The Food and Drug Administration (FDA) is amending the food additive regulations to provide for the safe use of a 4.5 kilogray (kGy) maximum absorbed dose of ionizing radiation to treat unrefrigerated (as well as refrigerated) uncooked meat, meat byproducts, and certain meat food products to reduce levels of foodborne pathogens and extend shelf life. This action is in response to a petition filed by the U.S. Department of Agriculture, Food Safety and Inspection Service (USDA/FSIS).