The U.S. Chemical Safety and Hazard Investigation Board (CSB) has released a new safety video titled Deadly Dust – Explosions at Didion Milling. The video examines the 2017 corn dust explosions at the Didion Milling facility in Cambria, Wisconsin, which killed five workers and injured 14 others. Using animations and incident details, the video clearly shows how accumulated combustible dust led to both primary and secondary explosions — a common and deadly pattern in dust-related incidents.
The CSB determined the cause of the dust explosions and collapsed buildings was the ignition of combustible corn dust inside process equipment which transitioned to multiple explosions. Contributing to the severity of the explosions was Didion’s lack of engineering controls, which allowed the fire and explosions to propagate through the facility uncontrolled. The uncontrolled propagation of fire and explosions subsequently caused secondary explosions due to the inadequate fugitive dust management.
Other Related CSB Dust Videos
- Inferno: Dust Explosion at Imperial Sugar (2008 incident, updated video) — Documents the catastrophic sugar dust explosions in Port Wentworth, Georgia, that killed 14 workers and injured 38. This remains one of the most powerful illustrations of how secondary dust explosions can devastate a facility.
- Combustible Dust: An Insidious Hazard (2009) — A broader overview showing multiple dust incidents and why even small amounts of accumulated dust can create explosive conditions.
NFPA 660 – The New Consolidated Combustible Dust Standard
In response to these recurring tragedies, the National Fire Protection Association has released NFPA 660: Standard for Combustible Dusts and Particulate Solids. This new standard consolidates six previous dust-related standards (NFPA 61, NFPA 484, NFPA 652, NFPA 654, NFPA 655, and NFPA 664) into one comprehensive document. It provides updated requirements for hazard assessment, dust control, housekeeping, explosion protection, and fire prevention.
Why This Matters
Combustible dust incidents unfortunately continue to occur. Strong housekeeping, proper hazard evaluation, and consistent operational discipline are essential layers of protection. Many of the lessons from these events align directly with common audit findings and the need for rigorous adherence to procedures.
Have you reviewed your facility’s combustible dust housekeeping and hazard assessment programs recently? What challenges have you encountered with combustible dust control?
Recommended Resources
CSB-Reports
- Combustible Dust Hazard Investigation Page — Overview of CSB’s long-standing recommendations for a comprehensive OSHA standard.
- Deadly Dust – Explosions at Didion Milling — CSB Incident Report
- Inferno: Dust Explosion at Imperial Sugar — CSB Incident Report
NFPA & Standards
- NFPA 660: The New Standard on Combustible Dusts (GEAPS video/presentation) — Good practical explanation of what changed with the consolidation.
- “What Is a Combustible Dust Explosion?” (NFPA video) — Short, clear educational video.
Other Practical Resources
- Dust Safety Science — Excellent independent site with an incident database, podcast, research summaries, and practical guides. Very useful for real-world learning.
- OSHA Combustible Dust National Emphasis Program (NEP) — OSHA’s current inspection focus and guidance.