It is our pleasure to hand over to you this book of abstracts for the Nordic Fire & SafetyDays 2019 organized by RISE Research Institutes of Sweden in collaboration Technical University of Denmark, Norwegian University of Science and Technology, Lund University, Aalto University, Luleå University, University of Stavanger, Western Norway University of Applied Sciences and Iceland University as well as VTT Technical Research Centre of Finland Ltd and Danish Institute of Fire and Security Technology.We are very proud to present the abstracts of 63 Nordic and international contributions in the present book of abstracts. The work demonstrates a significant scientific depth and societal relevance. The conference is a response to the extensive interest in the areas of fire and safety engineering in the Nordic countries in the past decades. As the programme and the abstracts show, the NFSD follow up on challenges with respect to safety dealing with aspects of fire and human behaviour as well as rescue service and risk management.

Anne S. Dederichs, RISE Research Institutes of SwedenConference chair

Data intense defined software is becoming more and more prevalent, especially with the advent of machine learning and artificial intelligence. With data intense systems comes both challenges – to continue to collect and maintain quality – and opportunities – open innovation by sharing with others.

To understand challenges and opportunities with ODC, we ran 5 focus groups (4 in Lund and 1 in Kista) with companies and public organizations. We had 27 participants from 22 organizations.

Despite an interest to participate and understanding of the potentials of the subject, the overall maturity is low and ODC is rare. For ODC to be successful, there is a need to study technical, organizational, business, and legal aspects further.

Several large wildfires in Sweden are caused by forestry machinery in operation, but there is no overview or characterization of machine-caused fires. Combining dispatch data, weather, fire danger and interviews with forestry entrepreneurs we gain a deeper understanding of spatial/temporal/weather distributions of these fires as well as their characteristics and underlying mechanisms. The average annual number of machine-caused ignitions in Sweden is estimated to 330-480 (2.0±0.4 ignitions per 1000 ha clear-felled land) of which 34.5 lead to fire-fighter dispatch. These constitute 2.2% of all forest fires and 40% of area burnt. Soil scarification causes most ignitions and the main mechanism is likely high-inertia contact between discs and large stones, causing sparks igniting dry humus/moss. This counters reports suggesting that such metal fragments cannot fulfil ignition requirements. We found a strong spatial relationship between forestry machinery ignitions and the abundance of large stones, represented by a boulder-index generated from 13500 nation-wide site inventories. Further, 75% of the dispatches occurred on days with relative humidity <45%, Duff Moisture Code >26 and Fire Weather Index >12. 75% of the total area burned when Fire Weather Index >20. Cancelling operations in stony terrain during high-risk weather situations can largely avoid the problem.

In 2016 138 000 tonnes of new clothes and household textiles were put on the Swedishmarket (Statistics Sweden, 2017). The production of textile products causes significantenvironmental impacts. Business models engaged in reuse, collective use and prolongedlife-time of textiles therefore have a potential to contribute to reduced total textileconsumption and, as a consequence, reduced environmental impacts from textileproduction.Preceding work in Mistra Future Fashion (Watson et al, 2017) identified ten differentsupporting policy instruments for business models that extend active lifetimes ofgarments. The objective of this report is to select three of the previously identified policyinstruments and estimate the economic, environmental, social effects of these. The threepolicy instruments selected for further assessment were:- A wage subsidy earmarked for businesses that extend the active lifetime of textiles- A knowledge hub assisting businesses start up or transition to more circular models- Start-up/transition fund for business models/initiatives that extend the activelifetime of textiles.

In recent years there has been a growing interest for building lightweight multistorey woodenresidential buildings in countries like Sweden with large and renewable forests. While positive aspectsof these buildings, such as sustainability, ease of construction and lightness, motivate building more inwood, poor acoustic performance is a risk which concerns the wooden-building industry.Low-frequency impact sound from walking of the neighbors upstairs is the main source of complaintsabout the acoustic performance of these buildings. The disturbance caused by walking sounds,transmitted through lightweight wooden floors, results in acoustic discomfort and impairs theperceived quality of the building; sometimes even when the building has fulfilled an acoustic classhigher than minimum requirement, according to the national standard on sound classification and itssingle number ratings. The standard methods for objective evaluation of impact sound insulation offloors cannot predict, at a satisfactory level, the walking sound annoyance that the inhabitants ofwooden buildings experience. This causes an uncertainty about the resulting perceived quality of thesebuildings, which greatly concerns the building manufacturers and demotivates them from choosinglightweight wooden elements over heavyweight building materials such as concrete. This uncertaintycan be overcome by evaluating the perceived acoustic quality of the building prior to its construction.

One solution is to build test houses where the subjective acoustic performance of floor samples can beevaluated in advance to the building construction. However, building a test house is expensive;besides, for evaluating the effect of every design modification on the experienced acoustic comfort ofthe building, a real floor sample has to be built and installed in the house, which would be timeconsumingand costly. An alternative solution is to use virtual acoustic test facilities.In this thesis a virtual design studio for impact sound is developed. It is a tool that facilitates creatingand listening to the acoustic field generated by impact forces such as footsteps on lightweight floors. Italso provides the possibility to evaluate the acoustic performance of floor elements in an early designphase, and to investigate the correlation between design parameters and the perceived impact soundinsulation of the floor. The tool is demonstrated and a very first listening test shows that one can obtainresults which are in good agreement with the results in literature. Loudness, reverberation andthumping are shown to influence the annoyance. It is also shown that there is a difference in judgementof walking sounds by persons who have experience with lightweight floors at home and by those whodo not have that experience.

In this paper, we investigate how different viewingpositions affect a user’s Quality of Experience (QoE) and performancein an immersive telepresence system. A QoE experimenthas been conducted with 27 participants to assess the generalsubjective experience and the performance of remotely operatinga toy excavator. Two view positions have been tested, an overheadand a ground-level view, respectively, which encourage relianceon stereoscopic depth cues to different extents for accurate operation.Results demonstrate a significant difference between groundand overhead views: the ground view increased the perceiveddifficulty of the task, whereas the overhead view increased theperceived accomplishment as well as the objective performanceof the task. The perceived helpfulness of the overhead view wasalso significant according to the participants.

The assessment of perceived quality based on psychophysiological methods recently gained attraction as it potentiallyovercomes certain flaws of psychophysical approaches. Although studies report promising results, it is not possible toarrive at decisive and comparable conclusions that recommend the use of one or another method for a specific applicationor research question. The video quality expert group started a project on psychophysiological quality assessment to studythese novel approaches and to develop a test plan that enables more systematic research. This test plan comprises of a specificallydesigned set of quality annotated video sequences, suggestions for psychophysiological methods to be studied inquality assessment, and recommendations for the documentation and publications of test results. The test plan is presentedin this article.