Transcript Slide 1

This project is funded by the European Union
Projekat finansira Evropska Unija
INTRODUCTION TO RISK
ASSESSMENT AND
MANAGEMENT
Antony Thanos
Ph.D. Chem. Eng.
[email protected]
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Risk assessment
• The procedure of evaluation of risk level
• The heart of Safety Report and Safety
Management System
• Basic Terms in Risk Assessment
 Hazard
 Accident
 Consequence
 Risk
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard definitions
 Generic : State, action or physical/chemical
characteristic with potential of harm to
equipment, human health or the environment
 Seveso III Directive (art.3 para.14) : “the intrinsic
property of a dangerous substance or physical situation,
with a potential for creating damage to human health or
the environment”
 Rulebook : “intrinsic properties of dangerous
substances or a set of certain circumstances in relation
to dangerous substances which may cause harmful
effects for human health and environment”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Common characteristics for hazard definitions :
 hazard relates to potential of harm, not to
necessity or to probability (high/low) of hazard
to be expressed (accident)
 hazard is related to effects on human health
and environment
• In Seveso Directive and Rulebook, indirectly
relation of hazard to equipment damage via
Domino effects analysis
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard examples :
 Work at height – Hazard of fall
 Toxic material handling (e.g. production of NH3)
o Toxic release (e.g. failure of pipe)
o Dispersion of released NH3 to the
atmosphere
o Toxic effects to human via inhalation of toxic
substance
• Hazard source example : mechanical failures, e.g.
corrosion, weld defects
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident definitions
 Generic : The event that leads to harm to
human, environment or equipment
 Seveso III Directive art.3 para.13 : “major
accident means an occurrence such as a major
emission, fire, or explosion resulting from uncontrolled
developments in the course of the operation of any
establishment covered by this Directive, and leading to
serious danger to human health or the environment,
immediate or delayed, inside or outside the
establishment, and involving one or more dangerous
substances”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident probability : The probability of evolution of
a hazard to an accident
 Hazard : natural gas equipment (e.g. valve)
 Accident : leak from valve stem with ignition (jet
flame)
 Probability of accident : 10-4 per year
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Consequence : The outcome (effect) of an
accident, as for example:
 Injury from fall from height
 Pulmonary damage due to inhalation of
released NH3
 Burns from thermal radiation of fire in gasoline
tank
• Consequence analysis : the procedure applied for
calculation of the extent of accidents effects
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• The effect levels have to be defined (e.g. death, 1st
degree burn, collapse of house) for estimation of
extent of consequences
• Extent of consequences is usually estimated as
distance from accident centre for the expected
effect level
• Consequence results presentation usually in
graphs, tables, maps
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Relation of Hazard Identification / Accident /
Consequence analysis
 Hazard identification : Use of techniques for
identifying hazards, causes of accidents and
effects
 Accidents usually related with primary
hazardous substance release via Loss of
Containment (LoC)
 Hazard identification usually specify release
expected and not final accident (top event)
 Top event required for consequence analysis
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Relation of Hazard Identification / Accident /
Consequence analysis (cont.)
 Hazard identification result example :
o Leak of LPG from transfer pump seal
 Top event accidents examples :
o Jet flame from leak of LPG from pump seal
o Flash fire from leak of LPG from pump
 Consequence analysis results examples :
o Thermal radiation 1500 TDUs at 50 m from LPG
pump
o Low Flammability Level at 180 m downwind LPG
pump location
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Risk : The probability of cause of harm from
accident
• Risk expression example :
 The probability of death from fall of lightning in
country XYZ is 10-7 per year (1 person per
10.000.000 persons will die from lightning per
year in country XYZ)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Individual Risk : Risk of certain level of harm from
accident, at specific location, independent of
number of affected subjects
 Example : The risk of lethal effects from thermal
radiation from pool fire in gasoline tank TK-123
of factory ABC is calculated as 10-6 per year at a
distance of 100 m from tank. No interest on
how many people can be present in 100 m
location.
