West Pharmaceutical Services explosion

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The West Pharmaceutical Plant explosion was an industrial disaster that occurred on January 29, 2003 at the West Pharmaceutical Plant in Kinston, North Carolina, United States. Six people were killed and thirty-six people were injured when a large explosion ripped through the facility, and two firefighters were also injured in the subsequent blaze.[1] The disaster occurred twelve years and 170 miles (274 km) from the 1991 Hamlet chicken processing plant fire, America's second-worst industrial disaster.[2]

Contents

[edit] Background

The West Pharmaceutical Plant was owned by a company called West Pharmaceutical Services,[3] and opened in the early 1980s.[2] The plant employed 255 people with wages of between $12 and $14, some of the highest in the area.[2] The facilitiy's purpose was trifold; to manufacture syringe plungers, to manufacture intravenous components and as a rubber compounding facility.[3]

In October 2002 an inspector found a total of 22 "serious violations" at the plant, but said that these were routine findings for the large number of industrial premises in North Carolina.[2] West were fined $10,000 as a result.[2]

[edit] Event

The plant was ripped apart by a violent explosion. Witnesses reported hearing "a sound like rolling thunder", as what was later determined to be a chain reaction of explosions rapidly propagated.[4] The shock wave broke windows at distances of up to 1,000 feet (330 m) away, and propelled debris as far as two miles (2 km) away, some of which started additional fires in wooded areas at this distance.[5][1] The blast could be felt 25 miles away.[1] A large fire raged for two days at the site of the plant itself.[1] Damage to the plant was estimated to be in the region of $150 million.[5] One half of the 150,000 square-foot (13,935 m²) plant was completely destroyed.[6]

[edit] Investigation

The investigation initially focused on two separate possibilities: a failure of a newly-installed gas line, and a large rubber dust explosion.[2] However, from an early stage the theory that was pursued was the dust explosion theory.[5] Within twenty-four hours of the explosion the Chemical Safety and Hazard Investigation Board, who conducted the investigation, had determined from eyewitness interviews that the explosion originated in an area known as the Automated Compounding System.[5] This was a synthetic rubber processing system, and was for the mixing, rolling, coating, and drying of a type of rubber called polyisoprene.[5] The process adds oils and fillers to the material, as well as creating significant quantities of dust.[5] Therefore, the working theory from an early point was the rubber dust explosion theory.[5]

One particular machine was identified. It coated strips of rubber by dipping them in Acumist, which is a finely powdered grade of polyethylene and is combustible.[6] This machine had operated for 24 hours a day, five or six days a week, since 1987.[6] The space around the machine, including a suspended ceiling three feet (0.9 m) above the machine, were regularly cleaned by the factory's maintenance personnel.[6] However, they were unaware that ventilation systems within the room pulled the dust up into the ceiling, where an accumulation 0.25 to 0.5 inches (6.3 to 12 mm) thick had gathered.[6] However, it is known that several weeks prior to the accident, maintenance personnel did notice a thick layer of dust coating surfaces above the suspended ceiling, but failed to realize the imminent danger posed.[4]

The investigation determined that the explosion occurred when something disturbed the dust, creating a cloud, which then ignited.[6] The investigation was unable to determine what disturbed the dust or what ignited it,[6] due to the extremety of the damage suffered at the plant.[7] However, it is known that the machine had suffered multiple internal fires, including one that was powerful enough to blow off the mixer door.[8] Four other theories were developed regarding possible causes: a batch of rubber that overheated and ignited; an electrical ballast or light fixture that ignited accumulated dust; a spark caused by a possible electrical fault; or ignition of dust in a cooling air duct feeding an electric motor.[7]

It was determined that West had in their possession material safety data sheets (MSDSs) supplied by the powder manufacturer that warned of the danger of such explosions, but did not refer to them. Instead, they relied on the MSDS supplied by Crystal Inc. PMC, who supplied West with a polyethylene-water slurry. However, this neglected to mention the hazard posed by dust as it was not thought to be hazardous once the slurry had dried.[7]

The final report into the disaster was highly critical of West, saying that the four "root causes" of the disaster were West's inadequate engineering assessment for combustible powders, inadequate consultation with fire safety standards, lack of appropriate review of MSDSs, and inadequate communication of dust hazards to workers. It also criticised West for not investigating a minor incident in which dust ignited during welding, by which West could have realised the imminent danger posed by the dust.[7]

[edit] Recommendations

The final report made a number of recommendations to prevent a recurrence. A brief summary of each one is provided below:

