Federal regulations · Through 2026-08-25 · Newer source version available

30 CFR 60.2: Definitions.

Where this section sits in the code

Title 30—Mineral Resources
CHAPTER I—MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR
SUBCHAPTER M—UNIFORM MINE HEALTH REGULATIONS
PART 60—RESPIRABLE CRYSTALLINE SILICA

The following definitions apply in this part:

Action level means an airborne concentration of respirable crystalline silica of 25 micrograms per cubic meter of air (µg/m 3) for a full-shift exposure, calculated as an 8-hour time-weighted average (TWA).

Respirable crystalline silica means quartz, cristobalite, and/or tridymite contained in airborne particles that are determined to be respirable by a sampling device designed to meet the characteristics for respirable-particle-size-selective samplers that conform to the International Organization for Standardization (ISO) 7708:1995: Air Quality—Particle Size Fraction Definitions for Health-Related Sampling.

Specialist means an American Board-Certified Specialist in Pulmonary Disease or an American Board-Certified Specialist in Occupational Medicine.

Collected 2026-08-27T02:25:24Z. Source file · JSON

Browse this collection