30 CFR § 57.22232 - Actions at 0.5 percent methane (I-B, II-A, II-B, IV, V-B, and VI mines).

---
identifier: "/us/cfr/t30/s57.22232"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "30 CFR § 57.22232 - Actions at 0.5 percent methane (I-B, II-A, II-B, IV, V-B, and VI mines)."
title_number: 30
title_name: "Mineral Resources"
section_number: "57.22232"
section_name: "Actions at 0.5 percent methane (I-B, II-A, II-B, IV, V-B, and VI mines)."
chapter_name: "MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR"
subchapter_number: "K"
subchapter_name: "METAL AND NONMETAL MINE SAFETY AND HEALTH"
part_number: "57"
part_name: "SAFETY AND HEALTH STANDARDS—UNDERGROUND METAL AND NONMETAL MINES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "30 U.S.C. 811."
regulatory_source: "50 FR 4082, Jan. 29, 1985, unless otherwise noted."
cfr_part: "57"
---


# 57.22232 Actions at 0.5 percent methane (I-B, II-A, II-B, IV, V-B, and VI mines).

If methane reaches 0.5 percent in the mine atmosphere, ventilation changes shall be made to reduce the level of methane. Until methane is reduced to less than 0.5 percent, electrical power shall be deenergized in affected areas, except power to monitoring equipment determined by MSHA to be intrinsically safe under 30 CFR part 18. Diesel equipment shall be shut off or immediately removed from the area and no other work shall be permitted in affected areas.

[52 FR 24941, July 1, 1987; 52 FR 27903, July 24, 1987]