Experiments on the radiosensitivity of individual microorganisms showed that a bacterial species (Bacillus subtilis) was more sensitive to Co⁶⁰ gamma radiation than either of two fungal species (Coniophera cerebella, Merulius lachrymans). Doses sufficient for sterilizing in those three cases were 320, 960 and 720 krad respectively. Irradiation of contaminated wood samples at 2.5 Mrad or greater gave complete sterilization. Regarding insect disinfection, not all larvae were destroyed at 60 krad, but 100 krad was lethal to nearly all species. Various paint media and pigments were tested for visible change under various doses; the results are tabulated. Changes were observed in most media and some pigments at 4.0 Mrad.