin (lining thickness) [m] - 0.3
trad (wall thickness) [m] 0.2 -
dlin (roof slab thickness) [m] 0.2 -
Ns (Number of segments) [-] 6 15
Xs (Segment lengths) [m] 30 12
Nsub (number of sub-segments per segment) [-] 3 2
total number of sub-segments [-] 18 30
Xsub (actual sub-segment lengths) [m] 10 6
Trial 24 Number of lanes [-] 2 5
Trial 4
Trial 22
Trial 23
1 20MW Fire [fat+inj/year]
2 100MW Fire [fat+inj/year]
3 Bleve of 50kg propane cylinder [fat+inj/year]
4 Motor spirit pool fire [fat+inj/year]
5 VCE of motor spirit [fat+inj/year]
6 Chlorine release [fat+inj/year]
7 BLEVE of 18t propane tank [fat+inj/year]
8 VCE of propane [fat+inj/year]
9 Propane torch fire [fat+inj/year]
10 Ammonia Release [fat+inj/year]
11 Acrolein in bulk release [fat+inj/year]
12 Acrolein in cylinder release [fat+inj/year]
13 BLEVE of a 20t CO2 tank [fat+inj/year]
All scenarios [fat+inj/year]
1+2 20MW - 100MW FIRES [fat+inj/year]
3+13 BLEVE (except propane in bulk) [fat+inj/year]
4+5 Flammable liquids [fat+inj/year]
6+10+11+12 Toxic products [fat+inj/year]
7+8+9 Propane in bulk [fat+inj/year]
Societal Risk
EV (Expected Value of the dead)
Societal Risk
30m (distance from the route) [fat+inj/year]
80m [fat+inj/year]
200m [fat+inj/year]
500m [fat+inj/year]
30m [fat+inj/year]
80m [fat+inj/year]
200m [fat+inj/year]
500m [fat+inj/year]
Individual Risk
Direction A
Direction B
4 analysis for every trial
Grouping

Risk reduction
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48

Risk reduction
Source: Brussaard et al. 2004. The Dutch Model for the Quantitative Risk Analysis of Road Tunnels.
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49

Risk reduction (2) - monitoring and system response
Accident evolution Monitoring
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Time
1
2
3
Accident Accident evolution
Pre-accident
situation
Pre-accident
Monitoring
Pre-accident
System Response
Accident
Localization
Evolution of System Response
System
Response
50

References
• NFPA, SFPE Handbook of Fire Protection Engineering, 3rd edition, 2002
• Jönsson, J. Combined Qualitative and Quantitative Fire Risk Analysis – Complex Urban Road Tunnel. Arup partners, 2007.
• Faber, M.H. (2008) Risk and Safety in Civil, Environmental and Geomatic Engineering. ETH Zürich, lecture notes, available
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online on 01/2011 at: http://www.ibk.ethz.ch/fa
• Haimes, Y. Y. (1981). Hierarchical holographic modeling. IEEE Transactions on Systems, Man, and Cybernetics, 11(9), pp.
606– 617.
• Nolan, D.P. 1986. Handbook of Fire and Explosion Protection Engineering Principles for Oil, Gas, Chemical, and Related
Facilities. Noyes, New Jersey
• Aven, T. Risk Analysis: Assessing Uncertainties beyond Expected Values and Probabilities. John Wiley & Sons, 2008
• Furness, A. , Muckett, M. Introduction to Fire Safety Management. Elsevier, 2007.
• Fire Risk in Metro Tunnels and Stations, Hyder Consulting, available on 05.2011 at
http://hkarms.myftp.org/web_resources/Conference_Presentation/Fire_Risk_Metro_Tunnels_Stations.pdf
• Fault Tree Handbook. Nuclear Regulatory Commission. NUREG–0492
• Hasofer et al. 2007, Risk Analysis in Building Fire Safety Engineering
• Persson, M. Quantitative Risk Analysis Procedure for the Fire Evacuation of a Road Tunnel -An Illustrative Example. Lund,
2002
• Brussaard et al. 2004. The Dutch Model for the Quantitative Risk Analysis of Road Tunnels. Available on 05.2011 at
http://www.rws.nl/rws/bwd/home/Tunnelveiligheid/dutch%20model.pdf
• Gkoumas, K. 2008. Basic aspects of risk-analysis for civil engineering structures. Handling Exceptions in Structural
Engineering: Robustezza Strutturale, Scenari Accidentali, Complessità di Progetto, Roma, 13-14 novembre.
http://www.francobontempi.org/handling_papers.php
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Risk analysis for fire: the case of civil structures

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