Carbide Industries, LLC. Electric Arc Furnace Explosion March 21, 2011 (Louisville, KY) “Normalization of Deviance - a new normal to routine”
Byung Kyu Kim Graduate Research Assistant Mary Kay O’Connor Process Safety Center Steering Committee Meeting Case Study March 28, 2013 Overview Carbide Industries, LLC. • Mainly produces calcium carbide – 120,000 tons of molten calcium carbide per year • Employs about 160 workers in operations, maintenance, and administrations • Operates 50 MW electric arc http://www.carbidellc.com/ furnace (EAF) • Electric arc furnace (EAF) over-pressured and emitted hot materials on March 21, 2011 – Two workers were killed and two were injured
2 Product Description Calcium carbide
• Chemical formula: CaC2
• Reaction: CaO + 3C → CaC2 + CO – Lime (calcium oxide, CaO) is premixed with coke (carbon, C) and heated to 4100 ºF in EAF – By-product: carbon monoxide, hydrogen (from coke) • Gray to black solid in room temperature, supplied as granules or powder • Widely used in steel industry and raw material for acetylene produce
http://www.carbidellc.com/About/aboutquality.html
3 Process Description Electric Arc Furnace (EAF) • Pre-mixed feed enters the EAF through feed chute that is heated by three electrodes – Continuous process and only shut down for periodic maintenance • By-product gases are removed through vent system • Process controlled by monitoring the flames created from gases exiting furnace • Cooling water system installed to prevent other contacting metal from overheating www.csb.gov
4 Incident Description • At about 5:40 pm on March 21, 2011, EAF violently overpressured, ejecting debris, hot gases and molten products at near 3800 ºF • A large explosion occurred at furnace, followed by two to three more overpressure events – Two employees inside control room with double-pane reinforced glass window died – Two employees working around furnace suffered minor burn
www.csb.gov
5 Incident Analysis Codes & Standards • NFPA 86 Standard for Ovens and Furnaces – No operational requirements directed to EAF, such as safety devices, interlocks and safety distances to occupied buildings • Kentucky Standards of Safety – Established requirement for design and construction of various facilities, however, requires conformance to NFPA 86
Regulatory Oversight • Carbide Industries is not a OSHA regulated facility • Various elements could have covered if PSM standard had been applied – Incident investigation: lesson learned from previous near misses – Mechanical integrity: timely replacement of furnace elements – Training: practices and procedures that could have prevented or lessened consequence of explosion
6 Incident Analysis Water cooling system • Multiple leaks and holes found in water cooling system • 26 work orders submitted for water leaks in last four months prior to incidents • Only temporary maintenance had been done without further investigation on root causes – Applied commercially available powders used to repair leaks in steam boilers
www.csb.gov
7 Incident Analysis Facility Siting • Occupied control room located on 12 feet away from furnace • NFPA 86 requires the furnace to be located to protect personnel and building from fire & explosion hazards – No further clarification on locating furnaces • Location of occupied building had not been evaluated
www.csb.gov 8 Incident Analysis Normalization of Deviance • Gradual shift in what is regarded as normal after repeated exposure to deviant behaviors – Abnormal events become tolerable, and new normals become routine events
Carbide Industries, LLC. • Smaller scale overpressure occurred for last 20 years – 1991: overpressure blew of control room window – 2004: reinforced window blew off, replaced by double plane reinforced glass • No proper investigation was conducted to identify and address potentials for higher consequence incidents – Since the root causes were not identified, occurrence became normalized
9 Incident Analysis Normalization of Deviance
“About 5:00 o’clock … we heard the – heard the furnace – you know – do a little booming – you know. And I didn’t think much – much of it, just the sound of it and stuff – you know. It – it sounded normal when it does it. And then, it was a little while after that, it went off again, and it was – it wasn’t normal.” -CSB interview with a Carbide employee
•Ignore warnings from alarms, near-misses, lower severity? –Fails to control hazards with high severity incidents
10 Normalization of Deviance