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Societal Risk :
 Relationship between frequency of accident
and number of people suffering from a
specified level of harm in a given population
from the realisation of specified accidents
 Concerns estimation of the chances of more
than one individual being harmed
simultaneously by an incident
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Societal Risk expression example (F/N curve
related to guide curve of societal risk, Netherlands)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Seveso III Directive definition of risk
 art.3 para.15 : “risk means the likelihood of a
specific effect occurring within a specified
period or in specified circumstances”
 No reference to quantitative or qualitative
expression of risk
 No reference to severity of effect (injury, lethal
effects etc.)
 No reference to individual or societal risk
 No reference to risk acceptance criteria
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Rulebook references to risk :
 “The probability shall be numerically or
descriptively expressed as low, medium and
high…
 Accident risk shall be assessed on the basis of
accident probability and potential
consequences. Chemical accident risk shall be
expressed as: negligible, low, medium, high and
very high, in accordance with criteria shown in
the following table…”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Generic Risk Analysis Framework
Hazard
Identification
Accident
Scenarios
Risk reduction
measures
Consequence
Analysis
Accident
Probability
NO
END
YES
Accepted
Risk
Risk
Assessment
• Which are the requirements of Seveso Directive ?
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive
 art.10 para.1.b : “Demonstrating that majoraccident hazards and possible major-accident
scenarios have been identified and that the
necessary measures have been taken to
prevent such accidents and to limit their
consequences for human health and the
environment.”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive (cont.)
• art.10 para.1.c : “Demonstrating that adequate
safety and reliability have been taken into
account in the design, construction, operation
and maintenance of any installation, storage
facility, equipment and infrastructure
connected with its operation which are linked to
major-accident hazards inside the
establishment.”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive (cont.)
 Demonstration
o Justification (convince assessor) of results
o No absolute proofs possible / Uncertainty
expected on results
o Professional judgement expected on
credibility of results
o Evidence that a systematic methodology is
used (direct relation with Safety
Management System requirement for risk
assessment and management of change)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive (cont.)
 Demonstration
 The level of demonstration should be
proportionate to the extent of potential
consequences and the complexity of the
installation/process/systems involved.
o Common approach in Major Accident
Hazard Bureau (MAHG) Guidance and
Member State Guidance documents
(e.g. UK Health and Safety Executive –
HSE- Safety Report Assessment Guide –
SRAG- Document)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive (cont.)
 Demonstration
 Not the same depth/details expected for
small/simple processes (e.g. small fuel oil
depot) and highly complicated
establishment (e.g. petroleum refinery)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive (cont.)
 Demonstration vs Proof (art.5. para.2) :
“Member States shall ensure that the operator is
required to prove to the competent authority
referred to in Article 6, at any time, in particular for
the purposes of inspections and controls referred to
in Article 20, that the operator has taken all
necessary measures as specified in this Directive.”
 Proof focused within inspection activities
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Safety Report purpose in Seveso III Directive (cont.)
 art.10 para.1.e : “Providing sufficient information
to the competent authority to enable decisions to be
made regarding the siting of new activities or
developments around existing establishments.”
 Safety Report is a tool for :
o Permit procedures
o Land Use Planning prior to establishment of
an installation
o Land Use Planning in the area of existing
establishments
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard identification (internal)
 Seveso III, Annex II para 2.b : “Identification of
installations and other activities of the
establishment which could present a majoraccident hazard”
 Major Accident Hazard Bureau (MAHR)
Guidance of Safety Report :
o Possible selection of installation via
screening methods
o Reference to index methods or threshold
criteria for hazardous substances or other
suitable methods
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard identification (internal) (cont.)
 No clear methodology on selection of activities
 Screening methods inherently do not take into
account Domino effects
o Very small LPG tank failure could be
neglected as initiating BLEVE in close-by
much bigger tank
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard identification (external)
 Seveso III, Annex II para 2.c : “On the basis of
available information, identification of neighbouring
establishments, as well as sites that fall outside the
scope of this Directive, areas and developments that
could be the source of, or increase the risk or
consequences of a major accident and of domino
effects”
o External Domino
o Identification of potential source for
secondary accidents
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard identification (external) (cont.)
