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MFG Chemical Inc. Toxic Gas Release

Overview

On April 12, 2004, a runaway chemical reaction occurred during the first full-scale production batch of triallyl cyanurate (TAC) at MFG Chemical's Callahan Road facility in Dalton, Georgia. The reactor was over-pressurized. Highly toxic and flammable allyl alcohol and toxic allyl chloride were released into the nearby community. The release led to evacuation of residents and businesses. It also sent 154 people for decontamination and treatment. Environmental damage included an aquatic life kill downstream.

Incident Snapshot

Field Value
Facility / Company MFG Chemical, Inc.
Location Dalton, Georgia
Incident Date 04/12/2004
Investigation Status The CSB issued its final report on the accident at a news conference in Dalton, Georgia, on April 11, 2006.
Accident Type Reactive Incident / Toxic Chemical Vapor Cloud Release
Final Report Release Date 04/11/2006

What Happened

  • The operators loaded the dry-powder cyanuric chloride into the reactor on Friday, April 9, 2004.
  • The allyl alcohol isotainer arrived in the afternoon on Monday, April 12 and was parked adjacent to the reactor.
  • The operators pumped the entire quantity of liquid catalyst through the liquid feed line into the dry chemical already in the reactor.
  • They then transferred the allyl alcohol into the reactor by pressurizing the isotainer with nitrogen.
  • A short time after loading the allyl alcohol, the operators noticed that the reactor temperature had increased from 32° F to about 72° F.
  • Ten minutes later, the operators noted that the temperature had already climbed to 103° F.
  • The temperature continued to increase rapidly to 118° F.
  • Rapidly increasing pressure in the reactor caused the manway gasket to blow out.
  • Dense, white vapor immediately began to spray out of the manway.
  • The rupture disc blew open about 30 seconds later.
  • All seven personnel safely evacuated the facility as the vapor cloud rapidly expanded and began drifting off site to the north and east.
  • At 9:34 PM, a call informed the Whitfield County 911 Emergency Management Center that a chemical release involving allyl alcohol was occurring at the MFG Callahan Road facility.
  • Thirteen minutes after the MFG call to 911, the police department began evacuating residents.
  • The reactor continued venting toxic vapor for nearly eight hours and the evacuation order lasted more than nine hours.
  • Tuesday afternoon at 1:00 PM, more than 15 hours after the incident began, the reactor had cooled to 70°F and the reaction appeared to have ended.

Facility and Process Context

  • MFG Chemical operated two chemical manufacturing facilities in Dalton, Georgia, including the Callahan Road facility.
  • The Callahan Road facility was selected to manufacture triallyl cyanurate because it had a 4000-gallon, glass lined reactor (R4) and associated equipment needed for the chemical synthesis.
  • The process involved triallyl cyanurate (TAC) production using allyl alcohol, cyanuric chloride, and a catalyst.
  • The operator console was located approximately 20 feet south of the reactor on the mezzanine floor inside the building.
  • The reactor emergency vent released directly to the atmosphere and did not have a hazardous vapor/liquid containment system.
  • The planned use of allyl alcohol for the TAC process would result in a significant increase in the quantity of flammable liquid stored on site.
  • MFG developed the recipe in its laboratories and conducted some small batch testing before the incident.
  • MFG was unaware of the EPA Risk Management Program regulation according to the transcript, and the final report states MFG did not implement the EPA RMP or OSHA PSM program prior to receiving allyl alcohol.

Consequences

  • Fatalities: 0
  • Injuries: 154 people required decontamination and treatment for chemical exposure, including 15 police and ambulance personnel; one MFG employee sustained minor chemical burns; five residents required overnight hospitalization for breathing difficulties; five police officers required transport to the hospital for decontamination and treatment; the hospital treated thirteen police officers and four ambulance personnel for toxic chemical exposure.
  • Environmental Release: Highly toxic and flammable allyl alcohol and toxic allyl chloride were released into the nearby community; the runaway reaction released allyl alcohol and allyl chloride into the atmosphere and into a nearby creek; the Georgia Department of Natural Resources determined that a significant aquatic kill occurred as far as seven miles downstream from the facility.
  • Facility Damage: The manway gasket blew out; the rupture disc blew open; the reactor continued venting toxic vapor for nearly eight hours; the reactor had to be resealed with a new rupture disk, replaced manway gasket, and tightened clamps.
  • Operational Impact: The evacuation order lasted more than nine hours; more than 200 families were forced from their homes; the reactor vented toxic vapor for nearly eight hours; fire department response activities continued until the reactor was resealed.

