In the context of "direct" or "indirect" patient care, residual risk of biological agents exposure constitute a hazard for health and safety, that cross and affects all health care workers. For the development and implementation of effective "prevention and control" actions, even against nosocomial infections, it is nevertheless most important to acquire objective information on the level of risk perception demonstrated by relevant staff for assistance. The aim of this contribution was therefore to study the attitudes and behaviours of health sector workers in relation to the specific "biological agents risk". The survey was carried out in a italian hospital, and 25 in the study adhered responsible for the safety and 219 nurses, identified as exposed to biological agents (244 subjects), who were given a specially designed questionnaire. The results of the study, which will be described in detail, has helped to identify critical issues related to the management of "biological agents risk", and at the same time to set up a program for improvement of prevention and protection, aimed at a substantial reduction of the same risk factor.