#### § 70.209T Quarterly sampling; designated areas.

###### Cross Reference

Link to an amendment published at [89 FR 28476](https://www.federalregister.gov/citation/89-FR-28476), Apr. 18, 2024.

As of April 14, 2025:

(a) The operator shall sample quarterly each designated area (DA) on consecutive production shifts until five valid representative samples are taken. The quarterly periods are:

(1) January 1-March 31

(2) April 1-June 30

(3) July 1-September 30

(4) October 1-December 31.

(b) [Reserved]

(c) When a valid representative sample taken in accordance with this section meets or exceeds the ECV in table 1 to this section that corresponds to the particular sampling device used, the operator shall:

(1) Make approved respiratory equipment available to affected miners in accordance with [§ 72.700 of this chapter](/on/2024-09-16/title-30/section-72.700);

(2) Immediately take corrective action to lower the concentration of respirable dust to at or below the respirable dust 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.

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

(1) Two or more valid representative samples meet or exceed the ECV in table 1 to this section that corresponds to the particular sampling device used; or

(2) The average for all valid representative samples meets or exceeds the ECV in table 1 to this section that corresponds to the particular sampling device used.

(e) Unless otherwise directed by the District Manager, upon issuance of a citation for a violation of the standard, [paragraph (a)](/on/2024-09-16/title-30/section-70.209T#p-70.209T(a)) of this section shall not apply to that DA until the violation is abated and the citation is terminated in accordance with [paragraphs (e)](/on/2024-09-16/title-30/section-70.209T#p-70.209T(e)) and [(f)](/on/2024-09-16/title-30/section-70.209T#p-70.209T(f)) of this section.

(f) Upon issuance of a citation for a violation of the 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](/on/2024-09-16/title-30/section-72.700);

(2) Immediately take corrective action to lower the concentration of respirable coal mine dust to at or below the 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.

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

(1) Each of the five valid representative samples is at or below the 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.

Table 1 to [§ 70.209T](/on/2024-09-16/title-30/section-70.209T)—Excessive Concentration Values (ECV) Based on a Single Sample, Two Samples, or the Average of Five or Fifteen Full-Shift CMDPSU/CPDM Concentration Measurements

| Section | Samples | ECV (mg/m3) | |
| --- | --- | --- | --- |
| CMDPSU | CPDM |
| 70.209 (c) | 70.100(a)—Single sample | 1.79 | 1.70 |
| | 70.100(b)—Single sample | 0.74 | 0.57 |
| 70.209(d)(1) | 70.100(a)—2 or more samples | 1.79 | 1.70 |
| | 70.100(b)—2 or more samples | 0.74 | 0.57 |
| 70.209(d)(2) | 70.100(a)—5 sample average | 1.63 | 1.59 |
| | 70.100(b)—5 sample average | 0.61 | 0.53 |
| 70.209(d)(2) | 70.100(a)—15 sample average | 1.58 | 1.56 |
| | 70.100(b)—15 sample average | 0.57 | 0.52 |
| 70.209(g)(1) | 70.100(a)—Each of 5 samples | 1.79 | 1.70 |
| | 70.100(b)—Each of 5 samples | 0.74 | 0.57 |

[[89 FR 28475](https://www.federalregister.gov/citation/89-FR-28475), Apr. 18, 2024]