Combustible Dust Explosions and Fires-ATEX

Mystery of Airborne Combustible Dust Concentrations

messinabout@earthlink.net (John Astad) — Fri, 27 Jan 2012 21:55:00 +0000

So at what threshold should airborne concentrations of combustible dust trigger a concern for combustible dust related fires and explosions? Mention of industrial hygiene issues is reminiscent of the 2011 Foxconn catastrophic dust explosion in China, where initially workers complained of high levels of aluminum dust respiratory exposure during polishing operations.

Confusion still exists according to media accounts of the high airborne dust levels discovered in the WorkSafeBC inspections at the British Columbia, Canada facility a few weeks prior to Fridays catastrophic explosion. These high levels were for airborne concentrations in regards to respiratory exposure not combustible dust explosive concentration levels. Explosive airborne dust concentrations would require approximately 30,000 times more than the concentration found in the inspections depending on moisture content and particle size. For example, the highest airborne concentration was 5.9 milligrams/cubic meter, which was 2 times over the acceptable threshold of 2.5 milligrams/cubic meter, according to WorkSafeBC inspection reports released to the media.

To put this into perspective we must ask what exactly is 2.5 milligrams? Well if you put a pesky mosquito on a laboratory scale that would be your answer. Of course mosquitoes are not processed in sawmills, lumber is. But this does provide a general idea of 2.5 milligrams of mass. Alternately, using the mass of wooden toothpick provides better idea of how high suspended dust concentrations would be in one cubic meter of volume, such as the volume of a huge glass fish tank.

So here is the math. On an average, a wooden toothpick weighs approx. 100 milligrams on a laboratory scale. Now dissect the toothpick into 40 parts, which would equate to each of the forty toothpick parts weighing the same as a 2.5 milligram mosquito.

Now take three of those individual 2.5 milligram toothpick parts and grind them up to the consistency of sawdust. This would provide about total 7.5 milligrams of mass, a little over the 5.9 milligrams of the high airborne dust level that inspectors found in a cubic meter during the prior facility inspection.

So one must ask, is approx. 1/10 of wooden toothpick sawdust explosive in a cubic meter volume of air? The basis of a combustible dust explosive atmosphere is that the minimum explosive concentration (MEC) must be sufficient to have ignition while in suspension when combined with the fire triangle.Think of MEC analogous to the lower flammable/explosive level LFL/LEL of a flammable vapor or gas.

In contrast a minimum explosive concentration (MEC) of sawdust depending on moisture content and particle size is approximately 300 wooden toothpicks, weighing approximately 30 grams or 30 grams/cubic meter.Hope this helps obtaining insight in the difference between airborne respiratory hazards (milligrams) in contrast to airborne explosive concentrations (grams) of combustible dust. Of extreme importance is to ensure horizontal layers of dusts do not become airborne where a safe respiratory concentration can escalate rapidly into a minimum explosive concentration (MEC). Good housekeeping is key in this respect.

Combustible Dust Workshop: Managing a Complex Occupational Hazard

messinabout@earthlink.net (John Astad) — Fri, 27 Jan 2012 19:47:00 +0000

Wisconsin Combustible Dust Workshop in Milwaukee, Thursday February 23, 2012. Federation of Environmental Technologists, Inc. (FET), WI CHMM Chapter.

Agenda

Chairman and WI CHMM Chapter President Mike McCoy

Combustible Dust Overview: Dr. George Gruetzmacher, WI State Laboratory of Hygiene

Regulatory Aspects of Combustible Dust and Potential Rulemaking: George Yoksas, OSHA

Combustible Dust – OSHA’s National Emphasis Program (NEP) Casts a Broad Net David McClurg, Esq., Petrie & Stocking, S.C.

Understanding and Interpreting Combustible Dust Analytical Data: Brian Kingsley, Chillworth Global

Combustible Dust Protection Systems: Dave Grandaw, Fenwal

Notable Combustible Dust Explosions and Lessons Learned: John Astad, Combustible Dust Policy Institute

Resources
WI CHMM Chapter
Federation of Environmental Technologists

Full Report: Explosion of DeBruce Grain Elevator, Wichita, Kansas; June 8, 1998

messinabout@earthlink.net (John Astad) — Thu, 26 Jan 2012 19:42:00 +0000

Global Incident Awareness Can Save Lives

messinabout@earthlink.net (John Astad) — Fri, 28 Jan 2011 21:08:00 +0000

Two strikingly similiar pictures, two different countries, yet the explosive effects in these storage tanks were basically the same in the liquor pulping recovery process. In both catastrophic incidents fatalities occurred at corrugated packaging manufacturing facilities. The incident in France happened this month and the other in Wisconsin back in 2008, which the Chemical Safety Board is currently investigating. As a result of the Wisconsin incident CSB issued a March 2010 Safety Bulletin on Hazards of Welding and other Hot Work.

