30 CFR § 33.3
By appointment, applicants or their representatives may visit the
U.S. Department of Labor, Mine Safety and Health Administration,
Approval and Certification Center, 765 Technology Drive, Triadelphia,
WV 26059, to discuss with MSHA personnel proposed designs of equipment
to be submitted in accordance with the regulations of this part. No charge is made for such consultation and no written report thereof will be made to the applicant.