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Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: Deap-seated fire; flow calculation; maximum percent of agent in pipe; free efflux; carbon dioxide extinguishing system; low pressure; no efflux; surface fire; NFPA 12. Includes bibliographical references (p. 69-70).

Thesis (M.S.)--Worcester Polytechnic Institute. / Keywords: clean extinguishing agent; c₆f-ketone; novec 1230; thermal decomposition products; halon alternative. Includes bibliographical references.

Släckvatten är den biprodukt som blir kvar efter att en brand är släckt och innehåller många olika föreningar som är skadliga för miljö och hälsa. Till exempel kan ett utsläpp av släckvattenslå ut en vattentäkt som tar många år och kostar många miljoner att återställa, om det ens går. Vissa av föroreningarna kan även stanna i organismer genom hela näringskedjan. Ett bättre handhavande av släckvatten skulle med andra ord kunna leda till stora ekonomiska och miljömässiga vinster. Syftet med denna rapport är att undersöka hur svensk släckvattenshantering kan utformas. Rapporten undersöker hur organisation, utbildning, rutiner, teknisk förmåga, förmågan att rena släckvattnet kan se ut runt en släckvattenresurs hos svenska räddningstjänster. Dessutom undersöker rapporten om det finns behov av stöttning från en annan aktör när det gäller släckvattenshanteringen. Rapporten berör endast hantering av släckvatten på skadeplatsen. Metoden som valdes för rapporten är fallstudie, där det ingick en litteraturstudie samt en intervjustudie. Tre organisationer valdes ut för intervjuerna: Södra Älvsborgs Räddningstjänstförbund, Eskilstuna Räddningstjänst, Myndigheten för samhällsskydd och beredskap (MSB). Resultatet visar att de två räddningstjänsternas släckvattenresurser liknar varandra i alla de områden som rapporten berör. Det framkom även att MSB påbörjat ett arbete för att utveckla släckvattenshanteringen med riktlinjer och vägledningar. De slutsatser som kan dras av resultatet är att organisationen runt en släckvattenresurs bland annat är att resursen inte ingår i någon larmplan utan larmas ut separat av RL. Resursen har placerats på en RIB- eller värnstation för att sprida kompetensen i organisationen samt så att resursen inte ska störa styrkeuppbyggnaden för andra stationer. Resursen har eget befäl och mellan 3–4 brandmän. Det finns samarbete mellan kommuner/förbund både ekonomiskt och operativt för de undersökta släckvattenresurserna. När det gäller utbildning för dem som arbetar med släckvattenresursen hålls årliga helgövningar plus ytterligare 3h utöver det hos Eskilstuna och hos SÄRF övas materialkännedom kontinuerligt. Befälen som arbetar med resursen har ingen påbyggnadsutbildning om vilka föroreningar som finns i vattnet utan ska kunna bedöma släckvattnets farlighet utifrån vad som har blivit släckt. Alla insatser utvärderas av personalen som varit på insatsen som sedan berättar för dem som inte varit med. Det är enligt respondenterna svårt att samla upp släckvatten då förutsättningarna kan se olika ut på olika insatser. Detta gör att det inte går att ha några förbestämda rutiner, checklistor eller lathundar. En taktik som dock finns är att leda vattnet mot en svacka eller dagvattenbrunn som förses med en pumpgrop för att sedan pumpa vattnet till en bassäng eller ett uppsamlingskar. Det finns rutiner för bränder på vattenskyddsområde som bygger på försiktighetsprincipen. De rutiner som finns för uppsamling inomhus är att brunnar i industrilokaler täpps till. Uppsamlingen påbörjas oftast efter att livräddande insats är klar och uppsamlandet sker mellan kall och varm skyddszon. Den tekniska förmågan för släckvattenhantering i basbilarna, där släckande styrka åker, är begränsad och förväntningen är att kunna samla upp genom att täta dagvattenbrunnar och lägga ut fylld grovslang som barriär. Fordonet som de undersökta släckvattenresurserna baseras på är en pick-up med släp. Släpet får max väga 750kg för att undvika krav på utökad körkortsbehörighet. Personalen bär larmställ, hjälm, stövlar med stålhätta, gummihandskar, skyddsglasögon och har även tillgång till tryckluftsapparat. Hanteringen av kontaminerad utrustning följer Skellefteåmodellen för friska brandmän. Utrustningen på resursen består främst av: brunnsmattor och brunnstätningar, självresande kar, dränkbara pumpar, spillbarriärer, vattendammsugare, pumpgrop och bärbara elverk. Uppsamlingsförmågan varierar mellan 10 – 26 m3 vilka gör att uthålligheten för uppsamlingen varierar mellan 20 minuter och 2,5 timmar beroende hur många av pumparna som används. Förmågan för rening är i dagsläget lika med noll och det beror mycket på att räddningstjänsterna inte har råd med reningsverk. Stöttning från MSB efterfrågas främst kring det otydliga juridiska ansvaret för släckvatten samt metodutveckling. Sedan efterfrågas stöttning rent operativt när det gäller rening och provtagning av släckvatten. Det kan antingen komma från MSB men kan också komma från samarbete mellan räddningstjänster/förbund eller med andra kommunala verksamheter så som miljö- och