MSHA - Code of Federal Regulations - 30 CFR 7.303
30 CFR § 7.303
(a) An application for approval of a motor assembly shall include a
composite drawing or drawings with the following information:
(1) Model (type), frame size, and rating of the motor
(2) Overall dimensions of the motor assembly, including
conduit box if applicable, and internal free volume.
(3) Material and quantity for each of the component parts
that form the explosion-proof enclosure or enclosures.
(4) All dimensions (including tolerances) and
specifications required to ascertain compliance with the requirements of
§7.304 of this part.
(b) All drawings shall be titled, dated, numbered, and include the
[57 FR 61193, Dec. 23, 1992]