The Code of Federal Regulations (CFR) contains the rules and regulations of Federal agencies in a codified format, similar to the U.S. Code, which codifies laws enacted by Congress. The CFR is divided into 50 titles or subject areas, each broken down into chapters, subchapters, parts, and sections. Each agency's regulations are found in one or more chapters of the CFR, depending on the function and variety of that agency's responsibilities. The Nuclear Regulatory Commission's regulations, for example, appear in Chapter 1 of Title 10.

The CFR comprises approximately 202 volumes and totals approximately 138,000 pages. Each title of the CFR is revised annually at which time all of the additions and amendments to that title which have appeared in the Federal Register over the past year are inserted into their proper places. In the meantime, changes can be found in the List of CFR Sections Affected. The CFR is now available on-line at http://www.gpo.gov/ecfr/ and at http://www.gpo.gov/nara/cfr/index.html.