Cause of Bayer Cropscience explosion-findings released
Here’s an update on the Bayer Cropscience explosion at it’s Institure, W. Va facility. The US Chemical Safety and Hazard Investigation Board has released preliminary findings related to the cause of the explosion, that resulted in fatalities and evacuation of some residents in the surrounding areas. Read about the original incident here.
For those of you who are already aware of the incident, the US Chemical Safety and Hazard Investigation Board announced that it would conduct a public hearing on the incident on April 23, 2009 at which members of the public were invited to participate. There were several attempts by vested interests to scuttle this hearing and obfuscate the findings, under the disguise of “national security”. Thankfully these moves were successfully stalled and the hearing did take place.
However the preliminary findings were released just before the hearing actually took place. This is a summary based on information posted on the US Chemical Safety and Hazard Investigation Board website.
The explosion on August 28, 2008 in Institute, W. Va., occurred as a runaway reaction created extremely high heat and pressure in a vessel known as a residue treater, which ruptured and flew about 50-feet through the air, damaging several process vessels, twisting steel beams, and breaking pipes and conduits. Two operators died as a result.
Eight workers reported symptoms of chemical exposure, including aches and intestinal and respiratory distress, including two employees of the Norfolk Southern railway company and five Tyler Mountain, West Virginia volunteer firefighters, and an Institute, West Virginia volunteer firefighter. Two sought treatment at a hospital emergency room the next day, were treated, and released.
Releasing preliminary findings prior to a planned CSB public meeting in Institute, CSB Board Chairman John Bresland said, “Our investigation is continuing, but we are here to brief the community about what we know at this point.”
As in any such accident, there were a combination of several factors that acted together to cause the accident. Here are a few of them, if you know of any more please respond via the Comments below.
1. Replaced DCS: The control system for the Methomyl production plant was upgraded from a Honeywell system to a new Siemens system, but apparently the operators were inadequately trained on the new system. Since all screens and commands were different, during the emergency many experienced operators also could not respond quickly.
2. Startup after a long shutdown: The plant was starting up after a long shutdown. Many accidents that have occurred in chemical and process industries happened just after a major maintenance and shutdown, during startup.
3. Poor process design. The residue treater which had a heater that was supposed to break down Methomyl was undersized and incapable of handling normal loads. This caused inadequate decomposition of Methomyl.
4. Bypassing of Safety Interlocks: As a workaround to the problem above operators routinely bypassed safety interlocks.
5. Worker fatigue: Operators normally worked 12 hours a day and sometimes 18 hours. Hardly conducive to acting lightning fast in emergencies like this.
Some other factors, but which are not in the CSB reports, but gleaned from other sources on the web state that
6. Non functional toxic gas monitors: Apparently many (or all?) of the toxic gas monitors were dysfunctional. They were not hooked up to any system at all. There were none installed on the western side of the site and the wind direction that day was towards the west.
7. Non functional video cameras: There were video cameras, but not connected to any monitoring system.
However the accident could have been worse as the explosion took place right next to a tank containing the deadly chemical Methyl Isocynate (MIC for short) that caused the deaths of thousands of people in Bhopal, India several years ago when it leaked from a Union Carbide plant.
Major fire at North Star Foods plant forces evacuations
A major fire broke out at the North Star Foods plant in St.Charles, Minn on Friday, April 17, 2009, forcing the evacuation of nearly 3000 residents, reports the Winona Daily News. A huge fire at the meat processing plant with a towering plume of black smoke, visible nearly 10 miles away, caused panic in the area. The news that anhydrous ammonia tanks inside the facility could explode only added to residents’ fears.
The fire started in a section of the building that houses conveyor-belt ovens used to cook poultry, beef and pork, said Mark Eads, North Star’s plant manager. Eckles said the fire may have started near a rooftop refrigeration unit. An official cause is yet to be determined. The state fire marshal’s office is investigating the cause of the blaze.
Apparently the firefighters could manage to douse out most of the flames by evening and release the ammonia by opening the valves on the tanks, reducing the risk of an explosion.
However the disaster has resulted in a many of the town’s residents uncertain about their economic future, as the plant is a large part of the local economy, both as a customer of services as well as an employer. Nearly three fourths of the plant appears to be gutted by the blaze. The plant has been in operation since about 1971.
How to classify hazardous areas?
This is the question that many people ask themselves. There are so many standards and practices, so different from each other. You have the Class, Division & Group classification in North America and the Zone and Group system in Europe, Asia and Australia. The NEC also talks about Zones in Article 505 and there is the IEC-Ex harmonization scheme. To make matters more interesting, we have ATEX in the EU.This all adds to the confusion.
On the other hand, all of us agree that a lack of understanding of how to carry out area classification, can result in a disaster at worst, or at best, a huge lifecycle cost. How? If a poor area classification scheme results in a hazardous area marked as non-hazardous, then that is an invitation to a disaster. Similarly, overzealous area classification can result in large swathes of your plant marked as hazardous, when in reality they need not be. If a typical life of a process plant is about 30 years then you have 30 years of increased maintenance and operations costs, that will fly under the radar of most managers. So it will bleed your plant dry without anybody noticing it. Great, isn’t it?
So here’s an answer. Get your copy of the new Practical Guide to Hazardous Area Classification, recently released by Abhisam Software. It costs just $27, but is worth many more times in the value that it offers. In addition to a compilation of all the well known standards and systems of classification, it has practical examples from working process plants including drawings and photos, to give you a unique perspective on Area Classification. And if you do not want to spend even the $27 on it, you can get it free, if you buy the Hazardous Area Instrumentation course from them, but I think it’s only for a limited time.
You can drop your feedback/review of this book in the comments section.
If you would like to know more about how proper hazardous area classification is important, you can refer to a blog post on this blog earlier here.
Hot work without a gas test-when will people ever learn?
Another accident has been reported due to negligence and lack of an understanding of hazardous materials and their properties. Fortunately there have been no fatalities, only two injuries, but they are severe and the victims have been hospitalized, reports the Merced Sun Star, in a news item dated April, 02, 2009.
The two injured men were workers in a produce plant (A.V.Thomas Produce, 3900 Sultana Drive, Atwater, Merced County, CA ), who were using an Acetylene blowtorch on a fuel tank. They were trying to loosen a compression bolt on the fuel tank, when it exploded. Common safety procedures apparently were not followed. The tank exploded, causing second- and third-degree burns to 30 and 50 percent of the men’s bodies, according to Cal Fire Battalion Chief Kevin Lawson. Read the full story here.
It is very clear what caused the explosion. It is not the usage of an acetylene torch or the presence of volatile flammable materials near a naked flame, it was IGNORANCE that caused the explosion. A basic safety training in the hazards of volatile organic compounds like gasoline or diesel would have helped. There was no gas test to detect %LEL near the fuel tank, nor any “hot work” permit system.
When will we ever learn?