Christian Bourdon, the contract worker from Saint-Aubin, France died unnecessarily in the hospital as a result of injuries sustained from the explosion while doing hot work on the storage tank. Don't know if Christian or others in the global workforce had a chance to read the educational CSB bulletin. Incident investigations determining root cause and safety bulletins are great if the information is being received by OHS professionals then passed on to the workforce. Yet it is difficult to understand why repeatable catastrophic incidents are occurring when information is abundant concerning the hazards. Providing examples of these two incidents is even harder to grasp since the manufacturing and storage process were the same.

It is unacceptable that life-saving information resides securely within national borders when occupational health and safety is a global concern. In contrast global financial markets send and receive data real-time. So is the value of the buck of more importance than human life?

Resources
Paper & Pulp Mill Process Magnetrol International

Legislators, More Regulation is the ComDust Cure

messinabout@earthlink.net (John Astad) — Mon, 17 Jan 2011 07:49:00 +0000

Why is it that legislators seem to think that passing more bills and regulations is the cure all? Problem with the combustible dust issue is that no one in Washington D.C. has all the facts and solely utilizing the Chemical Safety Board's Dust Hazard Study provides a false perception of the enormity and complexity of the issues both social and economical.

"Their bill would tell OSHA to issue - within 90 days - an interim standard. It would require better housekeeping, engineering controls, worker training and a written combustible-dust safety program."
Savannahnow.com-news article

For example, the CSB report states there were 281 ComDust incidents from 1980-2005, or an average of eleven incidents annually. In stark contrast, according to media accounts of ComDust related incidents since 2008 there have on an average 12 incidents a month. This would equate to approximately 4,000 ComDust incidents during the 1980-2005 timeframe.

Not understanding the depth of the issue is only part of the problem. For example FEMA/U.S. Fire Administration's, "National Fire Incident Reporting System 5.0 (NFIRS)" via local fire departments has failed to report and identify process situations, process conditions, and process materials regarding combustible dust related fires, precursors to catastrophic dust explosions.

If the local fire and explosions hazards can't be identified, then how can they be evaluated and controlled? Of course legislators at the national level seem to think legislation and regulation is the answer for a local/regional problem. That is the easy way out in attempting to solve a primarily fire life safety issue and secondarily an occupational safety issue.

The OSH ACT specifically states that to address workplace safety, issues of regulation, education, outreach, and research must be pursued. OSHA with its limited resources cannot do it all.

"by providing for research, information, education, and training in the field of occupational safety and health; and for other purposes."

What happened to NIOSH as the OSH ACT intended in getting involved with outreach/education regarding the combustible dust issue as it had done decades ago concerning coal mine dust explosions, prior to when the U.S Bureau of Mines (USBM) was transferred to NIOSH, Department of Energy (DOE), U.S. Geological Survey, and the Bureau of Land Management in 1995-97.

Let’s all grow up and stop singling out Imperial Sugar explosion as the problem. Currently Imperial Sugar is an industry leader in addressing ComDust fire and explosion hazards. What about the tens of thousands manufacturing facilities that have potential ComDust fire and explosion hazards? So now OSHA as Secretary of Labor states, "there's a new sheriff in town." So what we going to do, fine them all?

Outreach, training, research, and education through NIOSH and US Fire Administration are just a few examples in alternatives to more legislation and regulation. Question is, who has the vision in providing the leadership so all local, state, and federal agencies are working together in these tough economic times.

Resources -OSH Act

Ten ComDust incidents per year...Say What?

messinabout@earthlink.net (John Astad) — Sat, 15 Jan 2011 06:28:00 +0000

At a recent combustible dust webinar last October, attendees to the educational event learned that about ten combustible dust incidents occurred annually from the early 1980s until 2005 in the U.S.A. This data was obtained from the Chemical Safety Board Dust Hazard Investigation that was completed in 2006, noting 281 ComDust incidents from 1980-2005.

Unfortunately, this is not reality in contrast to media reports that note over ten combustible dust incidents every month. Currently, OSHA is in the combustible dust rulemaking process utilizing this incomplete data from the CSB Dust Hazard Study. This presents a problem by not exposing the enormity and complexity of combustible dust related fires and explosions in the manufacturing, non-manufacturing, and utility sectors.

The problem is exasperated by the current OSHA Combustible Dust National Emphasis Program (NEP) that further lessens the magnitude of combustible dust incidents by solely listing certain national industries (NAICS) that have a potential for combustible dust incidents and excluding thousands of other manufacturing plants that do have a history of ComDust incidents not listed in the ComDust NEP. For example, in 2008 over 50% of facilities that had ComDust incidents were not listed in the Appendices D-1 and D-2 of the NEP.

