Existence of security in urban environments is one of the basic requirements for the quality of life of citizens. District 12 of Tehran, as one of the main entrances to the city in the south of Tehran, accepting all kinds of ethnicities and immigrants to live in this area, the existence of drug addicts, beggars, sleeping cartons, working children, etc., a suitable hospital It has been created to create insecure and abnormal spaces and increase the amount of crime in this area. The purpose of this study was to analyze the viability of worn-out residential structures in District 12 of Tehran with an emphasis on crime prevention and security.

The present study is of "applied" type and "quantitative-survey" method and to collect the descriptive part of the research from studies and library documents related to the research topic and for the analytical part of the research using the survey method and a researcher-made questionnaire. Has been. The statistical population of this study consisted of 240,909 residents of the 12th district of Tehran. The statistical sample size was estimated to be 384 using the Cochran's formula. Data collection tool in this study was a researcher-made questionnaire that was randomly distributed and collected among the sample size. To determine the validity of the questionnaire, the KMO measure was used in the form of factor analysis test, the validity of which was evaluated as 0.83 and at an appropriate level. Cronbach's alpha coefficient test was used to determine the reliability of the questionnaire.

Security is the background of a healthy society and the sense of security is a platform for the development of human societies, and the happiness of a society depends on the preservation and survival of security and the sense of security.

Urban spaces, as a platform for citizens' lives and activities, should be able to provide a safe, healthy, sustainable and attractive environment for all people, considering the similarities and differences between people and age and social groups.and respond appropriately to the needs of all social strata and respond to the minimum needs. In this sense, the existence of security in urban environments is considered one of the requirements of urban bio-acceptability. The criteria and indicators of bio-acceptability are different according to different time and place conditions.The experiences of different countries in the field of bio-acceptability show that the emphasized indicators of bio-acceptability are different in developing and developed countries.Nowadays, due to the spread of urbanization and the prevalence of various crimes and social insecurities in cities, it is necessary to study the subject of security, factors affecting it, and ways to strengthen security in cities in all developed countries.In this context, theories such as the theory of defensible spaces, crime prevention through environmental design and environmental criminology have been obtained. He prevented or reduced crime and delinquency in the urban environment.And in this order, improve the level of security of the citizens.

It can be done with proper urban planning and fair distribution of urban facilities and creation of safe spaces for citizens to talk and spend their free time in it and to make the city a neighborhood and prevent regionalism in localities from disappearing and after that to move up and move up and down. Taking care of the environment of his neighborhood and interfering in the improvement of the conditions in the neighborhood created an environment with high security and peace and far from violence and crime.

In other words, due to its special characteristics from the point of view of activity and body, the worn-out tissues have a suitable platform for the growth and formation of malignant places. In this regard, in this research, by using scientific theories and field surveys, the effective components on preventing crimes and providing security in the worn-out fabric of the 12th district of Tehran were investigated, and the result was as follows.

among the factors affecting the security situation, the management index and maintenance of space have the greatest impact on the conditions prevailing on the eroded fabric of district 12 of tehran. other indicators related to physical security, space image, natural monitoring and line of vision, access control in order of conditions governing the security of eroded fabric in district 12 of tehran.