CFR /  Title 30  /  Part 57  /  Sec. 57.22222 Ventilation materials (I-A, I-B, I-C, II-A, III, V-A,

Brattice cloth and ventilation tubing shall be approved by MSHA in accordance with 30 CFR part 7, or shall bear a BC or VT acceptance number issued by the MSHA Approval and Certification Center. [54 FR 30508, July 20, 1989]