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Fortifikationsverket (FORTV) has expressed a desire to investigate the design, reliability, performance and cost of a sprinkler system for a typical underground fortification facility. Based on the cost and the benefit associated with a sprinkler system, a cost-benefit analysis was performed. In addition, water mist fire protection systems were studied. The installation cost analysis was based on two fictious facilities; a small facility with a net area of 1 000 m2 and a large facility with a 5 000 m2 net area. The estimated installation cost for a traditional sprinkler system in the smaller type facility is about SEK 1,3 million and about SEK 3,3 million for the larger type facility. The installation cost for a high-pressure water mist system is higher than that of a traditional sprinkler system for the smaller type facility but comparable for the larger type facility. A low‑pressure water mist system seems to be the least expensive option for both types of facilities. This is probably because the system, unlike a traditional sprinkler system, requires smaller pipe sizes, smaller water pumps and a smaller water tank and unlike a high-pressure system uses normal steel pipes and less expensive centrifugal pumps. The cost-benefit analysis for the fictitious type facilities shows that a sprinkler system is cost-effective, especially for the larger type facility. But it should be noted that the uncertainty in the data base is quite large, which means that the trends in the result can be used for further analysis, but that the actual values ​​of the benefit ratio should be viewed with some caution. The sprinkler system mainly has an effect to reduce the property loss. The expected benefit for personal injury is around one percent of the total benefit of the sprinkler system. This is because the risk of fatality and injuries in the event of a fire is small, as people can usually put themselves in safety. The reduction in property loss was assumed to be 75%, and an assumed lowered benefit of sprinklers (50% and 25% property loss reduction, respectively) leads to a lower benefit ratio but for the large type facility the benefit ratio is still above 1,0. The benefit of sprinklers also decreases if the assumed fire frequency is reduced. However, for the larger type plant, the calculation shows that there is still a benefit, even if the assumed fire frequency is halved. The same applies if the cost of replacement of expensive equipment is assumed to be half as high.

Thisreport summarizes the work conducted within the project ”Analysis of physicaldeterminants and technical measures in support of the zero vision” financed bythe Civil Contingency Authority (MSB) in Sweden. The work aims to find measuresto prevent and reduce the number of fatalities in fires in residentialbuildings in a Sweden, a list of such measures is provided in the end of thereport. The list is based on work conducted in several small sub-projects, ashort summary of these is also provided in the report. Denna rapport utgör slutrapport i projektet ”Analys av brandsäkerhetens fysiska bestämningsfaktorer och tekniska åtgärder som stöd till nollvisionen” som har finansierats av MSB. Rapporten sammanfattar projektet i form av förslag på åtgärder som kan införas för att minska antalet omkomna och skadade i bostadsbränder. De rekommenderade åtgärderna baseras på de resultat som framkommit i de underprojekt som genomförts under projektets gång. En kort sammanfattning av de projekten ges, för fullständig information hänvisas läsaren till de olika delprojektsrapporterna. För att minska antalet döda och skadade i bränder i bostäder behövs många olika åtgärder, det finns ingen universallösning som kan förhindra alla dödsfall i bostadsbränder. Åtgärderna som rekommenderas inkluderar: Fortsatt satsning på brandvarnare i hemmet, både i form av fler brandvarnare och bättre brandvarnare Informationsspridning genom t.ex. bättre spridning av sidan ”Din säkerhet” Bättre brandskydd för personer som vårdas i hemmet Brandkrav på lös inredning Fortsatt och förbättrad uppföljning av dödsbränder Mer vikt vid nyttan av brandskyddsåtgärder i regelverk även om det inte går att räkna hem nyttan rent samhällsekonomiskt Fortsatt forskning inom området gällande t.ex. bättre brandvarnare, utvärderingsverktyg olika insatser samt bränder med okänd orsak. Analys av brandsäkerhetens fysiska bestämningsfaktorer och tekniksa åtgärder som stöd till nollvivionen

