The aim was to identify the processing of potentially infectious residues and of piercing and cutting residues at hemotherapy units and their possible relation with workers' health. No service presented a structured plan for managing health service residues or for the occupational safety program. We found an occupational accident rate of 32.82% and that 9.16% of the workers did not have a complete plan of vaccination against hepatitis B. In-service training in handling residues and in occupational health are not standardized. The rate of serum conversion for HBV and HCV after occupational exposure was 11.63%. We concluded that the processing of potentially infectious residues and of piercing and cutting residues at the examined hemotherapy units has exposed workers to the acquisition of infectious diseases.