This document is one of a series providing support for regulations issued by the U.S. Environmental Protection Agency (EPA) under Subtitle C of the Resource Conservation and Recovery Act (RCRA). The regulations represent the initial effort for nationwide control of hazardous waste from point of generation, through transportation, treatment, and storage, to point of ultimate disposal. This document explains the basis for regulations concerning discarded commercial products. Commercial chemical products or manufacturing chemical intermediates are divided into two categories: those which are acutely hazardous and subject to stringent exclusion levels; and those which are hazardous and which are regulated in the same manner as other hazardous wastes. These regulations concern commercial chemical products and associated off-specification chemical products, spill cleanup residues, and debris. For acutely hazardous chemical, the regulations also cover containers and inner liners which contained the acutely hazardous chemicals.