An official website of the United States government
Coal Dust Particle Size Surveys
August 2009
NIOSH Docket Number 174
The National Institute for Occupational Safety and Health (NIOSH) and MSHA conducted a joint survey to determine the range of coal particle sizes found in dust samples collected from intake and return airways of U.S. coal mines. Results from this survey show that the coal dust found in mines today is much finer than in mines of the 1920s, presumably due to increased automation and a greater reliance on mining machinery.
Given the results of the recent coal dust particle size survey and large-scale explosion tests, NIOSH recommends a new standard of 80% total incombustible content be required in the intake airways of bituminous coal mines.
Notice of draft publication available for public comment; 74 FR 42317; 8/21/09 [PDF – 2,303 KB]
Draft NIOSH document, “Recent Coal Dust Particle Size Surveys and the Implications for Mine Explosions;” 10/1/09 [PDF – 33,636 KB]
NIOSH responses to comments received on document; 5/1/10 [PDF – 8,721 KB]
Submissions
Submission to the docket from Leeming (Health and Safety Executive (UK)) – 8/14/09 [PDF – 467 KB]
Submission to the docket from Parsons (United Mine Workers of America) – 9/15/09 [PDF – 8,284 KB]
Peer Review
Title: Recommendations for a New Rock Dusting Standard to Prevent Coal Dust Explosions in Intake Airways
Previous Title: Recent Coal Dust Particle Size Surveys and the Implications for Mine Explosions
Subject: This report gives the results of recent coal dust particle size surveys and large-scale explosion tests and how this data impacts rock dusting requirements for underground coal mines.
Purpose: This document will show that the current rock dusting regulation in 30 CFR Pat 75.403 is not sufficient for protecting the mine worker from dust explosions.
Timing of Review: July 2009
Primary Disciplines or Expertise Needed for Review: Physics, mining health and safety, mine explosion research, combustion research
Type of Review: Individual Reviews
Number of Reviewers: 5
Reviewers Selected by: NIOSH
Public Nominations Requested for Reviewers: No
Opportunities for the Public to Comment: Yes
Cross-Clearance Agencies: None
Type of Dissemination: Influential
Peer Reviewers Provided with Public Comments Before Their Review: No
Peer Reviewers:
Larry Grayson, PhD
Dept. of Mining Eng., Penn State University
Areas of Expertise: Mine health and safety
Recommended by: NIOSH
Jan DuPlessis, PhD
Goldfields, Ltd., South Africa
Areas of Expertise: Mine explosion research
Recommended by: NIOSH
Marty Hertzberg, PhD
Consultant
Areas of Expertise: Mine explosion research
Recommended by: NIOSH
Paul Amyotte, PhD
Dept. of Chemical Eng., Dalhousie University, Nova Scotia, Canada
Areas of Expertise: Explosion research
Recommended by: NIOSH
Paul Harrison, PhD
Director, SIMTARS Australia
Areas of Expertise: Mine safety research
Recommended by: NIOSH
Charge to Peer Reviewers:
NIOSH is currently assembling a document titled “Recent Coal Dust Particle Size Surveys and the Implications for Mine Explosions.” The authors are Ken Cashdollar, Mike Sapko, Eric Weiss, and others. As you know, NIOSH documents go through an internal and external review process. We anticipate that this document will be influential as it will likely impact rock dusting requirements for U.S. underground coal mines. Can you provide one of these external reviews? The document is currently ready for review. Please let me know if you can help us out on this. Thanks for your assistance.