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30 U.S. Code § 955 - State laws

(a)
No State law in effect on December 30, 1969 or which may become effective thereafter shall be superseded by any provision of this chapter or order issued or any mandatory health or safety standard, except insofar as such State law is in conflict with this chapter or with any order issued or any mandatory health or safety standard.
(b)
The provisions of any State law or regulation in effect upon the operative date of this chapter, or which may become effective thereafter, which provide for more stringent health and safety standards applicable to coal or other mines than do the provisions of this chapter or any order issued or any mandatory health or safety standard shall not thereby be construed or held to be in conflict with this chapter. The provisions of any State law or regulation in effect on December 30, 1969, or which may become effective thereafter, which provide for health and safety standards applicable to coal or other mines for which no provision is contained in this chapter or in any order issued or any mandatory health or safety standard, shall not be held to be in conflict with this chapter.
Editorial Notes
References in Text

This chapter, referred to in text, was in the original “this Act”, meaning Pub. L. 91–173, Dec. 30, 1969, 83 Stat. 742, known as the Federal Mine Safety and Health Act of 1977, which is classified principally to this chapter. For complete classification of this Act to the Code, see Short Title note set out under section 801 of this title and Tables.

For the operative date of this chapter, referred to in subsec. (b), see section 509 of Pub. L. 91–173, set out as an Effective Date note under section 801 of this title.

Amendments

1977—Subsec. (b). Pub. L. 95–164 inserted reference to mines other than coal mines.

Statutory Notes and Related Subsidiaries
Effective Date of 1977 Amendment

Amendment by Pub. L. 95–164 effective 120 days after Nov. 9, 1977, except as otherwise provided, see section 307 of Pub. L. 95–164, set out as a note under section 801 of this title.