30 CFR § 57.4532
Blacksmith shops.
Blacksmith shops located on the surface shall be--
(a) At least 100 feet from fan installations used for intake air and
mine openings;
(b) Equipped with exhaust vents over the forge and ventilated to
prevent the accumulation of the products of combustion; and
(c) Inspected for smoldering fires at the end of each shift.
