Until January 31, 2016:

(a) Each operator shall take one valid representative sample from each designated area (DA) on a production shift during each bimonthly period. The bimonthly periods are:

February 1-March 31

April 1-May 31

June 1-July 31

August 1-September 30

October 1-November 30

December 1-January 31.

(b) When the respirable dust standard is changed in accordance with §70.101, the new applicable standard shall become effective 7 calendar days after the date of the notification of the change by MSHA.

(c) Upon notification from MSHA that any valid sample taken from a DA to meet the requirements of paragraph (a) of this section exceeds the applicable standard, the operator shall take five valid representative samples from that DA within 15 calendar days. The operator shall begin such sampling on the first day on which there is a production shift following the day of receipt of notification.

(d) When a valid representative sample taken in accordance with this section meets or exceeds the ECV in Table 70-1 that corresponds to the applicable standard and particular sampling device used, the operator shall:

(1) Make approved respiratory equipment available to affected miners in accordance with §72.700 of this chapter;

(2) Immediately take corrective action to lower the concentration of respirable coal mine dust to at or below the applicable standard; and

(3) Make a record of the corrective actions taken. The record shall be certified by the mine foreman or equivalent mine official, no later than the end of the mine foreman's or equivalent official's next regularly scheduled working shift. The record shall be made in a secure book that is not susceptible to alteration or electronically in a computer system so as to be secure and not susceptible to alteration. Such records shall be retained at a surface location at the mine for at least 1 year and shall be made available for inspection by authorized representatives of the Secretary and the representative of miners.

(e) Noncompliance with the applicable standard is demonstrated during the sampling period when:

(1) Two or more valid representative samples meet or exceed the ECV in Table 70-1 that corresponds to the applicable standard and the particular sampling device used; or

(2) The average for all valid representative samples meets or exceeds the ECV in Table 70-2 that corresponds to the applicable standard and the particular sampling device used.

(f) Unless otherwise directed by the District Manager, upon issuance of a citation for a violation of the applicable standard, paragraph (a) of this section shall not apply to that DA until the violation is abated and the citation is terminated in accordance with paragraphs (g) and (h) of this section.

(g) Upon issuance of a citation for violation of the applicable standard, the operator shall take the following actions sequentially:

(1) Make approved respiratory equipment available to affected miners in accordance with §72.700 of this chapter;

(2) Immediately take corrective action to lower the concentration of respirable coal mine dust to at or below the applicable standard; and

(3) Make a record of the corrective actions taken. The record shall be certified by the mine foreman or equivalent mine official, no later than the end of the mine foreman's or equivalent official's next regularly scheduled working shift. The record shall be made in a secure book that is not susceptible to alteration or electronically in a computer system so as to be secure and not susceptible to alteration. Such records shall be retained at a surface location at the mine for at least 1 year and shall be made available for inspection by authorized representatives of the Secretary and the representative of miners.

(4) Begin sampling, within 8 calendar days after the date the citation is issued, the environment of the affected DA on consecutive normal production shifts until five valid representative samples are taken.

(h) A citation for a violation of the applicable standard shall be terminated by MSHA when:

(1) Each of the five valid representative samples is at or below the applicable standard; and

(2) The operator has submitted to the District Manager revised dust control parameters as part of the mine ventilation plan applicable to the DA in the citation, and the changes have been approved by the District Manager. The revised parameters shall reflect the control measures used by the operator to abate the violation.