Management of Environmental Quality: An International JournalHazard and risk evaluation in hydrogen pipelinesH. Dagdougui E. Garbolino O. Paladino R. Sacile

Article information:To cite this document:H. Dagdougui E. Garbolino O. Paladino R. Sacile, (2010),"Hazard and risk evaluation in hydrogenpipelines", Management of Environmental Quality: An International Journal, Vol. 21 Iss 5 pp. 712 - 725Permanent link to this document:http://dx.doi.org/10.1108/14777831011067971

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Hazard and risk evaluation inhydrogen pipelines

H. DagdouguiDepartment of Communication, Computer and System Sciences (DIST),

University of Genova, Genova, Italy andMINES ParisTech, CRC Centre for Research on Risk and Crises, Sophia

Antipolis, France

E. GarbolinoMINES ParisTech, CRC Centre for Research on Risk and Crises,

Sophia Antipolis, France, and

O. Paladino and R. SacileDepartment of Communication, Computer and System Sciences (DIST),

University of Genova, Genova, Italy

Abstract

Purpose The purpose of this paper is the definition and the implementation of a simplifiedmathematical model to estimate the hazard and the risk related to the use of high-pressurizedhydrogen pipeline.

Design/methodology/approach This study aims to investigate the effects of different hydrogenoperations conditions and to tackle with different release or failure scenarios. Based on thecombination of empirical relations and analytical models, this paper sets the basis for suitable modelsfor consequence analysis in terms of estimating fire length and of predicting its thermal radiation. Theresults are compared either with experimental data available in the literature, thus by setting the sameoperations and failure conditions, or with other conventional gaseous fuel currently used.

Findings The findings show that the release rate increasingly varies according to the supplypressure. Regarding the effect of the hole diameter, it hugely affects the amount of hydrogen escapingfrom the leak, up to a value of approximately 0.3 m, after which the release rate remains fixed at amaximum of 43 Kg/s. For failure consequences related to jet flame, the leak dimension has a strengthimpact on the flame length.

Originality/value This paper represents a helpful engineering tool, to establish the safetyrequirements that are related to define adequate safety buffer zones for the hydrogen pipeline in orderto ensure safety to people, as well the environment.

Keywords Hydrogen, Hazards, Risk analysis, Safety

Paper type Research paper

1. IntroductionHydrogen has been often recognized as the likely energy carrier for the future energysystems because it would represent the panacea of the growing concerns inaccordance with fossil-resource depletion, global warming, and increased air pollution.The benefits are motivated by the fact that hydrogen can be manufactured from anumber of primary energy sources, such as natural gas, coal, biomass and water,contributing towards greater energy safety and flexibility (Hugo et al., 2005).Generally, hydrogen is produced, stored, and then transported to the end-users; in

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Received 15 November 2009Revised 10 February 2010Accepted 18 March 2010

Management of EnvironmentalQuality: An International JournalVol. 21 No. 5, 2010pp. 712-725q Emerald Group Publishing Limited1477-7835DOI 10.1108/14777831011067971

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general, it must be transported from production plants to the storage or demand points,so that, the delivery process of its supply chain brings new hazards exposures. Hence, asafe and sustainable transition to the use of hydrogen requires that the safety issuesassociated with the hydrogen have to be investigated and fully understood(Venetsanos et al., 2003). The pathways involved between different supply chainsnodes are realized by a variety of delivery technologies. Among them, the pipeline hasproven to be one of the cheapest ways to transport hydrogen, especially for large areaswith large hydrogen demand (Yang and Ogden, 2007). About 630 miles of transmissionpipelines in the US transport hydrogen today, most of which are located in the GulfCoast region (DOE Pipeline Working Group Workshop, 2005). In addition, pipelinecompressed gas transportation provides an environmental friendly way to satisfydemand, with zero greenhouse gas emissions. However, this infrastructure is oftenexposed to interference from accidents, human errors, abnormal operations,equipments failures, etc. So, it is more important to study the failure case linked tothe hydrogen compressed gas delivery or storage in order to evaluate the danger thathydrogen accidents may cause. As reported by the h2 incidents database, the hydrogenincidents may be due to the equipment failure, human errors, inadequate maintenanceand others (h2 incidents). Figure 1 shows the frequency of occurrence of the maincauses responsible for the hydrogen failure in the delivery infrastructure, among thereported incidents that happen during the delivery, the occurrence of equipment failurehas the higher frequency.

