This report comprises the summary of the results obtained by the project "Effect of deulge water on oil- and gas type fires". It sums up results from major experimental research projects, medium-and-large-scale dedicated experiments with typical deluge systems used in the offshore oil- and gas platforms and simulation of deluge water interacting with fires.The effect of deluge water can be described by two separate mechanisms: 1. Direct effect on heat load to structures and vessels by water hitting objects and 2. Overall effect on flame properties (temperature, radiative heat flux density) by interaction between droplets and gases. The latter effect is specially studied in experimental work and simulation carried out during this research project and in an earlier research programme. Significant overall effect on the levels of heat fluxes to objects is observed especially in situations with mixing and recirculation of combustion products into the combustion zone, so-called enclosure effects.The use of computer model to reproduce experimental results has shown strong and weak points of current-state tood, Kamelon FireEx.The main conclusion from the literature study, the experiments carried out and the smulations is that it is substantial evidence for the statement that overall heat flux densities will be significantly reduced by using ordinary deluge systems in real offshore platform fires. Exceptions may occur locally and will depend on how water penetrates into the fire zones and on droplet characteristics.