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Reitan, Nina KristineORCID iD iconorcid.org/0000-0002-6436-0393
Publications (10 of 18) Show all publications
Sesseng, C., Reitan, N. K., Storesund, K., Fjellgaard Mikalsen, R. & Hagen, B. (2020). Effect of particle granularity on smoldering fire in wood chips made from wood waste: An experimental study. Fire and Materials
Open this publication in new window or tab >>Effect of particle granularity on smoldering fire in wood chips made from wood waste: An experimental study
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2020 (English)In: Fire and Materials, ISSN 0308-0501, E-ISSN 1099-1018Article in journal (Refereed) Epub ahead of print
Abstract [en]

Fires in wood waste storages cause financial losses, are difficult to extinguish, and emit large amounts of fire effluents. The mechanisms related to fires in wood chip piles are not well elucidated. To find suitable preventive measures for handling such fires in wood waste, a better understanding of the physical properties of wood waste is needed. The present study investigates how granularity affects mechanisms of smoldering fire and transition to flaming in wood chip piles. Eighteen experiments with samples inside a top-ventilated, vertical cylinder were conducted. Heating from underneath the cylinder induced auto-ignition and smoldering fire, and temperatures and mass loss of the sample were measured. The results showed that granularity significantly affects the smoldering fire dynamics. Material containing larger wood chips (length 4-100 mm) demonstrated more irregular temperature development, higher temperatures, faster combustion, and higher mass losses than material of smaller wood chips (length <4 mm). The larger wood chips also underwent transition to flaming fires. Flaming fires were not observed for small wood chips, which instead demonstrated prolonged and steady smoldering propagation. The differences are assumed to be partly due to the different bulk densities of the samples of large and small wood chips affecting the ventilation conditions. Increased knowledge about these combustion processes and transition to flaming is vital to develop risk-reducing measures when storing wood chips made from wood waste in piles.

Place, publisher, year, edition, pages
John Wiley and Sons Ltd, 2020
Keywords
fire, granularity, smoldering, transition to flaming, waste, wood chips
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-44454 (URN)10.1002/fam.2812 (DOI)2-s2.0-85080871260 (Scopus ID)
Available from: 2020-03-17 Created: 2020-03-17 Last updated: 2020-03-17Bibliographically approved
Fjellgaard Mikalsen, R., Durgun, Ö., Williams Portal, N., Orosz, K., Honfi, D. & Reitan, N. K. (2020). Efficient emergency responses to vehicle collision, earthquake, snowfall, and flooding on highways and bridges: A review. Journal of Emergency Management, 18(1), 51-72
Open this publication in new window or tab >>Efficient emergency responses to vehicle collision, earthquake, snowfall, and flooding on highways and bridges: A review
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2020 (English)In: Journal of Emergency Management, ISSN 1543-5865, Vol. 18, no 1, p. 51-72Article in journal (Refereed) Published
Abstract [en]

This review article analyzes factors affecting emergency response to hazardous events on highways and their bridges, with focus on man-made and natural scenarios: heavy vehicle collision with a bridge, earthquake, heavy snowfall, and flooding. For each disaster scenario, selected historical events were compiled to determine influential factors and success criteria for efficient emergency response, both related to organizational and technical measures. This study constituted a part of a resilience management process, recently developed and demonstrated within the European Union (EU)-funded H2020 project IMPROVER and can be a useful approach in aiding operators of transportation infrastructure to improve their resilience to emergency incidents.

Place, publisher, year, edition, pages
NLM (Medline), 2020
Keywords
article, earthquake, European Union, flooding, highway, human
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-43969 (URN)10.5055/jem.2020.0450 (DOI)2-s2.0-85079106935 (Scopus ID)
Available from: 2020-02-17 Created: 2020-02-17 Last updated: 2020-02-17Bibliographically approved
Reitan, N. K., Friquin, K. & Fjellgaard Mikalsen, R. (2019). Brannsikkerhet ved bruk av krysslaminert massivtre i bygninger – en litteraturstudie.
Open this publication in new window or tab >>Brannsikkerhet ved bruk av krysslaminert massivtre i bygninger – en litteraturstudie
2019 (Norwegian)Report (Other academic)
Abstract [en]

