No description available.

Simulating fire propagation in games can be problematic since it requires immense computational power if the fire is portrayed physically accurate. To decrease the computational power required, simplifications and approximations must be made. The aim of this thesis is to evaluate possible methods for simulating fire spread in a networked game environment. More specifically, a level set and a node graph method are implemented and investigated. A vector field was created with the different level properties, which the two methods used as a base for the fire behavior. The performance and overall behavior of the methods were evaluated and tested in order to create an optimized simulation suited for games. Two implementations were made in the Frostbite game engine. The level set propagates the fire with two different level set operators; the normal advection operator and the vector field operator. The normal advection operator spreads the fire outwards in the normal direction. The vector field operator spreads the fire front according to the vector field. The node graph implementation uses a semi-connected bi-directed graph with nodes as starting positions for the fire. The fire spreads through the nodes via their connections. This implementation also depends on the vector field which was translated to the nodes through scalar projection. The vector field represents the properties of fire dynamics and can be adjusted to move the level set and node graph implementation according to wind, slope and fuel. The node graph implementation was further developed with networked capabilities, a heat grid which translates the heat of the node graph making it possible to sample the heat at a position within the level, and also basic interaction with vegetation. / <p>Examensarbetet är utfört vid Institutionen för teknik och naturvetenskap (ITN) vid Tekniska fakulteten, Linköpings universitet</p>

Purpose: The purpose of the degree project was to investigating fire protection work during construction at various companies and proposing improvement proposals to reduce the risk of fire at construction sites. Method: The method on which the thesis project was based on was a literature study, interviews and document analysis. The literature study has been carried out to gain in-depth knowledge regarding the fire protection during the construction phase. The interview study was conducted at different construction companies to get an idea of ​​how the different companies handle fire safety at construction sites. The document analysis has been carried out with the help of various companies requirements documents, which form the basis for the fire protection work at the construction sites. Results: The results present the companies fire protection work during construction. Prior to the start of construction, a fire protection description is projected that covers how to build to prevent fire safety, it also covers the how parts of the workplace should be designed. The fire protection that proved to exist mostly consists of two mutually independent escape routes with clearly visible escape signs, a dedicated collection point and strategically placed hand-held fire extinguishers that should be within a range of 25 meters. Hot work, electrical causes and arson have emerged as a recurring shortage and cause of most fires occurring at construction sites. There is room for improvement by, among other things, spending more time in planning, introducing a practice on fire and evacuation alarms and creating the company's fire protection description in connection with the production of the A-drawings. Conclusions: In conclusion, there are opportunities for improvement, but unfortunately nothing has been implemented in practice.

No description available.