servicekontor eller VA. / Extinguishing water is the by-product remains after a fire has been extinguished. It contains many different compounds that could harm the environment and health. A spill of extinguishing water could e.g. destroy a water source that might take many years and costs many millions to restore, if even possible. Some of the pollutants can also stay in organisms throughout the food chain. In other words, better management of extinguishing water could lead to major economic and environmental benefits. The purpose of this report is to investigate how Swedish extinguishing water management can be designed. The report examines how organization, training, routines, technical ability, the ability to purify the fire water can be done around a fire water resource at Swedish rescue services. In addition, the report examines whether there is a need for support from another actor in terms of fire water management. The report only concerns the handling of extinguishing water at the accident site. The method chosen for the report is a case study, which included a literature study and an interview study. Three organizations were selected for the interviews: South Älvsborgs Rescue Services Association, Eskilstuna rescue service and the Swedish Civil Contingencies Agency. The results show that the two examined extinguishing water resources are very similar in all the areas covered by the report. It also emerged that MSB has begun work to develop guidelines for extinguishing water management. The conclusions that can be drawn from the result are that the organization around an extinguishing water resource is, e.g., that the investigated resources are not included in any alarm plan but is alerted by RL. The resource has been placed at a RIB or part time station to spread the competence in the organization and so that the resource does not interfere with force building for other stations. The resource has its own commander and between 3-4 firefighters. For both investigated resources, there is cooperation between several fire departments both financially and operationally for the extinguishing water resource. When it comes to training for those who work with the fire water resource, annual weekend exercises are held plus an additional 3 hours per year. Knowledge of how to use the equipment is practiced continuously. The commanders who work with the resource have no additional training in what contaminants that could be expected to be present in the water but must be able to assess the danger of the extinguishing water based on what has been extinguished. All rescue efforts are evaluated by the staff who have been on the rescue, who then tell those who have not participated. According to the respondents, it is difficult to collect extinguishing water as the conditions vary a lot for different rescue efforts. This means that it is not possible to have any pre-determined routines, checklists or guides. One tactic that exists, however, is to direct the water towards a depression or stormwater well provided with collection vessel and then pump the water to a pool or a collection tank. There are routines for fires within water protection areas that are based on the precautionary principle. The routines that exist for indoors collection are that wells in industrial premises are being clogged. The collection usually starts after the life-saving operation has been completed and the collection takes place between a cold and a warm protection zone. The technical ability for extinguishing water management in the base cars is limited and the expectation is to be able to collect by sealing stormwater wells and laying out filled coarse hose as a barrier. The vehicle on which the fire water resource is based is a pick-up with a trailer. A trailer that may weigh a maximum of 750 kg as then no extended driving license is required. The staff wears alarm racks, helmets, boots with steel caps, rubber gloves, goggles, and also has access to a compressed air device and the handling of contaminated equipment follows the “Skellefteå model” for healthy fire fighters. The equipment on the resource mainly consists of well mats and well seals, self-erecting tubs, submersible pumps, spill barriers, water vacuum cleaners, pump pits and portable power plants. The collection capacity varies between 10 - 26 m3 which means that the endurance for the collection is between 20 minutes and 2.5 hours depending on how many of the pumps that are being used. Today, the capacity for treatment of the extinguishing water is equal to zero, largely since the rescue services cannot afford mobile treatment plants. Support from MSB is requested regarding the unclear legal responsibility of the extinguishing water, as well as for method development. Also operational support is asked for, in terms of treatment and sampling of the extinguishing water. Such support could either come from MSB but also from cooperation between rescue services or with other municipal activities such as environmental and service departments or water and wastewater departments.

