Control of Combustible Dusts: Preventing Fires and Explosions in Industrial Facilities
Combustible dust is one of the most overlooked hazards in industrial and manufacturing facilities. While often invisible or ignored, layers of dust and particles suspended in the air can create the conditions for a devastating fire or explosion. At HITE Engineering, we help organizations evaluate hazards related to dust accumulation, test for combustibility and other hazardous properties, and implement engineering controls to ensure regulatory compliance and safety.
Why Combustible Dusts Are Dangerous
When fine particles of materials such as aluminum, grain, sugar, flour, plastic, or wood become airborne in sufficient concentration, they can ignite with catastrophic results. A single spark, open flame, or even hot surface can trigger a chain reaction, leading to flash fires or explosions.
Historical accidents, such as the Imperial Sugar explosion in Georgia (2008), demonstrate how quickly dust hazards can escalate, killing workers, destroying facilities, and leading to multi-million-dollar fines and lawsuits. Canadian workplaces are no exception, with CCOHS highlighting combustible dust as a persistent national safety concern.
Warning Signs of Dust Hazards
- Layers of dust on beams, floors, or surfaces thicker than a dime
- A visible haze in the air, especially under certain lighting conditions
- Accumulations near ignition sources such as motors, welding areas, or hot surfaces
- Housekeeping practices that rely on compressed air (which may spread dust clouds)
Is Your Dust Combustible?
Not all dusts are combustible — but many are. Even common materials such as flour, plastic pellets, and aluminum can present significant hazards when reduced to fine particles, and the finer the particles the greater the risk. The only way to know for sure is through dust testing. At HITE Engineering, we facilitate professional ASTM defined laboratory based testing and technical compliance reviews to confirm whether your facility’s dust presents an ignition risk.
Testing typically measures parameters such as Minimum Ignition Energy (MIE), Maximum Explosion Pressure (Pmax), and Dust Deflagration Index (Kst) values, as outlined in NFPA 652 and NFPA 654.
Ventilation and Mitigation Requirements
Once identified, combustible dust hazards can often be controlled through:
- Local exhaust ventilation (LEV): Capturing dust at its source
- Proper housekeeping: Vacuuming with explosion-rated systems
- Ignition control: Eliminating open flames, sparks, and hot surfaces
- Explosion venting/suppression systems: Engineering controls to mitigate potential incidents
- Safe storage and handling: Minimizing transfer points and dust escape
Compliance Requirements
In Ontario, combustible dust hazards fall under the Occupational Health and Safety Act (OHSA), which requires employers to provide a safe workplace. Federally recognized standards such as NFPA 652 (Fundamentals of Combustible Dust) and NFPA 654 (Prevention of Fire and Dust Explosions) provide detailed requirements for hazard analysis and control measures. Failure to comply can result in orders, fines, and liability in the event of an accident.
How HITE Engineering Can Help
HITE Engineering offers a full range of services to identify, test, and mitigate combustible dust hazards, including:
- Dust hazard assessments and inspections including Hazardous Area Classifications
- Combustibility and hazardous parameter testing services
- Engineering design of ventilation and dust collection systems
- Compliance audits against OHSA, NFPA, and CSA standards
- Training for facility staff and maintenance teams
By working with HITE, you can protect your employees, comply with regulations, and avoid the financial and reputational damage associated with dust-related incidents.
FAQ: Combustible Dust Hazards & Testing
What is combustible dust?
Combustible dust is any fine particulate material that can catch fire or explode when suspended in air in the right concentration. Common examples include aluminum, flour, sugar, plastics, grain, and wood dusts.
How do I know if my facility has combustible dust hazards?
Look for layers of dust on surfaces, visible haze in the air, or accumulations near equipment. The only definitive method is laboratory testing to confirm combustibility properties.
Which standards govern combustible dust safety?
Key standards include NFPA 652 (Fundamentals of Combustible Dust), NFPA 654 (Prevention of Fire and Dust Explosions), and Canada’s OHSA requirements for safe workplaces.
How often should dust testing be performed?
Facilities should conduct testing whenever new processes are introduced or material handling changes occur. As a best practice, testing should be repeated every 3–5 years to ensure ongoing compliance.
What are the consequences of ignoring combustible dust risks?
Ignoring dust hazards can lead to catastrophic fires or explosions, worker injuries, liability lawsuits, fines, and loss of property. Proactive testing and mitigation are far less costly than an incident.
Contact Us
Don’t wait until an inspector — or an accident — forces action. Contact HITE Engineering today to schedule a dust hazard assessment or testing program for your facility.
