Section was formerly classified to section 1857f–6a of this title.

A prior section 209 of act July 14, 1955, as added Nov. 21, 1967, Pub. L. 90–148, § 2, 81 Stat. 502, was renumbered section 210 by Pub. L. 91–604 and is classified to section 7544 of this title.

Another prior section 209 of act July 14, 1955, ch. 360, title II, as added Oct. 20, 1965, Pub. L. 89–272, title I, § 101(8), 79 Stat. 995, related to appropriations for the fiscal years ending June 30, 1966, 1967, 1968, and 1969, and was classified to section 1857f–8 of this title, prior to repeal by Pub. L. 89–675, § 2(b), Oct. 15, 1966, 80 Stat. 954.

1990—Subsec. (e). Pub. L. 101–549 added subsec. (e).

1977—Subsec. (b). Pub. L. 95–95, § 207, designated existing provisions as par. (1), substituted “March 30, 1966, if the State determines that the State standards will be, in the aggregate, at least as protective of public health and welfare as applicable Federal standards” for “March 30, 1966, unless he finds that such State does not require standards more stringent than applicable Federal standards to meet compelling the extraordinary conditions or that such State standards and accompanying enforcement procedures are not consistent with section 7521(a) of this title”, added subpars. (A), (B), and (C), and added pars. (2) and (3).

Subsecs. (c), (d). Pub. L. 95–95, § 221, added subsec. (c) and redesignated former subsec. (c) as (d).

1970—Subsec. (a). Pub. L. 91–604, § 11(a)(2)(A), substituted “part” for “subchapter”.

Subsec. (b). Pub. L. 91–604, § 15(c)(2), substituted “Administrator” for “Secretary”.

Subsec. (c). Pub. L. 91–604, § 11(a)(2)(A), substituted “part” for “subchapter”.

Amendment by Pub. L. 95–95 effective Aug. 7, 1977, except as otherwise expressly provided, see section 406(d) of Pub. L. 95–95, set out as a note under section 7401 of this title.

All rules, regulations, orders, determinations, contracts, certifications, authorizations, delegations, or other actions duly issued, made, or taken by or pursuant to act July 14, 1955, the Clean Air Act, as in effect immediately prior to the date of enactment of Pub. L. 95–95 [Aug. 7, 1977] to continue in full force and effect until modified or rescinded in accordance with act July 14, 1955, as amended by Pub. L. 95–95 [this chapter], see section 406(b) of Pub. L. 95–95, set out as an Effective Date of 1977 Amendment note under section 7401 of this title.