This literature study presents recent research on fire safety in cross laminated timber (CLT) buildings. Results from large fire experiments and other studies in the period 2010 - 2018 are summarized, with focus on the following research questions:• How do constructions consisting of protected or exposed CLT contribute to the fire development in a room?• How can contribution to the fire development from detailing of CLT be avoided?There is an increasing desire to use wooden structures in tall buildings, as a substitute for more traditional construction materials. However, the use of combustible construc-tions in buildings in Norwegian Fire Class 3 (usually five floors or more) is not pre-accepted in the guideline to Regulations on technical requirements for construction works (TEK17), and fire safety must therefore be documented by analysis in such structures. When designing tall and complex timber buildings, it must be taken into account that a fire involving a timber construction may have more severe consequences than in buildings with constructions of steel or concrete, if the fire design of the construction and detail solutions is insufficient. Several studies show that fire exposed CLT, or CLT with insufficient protection, can cause a fire to develop faster, be more intense and last longer than a fire where the only fuel is the furniture and fixtures in the fire room. It is shown that the amount of fire exposed timber in a room may have impact on the extent and duration of a fire, but the knowledge has not yet been sufficient enough to be used in fire modeling, design and analysis.Research on charring rates, delamination and auto-extinction, all of which are factors that can have major impact on fire development and the fire resistance of the construction, takes place in Europe, Australia and North America. Although extensive research has been carried out, it is based on few large fire experiments, and the literature is still pointing to several knowledge gaps. However, the research projects have increased the knowledge of fire in timber buildings, and have contributed to the design of detail solutions, guidelines and development of models for function-based design. Revision of EN 1995-1-2 is under preparation and expected to apply from 2022. A knowledge base for the audit can be found in the network COST Action FP1404 Fire Safety Use of Bio-Based Building Products (COST FP1404) Working Group 2 (WG2). They have published several guidelines relevant for the fire design of CLT, including e.g. calculation methods for the prediction of charring rates and depths, determination of reduced CLT cross-section, design of CLT detailing and a suggested test method for evaluating adhesive performance.Based on the literature review, the following conclusions and recommendations are given for CLT constructions:• The design phase must sufficiently consider protection of the construction and con-tribution of the construction to the fire energy, and to a greater extent include the assessment of detailing and ventilation conditions. It should be considered whether analytic fire engineering design also should be required for buildings in the Norwegian Fire Classes 1 and 2 where more than one CLT wall is exposed.• By protecting all CLT surfaces of the structure with cladding, the construction may retain the stability and the load bearing capacity during the required time of fire resistance.• In buildings with only one exposed CLT wall in each fire cell, it may also be appropriate to use solutions that satisfy the pre-accepted performances, but one must consider whether a somewhat longer and more intense heat radiation and flame exposure on the facade outside window openings will require measures beyond the pre-accepted performances given in the guideline to TEK17.• Rooms where two or more CLT walls in addition to the ceiling are exposed, are configurations that should be avoided.• The risk of delamination can be reduced by using heat-resistant glue.• There is generally a need for relevant documentation for fire-resistant solutions for joints between CLT walls and floors and service penetrations in CLT constructions.• Test methods for testing of joints and penetrations in CLT constructions should be standardized. For example, there exists no standardized test for corner joints. Tests of penetration seals for CLT constructions are scarce, although they can be tested according to EN 1366-3. However, CLT is not a standard supporting construction according to EN 1366-3, and this must be taken into consideration when the test results are evaluated. Joints in glulam constructions should also be tested because they are often used in conjunction with CLT elements.

Publisher
p. 88
Series
RISE Rapport ; 2019:09
Keywords
Cross laminated timber; CLT; fire safety; exposed CLT; auto-extinction; charring; delamination; detailing
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-38191 (URN)978-91-88907-36-3 (ISBN)
Note

Prosjektnummer: 20385 Kvalitetssikring: Anne Steen-Hansen Finansiert av: Direktoratet for samfunnssikkerhet og beredskap og Direktoratet for byggkvalitet

Available from: 2019-03-21 Created: 2019-03-21 Last updated: 2020-04-20Bibliographically approved
Sæter Bøe, A. & Reitan, N. K. (2018). Brannsikkerhet og alternative energibærere: Hydrogenkjøretøy i parkeringskjellere.
Open this publication in new window or tab >>Brannsikkerhet og alternative energibærere: Hydrogenkjøretøy i parkeringskjellere
2018 (Norwegian)Report (Other academic)
Abstract [no]

I denne litteraturstudien har vi undersøkt hvordan norske parkeringskjellere er bygget, og hvilke sikringstiltak som finnes mot brann og eksplosjon. Vi har videre sett på mulige konsekvenser for bygg og mennesker ved hydrogengasseksplosjon, der hydrogen fra en lekkasje akkumuleres og antennes, og ved hydrogentankeksplosjon, der hydrogentanken revner som følge av varmepåkjenning.

