The world preocupation with the dissemination of "AIDS" virus obliged us to elaborate specific techniques procedures of prevention which were adapted in a Surgical Center with 18 operating rooms on a university hospital with 900 beds. The period of study lasted five months. The methodology used was studies on date obtained by blood examination from patients who had urgent surgery without previous history of the disease, during a period of twenty days, in order to find out contamined persons. Hundred cases were observed. Finaly, through the results we conclud hat it is necessary for the health personnels to be aware about the importance of using suitable techniques procedures in order to prevent "AIDS".