Environmental issues and the housing shortage is an ongoing debate among politicians. Wood is a building material that Sweden has plenty of and it is a material that, according to research, does not contribute to as much carbon dioxide emissions during production, compared to other construction materials such as concrete and steel. Therefore the demand for timber, in both facade claddings and external wall constructions, is increasing. In light of this, the purpose with this degree project is to study different fire protection methods for wood and compare it to untreated wood. Collecting the facts and information for this degree project at Mälardalens University, is done through literature studies, surveys, and two experiments conducted on two selected fire retardants. The experiments were conducted to test untreated, fire protection impregnated and wood with fire proof paint. One of the experiments tested the load-carrying capacity of the beams after being charred with a gas burner. The other experiment investigated the surface layer and measured the fire spread rate and both experiments tested the fire resistance. The experiments that were conducted concluded that out of the three different methods for facades and beams, fire protection impregnation was the best choice in all five chosen categories: load-carrying capacity, fire resistance, surfaces, environmental impact and health safety for workers. / Miljöfrågan och bostadsbristen är två pågående debatter bland politikerna. Ett byggmaterial som både är miljövänligt och lätt att bygga med är trä. Det är ett byggmaterial som Sverige har gott om och enligt forskning bidrar det inte med lika mycket koldioxidutsläpp vid produktionen jämfört med andra konstruktionsmaterial som betong och stål. Enligt äldre bygglagstiftningar var det enbart tillåtet att bygga hus med två våningar i trä. Det var godkänt att bygga hus med tre våningar om den nedersta våningen bestod utav sten och de två översta i trä. Den nya bygglagstiftningen har inga begränsningar på att använda trä i ytterväggar, oberoende av byggnadsklass så länge de uppfyller funktionskraven. Byggsektorn har varit medveten om att de fick bygga flervåningshus i trä men inte hur det skulle utföras och samtidigt uppfylla bygglagstiftningens krav. Resultatet av ändringarna i bygglagstiftningen, Boverkets byggregler, ökade efterfrågan och utbudet på brandskyddsmedel till trä. De vanligaste produkterna som finns ute för konsumenten är brandskyddsfärg och brandskyddsimpregnering. Trä kan genom brandskyddsimpregnering eller brandskyddsfärg få en brandteknisk klass enligt det europeiska systemet, EN 13501-1, upp mot B-s1,d0 som är högre än för obehandlat trä, Ds1, d0. Tekniskt sett går det att bygga Br1-byggnader med obehandlat trä, dock så krävs det ett antal åtgärder för att uppfylla Boverkets byggreglers funktionskrav, till exempel att installera automatiska släcksystem eller enbart ha trä på en begränsad del av fasaden. Med brandskyddsbehandling går det idag endast att uppnå brandteknisk ytskiktsklass B-s1,d0, vilket inte är tillräckligt enligt Boverkets byggregler som kräver lägst obrännbara fasadbeklädnader i ytskiktsklass A2-s1,d0 för att uppfylla allmänna råden. Fasadbeklädnader av trä, oavsett brandteknisk klass, kan testas med provmetoden SP FIRE 105 och därmed uppfylla föreskriftens krav på ytterväggskonstruktioner med avseende på brandspridning längs fasadytan. Syftet med arbetet är att jämföra olika brandskyddsmetoder av trä och undersöka vilken eller vilka som är bäst lämpad att använda i flervåningshus ur bland annat miljö-, arbetsmiljö- och brandsynpunkt. Detta uppnås genom en litteraturstudie som fokuserar på ämnet brandskyddsmetoder av trä och genom två försök genomfördes för att testa obehandlat, brandskyddsimpregnerat och brandskyddsmålat trä. Ett försök testade bärförmågan efter brandpåverkan, andra undersökte ytskikt, och båda försöken testade brandmotstånd. Bärförmågan testades genom att brandpåverkade reglar blev utsatta för en central punktlast i en Instron- maskin. Ytskikten prövades genom ett enklare försök baserad på testmetoden SP FIRE 105 på tre fasader. En obehandlad, en brandskyddsimpregnerad och en brandskyddsmålad. Mätningar och dokumentation gjordes med bland annat mätinstrument som plattermoelement och filmkamera. Båda typerna av brandskyddsmetoder kräver en kemisk framställning som varken är bra för naturen eller människan. Produktionen är automatiserad och därmed inte någon risk för någon människa. Den färdiga produkten är varken skadlig för miljön, människor eller djur, sålänge inte produkterna förtärs i större omfattning. Resultatet från undersökningen av de tre olika fasaderna visade att det brandskyddsimpregnerade virket klarade sig bäst i alla fem kategorier: bärförmåga, brandmotstånd, ytskikt, miljöpåverkan och arbetsmiljö. Slutsatsen är av det två typer av brandsskyddsmedel för trä som testades, är brandskyddsimpregnering den mest lönsammaste alla fem kategorier. Produkten är lätthanterad, avger inga farliga gaser och är i snitt inte dyrare än det obehandlade materialet. Dock är det viktigt att tänka på brandskyddsarbete och inte släppa på säkerheten för att konstruktionen byggs med brandskyddsimpregnerat trä.

