70.208—Bimonthly sampling; designated areas.
(a)
Each operator shall take one valid respirable dust sample from each designated area on a production shift during each bimonthly period beginning with the bimonthly period of December 1, 1980. 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 (Respirable dust standard when quartz is present), respirable dust sampling of designated areas shall begin on the first production shift during the next bimonthly period following notification of such change from MSHA.
(c)
Upon notification from MSHA that any respirable dust sample taken from a designated area to meet the requirements of paragraph (a) or (b) of this section exceeds the applicable standard in § 70.100 (Respirable dust standards) or § 70.101 (Respirable dust standard when quartz is present), the operator shall take five valid respirable dust samples from that designated area 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)
Upon issuance of a citation for a violation of § 70.100 (Respirable dust standards) or § 70.101 (Respirable dust standard when quartz is present) involving a designated area, paragraphs (a), (b) and (c) of this section shall not apply to that designated area until the violation is abated in accordance with § 70.201(d) (Sampling; general requirements).
(e)
Designated area samples shall be collected at locations to measure respirable dust generation sources in the active workings. The approved mine ventilation plan contents required by § 75.371(t) of this chapter shall show the specific locations where designated area samples will be collected. Each designated area will be assigned a four-digit identification number by MSHA.
(f)
MSHA approval of the operator's ventilation system and methane and dust control plan may be revoked based on samples taken by MSHA or in accordance with this part 70.