The knowledge of the failure cases represents an important step in the phase of riskevaluation. Modelling the failure of hydrogen storage or transportation devices couldoffer a support for decisions makers to set up suitable safety standards as regards theextent of the hazardous zone and their related risks. In the case of the occurrence of anaccidental leak, the outcomes may lead to fires and/or explosions that may affectviolently people, environment and properties. According to (Houf and Schefer, 2007),these leaks range from small-diameter, slow release leaks from holes in delivery pipesto larger, high-volume releases resulting from accidental break in the tubing fromhigh-pressure storage tanks. The area of hazard associated with the damage to peoplewill depend on the type of pipeline failure, time ignition, land cover and meteorologicalconditions, ambient factors (open space/confined) ( Jo and Ahn, 2006). In addition, the

Figure 1.Histogram of the incidentscauses (equipment failure,

human errors, failure tofollow the standards

operation process (SOP),vehicles collision andothers) in the case of

hydrogen delivery

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way in which an accidental release behaves, depends strongly on the layout, and size ofany hydrogen infrastructure (Tanaka et al., 2007). The lack of adequate maintenance,system monitoring and oversight of maintenance of these facilities can contribute tothe ignition of a fire, which could be difficult to extinguish and represent severe dangerto the fire fighting personnel. British Gas concluded that leaks might propagate tofull-bore rupture if the ratio of opening stress to yield stress of a pipe is greater thanabout 0.3 (Townsend and Fearnehough, 1986). Furthermore, according to the h2incidents database (h2 incidents), about 84 per cent of the hydrogen incidents reportedin the delivery are mainly due to the release of the hydrogen substance from thevehicle, 50 per cent of this percent will ignited once released. In brief, understandinghydrogen behaviour during and after the unintended release is important for thedevelopment of installations protocols and risk mitigation processes.

A wide range of models and approaches have been developed in the literature so topredict the release failure, as well as to assess its consequences. Xua et al. (2009)investigated numerical simulations of sudden direct release of pressurized hydrogeninto air; their study aims to capture the spontaneous ignition of the gas by the use ofcomputational fluid dynamics, and then to visualize the ignition mechanism whenpressurized hydrogen is released directly into an open ambient environment. Ananalytical model has been developed by (Yan-Lei et al., 2009) for diffusion of highpressured hydrogen due to storage tank failure; the authors studied the influence ofseveral important factors on the diffusion of hydrogen such as the wind speed, theambient temperature, the leaking position and others.

Under the framework of this paper, the main aim is to set up a simplifiedmathematical model for a prompt assessment of the flow rate of hydrogen through asudden release from high-pressurized hydrogen pipeline. Basing on the combination ofempirical equations and analytical models, the current paper aims to suggest suitablemodels for consequence analysis in term of estimating fire length and predicting itsthermal radiation. The results are then compared either with experimental dataavailable in the literature, or with other conventional gaseous fuel by setting sameoperations and failure conditions.

2. Hazard modelling2.1 ReleaseThe mass flow rate of hydrogen escaped from a hole is determined according to twoflow conditions, which are chocked and non-choked (Montiel et al., 1998), so, the valueof flow rate at the hole will depend on whether the flow is sonic or subsonic. This willbe established by computing the critical pressure ratio.