BACKGROUND: Formalized risk management (RM) is an internationally accepted process for reducing hazards in the workplace, with defined steps including hazard scoping, risk assessment, and implementation of controls, all within an iterative process. While required for all industry in the European Union and widely used elsewhere, the United States maintains a compliance-based regulatory structure, rather than one based on systematic, risk-based methodologies. Firefighting is a hazardous profession, with high injury, illness, and fatality rates compared with other occupations, and implementation of RM programs has the potential to greatly improve firefighter safety and health; however, no descriptions of RM implementation are in the peer-reviewed literature for the North American fire service. METHODS: In this paper we describe the steps used to design and implement the RM process in a moderately-sized fire department, with particular focus on prioritizing and managing injury hazards during patient transport, fireground, and physical exercise procedures. Hazard scoping and formalized risk assessments are described, in addition to the identification of participatory-led injury control strategies. Process evaluation methods were conducted to primarily assess the feasibility of voluntarily instituting the RM approach within the fire service setting. RESULTS: The RM process was well accepted by the fire department and led to development of 45 hazard specific-interventions. Qualitative data documenting the implementation of the RM process revealed that participants emphasized the: value of the RM process, especially the participatory bottom-up approach; usefulness of the RM process for breaking down tasks to identify potential risks; and potential of RM for reducing firefighter injury. CONCLUSIONS: As implemented, this risk-based approach used to identify and manage occupational hazards and risks was successful and is deemed feasible for U.S. (and other) fire services. While several barriers and challenges do exist in the implementation of any intervention such as this, recommendations for adopting the process are provided. Additional work will be performed to determine the effectiveness of select controls strategies that were implemented; however participants throughout the organizational structure perceived the RM process to be of high utility while researchers also found the process improved the awareness and engagement in actively enhancing worker safety and health.

The storage of pressure liquefied gas in vessels is subject to various regulations and codes of practice. For example, Liquefied Petroleum Gas (LPG), a commercially relevant product, is subject to Health and Safety Executive Guidelines regarding cylinder/tank arrangements and spacing. In the event of an incident involving fire, the internal pressure and shell temperature of an LPG vessel will rise, and the weakening of steel at elevated temperatures can result in the structural failure of the shell. This can be avoided by the fitting of pressure relief valves, which vent material at a pre-set pressure. However, an ignited release can create a high velocity jet flame which, because of significant radiative and convective components, can generate intense, localised heat loads on neighbouring vessels or pipe-work. However, existing codes of practice have no special provision for the possibility of jet fire incidents. Owing to a lack of detailed information on the thermal response of a LPG vessel exposed to jet flame impingement, a series of laboratory scale tests with simulated, localised jet fire impingement on the exterior shell of a pressure vessel was required. The thermal response and the effects of key parameters, Le. fill level, magnitude of heated zone (Le. size and intensity) and position of simulated impingement, could then be examined for the part-validation of a suitable computer model. In addition, these studies could be used to interpret the results from concurrent full scale jet fire impingement trials. An appropriate pressure vessel was constructed to standard design codes, which incorporated a vent line and dump tank. A suitable LPG substitute was selected. Results from the studies indicated that mixing, and therefore thermal stratification, was highly dependent on the size of the heated zone and its position in relation to the liquid/vapour interface. High Speed Micro-Cinematography was successfully employed to film individual bubble streams within the vessel and to measure individual bubble sizes and velocities for various experimental configurations. Studies were also made on the venting characteristics. Sudden pressure relief caused severe agitation of the liquid phase and the breakdown of thermal stratification. In addition, swelling and aerosol generation through homogenous boiling within the liquid phase was observed. Comparisons with the nodal computer model revealed that the use of only single vapour and liquid nodes was a poor approximation to the detail observed in the small scale studies, where the incident heat flux was relatively low and the simulated region of impingement was highly localised. However, the bulk liquid and vapour temperatures and the pressure response up to the time of venting was generally well predicted. As the degree of engulfment increased the model became a better approximation. Although the full scale trials employed an almost fully engulfing jet flame rather than point source impingement, comparisons have allowed understanding of the liquid and vapour thermal gradients, and the subsequent breakdown of these during venting.

Wildfires and prescribed burns are important sources of air pollutants and can significantly affect air quality at urban locations across large regions. Air quality forecasts generated with Eulerian numerical models can provide valuable information to environmental regulators and land managers about the potential impacts of fires. However, the ability of these models to simulate concentrated fire-related smoke plumes is limited since they lack fire specific physics and chemistry. A sub-grid plume model was coupled with a chemical transport model to address this issue. The modeling framework centered on a fire plume transport model, Daysmoke, and the Community Multiscale Air Quality modeling system (CMAQ) is used to simulate several fire episodes. The studied episodes were used to understand uncertainty in fire emissions and its effect on plume transport modeling and to verify the coupled system’s performance. The system was also used to simulate prescribed burning scenarios with five varying parameters: age of fuel bed, season, acreage, ignition type, and time of the day. Key findings relating to burn efficiency and emission reduction on future prescribed burnings will be discussed.

published_or_final_version / abstract / Conservation / Master / Master of Science in Conservation

published_or_final_version / Public Administration / Master / Master of Public Administration