external exposure facility MELAF MELAF (Metrological Electron beam Accelerator Facility) at PTB Braunschweig is operated for service and research in dosimetry for external beam radiotherapy, comprising a custom research electron LINAC, two commercially available medical LINACs, and a Co-60 facility. It delivers electron and photon dose rates from 0.01 Gy/min to high dose rates, with the electron energy varied continuously; the facility is used for calibrating therapy-level dosimeters and for research on detector response in clinical beam qualities. Access is by radiation protection controlled area rules under supervision of a radiation protection supervisor. Located at PTB - Physikalisch-Technische Bundesanstalt. Paul Schofield website