If your facility generates combustible dust it doesn't matter whether OSHA acknowledges the hazard our not in the ComDust NEP. Bottom-line, you have a potential fire and explosion hazard that can cause grave burn injuries, fatalities, and severe property damage. Get your dust tested now or at least conduct a thorough process hazard analysis; identifying, evaluating, and hopefully controlling the hazard.

To learn more about combustible dust hazards be sure to check out the excellent Chemical Processing. com webinar moderated by Traci Purdum, Senior Editor/Digital Media. Presenters included Dr Vahid Ebadat Ph.D/Chilworth Technology, Inc., John Dauber, sales manager/Camfil Farr APC, Bob Korn, Director of Sales for Explosion Protection Products/Fike Corporation, and Guy Colonna, Division Manager, managing the Industrial and Chemical Engineering department for the National Fire Protection Association.

Resources
Google Map Dec 2010-Jan 2011 Combustible dust related fires and explosions
Dust Gets it's Due- By Seán Ottewell, Editor at Large-Chemical Processing.com

Confined Structure Fires also Combustible Dust Related?

messinabout@earthlink.net (John Astad) — Sat, 15 Jan 2011 03:08:00 +0000

Just prior to the Christmas holiday a minor combustible dust related fire occurred in a dust collector at a Misc. Fabricated Metal Producing Manufacturing/NAICS 332999 facility in Wisconsin. These type of facilities are listed in Appendix D-2 of the OSHA ComDust NEP as Fabricated Metal Products, Not Elsewhere Classified with industries that may have Potential for Combustible Dust Explosions/Fires.

According to the news account:

The fire was extinguished and contained to the dust collector bag house. There was no fire extension into manufacturing plant.

WQOW.Com

The incident begs the question was this a confined structure fire? Where as in similiar small fire incidents that are limited in scope, are confined to noncombustible containers, rarely result in serious injury or large content losses, and are expected to have no accompanying property losses due to flame damage. The news account mentions no fire extension into manufacturing plant nor injuries which resulted in an estimated $10,000 damage to dust collection bag house. Since dust collectors are constructed of metal they would be non-combustible.

In the U.S. Fire Administration/National Fire Data Center, Investigation of Confined Structure Fires, Topical Fire Research Series, the report noted 2002 NFIRS 5.0 data contain abbreviated reporting for slightly over 52,000 confined structure fire incidents—37% of structure fires.These incidents accounted for $26 million in combined losses, 3 deaths, and nearly 500 injuries. Most confined structure fires (77.5%) occurred on residential properties. It is the other 23% that we are concerned about in manufacturing non-residential properties.

There is a problem in this US Fire Administration reporting in that it does not formally consider dust collectors or other process equipment in the manufacturing sector that are non-combustible as confined structure fires. Instead, cooking fires, trash or rubbish fires, chimney fires, commercial compactor, fuel burners, and incinerators are used as data element descriptors in these type of fires.

This does present a problem since fire service professionals can't identify combustible dust fire hazards in the NFIRS 5.0 reporting system, then how can they assist stakeholders in evaluating and controlling combustible dust fire hazards. All combustible dust related fires are failed catastrophic combustible dust explosions. Time is way overdue for the FEMA/US Fire Administration's National Fire Data Center to review their fire reporting methodology that omits the dozens of minor combustible dust related fires that have a history of evolving into catastrophic dust explosions.

Combustible Dust Explosion Pharmaceutical Preparation Plant

messinabout@earthlink.net (John Astad) — Sat, 15 Jan 2011 01:22:00 +0000

A combustible dust explosion occurred at a pharmaceutical preparation plant in Iowa prior to the end of the 2010 a few weeks ago. Luckily there were no injuries or fatalities and damage was minor according to the news account.

"There were no injuries. The explosion blew out doors on the building and dust collectors, with additional minor damage."

Eastern Iowa News Now

It appears the mention of doors blowing out in the dust collector might be referring to explosion ventilation panels. Being that the plant is involved in pharmaceutical preparation with a NAICS 325412, it is noted in the OSHA Combustible Dust NEP in Appendix D-1 as an Industries with More Frequent and/or High Consequence Combustible Dust Explosions/Fires.

Over the past 12 months OSHA has been enforcing a myriad of regulations in addition to ComDust NEP emphasis in their site visits at pharmaceutical preparation facilities. The OSHA Integrated Management Information System also referred to as IMIS provides a helpful insight to these inspections.

An educational General Duty Clause citation for one Pharmaceutical Preparation Plant noted that "neither dust collector was equipped with deflagration venting panels directed to an unoccupied area or with a suppression system. The collectors were located inside an occupied area which employees entered to conduct maintenance on a daily basis."This is in contrast to the current incident where the dust collector was installed outside on the roof and appeared to have explosion vent panels.

