Små och storskaliga släckförsök med CAF och A-skum mot vätskebrand av bensin

• Main Author: Lindsjö, Elin
• Format: Bachelor Thesis
• Language: Swedish
• Published: 2015
• Subjects: Technology; Teknik; Compressed air foam; CAFS; A-skum; släckförsök; Nozzle; Nozzle The; Luleå
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-58087

The rescue service in Luleå took an initiative in 2014 and completed a try-out with CAF-system and A-foam against a liquid fire of kerosene. The use of the CAF system against liquid fires is in great interest because increased use of A-foam could lower the use of film-forming foams that contain harmful fluorinated substances. This would lead to positive effects on the environment.The try-out in 2014 was successful and indicated that CAF-system with A-foam was a good extinguisher. Luleå rescue service began planning more large-scale try-outs, this time against gasoline fires and this study is part of that project. The aim of this study has been to get an idea of the extinguishing capacity of CAF-system and A-Foam. A literature search showed that no tests similar to those envisaged in this project were documented. The empirical study consisted of 12 small- and 2 large-scale experiments. The liquid that were used in the experiment were gasoline. The small-scale experiment followed the SP-Method 2580 and the large-scale experiment where conducted in a 60 m2 large pit. A summary of the small-scale experiment shows that no control over the fire was obtained when the foam was applied by a direct deposition technique. The foam strikes in to the fuel too hard and the blanket of foam broke down faster than new foam was applied. It required a soft deposition technique to control the fire at the small-scale experiment. The first large-scale experiment failed when no correct foam quality was obtained during the try-out. The second try-out started with the use of a traditionally CAF nozzle, which produces wet heavy foam, and no control of the fire was obtained. The foam equipment had to be changed to a medium expansion nozzle before the fire could be controlled. With the medium expansion nozzle the fire was extinguished in about 5 minutes. More expanded foam, which results in smoother application, was needed to control the fire at the large-scale experiment. The application technique is important when extinguishing fires with ...