In this study, the pressure at which the gas escapes from the hole is supposed to bestrictly higher than the critical pressure. For the case of hydrogen, the value of thiscritical pressure is equal to 1.92 bar. Unlike the release in the hydrogen high-pressuredtank, which mainly depends on the stagnations conditions of the tank, the release rateof high-pressurized hydrogen from a leak in the pipeline depends on the operatingpressure, the pipeline diameter and the length of pipeline from the supply point to thefailure point. Due to large differences between the pipeline and its outside ambient, theflow conditions at the release become critical, so that a sonic flow will release from thefailure point, and then the flow rate of hydrogen can be estimated as:

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QHole Qh2sFc

1

Where Qh2s is the peak initial release rate defined as follow (Crowl and Louvar, 2002):

Qh2s pD2Pl

4

gr0P0

2

g 1 " # g1 = g21 vuut 2

The term in the denominator of the QHole is due to the frictional loss in the pipeline andit is determined using ( Jo and Ahn, 2003):

Fc 1 4l

2f FLR

DP 2=g 1 2= g21

vuut 3Where Fc- is the term responsible for the loss of pressure inside the pipeline, DP m isthe hole diameter, f F - is the fanning friction factor, l- is the dimensionless hole sizewhich is the ratio of the effective hole area to the pipe cross-sectional area, LRm is thedistance from the hydrogen supply point to the failure occurrence, r0[kg/m

3] thestagnation density of hydrogen gas at operating conditions, P0[Pa] is the stagnationpressure of gas at operating conditions and g [-] is the specific heat ratio of gas, that isequal to 1.41 for hydrogen gas.

Due to the length from the hydrogen supply source to the leak point in the pipelinenetwork, the pressure inside the pipe drops according to the condition of the intervalwall pipe. The frictional loss is due completely to the pipe friction, and it will depend onthe pipe length and roughness. According to (Jo and Ahn, 2006), the fanning friction issupposed to be constant over the length of the pipeline, and it is equal underestimatedto a value of 0.0026 for steel pipeline. Several important factors could affect thestrength of the consequences in the case of failure occurrence, for instance:

. pipeline operation conditions (pressure and temperature);

. occurrence of failure at confined or unconfined space;

. meteorological conditions (wind, temperature and humidity); and

. position and dimension of the failure point.

During the current study, it is assumed that the pipeline operates in an unconfinedspace, so, in case of failure, hydrogen will be released in an open space. Moreover, it isworth to mention that in the framework of this study, the meteorological conditionswill not be taken into account and the accidental jet fire scenario will be the oneevaluated in terms of thermal radiation and damage caused. Figure 2 is used to showdifferent accident scenarios that can come from a high-pressurized hydrogen pipeline.During this current study (see Figure 2).

2.2 Jet flame lengthThe geometry of jet fire is an important parameter in the consequence analysis, since itallows the prediction of the safety distance that must be kept in order to minimize theindividual and the environmental risks, and it also constitutes fundamental

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information for hazard analysis. The length of the jet flame is the dominant feature tobe known in order to simulate the possibility of the flame impingement on nearbyfacilities (Bagster and Schubacht, 1996).

As the compressed hydrogen is abruptly released into air, the chocked release isgenerated ahead of the under-expanded jet. The pressure will drop gradually until theambient pressure value. Several studies in the literature have defined manymathematical models to compute the length of the flame, (Delichatsios, 1993) developedan equation based on the non-dimensional Froude number that measures the ratio ofbuoyancy-t-momentum forces in jet flames. In another study, Mogi and Horiguchi(2009) have done experimental investigations, according to the authors, the flamelength is proportional to 0.53 power of the mass flow rate, thus for an operatingpressure up to 0.1 MPa. This equation is valid for the case of high-pressurizedhydrogen tank. So, due to the high operating pressure of pipeline, the second empiricalrelationship developed by Mogi and Horiguchi (2009) will be adopted in this study. Ithas been considered that the pipeline operates as a tank or, in others words; thedimension of the hole is very small comparing to the dimension of the pipe. The flamelength is expressed as:

Lf 20:3Q0:53m 4where Lf m is the length of the flame and Qmkg=s is the mass flow rate of hydrogen.2.3 Thermal effect from jet fireDue to the large pressure ratio between the pipeline and the outside environment atatmospheric pressure, critical conditions occur at the leak. The flow becomes sonic in avery small leak dimension. So, the total energy released into the ambient becomeshigher, inducing then a thermal radiation that can exceed many GW by surface(Wilkening and Baraldi, 2007).

