The aim of this study is to analyze the information on workers and exposures to biological agents in Italy, collected by the National Institute for Occupational Safety and Prevention in the period 1994-2008 on the basis of a regulation. Employers are asked to identify the biological agents and to report data on employees exposed to biological hazards. Biological agents included in the system belong to risk group 3 and 4 of the European Union classification, and are grouped by family and transmission type. Data analyzed in this study regard 90 firms (28% in "Laboratory analysis clinics" economic activity) and 2,194 workers exposed to biological agents in the period 1994-2008. The most frequent biological agent reported is Salmonella typhi, while the one which counted more exposures is Mycobacterium tuberculosis. Nonetheless the incompleteness of Italian legislative framework about "exposure registers" to biological agents in the workplace, the identification of large groups of workers "at risk" can contribute to undertake epidemiological studies aimed at the prevention of occupational infection diseases.