The present paper describes the initial steps to the development of a risk assessment methodology to quantify the life safety risk for people present in buildings in the context of the creation of a fire safety design. The current situation in countries (e.g. Belgium, etc.) with prescriptive based legislation is discussed from which two fundamental problems are derived. This is lack of quality of quantification of performance based designs and no quantitative comparison between the former and prescriptive concepts. Regarding these problems, a quantitative risk assessment approach for different types of buildings with complex geometries is suggested. The purpose is to develop a method which can verify the safety level of the designed buildin...