In order to compute the thermal radiation from the jet fire, the flame jet could beidealized as point source heat emitters spread along the flame envelope. The total heatflux reaching a given point is obtained by summing the radiation received from eachpoint source emitter. One simplified assumption that could be incorporated in thecomputation of the thermal radiation is to collapse the set of heat emitters into a singlepoint source emitter, located in the ground level (Quaranta et al., 2002). Even if theimplemented model induces some errors in the heat flux, it is preferred to many others

Figure 2.Diagram of hydrogenaccidental scenarios

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since, first, it avoids the tedious calculation of the heat flux of each axial position of theflame, and second, it incorporates many parameters that can play a paramount role inreal jet fire events, for instance, those responsible for the gas/air combustion (Hc). Thethermal radiation from the flame is inversely proportional to the square of the distance.It can be estimated as suggested in (API RP 521, 1990):

I htaQeff Hc4pr 2

5

Where h- is the combustion efficiency factor ( 0.15 for H2 and 0.2 for CH4), Hc [J/kg]is the heat of combustion ( 141.80MJ/kg for H2 and 55.50MJ/kg for CH4), ta- is theemissivity factor ( 1 for H2 gas and 0.2 for CH4 gas); it is defined as the fraction of thetotal chemical heat release that is radiated to the surroundings, Qeff kg=s is theeffective gas release rate and rm is the radial distance from heat source (flame) to thelocation of interest (see Figure 3).

The effective hydrogen release rate reflects a representative steady-stateapproximation to the actual release rate. It can be approximated using the followingformula:

Qeff CQh2s 6where C is the decay factor, it reflects the tendency at which the released hydrogen flowrate lose its effectiveness, In others words, the decay factor describes the variation inpressure between the atmospheric pressure and the pressure inside the pipe just beforeescaping from the leak. (Hill and Catmur, 1994) quote a value of 0.25 for the decayfactor.

3. Risk evaluationThe combination of hazardous release, and jet flame associated with high-pressurehydrogen pipeline operations, are drastically encountered with higher fatalities. Sincemany decades, different methods have been developed to make a better understandingof the hazard, and then set up efficient models for risks assessment on human life andon the environment. The aim of consequence analysis is to determine the failure case,and then to identify its damage. Hydrogen is a flammable gas, so, the consequence offire is almost present, and may specifically result in damages caused by thermal

Figure 3.System under study

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radiation. Once the gas is escaping from the leak, it is ignited and a jet of flame iscreated in the air; the heat radiated from the flame may be significant. According to theh2 Incidents report, many hydrogen failures in the phase of the delivery affect humanlife, damage the properties in neighbourhood and create others injuries. A statisticalanalysis has been done on the h2 incidents report (h2 incidents) so to evaluate theconsequences of hydrogen failure in the delivery. Results are summarized in Figure 4.It can be depicted that property damages are the one that have the higher percentage(39 per cent).

The consequence modelling consists in simulating the behaviour of the release ofhazardous substances and the impact of such events on receptors (individuals,buildings, and environment). The damage caused by the pipeline failures can bedetermined using the following formula (Gerboni and Salvador, 2009):

Dam DpAV c 7Where Dam: [the number of facilities/event] is the damage, Dp [persons/km

2] is thepopulation density, V c- is the vulnerability coefficient, (it means the number of peoplewho die because of the accident event. According to (Mannan, 2005), the value of thevulnerability is taken equal to 5 per cent), A [m2] is the area in vicinity of the pipelineinvolved in the accident. It is related to the radial distance from the failure point bypr 2.