The thermal decomposition products (TDP) generated during fire suppression with 1,1,1,2,2,4,5,5,5 nonafluoro-4-trifluoromethyl pentan-3-one were studied using wet chemistry and FTIR. Small-scale testing was conducted in a 1.28-m3 (45-ft3) enclosure. The effects of fire size, agent discharge time, and agent concentration on TDP are reported. A comparison of the two methods is presented. In terms of magnitude and generation trends, the TDPs were found to be comparable to other in-kind halon alternatives.

The synthesis of bromochloromethane (BCM) in a batch reactor, using phase transfer catalysis, was investigated. During the synthetic procedure, sodium bromide (100.0g, 0.97mol) along with an excess amount of dichloromethane (265.0g, 3.12 mol) was charged to a reactor containing benzyl triethylammonium chloride (13 mmol), dissolved in 50 ml of water. The bench scale reactions were all carried out in a Parr 4520 bench top pressure reactor coupled to a Parr 4841 temperature controller. The method produced a 50.0 percent yield of the product BCM after a reaction time of 12 to 13 hours. The main objective for this investigation was to optimize the abovementioned reaction with respect to yield and reactor throughput. Quantitative analysis of BCM was performed on a Focus Gas Chromatograph, fitted with a flame ionization detector, and a BP20 column (30m × 0,32mm ID × 0,25 mm). Delta software, version 5.0, was applied for data collection and processing. The injector and detector port were set at 250°C and 280°C, respectively. The oven temperature was set and held at 40°C for a period of 2 minutes, then gradually increased at a rate of 10°C/min to 130°C, with the final hold time set for 1 minute. An analytical method for the quantitative analysis of BCM was developed, optimized and validated. Validation of the analytical method commenced over a period of three days, and focussed the following validation parameters: Accuracy, precision, and ruggedness. Statistical evaluation of the results obtained for precision showed that the error between individual injections is less than 2 percent for each component. However, ANOVA analysis showed a significant difference between the mean response factors obtained in the three day period (p-value < 0.05). Thus we could conclude that the response factors had to be determined on each day before quantitatively analyzing samples. The accuracy of the analytical method was assessed by using the percent recovery method. Results obtained showed that a mean percent recovery of 100.18 percent was obtained for BCM, with the absolute bias = 0.0004, and the percent bias = 0.18 percent. Hence the 95 confidence intervals for the percent recovery and percent bias are given by: (Lz, Uz) = (100.56 percent percent 102.15 percent), 13 (LPB, UPB) = (0.56 percent, 2.15 percent), respectively. Since the 95 percent confidence interval for the percent recovery contains 100, or equivalently, the 95 percent confidence interval for percent bias contains 0, the assay method is considered accurate and validated for BCM. In the same manner the accuracy and percent recovery for DCM and DBM was evaluated. The method was found to be accurate and validated for DBM, however, slightly biased in determining the recovered amount of DCM. With the analytical method validated, the batch production process could be evaluated. A total of six process variables, namely reaction time, water amount, temperature, volume of the two phases, stirring rate, and catalyst concentration, were selected for the study. The effects of the individual variables were determined in the classical manner, by varying only the one of interest while keeping all others constant. The experimental data generated was fit to a quadratic response surface model. The profile plots that were obtained from this model allowed a visual representation of the effect of the six variables. The experimental results obtained showed that the reaction follows pseudo zero-order kinetics and that the rate of the reaction is directly proportional to the concentration of the catalyst. The reaction obeys the Arrhenius equation, and the relatively high activation energy of 87kJ.mol -1 signifies that the rate constant is strongly dependent on the temperature of the reaction. The results also showed that the formation of BCM is favoured by an increase in the reaction temperature, catalyst concentration, and a high organic: aqueous phase ratio. Thus the synthesis of BCM using phase transfer catalyst could be optimised, to obtain a 100 percent yield BCM, by increasing both the reaction temperature to 105°C, and the concentration of the phase transfer catalyst -benzyl triethylammonium chloride - to 5.36 mol percent. The reaction time was also reduced to 6 hours.

