This work describes the production of10C(t12 = 19 s)from an enriched10B2O3target using a CTI RDS‐112 11 MeV proton cyclotron. Proton beam heating is used to raise the target to a molten state (∼ 1300 °C), enabling the activity to diffuse to the surface of the melt. An infrared thermocouple monitors the melt temperature. Helium sweep gas then transports the activity to flow‐through chemistry processing for human inhalation of10CO2for blood flow imaging with Positron Emission Tomography. The temperature‐related diffusion of activity out of the white‐hot molten glass target is discussed. © 2003 American Institute of Physics