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 ...