Online Safety Community

Wood Flour Dust Explosion/Fire. Excellent explanation by Fire Chief Andy Mason of process materials, situations, and conditions.

Factory fire causes $350,000 damage
http://www.wnewsj.com/main.asp?SectionID=49&SubSectionID=156&am...

Gary Huffenberger, Staff Writer, Wilmington News Journal did an excellent job in reporting the incident so as to provide the public with the specifics of the process. Additionally, Wilmington Fire Chief
Andy Mason shared with Gary important information that assists in understanding probability of occurrence throughout the manufacturing sector.

Views: 415

Replies to This Discussion

The weak link in addressing combustible dust related fires and explosions in the workplace is at the local jurisdictional level. The above example provides stakeholders an excellent example idea of how EHS professional must attempt to educate the media and fire protection professionals concerning combustible dust hazard awareness. The majority of news accounts of ComDust workplace incidents never provide the detailed information that Gary and Andy shared.
Another major dust related event in a process with many similar operating steps to general powder handling processes. It was interesting to read about the "ductwork explosions"; this is often forgotten when combustible dust process hazards are being assessed. Thanks for sharing, John.
I have protected many of these wood flour producers. This fire was likely caused by the dryer. Although many fires are also started in the grinding process.

For a wood flour composite extrusion process like this, they will typically dry wood flour to almost the combustion point, creating a highly flammable combustible dust in the process. They will typically use pneumatic conveying of the dried wood flour from the dryer. Depending on how the conveying, collection and storage systems are designed, this wood flour can also agglomerate and create build-up and stalactites within the ductwork at any joints, elbows and transitions, and also any joints or squared corners of the dust separator or collector. These stalactites and build-up can superheat in the hot air stream from the dryer, creating red hot ignition points within the ductwork and collector. Many times for humidity reasons, these dust collectors are located inside the building.

So you can see that super heated combustible dust within the dust collection or storage equipment can easily combust at many points in the process, be transported to other points in the process, and can also start to degrade and superheat within the storage bin. Without proper process and safety system design, this process is a time bomb. They have many of the same issues in the wood pellet and MDF industries - any process where they are grinding and drying wood flour.

In the process described in the article, wood flour is then mixed with other polymers, and extruded into plastic-wood decking, and other components.

Employees will often say afterward that they heard small booms or smelled smoke, but could not find the source. These are precursors to an event described in the article.

This process needs a process design and safety system design review; Fire Prevention equipment like Spark Detection and Suppression systems on all of the ductwork, and CO detection within storage bins; Fire Protection Equipment like sprinkler and deluge systems in the collectors and silos; Explosion Prevention and Protection equipment like venting and suppression in all critical collectors and storage equipment.
Agree with your assessment, Jeffrey.
Your welcome Antoni. Thanks Jeff for providing the excellent overview concerning layers of protection.
Thank you gentlemen, always appreciate feedback from my peers. We are all in this fight together.
John; this brings back to mind the OSHA hearings on the proposed ComDust regs. Any guess as to when we can expect the actually regs to be acted upon by Congress. Thanks.
Antoni, OSHA is still holding stakeholder meetings in an attempt to acquire additional input concerning a proposed regulation. In contrast, Congress is not aggressively pursuing legislation while OSHA is in the rulemaking stages.

RSS

Take our poll!

Take our poll!

Latest Activity

arifa khan posted a photo

WhatsApp Image 2017-03-29 at 11.23.33 AM

NEBOSH IGC to know more call immediately.
1 hour ago
Adam Fleaming posted a blog post

Effective cleaning validation procedures for analytical equipment

Regulatory agencies the world over have put in place stringent requirements for ensuring that cleaning validation procedures for analytical equipment are effective. Even if putting these practices in place involves expense and effort, it is worth the trouble, because the cost of noncompliance is much, much higher than that of compliance.Noncompliance with regulations for cleaning validation procedures for analytical equipment has a serious consequence: Regulatory bodies such as the FDA could…See More
6 hours ago
David Collins posted a blog post

What is the real role of a safety advisor?

The Role of Safety Advisor in Organisations – Essential ReadingWhilst everyone wants to do ‘safety differently’, it is not likely that reform will come within. The paradigm of safety with its primary focus on measurement actually mitigates any hope of innovation, creativity or critical thinking. If safety is now the…See More
13 hours ago
Prawit is now a member of Online Safety Community
yesterday

Discussion Forum

Homework Assignment for the ComDust group

"fire was contained to the dust collector.." Homework for the group-Is NAICS: 332111/Iron and Steel Forging in the OSHA ComDust NEP?Helpful resource for group homework assignment: Combustible Dust…Continue

Tags: combustible dust, OSHA, NEP., NAICS

Started by John Astad Jan 10, 2011.

Wood Dust Shaker dust collectors 7 Replies

I am currently doing a study on wood shop dust collectors. The majority of the installations are shaker style with the tube sheet located on the bottom. ie the dirty air flows inside the filter bag.…Continue

Started by John E. BAchynski. Last reply by Jeffrey Nichols Nov 7, 2010.

Combustible Dust Testing (Appendix E) Consultancy - Nanoview Associates LLC 2 Replies

This is Robert T Dombrowski - President / Principal Scientist of Nanoview Associates (NVA) LLCNanoview Associates (NVA) LLC offers a wide range of scientific / technical consulting services that help…Continue

Started by Robert T Dombrowski. Last reply by Robert T Dombrowski Feb 11, 2010.

OSHA Ventilation Standard Revise for Combustible Dust 1 Reply

Continue

Tags: Bureau, U.S., of, Mines, Standard

Started by John Astad. Last reply by Fred Ravenscraft Jan 20, 2010.

Badge

Loading…

© 2017   Created by Safety Community.   Powered by

Badges  |  Report an Issue  |  Terms of Service