The firefighting performance of eleven PFAS-free firefighting foams was evaluated using different fuels (Jet A1, commercial heptane and diesel) and types of water (freshwater and synthetic sea water). Moreover, different firefighting foam generation techniques and application methods were evaluated. The firefighting foams were generated as aspirated foams or as compressed air foams (CAFs). The results for CAF showed a higher performance, with respect to extinction time and burn-back resistance, compared to the foam generated using a UNI 86 nozzle. The CAF was not optimised, indicating a further potential of this foam generation technique. The results indicate that the time to fire knockdown decreases with decreasing foam viscosity. The heat flux was shown to be small, although the entire fuel surface was involved in the fire. The tests showed a dependence on fuel type; different products performed differently depending on the fuel. Tests using sea water showed that addition of salt to the foam solution generally prolonged the extinction time, although for one of the firefighting foams a shorter extinction time was observed. Out of the eleven evaluated PFAS-free products there was no product that outperformed the rest. None of the products in the study met the fire test performance requirements in all the referenced standards. Instead, the products seem to have different niches where they perform best e.g., with different types of fuel or water.

The ETANKFIRE project is focused on tank fires involving ethanol; the work conductedin this part of the ETANKFIRE project (WP1 and WP2) has been focused on tankfirefighting operations.Two series of fire extinguishing tests in reduced scale have been conducted. Both testseries simulated tank fire conditions by using a large amount of fuel and long preburntimes. The influence of foam application techniques, foam characteristics, and applicationrates have been investigated. Some tests have also included alternative extinguishingmedia such as cellular glass, liquid nitrogen and aqueous vermiculite dispersion (AVD).In total 29 extinguishing tests were conducted in the first test series using a 0,41 m2 firetray and 14 tests were conducted in the second test series using a 3,14 m2 fire tray. Priorto the experimental work a literature review was conducted to gain experience, both fromreal tank fire incidents and from various test and system design standards for the use offoam on water-miscible fuel fires.The results showed the importance of the characteristics of the finished foam. Higherfoam expansion ratios and longer drainage times resulted in significantly improved fireperformance. These improved foam characteristics are dependent on the foam applicationhardware as well as the foam concentrate formulation. To obtain these improvedcharacteristics the foam concentration was increased to 6 % from a nominal value of 3 %On the other hand, the improved foam characteristics allowed the application rate to bereduced by 50 % without compromising extinguishing performance. This shows that theperformance requirements in existing test standards for foam (e.g. UL 162, EN 1568) donot provide an incentive for manufacturers to formulate their foam to handle more severefire conditions, such as a tank fire scenario.The tests also indicated that gentle application of the foam is not guaranteed by the use offoam pourers (Type II discharge outlet according to NFPA 11) as the foam was not ableto flow gently along the tank wall due to high steel temperatures.With respect to alternative media, applying a layer of cellular glass followed by foamapplication made the extinguishing operation even more robust.The overall conclusion is that fighting ethanol tank fires would very likely result in afailure to extinguish if standard firefighting operations are used. However, the test resultsalso indicate important parameters that would improve the possibilities for a successfulextinguishment. Further validation of these results in larger scale could also providepossibilities to improve foam system standards, e.g. NFPA11 and EN 13565-2 forextinguishment of water-miscible fuels as well as test standards for foam concentrates(e.g. UL 162, EN 1568-4).Key words: ethanol, fire extinguishment, fire suppression, tank fire, tactics, foam, foamconcentrate, CAF, liquid nitrogen, vermiculite, cellular glass.

The report presents the main results of the six large-scale tests with different types of fixed firefighting system (FFFS) that were carried out in the Runehamar tunnel in June 2016. It describes the background to the tests and the performance of the different systems, and draws conclusions regarding the efficiency of the systems. The fire load consisted of 420 standardised wooden pallets and a target of 21 wooden pallets. Five of the tests were carried out with a 30 mlong deluge zone delivering varying water densities using three different types of side-wall nozzle and an interval distance of 5 m. One test with 93°C glass-bulb nozzles (sprinkler head) in the same zone was also conducted. In the five deluge tests, the detection system was simulated using thermocouples in the tunnel ceiling. The alarm was registered when the ceiling gas temperature reached 141°C, and the system was activated manually after a delay of 4 minutes. The protection goal of the system was to prevent fire spread to a target positioned 5 m from the rear of the main fuel area, and to ensure that the fire did not exceed 30 MW in size. The system setups tested were found to meet these goals.