 Available information
o No requirements for risk assessment in
Third Party installations
o Authorities should coordinate information
exchange between installations
o Absence of information in case of out-of
(Seveso Directive) scope neighbours (as no
risk assessment required for them)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hazard identification and locations
 Seveso III Directive, Annex II para 2.d :
“description of areas where a major accident
may occur”
 Same problems as with installation
identification
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected in Hazard
Identification
 Methodology applied
 Areas examined
 Support information related to installation (layout, Process Flow Diagrams –PFDs-, Piping and
Instrument Diagrams –P&IDs, etc.)
 Primary releases along with causes
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Identification of accidents and risk analysis
 Seveso III Directive, Annex II para.4.a : “detailed
description of the possible major-accident scenarios and
their probability or the conditions under which they occur
including a summary of the events which may play a role
in triggering each of these scenarios, ….”
o Possible : on what basis ? Which scenario is
not considered as impossible ? (very low
probability, history ?)
o Possible vs “credible” scenario dilemma
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Identification of accidents and risk analysis (cont.)
 “probability or conditions”… No clear
requirement for probability (either qualitative or
quantitative)
 No requirements for specific hazard
identification/accident selection methods
 Member States guidance define the type of
assessment (including requirements for
probabilities) and implementation details
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Identification of accidents and risk analysis (cont.)
 Seveso III Directive, Annex II para.4.c) : “Review
of past accidents and incidents with the same
substances and processes used, consideration
of lessons learned from these, and explicit
reference to specific measures taken to prevent
such accidents”
o Simple submission of a printout of past
accidents list does not contribute to
establishment safety status
o Lessons learnt expected to had been
applied in establishment
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for scenarios
selection and description
 Methodology applied, including criteria for
selection of accidents to be used in
Consequence Analysis
 Description of scenarios, including :
o duration type (instantaneous, specific
duration, continuous),
o size of release (equivalent “hole”)
o top events expected
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Consequence analysis
 Seveso III Directive, Annex II para.4.b :
“assessment of the extent and severity of the
consequences of identified major accidents
including maps, images or, as appropriate,
equivalent descriptions, showing areas which
are likely to be affected by such accidents
arising from the establishment”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Consequence analysis (cont.)
 Clear statement that accident should arise from
establishment (no interest in consequence from
accidents in neighbour establishments which
could cause Domino effects)
 No requirements for methodologies of
consequence analysis
 No definition of consequence level in interest
(incl. Domino effects)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Consequence analysis (cont.)
 Indirect reference to some consequence levels
related to major accidents in Directive Annex VI
(accident reporting to Commission), as for
example : 1 death, 6 injuries in establishment, 1
injury outside establishment, dwellings (outside
establishment) damaged and unusuable…
 Annex VI should not be straightforward used for
consequence levels definition
 Member States Guidance documents, or
legislation (e.g. France, Italy) define the
consequence end-points to be used
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation (Seveso
III Directive, Annex II)
 para.4.d : “description of technical parameters
and equipment used for the safety of
installation”
 para.5.a : “description of the equipment
installed in the plant to limit the consequences
of major accidents for human health and
environment, including …..”
 para.5.d : “description of any technical and
non-technical measures relevant for the
reduction of the impact of a major accident”
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation
 Measures for safety of installation (safety
barriers) to be considered:
o Control measures
Monitoring equipment (e.g. local/remote
instruments for operating parameters
monitoring)
Process control systems regulating
operating conditions, such as pressure
Emergency Shut Down (ESD) systems
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation (cont.)
 Measures for safety of installation (cont.)
o Prevention measures
Design basis/standards
Active prevention equipment (e.g.
Pressure Relief Valves preventing
equipment failure due to overpressure)
Passive prevention equipment (e.g.
safety dikes)
Procedures (e.g. vessel/tanks inspection
procedures)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation (cont.)
