This study is a part of the project named Documentation of active fire fighting systems as a fire safety design parameter. This report submits the experimental results from the medium scale experiments. The experimental data are presented in a form of a data report.

The test series focuses on the interaction between the deluge water and flames. It is carried out in an 8 m high test rig and is denoted the medium scale series. A total amount of 54 tests were carried out with different nozzels, fire size, water pressure, ventilation, extinguishing media and nozzle elevation. Five different nozzels in flames forming 5MW to 8MW gas fires are tested. Air-to-fuel rates are also varied.

The results are measured in terms of reduction of heat production, measured by a large industry calorimeter constructed as a part of the test rig. Changes in radiative and total heat load to the rig walls and gas temperatures are included in the measurements.

The efficiency of increasing water aplication rate is strongly dependent on the nozzle characteristics and the dependency on water application rate is most dominant when dealing with fuel rich fires. Possible factors for the resulting reduction of heat release rate include droplet size, application pressure, volume fraction of water in the exhaust gas. nozzle footprint and nozzle elevation.

This report replaces report no STF22 F99 of 2000-01-10. The only difference is that the current report is unrestricted.