5 Explosions Leading to Imperial Sugar Catastrophe

The Imperial Sugar Refinery explosion in February 2008 was not an isolated incident of dust explosions in manufacturing industries across the nation's heartland. In the three weeks prior to the Imperial Sugar catastrophe, starting with a quarter moon and ending with a new moon, five combustible dust explosions occurred on both sides of the Mississippi, in the states of Kentucky, Wisconsin, Minnesota, North Dakota, and Virgina resulting in three injuries.

Incidents Continue
Over the last three months since the Imperial Sugar Refinery explosion, the Combustible Dust Policy Institute has recorded 40 additional combustible dust related fires and explosions resulting in injuries and adverse economic damage to local communities.

Millions of workers in over 100,000 manufacturing establishments that process combustible particulate solids are on borrowed time concerning when and where the next combustible dust incident will happen. At the current average rate of one incident every other day, over 100 combustible dust explosions and fires will occur in the remaining eight months of 2008.

Lessen the Odds
Since combustible dusts are an inherent aspect of the manufacturing process theres no absolute method of totally preventing future combustible dust fires and explosions. Bearings will overheat, electrical charges will overcome the dielectric strength of air, and upsets will occur.

To lessen the odds of an incident occurring, preventative administrative and technical measures must be pursued. Additionally, the destructive effects of a dust explosion or fire can be mitigated with explosion ventilation panels, spark detection and suppression systems, in addition to isolation valves. Short term costs for such equipment is initially high yet in the long term valuable assets will be protected from total destruction.

For instance, 40% of the dust explosions that occurred in the three weeks prior to the Imperial Sugar Refinery explosion, had protective and mitigative equipment installed, which lessened the damaging effects of the dust explosion. Additionally, no injuries, fatalities or adverse economic impact occurred in these incidents.

Hazard Assessment
Today is not to late to throughly check all overhead surfaces in the facility for an accumulation of dust. Suspended ceilings that have not been sealed properly can be a deadly culprit in the accumulation of combustible dust, especially if an upset occurs in the plant. The aisles and passageways can be hospital clean. But what about overhead where cleaning and maintenance crews do not usually perform scheduled cleaning duties...sight unseen up above?

May is starting out fresh with no incidents occurring in the last 24 hours. Now the challenge is to get by the rest of the week without a damaging combustible dust fire or explosion occurring. If a facility hasn't done so yet, then now is the time for a hazard assessment of all working areas in the plant.

Are combustible dusts present? If so then find out what potential ignition sources are present. Just like the dust hidden above, hidden electrical charges accumulating and dissipating can be the precursor to combustible dust ignition. Is your process material of high resistivity? If so then now is the time for laboratory testing in determining the minimum ignition energy (MIE) of dusts that are present in the process line.

One Size Fits All?
This week, Congress in a House vote with much opposition, passed a general industry comprehensive combustible dust bill and the next step is a vote in the Senate. The White House with the backing of the Chamber of Commerce has publicly stated their opposition to as they call it, "one size fits all" bill and says President Bush will veto the legislation. How can it be said that this is a "one size fits all"? Especially immediately after the Imperial Sugar incident, 40 combustible dust explosions and fires have occurred in the wood, food, metal, plastic, rubber, chemical, and pharmaceutical industries.

The Combustible Dust Bill is preceding next to the Senate for vote and will insure all manufacturing industries institute preventative and mitigative measures in preventing the devastating effects of predictable future combustible dust related fires and explosions.

Controlled ComDust Explosion: Flash-Bang!

Until the horrific combustible dust explosion at Imperial Sugar Refinery over two months ago, most of the nation had no idea that seemingly harmless coffee creamer and sugar poured into a cup of coffee jump starting us with a morning java jolt could also create another type of jolt, yet devastating . Many of the same food products found on the aisles of the local grocery store have the explosive power of gunpowder when suspended and ignited in a confined space such as a manufacturing facility.