 Measures for safety of installation (cont.)
o Mitigation measures (passive/active), such
as :
fire protection measures/equipment (fire
resistant structures, fire monitors etc.)
oil spill contingency equipment (booms,
absorbent materials etc.)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation (cont.)
 Information expected on :
o Basic parameters and standards for design
o Safety equipment main characteristics (firefight water supplies locations/volumes, firefight pumps capacity, fire-fight network etc.)
o Efficiency of safety measures (e.g. coverage
of areas with hydrants/monitors and fire
houses)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation (cont.)
 Information expected on : (cont.)
o Control and monitor of measures (testing,
inspection frequency)
o Training related to safety measures
 Information not to be provided when not
contributing to report and being available else
where, e.g. hydraulic calculations of pressure
drop in fire-fight network (available anyway in
fire-protection study)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation, Seveso
III Directive Annex II
 para.5.b : “organisation of alert and
intervention”
 Directly related with internal emergence plan :
o Alert equipment and organisation
o Emergency response team organisation and
actions
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation,
Seveso III Directive Annex II (cont.)
 para.5.c : “description of mobilisable
resources, internal or external”
o mobilisable resources : not available
immediately
o internal resources : within establishment
e.g. masks or fire-fighting foam inventory
stored in warehouse
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Accident control, prevention and mitigation,
Seveso III Directive Annex II (cont.)
 para.5.c : (cont.)
o External resources, e.g. collaborating
installations providing, either additional
emergency responders or emergency
response equipment
o Not to be confused with resources provided
by Authorities during activation of External
Emergency Plan
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Risk Assessment Management
 Risk assessment should be applied throughout
the whole lifecycle of an establishment
 Conceptual design
 Basic/Detailed design
 Operation, maintenance, inspection
 Revamps
 Risk assessment should not be a static action
due to submission of Safety Report, but a
continuous process
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Risk Assessment and Safety Management
 Risk assessment is a core element in Safety
Management System (Seveso III Directive
Annex III), as involved in:
o identification and evaluation of major
hazards
o operational control
o management of change
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic approach in EU (Cyprus, Germany,
Greece, Spain etc.)
 Analysis based only to consequence extents
(safety zones defined by consequence endpoints set by Authorities), no probabilities of
accidents used
 Simpler to implement
 Smaller set of scenarios required
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic approach in EU (cont.)
 Safety zones definition example (Greece)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic approach in EU (cont.)
 More conservative (all accidents are treated as
equivalent), worst case scenarios included
 Usually 3 Safety Zones set in-line with Zones for
emergency planning
 Inherently, safety measures not taken into
account in general, no motivation for high
performance safety measures
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic approach in EU (cont.)
 Acceptance criteria set based on vulnerable
objects presence in Zones *, Cyprus example :
*Zones almost identical to Greek zones
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Deterministic Approach
 Description of models used, including :
o assumptions on model parameters (e.g.
atmospheric stability classes, confinement
degree, exposure time) and support on
assumptions validity
 Consequence end-points and harm/damage
relation (zone definition, toxicity data/probit
functions)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Deterministic Approach (cont.)
 Consequence analysis results on :
o Release characteristics (rate, duration,
mass)
o Top event main characteristics (e.g. BLEVE
diameter/duration)
o Effects vs distance tables/graphs, Zone
maps
o Vulnerable object review (if required)
 Risk acceptance results (risk matrix)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic Approach BLEVE results example
(table)
• Thermal radiation level defined by Authorities for
each Zone to be reported
• Similar standard Zones defined for overpressure,
toxics
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic Approach BLEVE results example
(table) (cont.)
