The document by Imperial Systems, Inc. emphasizes the importance of combustible dust safety programs to prevent catastrophic accidents, highlighting lessons learned from three incidents that resulted in multiple fatalities. Key takeaways include the need for effective hazard assessment during process changes, proper dust management, and employee awareness of combustible dust risks. The document advocates for comprehensive dust hazard analyses to prevent historical mistakes from repeating.

1. DON’T REPEAT HISTORY
Combustible Dust Safety Programs
a guide by IMPERIAL SYSTEMS, INC.

2. Every time a combustible dust accident
happens, you can make two assumptions.

3. Firstly, preventing the accident could have
been done with a combustible dust safety
program.

4. Secondly, the accident, or one just like it,
probably happened before. Maybe at a
different company or in another place, but
some things stay the same.

5. With combustible dust accidents, history does
repeat itself.

6. The U.S. Chemical Safety Board has
investigated several combustible dust
incidents and identified the failures that lead
to them. Learning from the mistakes made
at other facilities can prevent catastrophe in
yours.
Let’s take a look at a few recent combustible dust incidents and what
we can take away from their stories.

7. West Pharmaceutical Dust Explosion
Incident One

8. Despite good housekeeping, polyethylene
dust was able to enter the ventilation system
and settle above the drop ceiling. The
accumulated dust exploded, blowing the
building apart and killing six people.

9. Combustible dust can accumulate in unseen
or unexpected places, even when the machine
area looks clean.
Lesson One

10. Process change management could have
determined that switching from zinc stearate
powder to a polyethylene powder created
a new risk. Changes in a process must be
assessed for any new hazards.
Lesson Two

11. Dust testing saves lives. The polyethylene dust
was more combustible than anyone realized.
Even safety inspectors had not addressed
combustible dust risks.
Lesson Three

12. CTA Acoustics Dust Explosion
Incident Two

13. Collected resin dust from this fiberglass
insulation manufacturer was discharged into
a cardboard box on the production floor.
Additional debris was dumped on the facility’s
roof. An initial explosion in one of the facility’s
ovens lead to several secondary explosions
and seven people died.

14. A poorly operating dust collector puts the
entire facility at risk. Overloaded, dirty bags
and unsafe dust disposal lead to this incident.
Lesson One

15. When dealing with combustible dust,
compressed air should never be used for
general cleaning. It raises clouds of dust
that can settle out of reach overhead. NFPA
standards warn against compressed air
cleaning in work areas.
Lesson Two

16. A combustible dust safety plan did not
exist. Many employees didn’t know the dust
was combustible. The danger of storing
combustible dust in cardboard boxes and on
the roof was not addressed.
Lesson Three

17. Warning signs went unrecognized. The
employees commonly put out small fires in the
furnaces, considering them a minor problem.
However, each fire could have ignited a dust
explosion.
Lesson Four

18. Hayes Lemmerz International
Incident Three

19. In the area of the facility where aluminum
chips and scrap were reclaimed, chips began
backing up in the dust collection system and
ductwork. Aluminum is extremely combustible,
and an explosion occured in the collector
and ductwork. Inadequate venting caused
secondary explosions. Many employees were
burned and one died.

20. A combustible dust safety plan must include
housekeeping. When interviewed, employees
and management told investigators they
didn’t realize the buildup of dust could be
dangerous.
Lesson One

21. The dust collector did not meet NFPA
standards. It could not withstand the force of
the explosion or vent it safely. It also had no
prevention to keep flame from traveling back
into the building.
Lesson Two

22. The facility drastically underestimated the
flammability of their dust. It’s impossible to
make a safety plan without understanding the
materials being handled.
Lesson Three

23. • A dust collector designed for your application
• Fire and explosion safety features in the dust collection system
• Housekeeping to remove dust, even in hidden places
• Maintenance of machines that handle dust
• Control of ignition sources
• Dust testing and employee awareness of dust hazards
• Combustible dust training, including how to manage a combustible
dust incident
Preventing Gaps in Your Combustible Dust Safety Program

24. Previous incidents point to mistakes in safety
processes. We can prevent these mistakes
from happening again.

25. A full dust hazard analysis will identify
potential problems before they become
accidents. If you need help addressing dust
problems in your facility, contact us for help.