Results of an internet search produced a MSDS for microcrystalline cellulose (MCC) Cellulose; flour cellulose which has combustible dust fire explosion hazards. For example in the Fire Fighting section it notes, "Fine dust dispersed in air in sufficient concentrations, and in the presence of an ignition source is a potential dust explosion hazard. For Cellulose: Minimum ignition temperature, dust cloud: 410C. Minimum explosible concentration: 0.045 g/l." This is helpful information so stakeholders can take proper administrative, PPE, and engineering control measures.

On a side note, another combustible dust related fire and explosion originated from the same company that occurred nearly two weeks prior to above incident, yet paper dust was the process material at a different facility instead of microcrystalline cellulose (MCC) according to the news account.

“Something caused the paper dust to explode. We don’t know what it was,” Battalion Chief Rick Palmer of the Portage Fire Department said. Palmer said the fire department has been called to explosions at the plant in the past, most recently about eight months ago. Small fires can develop wherever the dust settles in the plant following such an explosion, he said. “We just chase little fires all over the place,”

Michigan Live.com

Stakeholders searching the OSHA Combustible Dust NEP will not find any paper industries that OSHA believes have More Frequent and/or High Consequence Combustible Dust Explosions/Fires or Potential for Combustible Dust Explosions/Fires. Don't know what the NAICS is for the facility that generated paper dust in the news account yet there is mention that the facility produces paper insulation. In either case whether or not a facility is listed in the OSHA ComDust NEP, if you generate ComDust then you need to identify, evaluate, and control the fire and explosion hazards.

U.K Combustible Dust Fire with Metal Dust

messinabout@earthlink.net (John Astad) — Fri, 14 Jan 2011 03:36:00 +0000

“The fire was on the mezzanine floor in a hopper containing metal dust"
www.miltonkeynes.co.uk

OSHA needs to look at DSEAR and ATEX and include ComDust in the universe of potentially explosive atmospheres in the rulemaking process, which also includes flammable liquids, gases, vapors, and mists. Can't continue like the present situation in the USA with ComDust as a separate entity. Until then, the US Fire Administration will continue to ignore the fire and explosion hazards of ComDust with deficient incident reporting in the National Fire Incident Reporting System NFIRS 5.0

Process Upset Causes Combustible Dust Related Fire

messinabout@earthlink.net (John Astad) — Fri, 14 Jan 2011 02:19:00 +0000

Another minor combustible dust fire in the news with no injuries or fatalities. That is the good news..Yet stakeholders need to be aware that besides hot surfaces, arcs, sparks, static electricity, etc (process situations) that can ignite combustible dust, so can process upsets such as the case in this incident.

"combination of water and molten steel can cause a flash-up. That flash of fire likely set dust on fire, which then spread to a nearby storage room." (Watch the video)

WTOL-news article

OSHA is in the rulemaking process for a combustible dust regulation that is a continuum of the OSHA Combustible Dust National Emphasis Program (NEP). The primary problem with this approach, is that it solely notes specific national industries (NAICS) that supposedly have a high probability or high consequence or potential for combustible dust incidents and ignoring others with potential fire/explosion hazards. Now for the bad news.. According to media account, over 50% of combustible dust related fires and explosions occur in national industries (NAICS) not listed in the the OSHA ComDust NEP, such as the case with this incident

For example, the real eye opener concerning this minor incident, is that this facility is an iron and steel mill national industry (NAICS 331111), which is not acknowledged in the OSHA Dust NEP as having high probability/consequence or potential for combustible dust incidents. So if the tree fell in the forest and no one heard it, did it fall?

There are dozens of other national industries composed of thousands of facilities in the wood, paper, plastic, metal, chemical, and food manufacturing sectors not listed in the OSHA ComDust NEP that have regular occurring minor combustible related dust fires which don't get notice from many other stakeholders either. This attitude is attributed to normalization of deviation as what occurred in the events leading up to the 1986 Space Shuttle Challenger disaster. Same thing with a catastrophic dust explosion as it is a rare event also.

It is time to face reality and get with the program, understanding the ComDust fire/explosion problem is a process condition (equipment) issue and not solely a national industry (NAICS) subject. Whether an industry is listed in the OSHA ComDust NEP or not as a non-NEP NAICS, they all have similar process materials (combustible dust) and process situations (ignition sources). So how can we say that one national industry has high probability/consequence or potential for a combustible dust incident because it is listed yet another one doesn't because it is not listed in the NEP? Yet both industries generate combustible dust during the manufacturing process. This train of thought does not hold water as America is burning. Just remember that any minor combustible dust related fire is a failed catastrophic combustible dust explosion.

Posted via email from ComDust

Combustible Dust Fire Incident Reporting Deficiencies

messinabout@earthlink.net (John Astad) — Thu, 13 Jan 2011 02:56:00 +0000

A problem arises in the national fire reporting system where there are no data elements specifically identifying manufacturing process equipment involved in ignition of combustible dust. If process condition fire hazards can't be identified, then how can they be properly evaluated and controlled through administrative, PPE and best engineering practices?