The shipping industry is facing increasing pressure to cut emissions. Diesel-electric hybrid or fully electrical propulsion systems can offer significant savings in fuel consumption and reduce emissions. However, the use of energy storage battery systems on board vessels is introducing new fire hazards and advice on suitable fire extinguishing systems and agents is desired. In a series of tests, both total compartment application water spray and water mist systems and direct injection (using several different agents) into the module were evaluated in fire tests conducted to compare different fire extinguishing approaches for a fire in a battery cell. A test compartment was constructed to simulate a battery room and a commercially available lithium-ion (Li-ion) battery cell was positioned inside a cubic box that mimicked a battery module. By heating the battery cell, combustible gases were generated, and these gases were ignited by a pilot flame inside the simulated battery module. The tests indicated that fire extinguishment of a battery cell fire inside a battery module is unlikely when using total compartment water spray or water mist fire protection systems. The water droplets are simply not able to penetrate the battery module and reach to the seat of the fire. Direct injection of the fire extinguishing agent inside the battery module is necessary. The tests also showed that agents such as water and low-expansion foam, with a high heat capacity, provide rapid cooling and fire extinguishment. The reduced water surface tension associated with low-expansion foam may improve the possibilities for water penetration whilst agents with a high viscosity may not be able to spread to the seat of the fire. Agents with less heat capacity, such as high-expansion foam and nitrogen gas, provide less cooling but fire extinguishment can still be achieved if designed correctly. The Lion Fire @ Sea project was funded by the Swedish Maritime Administration (Sjöfartsverket) and RISE Research Institutes of Sweden.

The objective of the tests was to determine the water distribution characteristics using different water pressures and sprinkler spacing of two selected Extended Coverage sprinklers. The sprinklers may be used for the protection of the Muskö tunnel and the test set‑up simulated a freight truck trailer positioned inside the tunnel. Adequate sprinkler coverage would require that sprinklers are positioned close to the peak of the ceiling. A relatively short vertical distance from the sprinklers and the ceiling is also essential for proper thermal activation. These requirements are best met by the use of upright sprinklers. Two extended coverage upright sprinklers with a K‑factor of 363 (metric) and 202 was selected for the tests. For the extended coverage upright K363 sprinkler (Tyco model EC‑25), a sprinkler spacing of 4.0 m is recommended, in order to account for the fact that full coverage of the freight truck trailer was not achieved at the tested 4.2 m spacing. A density of 10 mm/min requires an operating pressure of around 0.7 bar at this particular spacing. The tested extended coverage upright K202 sprinkler (Tyco model EC‑14) provided a wider water discharge pattern, with a proper water distribution on the top of a freight truck trailer positioned offset in the tunnel at sprinkler spacing up to 5.0 m. For an actual installation, a K202 sprinkler designed for a density of 10 mm/min require an operating pressure of around 3.6 bar at this particular spacing. Finansierat av RISE Tunnel Underground Safety Center (TUSC).

Electric propulsion using batteries as energy storage has the potential to significantly reduce emissions from shipping and thus the environmental impact. The battery type that is currently on the top of the agenda to be used for ship propulsion applications is Li-ion batteries. Li-ion batteries pose different safety issues than e.g. other propulsion technologies and other batteries such as lead-acid batteries. It is essential that the safety level on board, including fire safety, is maintained, when introducing electric propulsion with energy storage in batteries. This report discusses the different regulations and guidelines available today for fire safety of batteries on board in relation to current knowledge about Li-ion batteries. Also fire safety measures available on board ships today and their applicability for Li-ion batteries is discussed, as well as the different test methods available and their applicability. A workshop gathering different stakeholders from Sweden, Norway and Finland identified fire safety as the main challenge for the introduction of battery propulsion at sea. The workshop concluded that future work is desired in order to increase knowledge and to develop publicly available strategies, training and designs. Säker och kostnadseffektiv introduktion av batteridrift på fartyg