 Usually 3 zones defined + Domino Zone
 Standardisation in results presentation
expected
 Clarity to requirements for operators
 Common approach : Zones definition related
also to Emergency Planning purposes
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic Approach BLEVE results example
(graph)
FIREBALL RADIUS 110 m
1500 TDU (250 m) ZONE 1 - VERY SEVERE EFFECTS
10000
THERMAL RADIATION DOSE (TDU)
450 TDU (435 m) ZONE 2 - SEVERE EFFECTS
170 TDU (654 m) ZONE 3 MILD EFFECTS
40 TDU (1109 m) CALCULATION END REQUIREMENT
1000
100
10
0
200
400
600
800
1000
1200
1400
DISTANCE FROM FIREBALL CENTRE, (m)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Deterministic Approach BLEVE results example
(map)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Probabilistic approach in EU (UK, Ireland,
Netherlands, Belgium-Flanders etc.)
• Analysis based on determination of probability
of a specific level of harm
• Acceptance limits usually set for Individual Risk
• Societal Risk usually used as target/guide (not
limit) value
• Usually adopted in countries with high
experienced institutions (HSE in UK, TNO/RIVM
in Netherlands), providing extensive
support/guidance to operators
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Probabilistic approach in EU (cont.)
 Strong dependency on quality of datasets (e.g.
event/failure probabilities database)
 Usually requires large set of scenarios or
screening method
 Specialized software required for efficient
implementation
 Hard for risk communication to the public
 Safety measures performance could be
incorporated, remuneration/motivation for high
performance safety measures
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Probabilistic approach results example (map)
Individual Risk map (contours of annual probability
of 10-6, 10-7 and 10-8, Netherlands)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Probabilistic Approach
 Methodology applied
 Description of datasets for probabilities of :
o initial release (e.g. failure of piping
containing flammable gas),
o intermediate event evolution (e.g. ignition of
flammable cloud)
• Harm/Damage relation with accident effects
(e.g. probit functions for thermal radiation etc.)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Probabilistic Approach (cont.)
 Description of models used (as in deterministic
approach)
 Consequence analysis results on :
o Release and top event characteristics (as in
deterministic approach)
o Effects vs distance tables/graphs (at least
for predefined effect levels used in
Emergency Planning)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Probabilistic Approach (cont.)
 Maps for risk level limits/targets
 Review of vulnerable objects (if included in risk
perception) presence within risk limits/targets
 Societal Risk graphs (if required)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hybrid approach in EU (France, Italy etc.)
 Probability band use, results not so strongly
related to probability value quality
 Sufficient support to operators is provided (e.g.
Italy, France case) for endpoints, probit
functions
 Consequence endpoints set in Guidance
documents or in legislation of Member States
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hybrid approach in EU (cont.)
 Acceptance criteria defined by Risk Matrix using
also severity (number/type of affected
population)
 Closer to Rulebook approach
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hybrid approach in EU (cont.)
 France case (consequence endpoints)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hybrid approach in EU (cont.)
 France case (consequence severity)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hybrid approach in EU (cont.)
 France case (probability classes)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Hybrid approach in EU (cont.)
 France case (risk acceptance matrix for
permits)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Hybrid Approach
 Methodology applied
 Description of datasets for probabilities (as in
probabilistic approach)
 Consequence end-points and harm/damage
relation (zone definition, toxicity data/probit
functions)
 Description of models used (as in deterministic
approach)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Consequence
Analysis in Hybrid Approach (cont.)
 Consequence analysis results on :
o Release and top event characteristics (as in
deterministic approach)
o Probability class results
o Effects vs distance tables/graphs (at least
for predefined effect levels requested)
o Effect maps (for Emergency Planning)
o Review of accidents severity
o Risk Matrix results
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Essential information expected for Domino effects
in all approaches
 Damage levels required for Domino effects
 Secondary accidents expected due to initial
accident (internal primary accident, or known
external accident)
 Comment for accident escalation
 Review if all secondary accidents had been
included in risk assessment in the first place
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Comparison of risk assessment approaches in EU
 No unique methodology in determination of risk
values
 No unique perception of risk, even for same
category of approaches
o probabilistic approach examples :
Netherlands : only “vulnerable” objects
taken into account (hospitals, retirement
homes, schools, non-scattered houses
etc) in limit values
UK : workers and general public
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Comparison of risk assessment approaches in EU
(cont.)
