The aim of our study is evaluating occupational exposure in a factory named "Poligrafico Zecca dello Stato" in Foggia. The workers had a occupational disease "chlorine related parodontal disease" indemnified by INAIL (Italian Occupational Assurance). The study demonstrated the workers have been indemnified worked as engineer, drying and electrolysis process employed. The study showed that the workers indemnified without legal action were different in respect of workers that take legal action, because the last showed, paradoxically, a chlorine occupational exposure. The explanation of this paradox might be the production cycle non acknowledge by operators.