2025 Spring Meeting and 21st Global Congress on Process Safety
(32bh) Dust Hazard Analysis
This timeline also documents major changes made by regulators to address the hazards of combustible dusts based on the publication of the Combustible Dust Hazard Study by the CSB. In 2007, The United States Department of Labor’s Occupational Safety and Health Administration (OSHA) initiated a National Emphasis Program (NEP) to address the deflagration, other fire, and explosion hazards that may exist at facilities handling combustible dust. The purpose of the NEP was to inspect facilities that generate or handle combustible dusts by defining materials of concern, typical industries associated with such materials, operations that could result in increased risk of a fire, deflagration, or explosion hazards[2].
In 2009, OSHA published an Advanced Notice of Proposed Rulemaking (ANPR). This ANPR requested comments, data, and other information related to the hazards of combustible dust in the workplace with an intent to use the information to develop a standard for combustible dust[3]. OSHA’s preliminary data collection efforts indicated that there were 422 incidents from 1980-2008 in industries having at least one recorded combustible dust incident. In industries where combustible dust fires or explosions have occurred, they were associated with 426,000 industry establishments employing approximately 16 million workers[4]. This analysis resulted in a risk potential of approximately 1 in every 1,009 of the identified industry facilities being at risk of an incident. OSHA published Firefighting Precautions at Facilities with Combustible Dusts in 2013 as a guide to assist with emergency responders who may face incidents related to combustible dusts[5]. In 2017, OSHA withdrew its rulemaking proposal due to resource constraints and other priorities[6].
OSHA was not the only industry regulator that was attempting to address these hazards. In 2012, the International Code Council (ICC) released the 2012 Edition of the International Fire Code (IFC). This was the first edition of the IFC to include a chapter specific to combustible dust-producing operations[7]. IFC, Chapter 22 included permitting requirements, precautions to limit the source of ignition by improving housekeeping efforts, and explosion protection standards that may be applicable at the discretion of the fire code official. This edition of the IFC also introduced the “Note q” provision in Table 5003.1.1(1) Maximum Allowable Quantity (MAQ) per Control Area of Hazardous Materials Posing a Physical Hazard. This required that a report be developed in accordance with IFC, Section 104.7.2 where such materials are manufactured, generated or stored in a manner that the concentration and conditions create a fire or explosion hazard[8].
The technical opinion and report required by IFC, Table 5003.1.1(1) is required to meet the following criteria[9]:
- The opinion and report shall be prepared by:
- Qualified engineer,
- Specialist,
- Laboratory or fire safety specialty organization acceptable to the fire code official.
- Report shall analyze:
- Fire safety properties of the design,
- Operation or use of the building or premises and the facilities and appurtenances situated thereon, and
- Recommended necessary changes.
This approach by the ICC has remained consistent among the 2015 and 2018 editions of the IFC, with the later requiring that equipment, processes, and operations be compliant with the IFC and NFPA 652, The Fundamentals of Combustible Dust, 2016 Edition. In addition to compliance with NFPA 652, the 2018 Edition of the IFC also required the facility owner or operator to conduct a Dust Hazard Analysis (DHA) in accordance with the requirements of NFPA 652. The 2018 Edition of the IFC also required that existing facilities have a DHA completed[10]. This was the first instance of retroactive DHA requirements.
The first edition of NFPA 652 (2016 Edition) was developed to provide the general requirements for management of combustible dust fires, deflagrations, and explosion hazards. This is accomplished by presenting general requirements and referencing other standards, that are applicable based on material or use, to manage dusts, ignition sources, and limit impacts of explosions by prescribing minimum construction, protection, isolation, and housekeeping requirements[11].
The history, and requirements associated with managing the risks associated with combustible dusts are fairly new and not well communicated. To add complexity to this topic, the ability to identify and mitigate the risks associated with combustible dust fires, deflagrations, and explosions often requires a team of specialists due to the nature and complexity of process operations.
The poster will focus on identification and risk ranking of ignition sources, including various forms of electrostatic discharge (ESD). While higher-energy ignition sources such as hot work and open flames are well understood, there are multiple forms of ESD that can serve as credible ignition sources for even moderately explosible combustible dusts. Our work for various chemical process industries including specialty chemistry, metals and pharmaceuticals will highlight multiple types of chemical processes that are subject to static electric potential, different options for mitigation, and implementation challenges.
[1] https://www.csb.gov/combustible-dust-timeline/
[2] https://www.csb.gov/combustible-dust-timeline/
[3] https://www.osha.gov/laws-regs/federalregister/2009-10-21
[4] https://www.osha.gov/sites/default/files/publications/OSHA_3644.pdf
[5] https://www.osha.gov/sites/default/files/publications/OSHA_3644.pdf
[6] https://www.csb.gov/combustible-dust-timeline/
[7] https://codes.iccsafe.org/content/IFC2012/chapter-22-combustible-dust-producing-operations
[8] IFC, Table 5003.1.1(1) (2012 Edition).
[9] IFC, §104.7.2 (2012 Edition).
[10] IFC, §2203.2 (2018 Edition)
[11] NFPA 652, Standard on the Fundamentals of Combustible Dust, 2016 Edition.