The quantitative risk evaluation is a crucial phase in studying the feasibilityimplementation of a new infrastructure. So, it answers the questions related to theacceptability by national/regional and local scales authorities. In order to compute thevalue of risk, the frequency of the failure event is estimated to be equal to 5.1026.

Generally, the risk of a specified failure can be summarized in the following formula:

Risk probability adverse consequencesThe probability expresses the frequency of occurrence of the event or of the failure ( jetfire, explosion, flash fire . . .). This information is usually recorded according to the dataaccumulated during the infrastructure operating, so, in order to have the knowledge ofthis information, statistical analysis must be done on the raw data. Whereas, theadverse consequence depicts the damage related to the number of people harmed,goods destruction and others.

4. Results and discussionsNumerical simulations have been carried out so to depict the effect of the dimensionlesshole size on the flow rate of hydrogen released. It is assumed that the length at whichthe failure occurs is 5,00 m far from the hydrogen supply point. Figure 5 shows that therelease rate varies increasingly according to the pressure for different values of l

Figure 4.Pie bars of the damagesand injuries due to thehydrogen failure in thedelivery mode

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ranged between 0.0252 and 0.04. As l increases, this variation tends to have a constantshape for higher values of the dimensionless hole size.

In order to highlight the relationship between the hole diameter and the hydrogenrelease rate so to better understand the results of Figures 5 and 6 has beenintroduced. It appears that the hole diameter from which hydrogen gas is escapedhugely affects the amount of hydrogen released from the leak, up to a value ofapproximately 0.3 m; after which the release rate remains fixed at a maximum of43 Kg/s. The stagnation of the release rate for the higher values of the leak diameter isdue to the fact that the release cannot exceed the maximum rate that can flow in thepipeline. This is in perfect agreement with the method proposed by (Yuhu et al., 2003).

Figure 5.The variation of therelease flow rate of

hydrogen versus thepressure at the supply

point for different valuesof l

Figure 6.Relationship between thehole diameter and release

rate

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Figure 7 shows the trend of the hydrogen flame length as a function of the stagnationpressure at the hydrogen supply point; the curve displays this variation for variousvalues of leaks diameters. The data obtained for the flame length are valid for a valueof operation pressure higher than 0.1 MPa. By analyzing Figure 7, it can be seen thatincreasing the value of the supply pressure does not have a drastic impact on the flamedimension for a small value of the leak diameter. For instance, a value of 10 m for theflame length is observed for a leak diameter of 10 mm, this value of the flame lengthremains constant for different values of the hydrogen pressurized supply point. Thistrend will change gradually as we increase the value of dh. However, enhancing thepressure will in turn increase the value of the flame length, for example, for a leakdiameter equal to 79 mm, the hydrogen flame length can have 50 m for P0 5 MPa toattain a value of 117 m for P0 100 MPa. The observed behavior is due to the fact thatincreasing the diameter of the hole, the hydrogen mass released will increase, inducingthen, a higher jet velocity, which enhances the flame length, but, once the maximumflow rate that can release is reached, this increasing behavior of the flame stops.

Computational results have been also compared with those reported by (Mogi andHoriguchi, 2009). Figure 8 shows this comparison for same values of pressure and leakdiameter. It appears that there is a slightly over-prediction using the flame lengthmodel for the pipeline. For instance, a value of 0.802 m is obtained using the currentmodel, instead of a 0.6 m for experimental data. This difference could be justified bythe fact that the mass flow rate used in the pipeline formulation suppose the pipeline astank, furthermore, it does not take into account the contact between the releasedhydrogen and the outside meteorological conditions.