Hittil er det få gassbiler på norske veier, og det har i liten grad vært vurdert å sikre parkerings-kjellere mot gasslekkasjer og en eventuell eksplosjon. Vanlige sikringstiltak for å redusere risikoen ved en eksplosjon, som store avlastningsflater, deteksjon koblet opp mot ventilasjonsanlegg med tilstrekkelig kapasitet, og eksplosjonssikkert, elektrisk utstyr er derfor lite utbredt i eksisterende parkeringskjellere.

Små lekkasjerater fra et hydrogensystem (slanger, koblinger) i store romvolum med eksos-ventilasjon er ikke forventet å resultere i store overtrykk. For større utslipp av hydrogen, der hele tankens innhold slipper ut på kort tid, er det imidlertid fare for omfattende skader. Forsøk som er beskrevet i litteraturen viser at avhengig av parametere, kan 5 kg hydrogen føre til overtrykk i størrelsesorden 10 – 100 kPa. Forsøkene er imidlertid utført i innelukkede rom med et romvolum mindre enn i en parkeringskjeller, og resultatene må derfor benyttes med en viss varsomhet. En hydrogentank som revner ved eksponering av brann vil føre til en kraftig flammeball, og store eksplosjonsskader lokalt.

Å beregne sannsynlighet for at ulike scenarier skal inntreffe har ikke vært en del av dette prosjektet. Siden flere mindre sannsynlige hendelser må inntreffe samtidig, er sannsynligheten liten for at store lekkasjer fra tanken skal skje når bilen er parkert i en parkeringskjeller, eller at tanken eksploderer ved eksponering for en brann.

Publisher
p. 44
Series
RISE Rapport ; A18 20319:1
National Category
Engineering and Technology
Identifiers
urn:nbn:se:ri:diva-44735 (URN)
Available from: 2020-04-16 Created: 2020-04-16 Last updated: 2020-04-16
Rosenqvist, H., Reitan, N. K., Petersen, L. & Lange, D. (2018). ISRA: IMPROVER societal resilience analysis for critical infrastructure. In: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018: . Paper presented at 28th International European Safety and Reliability Conference, ESREL 2018, 17 June 2018 through 21 June 2018 (pp. 1211-1220).
Open this publication in new window or tab >>ISRA: IMPROVER societal resilience analysis for critical infrastructure
2018 (English)In: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018, 2018, p. 1211-1220Conference paper, Published paper (Refereed)
Abstract [en]

Resilience of Critical Infrastructure (CI) has been a research focus for several years now, with efforts being made to develop methods for the analysis and assessment of CI resilience. However, these efforts are often carried out without consideration of enriching societal risk or resilience assessments with knowledge of the resilience of CI. Bearing in mind that the definition of CI according to the EU reflects the fact that it exists to deliver vital societal functions, the consideration of its resilience in isolation of the community it serves is only addressing part of the problem. The Horizon 2020 project IMPROVER has already developed methodologies for assessing and managing CI resilience. This paper proposes an evolution of the management framework for CI resilience which enriches societal resilience assessment with knowledge of the CI resilience. The framework and societal resilience analysis methodology are both described along with an application of the analysis method.

Keywords
Public works, Reliability, Safety engineering, Analysis method, Horizon 2020, Management frameworks, Research focus, Societal functions, Societal risks, Critical infrastructures
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-36677 (URN)2-s2.0-85058135618 (Scopus ID)9780815386827 (ISBN)
Conference
28th International European Safety and Reliability Conference, ESREL 2018, 17 June 2018 through 21 June 2018
Available from: 2018-12-21 Created: 2018-12-21 Last updated: 2019-06-27Bibliographically approved
Storesund, K., Reitan, N. K., Sjöström, J., Rød, B., Guay, F., Almeida, R. & Theocharidou, M. (2018). Novel methodologies for analysing critical infrastructure resilience. In: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018: . Paper presented at 28th International European Safety and Reliability Conference, ESREL 2018, 17 June 2018 through 21 June 2018 (pp. 1221-1230).
Open this publication in new window or tab >>Novel methodologies for analysing critical infrastructure resilience
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2018 (English)In: Safety and Reliability - Safe Societies in a Changing World - Proceedings of the 28th International European Safety and Reliability Conference, ESREL 2018, 2018, p. 1221-1230Conference paper, Published paper (Refereed)
Abstract [en]