  • North Carolina's Building Code Council should adopt NFPA 654, a set of building codes which controls operations in environments involving large quantities of combustible dust. In particular, it limits combustible dust accumulations to 1/32 of an inch.[7]
  • North Carolina's Department of Labor should identify industries at risk of future explosions, and educate people involved with these industries about the potential risk of dust explosions.[7]
  • North Carolina fire and building code officials should be trained to recognise the hazards posed by flammable dust.[7]
  • West Pharmaceusticals should improve its material safety review procedures, revise its project engineering practices, communicate with its workers about combustible dust hazards, and follow safety practices contained in NFPA 654 at all company facilities that use combustible powders.[7]
  • Crystal inc. PMC should modify their MSDSs to discuss the hazards posed by potential dust explosions.[7]

[edit] Aftermath

Less than a week after the disaster, the local county commission voted to donate $600,000 to West to rebuild.[2] A local landlord also offered temporary free office space to company executives.[2]

On February 20, 2003 a private memorial service entitled "A Service of Healing and Remembrance" was held at Lenoir Community College, Kinston, for surviving plant employees and their families.[9]

One year into the investigation, the disaster, coupled with the CTA Acoustics fiberglass insulation manufacturing plant explosion and the Hayes Lemmerz automotive parts plant explosion, with death tolls of seven and one respectively, which also involved dust explosions in 2003, prompted the Chemical Safety and Hazard Investigation Board (CSB) to conduct a study into the number and severity of dust explosions throughout the United States over several decades. The boards chairman, Carolyn Merritt, described the accidents as collectively raising "safety questions of national significance... Workers and workplaces need to be protected from this insidious hazard." The purpose of this study was to review how the dust explosion hazard was controlled by regulatory codes, standards, and good operating practices, and also compared the US to other countries solutions to the same problem,[10] in order to produce a review of potential initiatives to reduce the occurrence of industrial dust explosions.[1]

In 2004, The Science Channel broadcast a documentary about the explosion and subsequent investigation, entitled "Failure Analysis: Dust Explosion". The CSB expressed their approval of the documentary, saying that it would "help spread the word about the dangers of combustible dust in the workplace".[11]

[edit] References

  1. ^ a b c d e In Final Report on West Pharmaceutical Explosion, CSB Finds Inadequate Controls for Dust Hazards, Calls on North Carolina to Strengthen Fire Code on Combustible Dust - Chemical Safety and Hazard Investigation Board press release - Obtained April 25, 2007.
  2. ^ a b c d e f g h Lessons from a factory fire - The Christian Science Monitor - Obtained April 18, 2007.
  3. ^ a b West Pharmaceutical Services Provides Update on Plant Explosion - findarticles.com - Obtained April 20, 2007.
  4. ^ a b Preliminary Findings Confirm Blast at West Pharmaceutical Services in Kinston, NC, Was a Dust Explosion Fueled by Plastic Powder Used in Manufacturing - Chemical Safety and Hazard Investigation Board Press Release - Obtained April 21, 2007.
  5. ^ a b c d e f g CSB Team Focuses on Rubber Blending Area in North Carolina Explosion - Chemical Safety and Hazard Investigation Board Press Release - Obtained April 21, 2007.
  6. ^ a b c d e f g Federal board urges North Carolina make NFPA 654 mandatory after fatal plant explosion - NFPA - Obtained April 21, 2007.
  7. ^ a b c d e f g h i In Final Report on West Pharmaceutical Explosion, CSB Finds Inadequate Controls for Dust Hazards, Calls on North Carolina to Strengthen Fire Code on Combustible Dust - CBS press release - Obtained April 25, 2007.
  8. ^ CSB Team Finds Several Possible Sources of Explosive Dust at Destroyed N.C. Medical Plant - Chemical Safety and Hazard Investigation Board Press Release - Obtained April 21, 2007.
  9. ^ West Pharmaceutical Services Announces Kinston Plant Memorial Service and Kinston Employee Fund. - Goliath - Obtained April 21, 2007.
  10. ^ CSB Considers National Safety Issues as West Pharmaceutical Investigation Continues One Year after Explosion - Chemical Safety and Hazard Investigation Board press release - Obtained April 25, 2007.
  11. ^ The Science Channel to Broadcast Documentary on CSB Dust Explosion Investigation Nov. 5, 2004, 9 p.m. - Chemical Safety and Hazard Investigation Board press release - Obtained April 28.

[edit] External links