"Stakeholders seeking control measures to minimize the probability and severity of combustible dust incidents should work more closely with the fire service."

ohsonline.com-article

Posted via email from ComDust

Resources:

1. National Fire Incident Reporting System (NFIRS 5.0) Complete Reference Guide

2. Report on Confined Structure Fires-February 2006, US Fire Administration

3. U.S. Industrial and Manufacturing Property Structure Fires, Oct. 2009, NFPA Fire Analysis and Research Division

4. US Chemical Safety Board, Combustible Dust Hazard Investigation, Nov. 2006

5. NFPA 901 Standard Classifications for Incident Reporting and Fire Protection

Biofuel Fires and Explosions-Google Maps

messinabout@earthlink.net (John Astad) — Wed, 12 Jan 2011 16:48:00 +0000

Google Maps

Ethanol Plant Fires and Explosions

Biodiesel Plant Fires and Explosions

Maps Compiled by John Astad, Director/Research Analyst, Combustible Dust Policy Institute

Combine Harvester Combustible Dust Fires

messinabout@earthlink.net (John Astad) — Wed, 12 Jan 2011 10:37:00 +0000

Informative article on the results of a research study on combustible dust related fires occurring in combine harvesters in the agricultural sector. The harvester diesel engine creates high temperatures resulting in very hot surfaces that can easily ignite the build-up of combustible dust that has low minimum ignition temperatures (MIT).
Stock & Land/Fairfax Media

The entire manufacturing sector can learn from this study as the process situations (ignition sources) of hot surfaces and static electricity can ignite combustible dust at facilities just like that do on a combine harvester. Good housekeeping is essential in minimizing the probability of occurrence in either case.

Posted via email from ComDust

Combustible Dust Fires. "It's the nature of the business"

messinabout@earthlink.net (John Astad) — Wed, 12 Jan 2011 09:06:00 +0000

Fire Chief states, "It's the nature of the business." "Part of the problem is the nature of the process that's there. It lends itself to having a fire to begin with. And it's not their fault" Caledon Enterprise

That is the problem here in the USA as many fire departments also believe it's the nature of the business and not the facilities fault. Fires in hoppers, dust collectors, etc. are really confined structure fires occuring in non-combustible containers in addition to in most cases; no fatalities, minor injuries, and no property damage.

Basically we are talking about a smoke scare and that is why these incidents are not reported in the US Fire Administration NFIRS 5.0. Why do we have to wait for a catastrophic ComDust explosion to take proactive action?

Posted via email from ComDust

Explosion Vents Reduce Severity of Explosion

messinabout@earthlink.net (John Astad) — Wed, 12 Jan 2011 07:52:00 +0000

Grain elevator had prior explosion in 2008 which caused much more damage and a worker injury. CEO notes that explosion protection best engineering practices lessened the severity of this recent explosion. This incident is a prime example of how ComDust incidents will continue to occur and only the probability and severity can be reduced through PPE, best engineering, and administrative controls.

Posted via email from ComDust

Fine dust buildup at Winnipeg feed-processing operation

messinabout@earthlink.net (John Astad) — Wed, 12 Jan 2011 07:38:00 +0000

"It's believed a spark from the machinery inside the hopper ignited the blaze, which is burning in the feed residue that had been encrusted along the walls of the bin." Prior fire several days earlier causing an estimated $20,000 damage.Winnipeg Free Press

Many other manufacturing facilities have similiar process situations (ignition sources) where either a spark or spontaneous ignition can ignite the process materials causing a combustible dust related fire. Good housekeeping and maintenance is essential in removing the buildup of combustible dust or residue. Without the fuel, a combustible dust related fire will not occur.

Posted via email from ComDust

Combustible Dust Laboratory Testing Primer

messinabout@earthlink.net (John Astad) — Fri, 07 Jan 2011 15:49:00 +0000

Potential combustible dust fires and explosions in the manufacturing, non-manufacturing, and utility sectors is a global problem. Across international borders the occupational safety regulatory standards for addressing combustible dust fire and explosion hazards varies. In contrast, the laboratory equipment in evaluating the hazard for ignition sensitivity and explosion severity is uniform with minor differences in methodology. For example, the 20 liter sphere is utilized worldwide in obtaining vital information on the maximum pressure and deflagration index (Kst) of combustible dust.

An excellent depiction of a dust explosion shown in the high speed video, shot at 600 frames per second, with 1 gram of custard powder dispersed in a glass tube past a hot coil ignition source. The glass tube has a volume of 1.2 litres, providing an explosive dust concentration of approximately 830 g/m3. Notice how the explosion pressure wave drives the dust ahead of it and out of the tube and debris from the explosion - mostly pieces of unburnt powder - continue to fall for some time afterwards. The second video sequence shows the same quantity of custard powder being ignited, but viewed from above. Note the thin plastic film held across the tube opening that acts as an explosion relief vent.

