30 CFR §57.22209

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗

Electric auxiliary fans shall be approved by MSHA under the applicable requirements of 30 CFR part 18. Tests for methane shall be made at electric auxiliary fans before they are started. Such fans shall not be operated when air passing over or through them contains 0.5 percent or more methane.