The characterization of the thermal radiation from the jet flame is a crucial part toassess the consequence of the pipeline failure; also, it constitutes an important task todevelop new safety codes, and to have an exact knowledge on the suitable places wherethe thermal sensors should be placed to detect hydrogen gas releases. In this

Figure 7.The jet flame length asfunction of the pressure atthe supply point

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framework, it is expected that the downstream region from the hydrogen jet flame isparticularly susceptible to thermal hazards. This hazard is shown in term of the thermalradiation or heat flux in Figure 9. It shows the variation of the thermal radiation as afunction of the radial distance (from the centered flame point to the location of interest).For a radial distance, less than approximately 7 m, the values of the thermal radiation ofthe hydrogen gas are higher, than those obtained for the methane gas. For instance, thethermal radiation for hydrogen is equal to 4,761.33 W/m2 versus a value of 2,025 W/m2,for the methane gas, thus for P0 20.7 MPa this is mainly due to the fact of a higher

Figure 8.Comparison of the currentmodel and experiments byT. Mogi and S. Horiguchi

of the jet length

Figure 9.The heat flux from the

hydrogen jet flame as afunction of the radial

distance

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energy content of hydrogen compared with methane. On the other hand, for a radialdistance higher than 7 m, the thermal radiation retains a constant value, either forpressure equal to 207 bar or 0.5 bar. The remark may be due to the dissipation of thethermal radiation faraway from the flame-centered point.

Based on the mathematical analysis of the pipeline network has been done,consequences of failures may be estimated. By determining the hazard linked tomanipulating hydrogen gaseous substance, the decisions makers might take suitablemeasures regarding the safety issues. Hereinafter, the application of quantitative riskanalysis is briefly discussed. Table I depicts that the quantitative value of the damagecaused by the pipeline failure increases with the type of the population living inproximity of the infrastructure. Thus, by characterizing the risk according to thepopulation surrounding the pipeline infrastructure, this will bring importantknowledge about the societal risk acceptance criteria.

5. ConclusionIn this paper, an approach to assess the thermal hazard related to the release ofhydrogen high pressure from a pressurized pipeline has been proposed. The failurecase of hydrogen transmission pipeline can lead to outcomes that can cause seriousdamage in the immediate vicinity of the failure point. However, a good knowledge ofthese dangers and their consequences is intended to implement a safe design ofsystems using hydrogen. In these conditions, it is possible to envisage the developmentof hydrogen as an energy carrier with a low risk level socially acceptable. The modelsettled in this paper aims to estimate the hydrogen flow rate that release from theleakage, the length of the ignited flame gas as well as the thermal radiation. The studyincludes also a risk analysis for damaged areas assessment, thus, taking into accountthe density of the population that lives in the vicinity. In this respect, a promisingfuture development may be included to the overall resulting model as a specific add-onof classical geographic information system software for the assessment of the risk inhydrogen pipeline planning.

The radial distance fromthe failure (m)

Thermalradiation (W/m2)

Damage(fatalities/event)

Large population Dpop 20,000(persons/Km2)

1 159,735 0.0003

6 4,437 0.113016 624 0.803836 124 4.0694

Medium populationDpop 12,000 (persons/Km2)

1 159,735 0.0002

6 4,437 0.006816 624 0.482336 124 2.4417

Low population Dpop 1,500(person/Km2)

1 159,735 0.00024

6 4,437 0.0084816 624 0.0602336 124 0.305

Table I.Thermal radiation anddamages as function ofthe radial distance fromthe failure point, for large;medium and smallpopulation

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Xua, B.P., El Himaa, L., Wena, J.X. and Tamb, V.H.Y. (2009), Numerical study of spontaneousignition of pressurized hydrogen release into air, International Journal of HydrogenEnergy, Vol. 34, pp. 5954-60.

Yan-Lei, L., Jin-Yang, Z., Ping, X., Yong-Zhi, Z., Hai-Yan, B.a., Hong-Gang, C. and Huston, D.(2009), Numerical simulation on the diffusion of hydrogen due to high pressured storagetanks failure, Journal of Loss Prevention in the Process Industries, Vol. 22, pp. 265-70.