The dynamic development of industry and the constant production of new substances affecting the environment is currently one of the priorities of the interests of the human population. This thesis is focused on the ecotoxicological evaluation of selected extinguishing agent which are applied in case of fire. They must effectively extinguish fire because a live protection and material resources in any case very important, but Theky should be also environmentally friendly. In this work were tested surfactants, which are the main component of foaming extinguishing agent with the following commercial names: STAMEX F-15, F-15 EXPYROL, MOUSOL APS F-15, FINIFLAM F-15 and PYROCOOL B. Since surfactants have a negative impact mainly on aquatic ecosystem assessment were mainly used ecotoxicity tests using aquatic organisms. Test organisms were aquatic crustacean Daphnia magna and Thamnocephalus platyurus aquatic dicotyledons plant Lemna minor and terrestrial monocotyledons plant Sinapis alba. Based on the results of the tests were values of LC50, EC50 and IC50 for the tested substances determined and their ecotoxicity compared.

Konstruktionsbränder kan idag orsaka stora problem för räddningstjänsten. Släckningsarbeten vid konstruktionsbränder brukar idag involvera släckmedel som bygger på vattenbaserade medel. Detta medför att primära skador kan begränsas, men istället uppstår problemet med sekundära skador som mögel eller vattenskador. Idag finns det flertalet släckmedel som används men det finns inga dokumenterade tillfällen där flytande kväve och/eller koldioxid används vid konstruktionsbränder. Branschen har istället funnit användningsområden för flytande kväve vid gruvbränder med flertalet lyckade insatser. Flytande kväve och koldioxidsläckare är båda kylande släckmedel som vid användning uppnår mycket låga temperaturer. Släckmedlen släcker på liknande sätt, båda kyler till en viss del, men den primära släckkällan är kvävning. Flytande kväve får en avsevärd volymutveckling vid fasövergång från flytande till gas. Gasen tränger undan syret i den brandhärjade konstruktionen och kan därmed släcka branden. Koldioxid verkar på samma sätt, kvävande, men i detta fall övergår den kondenserade gasen till fast fas (torr-is) vid aktivering som sedan sublimerar till gas och kväver branden. För att undersöka släckmedlens förmåga att bekämpa konstruktionsbränder samt återantändningsskyddet vid användning, har åtta konstruktioner byggts. De fristående konstruktionerna ska efterlikna ett regelfack från en väggkonstruktion. Vid försöken har fyra konstruktioner använts till att undersöka flytande kväve och fyra konstruktioner för att undersöka koldioxid. Av dessa åtta användes två som testkonstruktioner i syftet att bestämma metod för applicering av släckmedel och anläggning av brand i konstruktionen. För att anlägga en brand i konstruktionerna antändes de i det nedre högra hörnet med hjälp av en propanbrännare. Vid fyra försök applicerades släckmedlen i mitten av konstruktionen i ett hål som borrats för att nå innandömet. Vid de andra två konstruktionerna applicerades släckmedlen vid hålet där branden anlades. För att mäta de temperaturer som uppstod i konstruktionerna placerades fem termoelement i varje konstruktion. I de tre försök där flytande kväve applicerades sjönk temperaturen drastiskt och efter en timme, när försöken avslutades, registrerade inget termoelement temperaturer höga nog för att en återantändning skulle kunna ske. I de tre försök där koldioxid applicerades släcktes två av tre konstruktioner och den tredje återantändes. Fem av sex försök uppvisades en trend där temperaturen låg mellan 12 – 56 °C när försöken avslutades och där temperaturen fortfarande sjönk. En trend påvisades för bägge släckmedlen, där de dröjde kvar i konstruktionen när försöken avslutades, efter cirka en timme. Släckmedlen kunde därmed under en lång tid förångas och påverka den brandhärjade konstruktionen och motverka återantändning. Slutsatsen av detta projekt är att flytande kväve och koldioxid verkar lovande som släckmedel vid konstruktionsbränder. Fler försök bör dock utföras för att styrka resultatet innan ett välgrundat uttalande kan göras. / Today structural fires can cause big problems for the rescue services. Extinguishing structural fires usually depends on methods involving water based extinguishers. These methods entails that the primary damages can be limited although secondary damages like mold or water damage may arise. Today there are several fire extinguishers that are used in the industry but few documented occasions have been found where liquid nitrogen or carbon dioxide is used on structural fires. Liquid nitrogen has