Key Findings

Immediate Causes

  • There was a runaway reaction at the MFG facility during the TAC synthesis.
  • The runaway reaction resulted when operators added the entire quantity of each reactant, as well as the catalyst, to the reactor at once, and were then unable to control the reaction rate.
  • The runaway chemical reaction rapidly pressurized the reactor causing the manway seal to fail, and then activated the overpressure safety device.
  • MFG did not provide a hazardous vapor/liquid containment system on the reactor emergency vent.

Contributing Factors

  • MFG did not conduct an adequate evaluation of the reactive chemistry hazards involved in manufacturing triallyl cyanurate before attempting the first production batch.
  • Readily available technical literature, including specific TAC synthesis accident histories would have alerted them to the reactive chemistry hazards involved.
  • Lyondell Chemical (the allyl alcohol manufacturer) did not clearly communicate to MFG management or GPC that MFG would be required to implement the EPA Risk Management Program regulation, including conducting appropriate design reviews and preparing comprehensive emergency plans, before receiving the allyl alcohol shipment at the MFG facility.
  • MFG did not develop the comprehensive process hazards analysis, pre-startup review, and emergency response elements required by the OSHA PSM standard and the EPA Risk Management Program regulation.
  • MFG and GPC did not apply industry best practices for toll manufacturing such as those provided in Guidelines for Process Safety in Outsourced Manufacturing Operations (CCPS, 2000).
  • MFG did not share certain critical process safety information with GPC, and GPC did not ensure that MFG had addressed all hazards associated with the process before attempting to produce the first production batch.
  • The Whitfield County Emergency Response Plan did not include a community shelter-in-place or an effective evacuation plan, nor did it provide prompt notification to the affected residents and businesses.
  • The Dalton City and Whitfield County emergency response agencies did not have the hazmat team personal protective equipment and air monitoring devices needed to respond safely to the toxic chemical release.
  • The Dalton City Fire Department incident command did not direct all unprotected emergency response personnel to remain a safe distance away from the advancing toxic vapor cloud.
  • The incident command also allowed inadequately protected MFG employees to reenter the toxic vapor cloud.
  • The only decontamination station was more than five miles away from the perimeter of the evacuation zone, contributing to the spread of toxic material and exposure to additional personnel.
  • MFG employees conducted emergency response activities without the necessary procedures, training, or personnel protective equipment.
  • The State of Georgia has not established clear responsibility for oversight of the regulatory requirements contained in the Emergency Planning and Community Right-to-Know Act (EPCRA), and did not identify deficiencies in the Whitfield County Emergency Operations Plan.
  • The process development work failed to examine exothermic reactions, so MFG did not learn of the runaway potential of their process system.
  • MFG did not have a hazardous chemical collection system on the emergency vent, such as a toxic vapor scrubber or liquid collection tank on the reactor.
  • MFG personnel did not control the reaction rate using closely controlled, slow addition of the chemicals during the batch process.
  • The final recipe contained no fill rate limitations or warnings.
  • The fire department incident command should have directed all emergency response personnel to remain a safe distance away from the advancing toxic vapor cloud.
  • The fire and police departments lacked the special equipment and training necessary to respond safely to a highly toxic liquid or vapor release.
  • The triage and decontamination procedures performed by the ambulance crews and the hospital staff did not effectively control the potential spread of toxic chemicals.

