30 CFR 57.22221
§ 57.22221 Overcast and undercast construction (I-A, II-A, III, and V-A mines).
United States · 30 CFR — Mineral Resources · Status: effective
Cite this
- Citation
- 30 CFR 57.22221, § 57.22221 Overcast and undercast construction (I-A, II-A, III, and V-A mines), United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/133247
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Full text
Overcasts and undercasts shall be—
(a) Of substantial construction;
(b)(1) Constructed of noncombustible materials; or
(2) Where constructed of combustible materials, the outside surfaces shall be coated with at least one inch of construction plaster containing perlite and gypsum; at least one inch of expanded vermiculite, Portland cement and limestone; or other coatings with equivalent fire resistance;
(c) Kept clear of obstructions.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.