Classification of low-level radioactive waste (LLW) according to its radiological hazard. The classes include Class A, B, and C, with Class A being the least hazardous and accounting for 96 percent of LLW. As the waste class and hazard increase, the regulations established by the NRC require progressively greater controls to protect the health and safety of the public and the environment. For the specific regulations, see Title 10, Section 61. 55, of the Code of Federal Regulations (10 CFR 61. 55), "Waste Classification. "