Sec. 201 Standard for respirable dust concentration
“(i) Reports
“(1) Retrospective study
“(A) In general—Beginning on August 1, 2021, the Secretary shall conduct a retrospective study evaluating data collected using continuous personal dust monitors to determine whether to—
“(i) lower the applicable standard for respirable dust concentration to protect the health of miners;
“(ii) increase the frequency for taking samples of respirable dust concentration, using continuous personal dust monitors;
“(iii) modify the engineering controls and work practices used by mine operators to comply with the applicable standard for respirable dust concentration;
“(iv) convert samples taken for shifts that are greater than 8 hours to an 8-hour equivalent concentration to more accurately assess the conditions of miners working on longer shifts; and
“(v) lower the 100 μg/m3 standard for quartz (crystalline silica) in respirable dust to better protect miners’ health.
“(B) Completion deadline—By August 1, 2022, the Secretary shall complete the study required by subparagraph (A) and report the findings of such study to the Committee on Health, Education, Labor, and Pensions of the Senate and the Committee on Education and the Workforce of the House of Representatives.
“(2) Subsequent studies—By August 1, 2025, and every 3 years thereafter, the Secretary shall conduct a new study as described in paragraph (1)(A) and report, by not later than one year after the commencement of the study, the findings of such study to the Committee on Health, Education, Labor, and Pensions of the Senate and the Committee on Education and the Workforce of the House of Representatives.
“(3) Revised standards—If any report of the Secretary under this subsection concludes that the applicable standard for respirable dust concentration should be lowered to protect the health of miners, or that the incidence of pneumoconiosis among coal miners in the United States, as reported by the National Institute for Occupational Safety and Health, has not been reduced from such incidence prior to the implementation of the most recent applicable standard for respirable dust concentration, the Secretary shall, consistent with the requirements of this section and section 101, accordingly revise such standard and any applicable sampling or testing procedures not later than 24 months after the publication of such report of the Secretary under this subsection.”