“…As heavy ion therapy has been put into practice, more people have paid attention to the environmental impact caused by the radiation of heavy ion accelerator induced radioactivity. However, many of these reports were only very recently published [9,10]. HIMM includes an ion source, a low energy beam transport line, an injector cyclotron, a middle energy beam transport line, a synchrotron (main accelerator), a high energy beam transport line, and four treatment rooms (Fig.…”