The X-ray diagnostic is one of the main diagnosis tools in medicine and its role, in public health, depends on the quality of the exams, the regulatory responsibility fits, mainly, in the National System of Sanitary Surveillance. With this perspective, it was developed a mathematical evaluation model of potential risks in radiodiagnostic and, through its use in the Brazilian health services of Bahia state, with the analysis of the situation found and its determinants. With that model, 94 procedures were evaluated in 38 Bahia state radiodiagnostic services. The study showed that 5.3% of the services had all of the procedures in level of acceptable potential risk. 23.7% showed, at least, one procedure with level of tolerable potential risk and 71% showed, at least, one procedure with a level of unacceptable potential risk. The analyses shows that the main determinants of the encountered situation are the deficient inspection by the sanitary surveillance system of the health services and of the industrial sector, the absence of basics of radiological protection in the curriculum of medicine courses and the fragility of practices control, by the respective professional council.