The Energy Policy Act of 1992 (EPAct) is an important piece of legislation for efficiency because it established minimum efficiency levels for electric motors manufactured or imported after October 1997. EPAct, which was based on NEMA standards, defined a number of terms, including what constitutes an energy-efficient motor. The DOE issued a rule that defines these motors and how manufactures must comply.

• DOE EPAct rule (PDF): Energy Efficiency Program for Certain Commercial and Industrial Equipment: Test Procedures, Labeling, and the Certification Requirements for Electric Motors. Final Rule. 10-CFR Part 431.
• Motor Provisions in the Energy Policy Act of 1992 (from ACEEE Motors book)