Initial backdraft experiments

A number of large scale backdraft experiments are decribed in this report. A total of 13 experiments have been carried out. During the experiments have several physical properties such as temperature, pressure, gas concentration have been measured. Example graphs are shown in the report. The experimental apparatus as well as the measurments are described in detail in this report. It is difficult to describe the backdraft phenomena strictly in quantitative terms, mut the measurements give a good description of the phenomena in a qualitative way.