Information gathered from OSHA's National Emphasis Program on combustible dust in conjunction with the Chemical Safety Boards Combustible Dust Study provides a conservative glimpse of over 100,000 firms in the United States that utilize raw combustible particulate solids of wood, rubber, plastic, metals, food, chemicals, and pharmaceuticals, which could generate explosive atmospheres. When the manufacturing process begins, combustible dusts are generated. Military and police forces use the same physics of a dust explosion in fuel-air bombs that generate controlled dust explosions.

The United States military has been very successful with fuel-air thermobaric bombs hitting the enemy caves in Afghanistan with the Hellfire missile. Police SWAT teams also have an application for controlled combustible dust explosions with flash-bang grenades that utilize a mixture of aluminum and potassium perchlorate dust. Yes, this is the same dust thats caused many combustible dust explosions and fires in the metal and chemical process manufacturing industries over the past several decades.

Combustible dusts are commonplace occurrence in our daily lives; in the packages on the grocery store aisles, military arsenals, community police tactical equipment, in addition to the manufacturing process. Once an awareness of combustible dust is acknowledged, then the proper mitigative and preventative measure can be instituted. Just don't go hiding in any caves or get the SWAT teams upset, theres no mitigation there.

Explosion Suppression and Spark Detection

The 2008 Process Technology Expo International Conference to be held at the Donald Stephens Convention Center on the outskirts of Chicago on May 6-8 2008 is the extravaganza to attend concerning combustible dust explosion prevention and mitigation equipment. Exhibitors will be displaying new technologies that the process manufacturing industry utilizes in the prevention and mitigation of future preventable and predictable combustible dust incidents.

Since the tragic Imperial Sugar explosion there's been over 30 combustible dust fires and explosions throughout the United States. OSHA's Combustible Dust National Emphasis Program highlights nearly 70 North American Industrial Classification codes (NAICS) of over 63,000 firms that have frequent and/or high consequence combustible dust explosions/fires in addition to industries that may have potential for combustible dust explosions/fires

The Combustible Dust Policy Institute has localized an additional 47,000 (NAICS) firms that also have occurrences of combustible dust related fires and explosions. With over 110,000 firms potentially exposed to explosive atmospheres in the process manufacturing industries, its' crucial that proactive measures be instituted

Initially firms must conduct a risk analysis of their unique processes in determining if hazards exist. For a minor investment of several thousand dollars, commercial testing facilities can assist in determining the minimum ignition temperature, minimum ignition energy , minimum explosive concentration, and explosive severity of the dust generated in their process.

With the information obtained concerning the ignition sensitivity and explosion severity, plant management can plan on the technical mitigative and preventive measures to implement. Protective and mitigative equipment could include spark detection systems, spark suppression, mechanical isolation valves, explosion vent panels, in conjunction with a multipoint monitoring system.

The PTXi show in Chicago will have a diverse spectrum of combustible dust protection manufacturers exhibiting such equipment and answering technical questions that arise concerning specific applications in the thousands of process industries throughout the nation.

Hope to see you there.

Explosion Protection Resource

(OSHA) Combustible Dust National Emphasis Program (NEP)

2008 Process Technology Expo International Conference

North American Industry Classification System (NAICS)

Metal Combustible Dust Particle Size

Information in Material Safety Data Sheets concerning fire hazards of most combustible particulate solids and the combustible dusts generated in the manufacturing process is absent in most instances. The definition of a combustible dust as defined by NFPA 654 is:

"Any finely divided solid material that is 420 microns or smaller in diameter (material passing a U.S. No. 40 Standard Sieve) and presents a fire or explosion hazard when dispersed and ignited in air." The same definition is used for combustible metal dust in NFPA 484, Standard for Combustible Metals, Metal Powders, and Metal Dusts.

Additionally, OSHA's Safety and Health Information Bulletin (SHIB), "Combustible Dust in Industry: Preventing and Mitigating the Effects of Fire and Explosions," published in 2005 states:

"That one possible source for information on combustibility is the Material Safety Data Sheet (MSDS) for the material. In some cases, additional information such as test results will be available from chemical manufacturers."

