The radiation response of spores of Bacillus pumilus was examined for irradiation with 5-7 MeV X-ray at commercial sterilization facilities. The response was found to be the same as that for irradiation with cobalt 60 photons, 10 MeV electrons and low energy electrons at 100 and 80 keV. (C) 2014 Elsevier Ltd. All rights reserved.