For the operative date of this subchapter, referred to in subsecs. (b)(1) and (d), see section 509 of Pub. L. 91–173, set out as a note under section 801 of this title.

This chapter, referred to in subsec. (h), 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.

1977—Subsec. (e). Pub. L. 95–164 substituted a general reference to an “approved device” used to measure the average concentration of respirable dust for provisions which had referred to a specific device known as an “MRE instrument”.

“Secretary of Health and Human Services” substituted for “Secretary of Health, Education, and Welfare” in subsecs. (a), (d) to (f), and (h) pursuant to section 509(b) of Pub. L. 96–88 which is classified to section 3508(b) of Title 20, Education.

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

Section operative six months after Dec. 30, 1969, except to the extent an earlier date is specifically provided for in Pub. L. 91–173, see section 509 of Pub. L. 91–173, set out as a note under section 801 of this title.