Yang, Y. and Ogden, J. (2007), Determining the lowest-cost hydrogen delivery mode,International Journal of Hydrogen Energy, Vol. 32, pp. 268-86.

Yuhu, D., Huilin, G., Jingen, Z. and Yaorong, F. (2003), Mathematical modelling of gas releasethrough holes in pipelines, Chemical Engineering Journal, Vol. 92, pp. 237-41.

Further reading

Jo, Y.D. and Ahn, B.J. (2002), Analysis of hazard areas associated with high-pressure natural gaspipelines, Journal of Loss Prevention in the Process industries, Vol. 15, pp. 179-88.

US Department of Energy (n.d.), Hydrogen Program, H2 Incidents Reporting and LessonsLearned, US Department of Energy, Washington, DC, available at: http://h2incidents.org/

About the authorsH. Dagdougui is a PhD candidate on System Monitoring and Environmental Risk Managementat DIST-Department of System, Computer and Communication at University of Genoa and atMines Paris-Tech in the framework of Convention for International joint Doctorate Supervision.She is specialized in the development of methods and strategies for future hydrogeninfrastructures, also risk assessment for hydrogen manipulation. She is an expert in modellinghydrogen production systems via renewable energy and hydrogen supply demand for refuellingstations. She is author and co-author of three publications on international/national refereedjournals and conference proceedings. Hanane Dagdougui is the corresponding author and can becontacted at: hanane.dagdougui@unige.it

E. Garbolino is a Lecturer and Researcher at the Crisis and Risk Research Centre (CRC),MINES ParisTech (France), and has been since 2002. He holds a Masters degree in Ecology (in1997) at the University of Marseille and a PhD in geography (in 2001) at the University of Nice Sophia Antipolis. His research is mainly dedicated to the definition and the implementation ofspatial decision support systems for private or public decision makers with regard to natural,industrial, and technological risks. He has also published books and papers on risk preventionpolicy and its organization based on the concept of defense in depth, the role of feedbackexperience to promote and improve the safety culture in the organizations, and the definition ofdynamic risk assessment methodologies based on the system dynamics approach.

O. Paladino is an Associate Professor of Chemical Engineering at the University of Genovaand chairperson of the Council for the Environmental Engineering Degree Courses (BSc andMSc) at the University of Genova. She is an expert on identification of industrial and man-madehazards by means of dynamic modelling of reactive chemicals, field data analysis and pollutantsources identification; evaluation of both outdoor and indoor environmental and human healthrisk. She is also an expert on reduction of industrial and man-made hazards by processoptimization, on-line fault diagnosis and control of chemical plants; solid-waste and wastewatermanagement, remediation techniques.

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R. Sacile is an Assistant Professor at the University of Genova, Italy, where, since 2000, hehas held the Professorships of Geographic Information Systems and Models and Methods for theManagement of Environmental Systems. He earned his Italian Laurea in Electronic Engineeringin 1990 from University of Genova, Italy, and his PhD in 1994 from Politecnico of Milan, Italy.Since 2003, he has been responsible for a research contract between Eni group, the mostimportant Italian petrol chemical company, and University of Genova on different aspectsconcerning hazardous material transport. Since 2006, he has been a member of the NATOEnvironmental Security Panel. His main research interests are related to computer based anddecision support methodologies and their integration within an information system, with specificapplications to the environmental and transport fields. His research has appeared in journalssuch as: Decision Support Systems, Energy, Journal of Cleaner Production, EnvironmentalModelling & Software, Resources, Cconservation and Recycling and Waste Management.

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This article has been cited by:

1. P.H.C. Lins, A.T. de Almeida. 2012. Multidimensional risk analysis of hydrogen pipelines. InternationalJournal of Hydrogen Energy 37:18, 13545-13554. [CrossRef]

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