Combustible Dust

Control of Combustible Dust

“DOL/OSHA  RIN: 1218-AC41  Publication ID: Spring 2013

Title: Combustible Dust

OSHA has commenced rulemaking to develop a combustible dust standard for general industry. The U.S. Chemical Safety Board (CSB) completed a study of combustible dust hazards in late 2006, which identified 281 combustible dust incidents between 1980 and 2005 that killed 119 workers and injured another 718. Based on these findings, the CSB recommended the Agency pursue a rulemaking on this issue. OSHA has previously addressed aspects of this risk. For example, on July 31, 2005, OSHA published the Safety and Health Information Bulletin, “Combustible Dust in Industry: Preventing and Mitigating the Effects of Fire and Explosions.” Additionally, OSHA implemented a Combustible Dust National Emphasis Program (NEP) March 11, 2008. However, the Agency does not have a comprehensive standard that addresses combustible dust hazards. OSHA will use the information gathered from the NEP to assist in the development of this rule.”   Source: OSHA –

OSHA is currently enforcing dust control by the General Duty Clause and consensus standards.  For a General Duty Citation the following guidance is followed:

Evaluation of Potential 5(a)(1) situations:

Employer failed to keep workplace free of hazards to which employees of that employer were exposed.

  • Must involve a serious hazard and employee exposure;
  • Does not specify a particular abatement method – only that the employer keeps the workplace free of serious hazards by any feasible and effective means;
  • The hazard must be reasonably foreseeable.

The hazard was recognized:

  •  Industry recognition;
  • Employer recognition;
  • Common-sense recognition.

The hazard caused or was likely to cause death or serious physical harm.
Feasible means to correct the hazard were available.

OSHA also has a compliance directive, CPL 03-00-008 – Combustible Dust National Emphasis Program (Reissued) is the basis for enforcement.

Appendix D-2 in this CPL lists industries that may have Potential for Combustible Dust Explosions/Fires and this includes sewerage treatment facilities.

The National Fire Protection Association has published NFPA 654 – Standard for the Prevention of Fire and Dust Explosions from the Manufacturing, Processing, and Handling of Combustible Particulate Solids 2006 Edition that contains procedures for minimizing the risk of a combustible dust explosion. Much of the standard deals with structural or construction issues, but there are some that fall under safety and health. These are procedures and policies that employers can develop to protect workers in sites where the possibility of dust accumulation may present a risk of combustion.

  • General Requirements – Fire and explosion safety provisions shall be based on a process hazard analysis of the facility, the process and the associated fire and explosion hazards.
  • Performance-Based Design options consist of Occupant life Safety and Mitigation of fire spread and explosions through building design and housekeeping and inventory storage..
  • Fugitive dust control regular cleaning frequencies shall be established for walls, floors and horizontal surfaces such as equipment, ducts, pipes, hoods, ledges, beams and above suspended ceilings and other concealed surfaces, to minimize dust accumulations within operating areas of the facility. Vigorous sweeping or blowing down with steam or compressed air shall be permitted only under limited and controlled circumstances.
  • In areas containing a combustible dust hazard only industrial trucks listed or approved for the electrical classification of the area, as determined by Section 6.6, shall be used in accordance with NFPA 505, Fire Safety Standard for Powered Industrial Trucks Including Type Designations, Areas of Use, Conversions, Maintenance and Operations.
  • Personnel shall be trained to use portable fire extinguishers in a manner that minimizes the generation of dust clouds during discharge.