Descriptive study, with qualitative approach, in order to understand the perception of the nursing staff regarding the safety of elderly patients in the administration of iodinated contrast media, conducted at the diagnostic imaging centers of two private hospitals, located in Brasília, Federal District, Brazil. Data were collected by technical interview of eleven participants, between July and August 2012. The analysis and processing of the data were made by means of the method of content analysis, bringing out the safety category of the elderly in the realization of cardiac computed tomography - coronarian angiography. The nursing staff understood that the safety of the elderly in the exam is associated with the ability to assess risks for adverse events related to the administration of the radiopharmaceutical, in which processes, technologies and human interactions intertwine, implying in safe practices.