In the field of Critical Infrastructures (CI), both policy and research focus has shifted from protection to resilience. The IMPROVER project has developed a CI resilience management framework (ICI-REF), applicable to all types of CI and resilience domains (technological, organisational and societal) allowing operators to understand and improve their resilience. IMPROVER has also developed methodologies to be used within the framework, accompanied with resilience indicators for operators to assess their technological and organisational resilience. The framework allows CI operators to incorporate resilience management as part of their risk management processes. The ICI-REF, the resilience analysis methodologies and indicators have been optimised, applied and demonstrated in a pilot implementation, focusing on the potable water supply in Barreiro, Portugal. Conclusions from the operators so far are that the indicators, well-defined and unambiguously described, are crucial for monitoring resilience activities, to ensure objective, consistent, repeatable and representative results from the assessed processes.

Keywords
Potable water, Public works, Reliability, Risk management, Safety engineering, Water supply, Infrastructure resiliences, Management frameworks, Novel methodology, Organisational, Pilot implementation, Portugal, Research focus, Risk management process, Critical infrastructures
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-36682 (URN)2-s2.0-85058106056 (Scopus ID)9780815386827 (ISBN)
Conference
28th International European Safety and Reliability Conference, ESREL 2018, 17 June 2018 through 21 June 2018
Available from: 2018-12-21 Created: 2018-12-21 Last updated: 2018-12-21Bibliographically approved
Rød, B., Pursiainen, C., Reitan, N. K., Storesund, K., Lange, D. & Mira da Silva, M. (2017). Evaluation of resilience assessment methodologies. In: Safety and Reliability - Theory and Applications - Proceedings of the 27th European Safety and Reliability Conference, ESREL 2017: . Paper presented at 27th European Safety and Reliability Conference, ESREL 2017, 18 June 2017 through 22 June 2017 (pp. 1039-1052). CRC Press/Balkema
Open this publication in new window or tab >>Evaluation of resilience assessment methodologies
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2017 (English)In: Safety and Reliability - Theory and Applications - Proceedings of the 27th European Safety and Reliability Conference, ESREL 2017, CRC Press/Balkema , 2017, p. 1039-1052Conference paper, Published paper (Refereed)
Abstract [en]

There are a wide range of different frameworks and methodologies for analysing Critical Infrastructure (CI) resilience, covering organisational, technological and social resilience. However, there is a lack of a clear methodology combining these three resilience domains into one framework. The final goal of the ongoing EU-project IMPROVER, ‘Improved risk evaluation and implementation of resilience concepts to Critical Infrastructure,’ is to develop one single improved and easy-to-use critical infrastructure resilience analysis tool which will be applicable within all resilience domains and to all types of critical infrastructure. This article presents part of this work, in which IMPROVER comprehensively evaluated, by demonstration and comparison, a selection of existing resilience methodologies in order to integrate their best features into the new methodology. The selected methodologies were The Benchmark Resilience Tool (BRT) (Lee et al., 2013), Guidelines for Critical Infrastructures Resilience Evaluation (CIRE) (Bertocchi et al., 2016) and the Critical Infrastructure Resilience Index (CIRI). The latter was developed within the consortium (Pursiainen et al., 2017). The results show that it is hard to evaluate and compare the different methodologies considering that the methodologies are not aiming to achieve the same thing. However, this evaluation shows that all the methodologies have pros and cons, and that the IMPROVER project should aim at combining, in so far as is possible and commensurable, the identified pros while avoiding the identified cons into a Critical Infrastructure resilience assessment framework compatible with the current guidelines for risk assessment in the Member States. © 2017 Taylor & Francis Group, London.