The catastrophic Imperial Sugar Refinery dust explosion in 2008 reminded global stakeholders how devastating industrial dust explosions can be. Measuring the explosive properties of the material being handled is, of course, the essential first step to understanding the hazard. Michael Ward of Explosion Hazard Testing in the U.K. has written an educational and very useful guide to explain combustible dust testing and what the lab results tell us in terms of explosion prevention and protection options.

The main points that the guide discusses:

UK statistics for fire and explosion

What a dust explosion is and the terminology involved

What laboratory tests are available and how they are conducted

What they tell us about the fire and explosive properties of the material

What tests are considered mandatory under U.K. and and EU legislation

The dust testing guide can be downloaded for free here

Book Review: Dust Explosions in the Process Industries, 3rd Edition

messinabout@earthlink.net (John Astad) — Wed, 01 Sep 2010 11:11:00 +0000

Fires and dust explosions are common and costly in many industries. In this book Eckhoff has organized a comprehensive overview of his practical knowledge of the origin, development, prevention and mitigation of dust explosions, an up to date evaluation of testing methods, design measures and safe operating techniques.

Included are the research and findings of many other scientists, creating a definitive reference guide for information on the causes, effects and alternatives available for dealing with this complex subject, providing an excellent resource on dust explosions. This book will serve as a foundational reference on the subject of dust explosions in the process industries. Also provided is detailed information of all phases of the hazard and control of a dust explosion. An invaluable reference.

-Jeff Nichols

As a resource to our valuable clients and readers, we provide the book review below from our colleague PUJAN AGNIHOTRI.

Mr. Agnihotri is an Associate Member of Society of Fire Protection Engineers (SFPE) & Member of National Fire Protection Association (NFPA), and research associate for www.IndustrialFirePrevention.com

Book Review: Dust Explosions in the Process Industries, 3rd Edition

Published by: Gulf Professional Publishing, An Imprint of Elsevier Science

ISBN 0-7506-7602-7, Hardcover, 705 pages, 2003

Author: Rolf K. Eckhoff, Professor of Process Safety Technology, The University of Bergen, Norway.

One of the major challenge in the field of fire protection & life safety engineering in process industries is Dust Explosion. Dust explosions are common & costly for a wide range of industries such as food, pharmaceutical, paper & petrochemical. Thus it is important to emphasis on in depth study of dust explosion to avert any higher intensity disaster like Sugar Dust Explosion at Imperial Sugar Factory, Georgia, February 7, 2008. This publication provides great deal of knowledge for all audience, from layman to fire protection & life safety experts, keenly interested in learning more about the dust explosion. Author has done an excellent job in compiling, from various sources, a large volume of material relating to dust explosion.

This publication helps reader to gain theoretical & practical knowledge about the origin, development, prevention & mitigation of dust explosions. It is divided in nine chapters with nearly 750 pages with tables, graphs, derivations & illustrative figures, for thorough understanding about the subject: Dust Explosion. The author has used more than 300 references for each chapter of this book. Eckhoff made some modifications in his third edition of book; mainly a chapter on design of electrical equipment used in areas containing combustible dust, re-organized final review chapter with nearly 400 new literature references from years 1997-2002 & broad distribution of sections from the original chapters one to seven.

First chapter is an overview about the origin, propagation, prevention, & mitigation of dust explosions. Author in this chapter discusses the nature of dust explosions, statistical records, importance of dust & dust cloud properties in explosion, methods involve in prevention & mitigation of dust explosion and their selection criteria. This chapter provides us basic understanding about dust explosions.

Second chapter describes the history of dust explosion accidents all over the world. The author discusses dust explosion in flour warehouse, silo plant, fish meal factory, large storage facilities, linen textile plant, coal dust plant, silicon powder grinding plant, slurry explosive factory, aluminum powder production plant. He covers dust explosion accident events in United States, United Kingdom, Norway, Germany, Canada, China, Russia & Sweden, from years 1785 to 1989. Author provided references to reports of more recent accidents in Chapter 9.

From chapter 3 the author starts exploring the different parameters affecting dust explosions. In this chapter, he discusses the explosive concentration of dust cloud through reentrainment & redispersion of deposited dust in air. He gives us a detailed understanding about the forces & strength of dust particles in powder or dust deposits and effects of gaseous medium on dust particle flow. He ends this chapter by providing methods for generating experimental dust clouds for research purpose.

