title: Radiation from the uranium collimators of the Varian 4-MeV accelerator.
abstract: The uranium collimator of the Varian 4-MeV accelerator produces a dose rate of 100 mR/h near the collimator opening. It can be decreased to 4% by a 6-mm Lucite shield at the level of the collimator opening. A better solution is a lead glass-mylar (EM) shield which decreases the uranium radiation to less than 3% and also provides better skin sparing during treatment than the open collimator.
mesh_terms: D010315:Particle Accelerators; D011829:Radiation Dosage; D011835:Radiation Protection; D014501:Uranium
chemical_list: D014501:Uranium