ABSTRACT This thesis deals with the simulation of fires in various environments, using real geometry. If we want to understand the specific fire behavior is not enough to study the simulation using actual geometry. For geometry apply a laser scanner. As the amount of points earned over the scanner is studied as getting the geometry of the point cloud and to optimally transfer simulation program. This is addressed: - An analysis and comparison of two methods to obtain parameters describing the geometry of point clouds obtained from laser scanner. This has been done to apply software algorithms on data extracted from a laser scanner, analyze the results and generate a file to begin the computer fire simulation. - The study of a real event in the city of Valencia with trapped fire service members, compared with the virtual simulation, allows a scientific better understanding the fire development. - We apply also in forest environment comparing the results obtained by simulation with real geometry with the real case. The study of the phenomena that occur in forest fires and their complexity not come to understand by the staff involved in the extinction has led in some of the examples studied catastrophic results. - Another different environment that can be applied in simulation studies is over fire in tunnels. The study is used to determine the floor influence over a tunnel fire. We get conclusions over provided energy with bituminous pavement or concrete pavement. The research analyzes the current situation to understand the scale of the problem. This followed by a study on how to optimize the geometry obtained by laser scanner. It works with the point cloud and cleans up the parameters calculation slowing. Given below is a computer program to enter the data extracted from the laser scanner to the computer program that allows us to perform studies of fires. The methodology allows continuing the simulation studies and compared with real fires. It concludes with a study analyzing incidents that remain today and that should be for future research professionals dedicated to this topic.