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The paper analyses the breathing air consumption among participating firefighters during full-scale tests performed in the Tistbrottet mine in Sweden 2013. The availability of breathing air during firefighting has in earlier work been identified as a critical tactical factor in underground firefighting. Results from the tests show that there are differences in the breathing air consumption and that this depends on the methods used, equipment and the workload. The use of BA-teams, i.e. firefighters equipped with breathing apparatuses, is a complex group activity where the largest breathing air consumer will set the limits for the whole team. Light equipment and a structured command and control during the activities will enhance the endurance and the firefighting performance. Equipment and methods affect both firefighting performance and the durability of the firefighting activities. Examples of tested methods and equipment during the test series are: different variations of conventional hose lay-out; CAFS; cutting extinguisher; and trolley for equipment and complementary air. The aid of additional air supply and the use of trolleys will support the activities but is dependent on a large degree of preparation and training to function properly. Based on the tests, it is concluded that the larger model of air bottles should be considered for distances longer than 75 m. 

With the purpose to increase the knowledge on human behaviour when evacuating along elevated platforms, an experiment was carried out at the subway station of Skarpnäck, Stockholm, in October 2016. The overall project objective was to develop basic data for guidelines regarding fire safety design concerning evacuation along elevated platforms. The experiment was designed as a group experiment divided into five different scenarios. In total, 111 persons of mixed gender and age participated. The results from the experiment show that the flow rate along the elevated platform decreased as the walkway was getting narrower. It could also be seen that along the first half of the walkway, where a train was located on the rail track next to the elevated platform, the flow rate was higher and the width of the walkway was used to a lager extent compared to the second half of the walkway where the platform was open to the track area. One of three wheelchair users who participated in the experiment expressed discomfort caused by the height and the width of the walkway and nearly half of the participants experienced problems with passing others walking slower than themselves. 

The paper describes full-scale fire-fighting tests performed in an underground mine. A total of six different methods to fight a full scale fire in a mine tunnel were tested. The methods involved different fire-fighting equipment but were comparable regarding fundamental conditions such as length of response-route, fire-fighting set-up, and smoke and fire size. The aim was to compare different equipment and methods to reach and eventually extinguish the fire. Fire fighters using breathing apparatus (BA) were monitored regarding air consumption, movement speed and local actions and decisions. The results are presented and analyzed in respect to fire-fighting efficiency, front BA operations including moving speed and performed actions, as well as the time to successfully put out the fire. Measurements of heat release rates, temperatures and moving speeds are given in order to quantify the efficiency of the operation. Results indicate that a timespan of 15-30 min is needed for the firefighters to reach the fire source and achieve the extinguishing criteria in five of the tests. The standard equipment and nozzles shows good performance in the tests. A limiting factor on the firefighter's endurance is the amount of air that is available. As a result from these findings the endurance of BA-teams could improve if focus is put on team organization, lightweight equipment and air supply.

The need for a successful fire and rescue operation in an underground facility, e.g., a tunnel, introduces challenges both in the planning phase and during the incident. This is because these types of facilities can be very complex, and thus, specific tactics are needed compared to the more common incidents, e.g. in residential premises. When planning a fire and rescue operation and developing the tactics many different aspects need to be considered: complexity of the facility, the expected number of people involved in the operation, information available about the incident, the purpose of operation, etc. This paper contains recommendations for firefighting in underground facilities. The recommendations are structured in accordance to the sequential time period during which some specific fire safety design measures are taken. These periods are the design phase, the construction phase and finally when the facility is in operation. The recommendations presented in this paper are based on the results of the Swedish TMU research project (Tactics and methodologies for firefighting in underground facilities), results from other research projects and experience from real fire and rescue operations.

The report contains recommendations for firefighting in underground facilities. This implies results from a research project and the recommendations are based on case studies, interviews, experiments and discussion with different fire departments. The recommendations are structured in accordance to the time period of the actual incident occurrence or the time period during which some specific measures are taken. These periods are project period, construction phase and finally when the facility is in operation. The recommendations are based on the work in the TMU project (Tactics and methodologies for firefighting in underground facilities), results from other research projects and experience from real fire and rescue operations.  