long been used for mining fires with success. What liquid nitrogen and carbon dioxide in extinguishers have in common is that they are both cooling agents which upon activation reach very low temperatures. These extinguishing agents both put out a fire in a similar way, they both chill when applied, but that is not the primary source. The primary source of extinguishing comes by suffocating the fire by removing all the surrounding oxygen. The volumetric growth of gas between phase transitions displaces the oxygen present in the fire ravaged construction and thereby extinguishes the fire. Eight constructions were built to test these extinguishing agents and their potential for extinguishing construction fires. The purpose of these constructions was to simulate one part of an entire wall. To perform these tests, four out of the eight constructions were used to examine liquid nitrogen and the other four were used for carbon dioxide fire extinguishers. Two constructions were used as test constructions with the purpose to test different methods for the extinguishing agents as well as setting fire to the construction. A propane burner was used in the lower right corner of the construction to ignite it. The extinguishing agents were applied to the center of the constructions in four tests. In two tests the extinguishing agents were directed at the base of the fire in the lower right corner. A total of thirty thermocouples were used, divided evenly among the six tests that recorded data, with five thermocouples being placed in each construction. In the three tests with liquid nitrogen as extinguishing agent, the temperature dropped drastically. The temperatures registered in the wall by the thermocouples were not high enough to pose any risks for a fire to resurface at the end of the tests. In the tests using carbon dioxide as an extinguishing agent the fire managed to resurface in one out of three tests. In five out of six tests the thermocouples registered temperatures in the range of 12 – 56 °C and continually declining. Both of the extinguishers displayed similar behavior when observed, namely that the extinguishing medias could be observed remaining in the constructions long after the tests ended. This means that the extinguishing agents could evaporate during an extended period of time and counteract any flames from resurfacing. To conclude this report, the good qualities these extinguisher agents exhibit implies that they work well as extinguishing agents to combat construction fires. More experiments should be performed to strengthen the results from this project.

This diploma thesis is focused on the evaluation of effects of the most frequently used extinguishing agents in the South Moravian region on selected aquatic and terrestrial organisms. Extinguishing substances which have been tested are foaming agents Sthamex and Moussol, rigid wetting agent TS ECO and TS Turbo and ABC FAVORIT fire - extinguishing powder. Their effects have been tested on aquatic organisms Daphnia magna and Scenedesmus subspicatus and terrestric organisms such as Folsomia candida, Lactuca sativa, and Eisenia fetida. Validation test on standard substances have been performed to verify the validity of the test results. From the obtained results values of IC50, LC50 and EC50 were calculated, through which the impact of individual extinguishing agents on the components of the environment was assessed.

For gaseous fire extinguishing systems, the maximum percent of agent in pipe, i.e., pipe volume vs. agent liquid volume should be determined for proper system design and performance by confirming the maximum length of pipe run in which their flow calculation methods can predict the discharge pressures and agent concentration. It is the purpose of this paper to determine the ability and limitations of the NFPA 12 flow calculation methodology to identify the maximum percent of agent in pipe by conducting full scale low-pressure CO2 system discharge tests. A total of twenty low-pressure CO2 system discharge tests were conducted under different conditions. If all the measured pressures at the three node points of pipe runs and the measured CO2 concentrations in the test enclosures did not deviate from the predicted values of computerized flow calculations by more than ¡¾10 percent, the tests were judged to be acceptable. In the test results, the low-pressure CO2 system with a pipe run exceeding 492 ft (150 m) was not likely to achieve the concentration required for fire extinguishment within the determined discharge time although the pipe network was installed in compliance with the calculations based on the pressure drop equation in NFPA 12.