 Diversity in risk limit values used, even for same
approach (lower diversity in deterministic)
o Probabilistic approach examples annual
fatality individual risk limit value :
Netherlands : 10-6
Belgium (Flanders) : 10-5 fence, 10-6
(some residents), 10-7 (vulnerable
objects)
UK : 10-3/10-4 workers/public (if As Low
As Reasonably Practicable - ALARP), 10-6
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Comparison of risk assessment approaches in EU
(cont.)
 Diversity in definition of risk assessment
elements, even for same approach
o Although inherent in probabilistic concept
(as affecting accident frequency related to
Loss of Containment), several protection
measures (e.g. overfill systems) not taken
into account in some countries (e.g.
Netherlands) during probability calculation
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Comparison of risk assessment approaches in EU
(cont.)
 Diversity in risk assessment elements, even for
same approach
o Probabilistic approach :
UK : highly flexible risk assessment
procedure
Netherlands : “locked” risk assessment
procedure described in relevant guidance
(BEVI manual), fixed scenario selection
method (TNO sub-selection method), unique
commercial software to be used (SAFETI)
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Comparison of risk assessment approaches in EU
(cont.)
 Differences in primary data for same approach
from different sources (e.g. failure rates
considered in UK and Netherlands, or probit
function of toxics)
 Diversity in risk assessment for permitting,
Land Use Planning and Emergency Planning
even within one country : UK,: although
probabilistic approach, for LPGs land use
planning, deterministic results used (BLEVE
consequences) 1800 TDU, 1000 TDU, 500 TDU
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Open issues to be solved in each Member State
 Perception of risk (quantitative/qualitative,
individual, societal)
 Risk assessment methodologies to be applied
 Scenarios selection
 Effects severity (lethal, type/levels of injury)
 Safety measures evaluation and link with risk
 Risk acceptance criteria definition and
application
 Environmental Risk
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Literature
 Guidance on the Preparation of a Safety Report to Meet the
Requirements of Seveso Directive 1996/82/EC as Ammended by
Directive 2003/105/EC (Seveso II), Major Hazard Accident Bureau, EU
2005.
 JRC, Implementing Art.12 of the Seveso II Directive: Overview of
Roadmaps for Land-Use Planning In Selected Member States, 2008 .
 CCPS Guidelines for Developing Quantitative Safety Risk Criteria, 2009.
 Checklist System for Safety Reports, Instructions for Preparation and
Inspection of a Safety Report (SR) in accordance with UNECE
Convention on the Transboundary Effects of Industrial Accidents and
the EU Directive 96/82/EC (SEVESO II) by a consistent Checklist
system, Training Session for the Evaluation of Safety Reports 08 - 09
February 2010.
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Literature (cont.)
 Guidelines for Preparation and Inspection of a Safety Report, UNECE
convention on the transboundary effects of industrial accidents & the
EU Directive 96/82/EC (SEVESO ll) by a consistent Checklist system,
2012.
 Sectoral Checklist for Preparation and Inspection of a Safety Report,
UNECE convention on the transboundary effects of industrial accidents
& the EU Directive 96/82/EC (SEVESO ll) by a consistent Checklist
system, 2012.
 An international comparison of four quantitative risk assessment
approaches, RIVM Report 620552001, 2011.
 Safety Report Assessment Guides (SRAGs), Health and Safety
Executive, UK.
 RIVM, Reference Manual Bevi Risk Assessments, 2009.
 Methodology for Evaluation of Safety Reports, Cyprus Ministry of Labour
and Social Security, 2007 (in Greek).
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium
• Literature (cont.)
 National Guidelines for Inspection of Petroleum Products and Natural
Gas Installations, University of Crete, 2004 (in Greek).
 Hazardous Substances Council (AGS), Risk calculations by prescription:
rituals for granting permits and land-use planning, 2010.
 Clive Nussey, Failure frequencies for major failures of high pressure
storage vessels at COMAH sites: A comparison of data used by HSE and
the Netherlands, HSE, December 2006.
This Project is funded
by the European Union
Project implemented by Human
Dynamics Consortium