Organizational and Systemic Factors

  • MFG did not understand or anticipate the reactive chemistry hazards.
  • MFG did not make use of readily available literature on the hazards of reactive chemistry, or conduct a comprehensive literature search of the reactive chemistry specifically involved in manufacturing the product.
  • MFG did not perform a comprehensive process design and hazard review of the laboratory scale-up to full production before attempting the first production run.
  • MFG did not prepare and implement an adequate emergency response plan.
  • MFG did not train or equip employees to conduct emergency mitigation actions.
  • MFG did not implement the EPA Risk Management Program or the OSHA Process Safety Management program prior to receiving the allyl alcohol.
  • MFG and GPC did not apply industry best practices for toll manufacturing.
  • Whitfield County did not have an established LEPC.
  • Whitfield County developed the emergency plan with minimal involvement of the companies who handle hazardous chemicals within the county, and had not updated the plan to address changes in company hazardous material usage.
  • The agency assigned to perform the emergency activity did not develop all of the standard operating procedures cited in the EOP, such as community evacuation.
  • The city and county lacked effective methods to promptly alert the public and keep them informed during the emergency evacuation.
  • Emergency evacuation instructions were only in English, yet many of the residents primarily spoke Spanish.
  • The Georgia EPD did not review the Whitfield County Emergency Operations Plan.
  • The Georgia EMA review did not address the EPCRA elements.

Failed Safeguards or Barrier Breakdowns

  • The production batch procedure contained no chemical addition rate restrictions.
  • MFG did not anticipate that the reaction between the allyl alcohol and the cyanuric chloride was also highly exothermic and could generate significant heat.
  • MFG did not perform the necessary cooling system analysis for the primary reaction.
  • The chiller system was not set up to provide for easy adjustments.
  • The procedure did not contain any requirement for the employees to measure the allyl alcohol vapor concentration in the air.
  • Management had not purchased air-monitoring devices suitable for detecting allyl alcohol.
  • They did not purchase "Level A" personal protective equipment if the vapor concentration level necessitated its use.
  • MFG did not notify the fire department when the allyl alcohol arrived, so the fire department site visit did not occur.
  • The operator console was equipped to monitor only two process parameters; the reactor pressure was only available at a pressure gauge mounted on the reactor and was not possible to read from the console or the building door.
  • The fire department did not have appropriate toxic chemical monitoring devices, protective clothing, or a trained and equipped hazmat response team.
  • The fire department did not monitor the air for toxic vapor concentration in the area during the bucket placement activity.
  • The fire department four-gas monitor used throughout their response activities at the facility was not suitable for detecting hazardous concentrations of the toxic allyl alcohol.
  • The air and water monitoring for allyl alcohol performed by MFG was inadequate.
  • Monitoring did not begin until several hours after the release had started.
  • The only air sampling performed was near the MFG facility; there was no air sampling in the affected community.
  • The emergency response plan did not address the HAZWOPER Hazardous Materials Technician tasks.
  • The emergency response plan was not updated to address the TAC production activities.
  • There were no provisions for pre-emergency planning and coordination with outside parties.
  • It did not contain information concerning personnel roles, lines of authority, training and communication.
  • Emergency recognition and prevention information was incomplete.
  • There were no personnel decontamination procedures.
  • There was no discussion of personal protective equipment and emergency response equipment.
  • The Whitfield County Emergency Response Plan did not include a community shelter-in-place or an effective evacuation plan.
  • The Dalton City and Whitfield County emergency response agencies did not have the hazmat team personal protective equipment and air monitoring devices needed to respond safely to the toxic chemical release.
  • The only decontamination station was more than five miles away from the perimeter of the evacuation zone.
  • The 4-inch diameter rupture disc installed on the reactor was undersized.
  • The reactor vessel did not have a hazardous vapor/liquid containment system on the emergency vent.
  • The emergency vent on the reactor released the contents directly to the atmosphere; it did not safely capture the toxic vapor.

