Bacillus pumilus is a Gram-positive, aerobic, spore-forming Bacillus. Bacillus pumilus spores generally show high resistance to environmental stresses, including UV light exposure, desiccation, and the presence of oxidizers such as hydrogen peroxide. Bacillus pumilus may be utilized (as a biological indicator) to monitor Gamma, Electron Beam (E-beam), or X-ray radiation sterilization processes.