Place, publisher, year, edition, pages
CRC Press/Balkema, 2017
Keywords
Public works, Reliability theory, Risk assessment, Safety engineering, Analysis tools, Assessment methodologies, Eu projects, Infrastructure resiliences, Organisational, Risk evaluation, Critical infrastructures
National Category
Engineering and Technology
Identifiers
urn:nbn:se:ri:diva-38101 (URN)10.1201/9781315210469-133 (DOI)2-s2.0-85058128990 (Scopus ID)9781138629370 (ISBN)
Conference
27th European Safety and Reliability Conference, ESREL 2017, 18 June 2017 through 22 June 2017
Available from: 2019-03-08 Created: 2019-03-08 Last updated: 2019-06-27Bibliographically approved
Lange, D., Honfi, D., Theocharidou, M., Giannopoulos, G., Reitan, N. K. & Storesund, K. (2017). Incorporation of resilience assessment in critical infrastructure risk assessment frameworks. In: Safety and Reliability - Theory and Applications - Proceedings of the 27th European Safety and Reliability Conference, ESREL 2017: . Paper presented at 27th European Safety and Reliability Conference, ESREL 2017, 18 June 2017 through 22 June 2017 (pp. 1031-1038). CRC Press/Balkema
Open this publication in new window or tab >>Incorporation of resilience assessment in critical infrastructure risk assessment frameworks
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2017 (English)In: Safety and Reliability - Theory and Applications - Proceedings of the 27th European Safety and Reliability Conference, ESREL 2017, CRC Press/Balkema , 2017, p. 1031-1038Conference paper, Published paper (Refereed)
Abstract [en]

This paper explores the concept of Critical Infrastructure (CI) resilience and its relationship with current Risk Assessment (RA) processes. It proposes a framework for resilience assessment of CI, which integrates the resilience paradigm into the RA process according to ISO 31000. The framework consists of three levels, namely (a) asset (focus on individual CI assets), (b) system (focus on dependencies between CI assets) and (c) national or regional (focus on societal aspects). It is applicable to individual CI or their combinations, accounting both for existing RA processes, for interdependencies and their effect on interconnected CI, while at the same time employing current, available resilience analysis tools and methodologies. This approach is also compatible with the current European guidelines for national RA applied by the EU Member States. © 2017 Taylor & Francis Group, London.

Place, publisher, year, edition, pages
CRC Press/Balkema, 2017
Keywords
Critical infrastructures, Public works, Reliability theory, Safety engineering, Analysis tools, Risk assessment framework, Risk assessment
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:ri:diva-38114 (URN)10.1201/9781315210469-132 (DOI)2-s2.0-85061395869 (Scopus ID)9781138629370 (ISBN)
Conference
27th European Safety and Reliability Conference, ESREL 2017, 18 June 2017 through 22 June 2017
Available from: 2019-03-08 Created: 2019-03-08 Last updated: 2019-06-27Bibliographically approved
Reitan, N. K., Bouffier, C., Durgun, Ö., Guay, F., Ioannou, I., Mira da Silva, M., . . . Vigh, L. G. (2017). Infrastructures facing disaster risk: Pilot implementation of a new resilience management framework. In: : . Paper presented at World Bosai Forum 25. – 28. november 2017, Sendai, Japan.
Open this publication in new window or tab >>Infrastructures facing disaster risk: Pilot implementation of a new resilience management framework
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2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:ri:diva-37571 (URN)
Conference
World Bosai Forum 25. – 28. november 2017, Sendai, Japan
Available from: 2019-01-24 Created: 2019-01-24 Last updated: 2019-06-20Bibliographically approved
Guay, F., Bouffier, C., Lange, D., Mira da Silva, M., Petersen, L., Reitan, N. K., . . . Theocharidou, M. (2017). Supporting disaster risk reduction through better critical infrastructure resilience. In: : . Paper presented at 1st World Bosai Forum 2017 / International Disaster and Risk Conference 2017 (IDRC 2017), November 25-28, 2017, Sendai, Japan. , Article ID P54.
Open this publication in new window or tab >>Supporting disaster risk reduction through better critical infrastructure resilience
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2017 (English)Conference paper, Poster (with or without abstract) (Other academic)
National Category
Natural Sciences
Identifiers
urn:nbn:se:ri:diva-39349 (URN)
Conference
1st World Bosai Forum 2017 / International Disaster and Risk Conference 2017 (IDRC 2017), November 25-28, 2017, Sendai, Japan
Funder
EU, Horizon 2020, 653390
Available from: 2019-07-08 Created: 2019-07-08 Last updated: 2019-08-12Bibliographically approved
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-6436-0393

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