The paper discusses the computer-aided analysis and evaluation of fire safety in relation to pedestrian circulation in buildings, i.e., fire escape routes. It describes an approach employing both detailed and abstract representations. The goals of the research include: (a) the development of a pyramidal structure that links design analyses at different levels of abstraction, (b) the evaluation of abstract, normative levels of the analysis (and though these of underlying legal and professional principles) using the results of detailed, accurate simulations, and (c) the development a reliable framework for testing human behaviour in fire hazard.