Emergency medical operations have been established as an essential service in protecting people’s lives. This paper aims to describe a life environment model by which lives may continue to be protected. In the study reported here, based on the two potential hospital ship bases, two simulations were conducted and the corresponding effective spheres of the hospital ship in Tokyo Bay were visualized. By superimposing the actual sphere of the air ambulance and emergency vehicles, the characteristics required of the suggested regional cooperation among the emergency services could be analyzed for further discussion.