Chapter 4 gives us information regarding flames movement in dust clouds. Author studies different parameters like burning velocities, flame thickness, quenching distances, rate of pressure rise (for closed vessel), explosible concentration, dimension of enclosure & temperatures for laminar, non- laminar & turbulent flame propagation of coal dust, organic dust, metal dust & miscellaneous dust particles, through various derivation. At the end of the chapter, author emphasizes detonation propagation in dust clouds in air.

In chapter 5, the author discusses the ignition of dust clouds & dust deposits. He talks about the self heating & self ignition of dust deposits, and dust clouds ignition from different sources like electric spark, mechanical rubbing, grinding, or impact & hot surfaces. Important parameters like minimum ignition temperatures, minimum ignition energy or minimum electric spark ignition energy, activation energy, minimum self-ignition temperature, are discussed in detail in this chapter.

Chapter 6 describes information regarding the vent sizing required for dust explosions. Author provides vent sizing methods used in Europe & United States. Further he provided derivation for calculating vent area in accordance to L/D (effective length/ diameter of the vessel), Pred (maximum pressure development in vented deflagration), Pmax (expected maximum pressure in vented explosions). Chapter 7 deals with laboratory scale tests for different properties of dust.

Chapter 8 research & development on dust explosions from years 1997 to 2002 in Chapter 9 are added in this edition of book. Chapter 8 discusses electrical apparatus usage in combustible dust containing area. Classification of areas, details of electrical apparatus design criteria, prevention of dust from potential ignition sources, intrinsically safe electrical apparatus are the topics discussed in detail in chapter 8. Chapter 9 concentrates on research & development in dust explosion field throughout the globe, with references for major dust explosion accidents in history.

Summarizing, I would recommend that this book is a key source of information for professionals dealing with combustible dust in their Industries.

-PUJAN AGNIHOTRI

Tennessee OSHA Offers Combustible Dust Training

messinabout@earthlink.net (John Astad) — Thu, 28 Jan 2010 22:35:00 +0000

TOSHA is planning the 2010 spring seminars

The Tennessee Occupational Safety and Health Administration has four upcoming combustible dust training courses in their Spring 2010 Seminar Schedule

Kingsport 04/16/2010 N.E.C.C.
Morristown 05/13/2010 TCCI
Smyrna 05/27/2010 TCCI
Jackson 06/10/2010 TCCI

TO REGISTER:
TCCI—(615) 256-5141, www.tnchamber.org
Northeast State Community College-N.E.C.C. —(423) 354-2570
* For TN Chamber of Commerce & Industry members, a lower price applies.

TOSHA Spring 2010 Seminar Schedule

It's the fires, stupid, Dust Explosion Precursors

messinabout@earthlink.net (John Astad) — Thu, 28 Jan 2010 14:42:00 +0000

Dust fire sends Elkhart plant employees into cold

It's the fires, stupid. Another combustible dust related fire, precursor to potential dust explosion. The NFPA Fire Analysis and Research Division report on U.S. STRUCTURE FIRES IN INDUSTRIAL AND MANUFACTURING PROPERTIES reported that annually 29% of the reported structure fires involved shop tools and industrial equipment. In 15% of fires, the leading area of origin was the process or manufacturing area or workroom. Additionally, leading items first ignited in 10% of fires was dust, fiber, lint, sawdust, or excelsior in industrial and manufacturing properties.

Stakeholder Comments OSHA Combustible Dust Rulemaking

messinabout@earthlink.net (John Astad) — Wed, 27 Jan 2010 15:28:00 +0000

Follow this link to the numerous stakeholder comments for the OSHA Advanced Notice of Proposed Rulemaking on the Regulations.Gov site Better yet, got to the "View by Docket Folder" tab and Sign up for Email alerts on the right side of the page.

Glass-Reinforced Plastic Production Process $90K OSHA Fine

messinabout@earthlink.net (John Astad) — Tue, 26 Jan 2010 23:13:00 +0000

OSHA's inspection found that combustible particulate solids, which were generated during trimming and repair operations, were not collected into an adequately designed dust collection system, were allowed to accumulate on machinery and surfaces, and were not adequately cleaned up to prevent such buildup.

via osha.gov

Housekeeping appears to be the major issue with this recent OSHA citation for combustible dust fire and explosion hazards at a Pawcatuck, Connecticut plant. Reviewing a MSDS sheet for glass-reinforced plastics (GRP) highlights that GRP is a compound based upon a mix of glass fibre in a polyester and styrene resin based mix.

The fire hazards of GRP arise when combustible dust from machining and fabrication operations of combustible particulate solids may be explosive if mixed with air in critical proportions in the presence of an ignition source. Additionally, during storage and handling the dust generated during normal manufacturing operations can represent both a health hazard and a fire hazard. Most importantly as the OSHA news release informs stakeholders to use dust control equipment at the point of generation in machining and sawing operations.

