30 CFR 90.100
§ 90.100 Respirable dust standard.
United States · 30 CFR — Mineral Resources · Status: effective
Cite this
- Citation
- 30 CFR 90.100, § 90.100 Respirable dust standard, United States, version 1 as recorded 2026-07-09, yourstate.us, https://yourstate.us/provision/134259
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Full text
The following is required as of April 14, 2025. After the 20th calendar day following receipt of notification from MSHA that a part 90 miner is employed at the mine, the operator shall continuously maintain the average concentration of respirable dust in the mine atmosphere during each shift to which the part 90 miner in the active workings of the mine is exposed, as measured with an approved sampling device and expressed in terms of an equivalent concentration, at or below 0.5 mg/m 3.
Legislative history
This is a federal regulation, adopted through agency rulemaking under the Administrative Procedure Act — not enacted by a recorded vote of Congress.