• NASA Columbia Disaster “…No debris shall emanate from the critical zone of the (Feb, 2003) External Tank on the launch – Foam shedding, debris impacts, pad or during ascent…” and thermal protection system Ground System Specification (TPS) tile damages came to be Book – Shuttle Design regarded as only a routine Requirements maintenance concern after 133 missions – Each successful mission reinforced perception of tolerance to failure of components (unavoidable, unlikely to jeopardize safety) – Based upon the rationale that “nothing bad has happened yet” Foam debris after impact on Columbia’s left wing (NASA) Report of Columbia Accident Investigation Board, Volume I, NASA (2003)
11 Normalization of Deviance
• Bhopal MIC Release (Dec, 1984) Bhopal, India – Protection system disabled/not designed properly (cooling system, flare system, vent gas scrubber, water deluge system, instruments) • Texas City Explosion (Mar, 2005) Texas City, TX – “broken alarms, thinned pipe, chunks of concrete falling, bolts dropping 60 ft and staff being overcome with flumes” Telos (Jan, 05) • Buncefield Explosion (Dec, 2005) Hertfordshire, UK – Clear signs that high-level switch was not fit for purpose was ignored • Macondo Explosion (Apr, 2010) Gulf of Mexico, US – Concerns were not addressed properly from contractors on equipment designs and operation practices
12 Normalization of Deviance
• High-Reliability Organization Theory – Four elements recognized by the Columbia Accident Investigation Board as “extreme useful” 1. Commitment by political and organizational leaders to make safety a very high priority, and communicate message clearly and effectively 2. Redundancy within and between organizations, such as administrative system, to limit the failings of people within 3. Create “culture of reliability”, which encourages and decentralize authority to lower levels with confidence that subordinate will take appropriate actions with regard to safety issue 4. Develop value of organizational learning, which may promote a learning process of “sophisticated trial and error”
Heimann, L. (2005) Repeated failures in the management of high risk technologies, European Management Journal, 23, 105-117.
13 Normalization of Deviance
• CCPS Recommendations – Do not allow operations outside established safe operating limits without detailed risk assessments – Do not tolerate willful, conscious, violation of an established procedure without investigation, or without consequences for persons involved – Train staffs to strictly adhere to safety policies and practices even when supervision is not around to monitor compliances – Determine practices or conditions that would have been deemed unacceptable a year or two ago
CCPS (2005) Lessons from the Columbia disaster. Presented Nov 15, 05. American Institute of Chemical Engineers
14 Recommendations
• National Fire Protection Association – Evaluate and develop standard that defines safety requirements for electric arc furnace • Safety instrumentation and controls • Mechanical integrity and inspection programs • Siting analysis to ensure occupied areas are adequately protected • Carbide Industries – Modify design and procedures for EAF and related structures – Implement mechanical integrity program – Preventive maintenance (periodic inspection, timely replacement)
15 References
• CSB, Carbide Industries, LLC, Louisville, KY, Electric Arc Furnace Explosion, 2013, Chemical Safety Board • CSB: http://www.csb.gov/investigations/detail.aspx?SID=103&Type=2&pg=1&F_All=y (accessed Feb, 2013) • Carbide Industries, LLC.: http://www.carbidellc.com/ (accessed Feb, 2013) • NFPA: http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=86&cookie%5Ftest=1 (accessed Feb, 2013) • 815 KAR 10:060. Kentucky standards of safety: http://www.lrc.ky.gov/kar/815/010/060.htm (accessed Feb, 2013) • REPORT: Carbide Industries ignored warning signs and tolerated failure, http://www.wdrb.com/story/21036898/report-released-on-fatal-carbide-industries-explosion (accessed Feb, 2013) • Bhopal Incident: Mannan, S. (2005). Lees' Loss Prevention in the Process Industries, Volumes 1-3 (3rd Edition). Elsevier. • Buncefield Incident: COMAH, Buncefield: Why did it happen? The underlying causes of the explosion and fire at the Buncefield oil storage depot, Hemel Hempstead, Hertfordshire on 11 December 2005 • Texas City Incident: CSB Investigation Report, Refinery Explosion and Fire (15 killed, 180 injured) BP Texas City, Texas, March 23, 2005 • Macondo Incident: Deepwater Horizon Accident Investigation Report, BP, September 8, 2010 • CCPS (2005) Lessons from the Columbia disaster. Presented Nov 15, 05. American Institute of Chemical Engineers • Heimann, L. (2005) Repeated failures in the management of high risk technologies, European Management Journal, 23, 105-117. • Report of Columbia Accident Investigation Board, Volume I, NASA (2003)
Acknowledgements
Dr. M. Sam Mannan Dr. Victor Carreto
All Members of MKOPSC
Thank You
Any Questions? Comments?