The report compiles the results from the TMU-project. The focus is on fire-fighting performance, capability and organization in underground constructions. The emphasis was on large-scale testing with authentic fire conditions and fire-fighting equipment, development of tools for prediction of hazardous conditions and capabilities of  fire-fighting during different conditions, organizational management and tactics, education and development  of recommendations.  The project was divided into different work packages and these are presented in this final summary report. The test fires performed in the project created severe conditions for fire-fighters who moved in smoke for over 180 m before fighting fully developed fires in a range of 18 to 33 MW. The fires consisted of wood pallets placed in a semi-open steel container, simulating a train wagon fire. The walking speed and connection time for hoses and connections were registered and documented by infra-red cameras. The most important results from these tests is that the time taken to approach the fire depends on parameters as type of equipment, preparation, possibilities for use of infra-red (IR) cameras and the capacity of the extinguishing media. The heat radiation from the fire was found to be important to overcome in order to get close enough to fight the fire. Recommendations and tactics for fighting fires in underground constructions are given. 

Results of a simple flow model to describe the entrainment into the air cone created by a positive pressure ventilator (PPV) fan are compared to experimental data. Velocity profiles measured in the air cone of a conventional PPV ventilator are used. The entrainment coefficient and the cone angle were determined for the fan investigated. The correspondence between calculated and measured values is discussed and disparities explained. The findings from the tests are turned into practical guidance for the fire brigade and the advantages and limitations of the simplified model are discussed.

Within the interdisciplinary research project METRO, two full-scale fire tests were performed with ignition inside commuter train carriages in a tunnel. Both tests developed to fully flashover conditions. The fire development was very different in the two tests. The main reason was the difference in initial combustion behaviour between the case with combustible wall and ceiling lining, and the case with a refurbished carriage using aluminium sheet covering the combustible lining as the exposed interior surface. In the case with combustible lining a ceiling flame was developed, radiating towards the seats and the luggage spreading the fire more quickly than in the case without exposed combustible lining. Also in the gas concentrations, significant differences could be observed between the two tests. During the tests, concentrations of O₂, CO and CO₂ were sampled and analysed at three different heights. The paper focuses on the time resolved results of the gas concentration. The development in gas concentration at different levels is presented and discussed in relation to the fire development in the carriage. Results from calculations of time to incapacitation and fractions of an incapacitating does are also included.

I oktober 2013 genomfördes sex fullskaliga brandförsök med kombinerat förflyttnings och släckmoment i Björka Minerals dolomitgruva i Tisbrottet i Sala. Tidigare har dessa två moment inte kombinerats under kontrollerade former där mätningar och observationer dokumenterats i så omfattande grad som i denna försöksserie. Rökdykarnas uppgift vid samtliga av försöken var att avancera in i tunneln och släcka branden. De sex olika försöken utgjordes av konventionell slangutläggning med slangkorgar respektive bärsele, utlägg med tomt system fram till brandplatsen, CAFS, skärsläckare och konventionell slangutläggning med hjälp av materielvagn och depåluft. Försöken visade att konventionell slangutläggning tar lång tid i anspråk, men att utlägg med tomt system och bärsele kan korta tiderna och minska belastningen. Försöken visade också att system med lägre vattenflöden hade möjligheter att slå ner branden, men att mängden vatten var avgörande för att undvika återantändning. Värmekameror är generellt inte anpassade för tunnelmiljöer och ett stort behov finns för vidare utveckling av både utrustning och utbildningsmaterial.

In October 2013 six full-scale fire tests were performed with combined movement and extinguishing in the Tistbrottet Mine in Sala. Earlier these two parts have not been combined under controlled test conditions, where measurements and observations have been documented as thouroughly, as in the Tistbrottet test series. The BA fire fighters task, in all performed tests, were to advance into the tunnel and extinguish the fire. The six different tests were represented of conventional hose lay-out with hose baskets, conventional hose lay-out with hose harnesses, full hose lay-out with empty system until reaching the scene of the fire, CAFS, cutting extinguisher and conventional hose lay-out with wagon aided movement and depot air supply. The tests showed that conventional hose lay-out with water filled hoses is time consuming, but that bot hose harnesses and later filling of the hoses can shorten the time. It was also shown that systems with lower water flows initially effectively can fight the fire, but that the amount of applied water is cruicial for if re-ignition occurs or not. Thermal image cameras are generally not customized for use in underground constructions and further development of both equipment and education material is needed.