(a) The operator shall take five valid representative dust samples for each part 90 miner within 15 calendar days after:   (1) The 20-day period specified for each part 90 miner in §90.100; and   (2) Implementing any transfer after the 20th calendar day following receipt of notification from MSHA that a part 90 miner is employed at the mine.

(b) Noncompliance with the applicable standard shall be determined in accordance with §90.207(d) of this part.

(c) Upon issuance of a citation for a violation of the applicable standard, the operator shall comply with §90.207(f) of this part.