Mathematical correlations for the effect of water based fires suppression systems are presened in this report. Some of the correlations are valid for solid fuels only; some are validated for liquid pool fires, but the most useful ones valid for gas phase fires do not have a large-scale experimental verification. The proposed correlations between fire scenario parameters and the characteristics of water sprays will be validated and quantified through large scale experiments, first in a 3 m diameter 8 m high cylindrical test rig, next in a room configuration with an array of spray nozzels mounted in the ceiling.