In a study made for the U. S. Army Quartermaster Corps, all of the known types of radiation sources of sufficient size to be of interest in large scale radiation processing were compared. The sources considered are spent fuel elements from a power reactor, fission product gases from a fluid-fuel reactor, separated fission product Cs137, reactor-coolant Na24, neutron-activated In116m charged particle accelerators and x-rays. This paper summarizes the results of the study.