But thats were the problem arises, MSDS's, don't have the vital fire and safety information concerning combustible dust and laboratory testing is very costly. It's highly advised to have testing conducted as soon as possible . Until the facility management completes testing there is one alternative that the Combustible Dust Policy Institute has found most helpful concerning metal combustible dusts in the fabricated metal product manufacturing industries when determining if finely divided solid material is 420 microns or smaller in diameter .

For example, Atlantic Equipment Engineers has provided on their website a metal product technical data reference for over 120 metal powders and compounds. While browsing the numerous metal powders its quite easy in determining the product size of many many powders used in industry. Any US Sieve Series and Tyler Mesh Size higher than 40 would rank the powder as a combustible dust .

For a helpful review of micron powder particle size in relation to mesh size, here is a helpful link:
ESPICorp Inc.

Hope that helps in clarifying particle size in determining if your metal dust is a combustible dust or not. Until then, as soon as possible schedule a testing of your process dust for ignition sensitivity and explosion severity.

Resources:
NFPA 484, Standard for Combustible Metals, Metal Powders, and Metal Dusts

Map Combustible Dust Explosions 2007 & 2006

Here are a few helpful links of Google Maps regarding combustible dust related explosions and fires during 2007 and 2006.The data included in the Google Maps was obtained from Chemical Safety Board incident data. The Combustible Dust Policy Institute did not start collecting incident data until after the Imperial Sugar Refinery dust explosion in February 2008.

Google Map 2007

Google Map 2006

Here at the Combustible Dust Policy Institute, we will continue to provide updated information on the extent of combustible dust incidents throughout the process manufacturing industries. With knowledge of the prevalence of such incidents, all stakeholders can take appropriate preventative measures in protecting life and property.

Dozens Combustible Dust Fatalities and Injuries Unaccounted

As H.R. 5522, the Combustible Dust Explosion and Fire Prevention Act bill moves to the House floor shortly, dozens of fatalities and injuries are unaccounted for. Legislators, governmental agencies, and industry trade associations only have a partial picture of the magnitude of the threat posed to the workplace by the hidden dangers of combustible dusts.

Over the past decade 14 documented fatalities and 47 injuries have occurred in two dozen combustible dust explosions and fires that were not included in the official 2006 Chemical Safety Board Combustible Dust Study. Many of the incidents were not cleared for public release due to pending court cases. With the passage of time this information now becomes available to the public through governmental databases.

Chemical Safety Board

The Chemical Safety Board has provided the public with an excellent service considering their limited annual budget of less than $10 million dollars. Most of the workplace accidents consisting of fires and explosions go uninvestigated by the CSB due to limited resources. Innovation combined with computer technology the agency provides helpful feedback to the workplace on root causes of accidents so they don’t occur again. Most helpful to the process industries are the DVD’s that are offered free of charge which are excellent safety training tools for veterans and newcomers to the industry.

As a federal independent investigative agency, the CSB is limited in breath and depth while conducting research on past incidents. Especially troublesome is the absence of central database with records of workplace accidents consisting of fires and explosions. Concerning the Combustible Dust Hazard Study, the CSB did not represent the data as complete or error-free. Especially since the combustible dust incidents were only a small sampling.

Recent Studies

Over the past two months, the Combustible Dust Policy Institute has completed cursory research on combustible dust explosions and fires and picked up were the CSB combustible dust studies ended. Over that past ten weeks since the Imperial Sugar Refinery explosion there have been over 30 combustible dusts related fires and explosions.

Hundreds of Incidents

Currently, many stakeholders both opponents and proponents of the proposed Combustible Dust Explosion and Fire Prevention Act, H.R. 5522, are under the assumption that there has been approximately 350 combustible dust fires and explosions since 1980. This is a very small sampling and a closer number would be approximately 3500 combustible dust explosions and fires over the last 28 years.

Either the earth, moon, sun, and planets were aligned in some unusual manner for the nearly three dozen combustible dust incidents to occur over the past ten weeks or now we have a better picture of the extent of the complex subject of combustible dust incidents occurring in the nation’s manufacturing process industries.

Resources

Chemical Safety Board

OSHA Integrated Management Information System database