Commercial residential sprinklers are usually fitted with 3 mm glass bulbs having a nominal operating temperature of 68°C or a high-sensitivity solder link, usually with a nominal temperature rating of 74°C. Previous work show that there is a significant potential for improving sprinkler response times in a residential room fire scenario by using glass bulbs with a lower Response Time Index (RTI) and lower operating temperature than commonly used. The objective of this study was to investigate any improved performance due to earlier activation of residential sprinklers. A series of fire tests was conducted inside a test compartment sized 3.66 m by 3.66 m. The fire test source consisted of either a simulated or authentic upholstered chair. For the majority of the tests, the flow rate of the residential sprinkler was 30.3 liter/min (corresponding to the minimum design density 2.05 mm/min as per the recommendations in NFPA 13D and 13R). Additional tests were conducted at 60.6 liter/min (the minimum design density 4.1 mm/min as per NFPA 13). Tests were also conducted with commercial low- and high-pressure water mist nozzles and a stand-alone high-pressure water mist system. The results show that earlier activation of residential sprinklers had a small effect on its performance, especially for the authentic upholstered chair scenario, when flowing 30.3 liter/min. The rather small effect is probably due to that the discharge density was too low to provide fire suppression. When the flow rate was increased to 60.6 liter/min, the performance was considerably improved as compared to the flow of 30.3 liter/min. Any improvement in performance of earlier activation was, however, not investigated for the 60.6 liter/min flow rate. The flow rates of the commercial low- and high-pressure water mist water mist nozzles ranged from 17.2 liter/min to 36.7 liter/min. Roughly, it could be concluded that the performance of the water mist nozzles were comparable or better than the residential sprinkler at approximately half the water flow rate for the tested fire scenarios. The stand-alone high-pressure water mist system had a flow rate of 8.2 liter/min. The performance was comparable to that of the other water mist nozzles in the study The performance was comparable to that of the other water mist nozzles in the study, despite a considerably earlier activation. However, the results indicate that the performance was relatively much influenced whether the simulated upholstered chair was orientated with its front towards the test compartment or with its front towards the back wall (poorer performance). This would suggest that the position of the fire test relative to the position of the unit is a crucial factor and underlines the importance of a thoughtful positioning in practical applications. Analys av brandsäkerhetens fysiska bestämningsfaktorer och tekniska åtgärder som stöd till nollvisionen

Active fire protection systems and products: A review of the performance in residential firesEach year there are in excess of 20 000 residential fires in Sweden and the local rescue services are alerted to just over 6 000 of them. In recent years, around 90 people died in fires annually and the vast majority of these died in a fire in the home. Although the number of fatalities and injuries in fires has decreased in recent decades, it is a slow decline. The objective of the work presented in this report was to investigate whether the use of passive or active fire protection systems or products have the potential to further reduce the number of deadly fires. The investigation was based on a review of national and international experience on the use of fire-safe cigarettes, fire-safe candles, upholstered furniture and mattresses, bedding products, residual current devices, stove top protection systems, home fire alarms, residential sprinkler systems and stand-alone sprinkler systems.

Simple and robust test methodologies that make it possible to measure and quantify the effectiveness of water spray or water mist systems intended for ‘large’ shipboard machinery spaces were investigated. Heat Release Rate calorimetry is usually the best method to measure the effectiveness of a water spray or mist system, although not all fire laboratories have access to such equipment. Therefore, there is a need to explore if other traditional measurement techniques can be used. Such methods include thermocouples, heat flux gages and Plate Thermometers. An additional method, the Pipe Thermometer, has been developed and investigated within the project. It consists of an insulated thin-walled stainless steel tube having an outer diameter of 103 mm with numerous thermocouples welded on the outside surface. The study, which was applied here on a water spray system, shows that the Pipe Thermometer is a possible method to use for evaluation of the efficiency of such system. It is definitely a better method than using heat flux meters or Plate Thermometer which were located at a distance from the fire source. The best correspondence between the measured data below the water spray system and the measured heat release rate was found between the measured gas temperature data and the measured convective heat release data. Consequently, there is no clear advantage of using the Pipe Thermometer (as mounted here) instead of traditional thermocouples at similar locations.

This report describes water mist and water spray system tests inside a simulated machinery space. The tests were conducted inside a compartment measuring 8,0 m by 12,5 m with a ceiling height of 5,0 m. The corresponding volume was 500 m3. The walls and the ceiling were constructed from steel plates. The test compartment replicates an intermediate size machinery space compartment onboard a ship. Either diesel oil or heptane pool fires were used as the fire source. The fires had nominal heat release rates of 500 kW, 1 MW and 2 MW, respectively and were either fully exposed to the water spray or completely shielded by a horizontal obstruction steel plate measuring 2 m by 2 m. Three different systems were tested; (1) a water spray system flowing 500 L/min at 2 bar (this system was designed according to the SOLAS convention), (2) a low-pressure system flowing 97 L/min at 12 bar and (3) a high-pressure system flowing 60 L/min at 70 bar. In addition to the tests using these three systems, free burn tests were conducted inside the compartment. This report contains a description of the test set-up, its instrumentation, the fire test procedures and a limited presentation of the results. A more thorough analysis of the test results will be made in subsequent reports, articles and papers.