A Radiation Sterilization Validation is defined as the dose of radiation necessary to produce a 90% reduction in a number of indicator microbial cells, which determines the appropriate radiation sterilization dose for a product that requires a sterile label claim. It depends on many factors including temperature, moisture, organism species, chemical environment, or physical surface on which indicator microorganism is attached. Bacillus Pumilus spores are USP choice as a biological indicator for radiation sterilization. This includes bioburden testing, the bioburden recovery efficiency test, a radiation dose verification, a test of sterility, and bacteriostasis or fungistatic testing.