Various studies confirm that the evaluation of environmental quality indicators in sensitive uses such as medical buildings plays an important role in maintaining the health, satisfaction and improvement of patients. The hospital is one of the vital and sensitive parts of the city, which should be given special attention in terms of the conditions related to passive defense in order to manage risks. The main goal of the research is to evaluate the impact of environmental factors on the improvement of the accessibility of the users of treatment spaces in crisis situations with the passive defense approach. The current research is exploratory in nature and descriptive-survey in terms of data collection method. The research plan in the development of tools and preparation of expressions in three stages (1) content analysis of documents; (2) Delphi survey and (3) semiotic analysis are defined. Using questionnaire data and spss26 software and using Friedman's test to check the normality of the data to check the relationship between the variables, a statistical analysis was performed, finally with a plan analysis of two Rasoul Akram and Laleh hospitals in Tehran using Depth software. Map was used to examine the syntactic components and their relationship with the components studied in the research. According to the obtained results, the functional, physical and social indicators in accessibility are related to spatial depth and interconnectedness indicators in the space syntax method, and as a result, they affect the accessibility of space in crisis conditions in hospitals.