30 CFR § 71.100 - Respirable dust standard.

---
identifier: "/us/cfr/t30/s71.100"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "30 CFR § 71.100 - Respirable dust standard."
title_number: 30
title_name: "Mineral Resources"
section_number: "71.100"
section_name: "Respirable dust standard."
chapter_name: "MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR"
subchapter_number: "O"
subchapter_name: "COAL MINE SAFETY AND HEALTH"
part_number: "71"
part_name: "MANDATORY HEALTH STANDARDS—SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL 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, 813(h), 957."
regulatory_source: "37 FR 6368, Mar. 28, 1972, unless otherwise noted."
cfr_part: "71"
---


# 71.100 Respirable dust standard.

Each operator shall continuously maintain the average concentration of respirable dust in the mine atmosphere during each shift to which each miner in the active workings of each mine is exposed, as measured with an approved sampling device and expressed in terms of an equivalent concentration, at or below:

(a) 2.0 milligrams of respirable dust per cubic meter of air (mg/m
<sup>3</sup>).

(b) 1.5 mg/m
<sup>3</sup> as of August 1, 2016.