An often overlooked potential ignition source are powered industrial trucks where combustible dust mentioned in this news release was exposed to several potential ignition sources, including an LP gas-powered industrial truck. What class of forklift are you using at your facility? Is it rated for use in potentially explosive atmospheres? The recent status report on the OSHA Combustible Dust NEP emphasized that combustible dust citations for powered industrial trucks was the third most cited violation after hazardous communication and housekeeping violations.

The 5th Annual Industrial Fire, Safety, and Security Conference (IFSS) in Houston, Texas will be hosting a Full-Day Combustible Dust Workshop on February 2, 2010, which will provide information assisting stakeholders in addressing potential combustible dust ignition sources. During one segment of the workshop, guest speaker Robert Zuiderveld, General Manager of Business Development Americas from Pyroban Corp. will share with attendees specific information on the operation of powered industrial trucks in combustible dust. work environments. Information throughout the full day workshop will assist stakeholders in operating and maintaining a safe workplace in addition to achieving OSHA regulatory compliance.

Good housekeeping is a major issue at facilities with the generation of combustible dust from combustible particulate solids. Many facility managers and owners are not aware of the proper methods in cleaning up the dust. You just can't take a compressed air hose and start blowing down the area nor sweeping while unaware of the dust clouds that can be generated, which provide an explosive atmosphere similar to a flammable vapor cloud. Potential ignition sources in the process are inherent at many facilities. The safe and approved alternative is the use of an explosive-proof rated vacuum cleaner.

Guest speaker Bruce Gordon, Senior District Manager, from Nilfisk CFM will speak in the afternoon at the Combustible Dust workshop on "Proper Housekeeping and Explosion-Proof Vacuums Hazardous Locations" concerning good housekeeping that will minimize the likelihood of a combustible dust related fire or explosion in addition to achieving regulatory compliance. OSHA combustible dust citations are costly yet a catastrophic secondary dust explosion leveling the facility can be even more of problem. Do you know about the combustible dust hazards at your facility?

Resources
Glass-Reinforced Plastics (GRP)

Webinar - Combustible Dusts in Industrial Ventilation Systems - Jan. 27, 2010

messinabout@earthlink.net (John Astad) — Mon, 25 Jan 2010 20:37:00 +0000

the ACGIH^® Industrial Ventilation Committee is hosting this webinar aimed at educating the EH&S community on the importance of preparing for and preventing dust related incidents in industrial ventilation systems.

via acgih.org

Over 60% of combustible dust General Duty Clause citation examples in the recent OSHA status report on Combustible Dust National Emphasis Program were for industrial ventilation issues. Jonathan F. Hale, MS, founder and co-owner of Air System Corporation & Diagnostics and Marty Schloss, PE and General Manager, southeast operations, for KBD/Technic, Inc., a CECO Environmental Company will provide attendees to the webinar with strategies in dust control and ignition control in preventing combustible dust related fires and dust explosions in addition vital information in maintaining current and future regulatory compliance.

This webinar has been approved by the American Board of Industrial Hygiene (ABIH) for .42 ABIH (IH) Certification Maintenance (CM) Point (. This webinar qualifies for .15 BCSP (SP) Continuance of Certification (COC) Point for Certified Safety Professionals. Participants seeking CM and/or COC points must attend the live webinar or view the archive and submit a final exam and evaluation. Certificates of Completion will be issued in a timely manner after receipt and completion of these items.

Who Should Attend this Webinar?

* Industrial Hygienists
* Occupational and Environmental Health Professionals
* Safety Professionals
* Environmental Engineers
* Plant Managers

ACGIH® Members: $292.50 Nonmembers: $325.00
Test and Certificate of Completion Only:*** $25.00 per person

Potentially Explosive Atmospheres Global Requirements

messinabout@earthlink.net (John Astad) — Mon, 25 Jan 2010 18:06:00 +0000

DOWNLOAD Intertek WHITE PAPER:
"Potentially Explosive Atmospheres Requirements"
Complete the registration form with the link below to receive a free copy of Intertek's informative white paper, and learn more about the differences between North American and European rules.

via intertek-etlsemko.com

Excellent Intertek document that explains global classification systems of potentially explosive atmospheres such as flammable atmospheres of gases, mists, liquids, combustible dusts, and fibres. Describes important differences between the Zone (Europe and NEC505) and Division (NEC500) systems in hazardous (classified) locations?

Posted via web from ComDust

Industry Groups Responses to OSHA Rulemaking

messinabout@earthlink.net (John Astad) — Mon, 25 Jan 2010 15:31:00 +0000

National Cotton Council (NCC)-urges OSHA to "use caution" in regulating textile mills concerning combustible dust in factories.

National Solid Wastes Management Association (NSWMA) -September 2008, OSHA issued an advisory stating there was no history of combustible dust events at transfer stations, materials recovery facilities (MRFs) or landfills