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Statute

Clean Air Act § 209 (42 U.S.C. § 7543) — California waiver authority

United States Code

Overview

Section 209 preempts state motor vehicle emission standards but allows California to receive a waiver of preemption, which other states may then adopt under § 177.

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Operative language

Short paraphrases of the operative text. Read the full section at the source.

  • 42 U.S.C. § 7543(b)(1) · Open source

    The Administrator shall waive the general preemption of state motor-vehicle emission standards for any state which had adopted such standards prior to March 30, 1966 (in practice, California), unless the Administrator finds specific statutory disqualifiers.

    Establishes: The California waiver mechanism. Other states may adopt California's standards under § 177.

    Plain English: Congress preempted state emissions rules but carved out California. That carve-out is how state-level diesel and zero-emission mandates spread. A federal repeal that ignores § 209 leaves waiver-state mandates intact.