Recommendations

  1. 2004-09-I-GA-R1 — Recipient: MFG Chemical, Inc. — Status: Not specified. Summary: Develop written procedures that require a comprehensive hazard analysis of new processes, especially those involving reactive chemistry. Ensure the hazard evaluations address critical process controls, overpressure protection, alarms, and other equipment such as vent collection/containment devices to minimize the possibility and consequences of a toxic or flammable release.
  2. 2004-09-I-GA-R2 — Recipient: MFG Chemical, Inc. — Status: Not specified. Summary: Provide EPA Risk Management Program regulation and OSHA Process Safety Management program training to affected personnel to ensure that the facility understands the scope and application of each regulation, and implements all requirements prior to receiving and using covered chemicals.
  3. 2004-09-I-GA-R3 — Recipient: MFG Chemical, Inc. — Status: Not specified. Summary: Create a comprehensive emergency response plan and provide equipment and training that is appropriate to the duties assigned to employees in the event of an emergency.
  4. 2004-09-I-GA-R4 — Recipient: MFG Chemical, Inc. — Status: Not specified. Summary: Implement written tolling procedures using resources such as the CCPS book Process Safety in Outsourced Manufacturing Operations. Ensure effective communication between the toller (MFG) and client throughout the process development, completion of a detailed process hazard analysis, creation of emergency procedures, and dissemination to all parties who would be involved in emergency response situations.
  5. 2004-09-I-GA-R5 — Recipient: GP Chemical — Status: Not specified. Summary: Implement written procedures for tolling agreements using resources such as the CCPS book Process Safety in Outsourced Manufacturing Operations. Ensure that tolling agreements provide for direct GPC involvement in new process development, including the detailed process hazard analysis and emergency planning, and active participation in the first production run, as appropriate.
  6. 2004-09-I-GA-R6 — Recipient: Lyondell Chemical Company — Status: Not specified. Summary: Revise the applicable sections of the Allyl Alcohol Product Safety Bulletin, appendices, and web page, to emphasize the applicability of the EPA Risk Management Program regulation and OSHA Process Safety Management standard. Clearly identify the threshold quantity of allyl alcohol applicable to each regulation.
  7. 2004-09-I-GA-R7 — Recipient: Lyondell Chemical Company — Status: R7: Closed – Acceptable Action. Summary: Revise the customer site safety assessment process, clearly addressing both PSM and Risk Management Program applicability before shipping allyl alcohol to a new customer. Include a requirement to review the customer's program documents, including the (draft) RMP, and internal and external safety audit or assessment records. Require that appropriate Lyondell health, safety, and environmental personnel review the written customer safety assessment before approving the shipment of allyl alcohol.
  8. 2004-09-I-GA-R8 — Recipient: City of Dalton — Status: Not specified. Summary: Establish, equip, and train a hazardous materials response team. Work with the Whitfield County Emergency Management Agency to update the Emergency Operations Plan, clearly defining the roles and responsibilities of the response team.
  9. 2004-09-I-GA-R9 — Recipient: City of Dalton — Status: Closed – Acceptable Action. Summary: Revise fire department and police department procedures and training to clearly define facility and evacuation zone access control responsibilities when hazardous chemicals are involved or suspected in an emergency.
  10. 2004-09-I-GA-R10 — Recipient: Whitfield County — Status: Closed - Acceptable Action. Summary: Establish a Local Emergency Planning Committee to assist the Whitfield County Emergency Management Agency to develop site-specific agency emergency response plans and standard operating procedures, develop training programs and conduct drills for emergencies at fixed facilities, and educate the community regarding proper protective actions, such as shelter-in-place and evacuation procedures.
  11. 2004-09-I-GA-R11 — Recipient: Whitfield County — Status: Closed - Acceptable Action. Summary: Work with the City of Dalton, representatives from local facilities, and relevant community representatives to review and revise the Emergency Operations Plan to update the list of facilities handling hazardous chemicals, including those covered by the EPA Risk Management Program regulation, develop standard operating procedures addressing communication of emergency information, evacuation, and shelter-in-place, conduct community training and drills that involve operation of the emergency notification system and potential actions in the event of an emergency, and implement an automated community emergency notification system.
  12. 2004-09-I-GA-R12 — Recipient: Governor of the State of Georgia — Status: Not specified. Summary: Clearly designate and define the roles of the agencies responsible for ensuring compliance with all sections of the SARA Title III (Emergency Planning and Community Right-to-Know Act) including review of Local Emergency Response Plans and accompanying attachments, such as standard operating procedures.
  13. 2004-09-I-GA-R13 — Recipient: Governor of Georgia — Status: Closed – Acceptable Action. Summary: Designate a responsible agency and develop a system that will encourage and assist local authorities to obtain and use Risk Management Plans for those facilities that are required to develop this information to aid in the development of the site-specific emergency response plans.
  14. 2004-09-I-GA-R14 — Recipient: Synthetic Organic Chemical Manufacturers Association — Status: Not specified. Summary: Revise the SOCMA website to simplify locating the link to the CSB website www.csb.gov, such as adding a link in "More Resources" on the SOCMA home page. Ensure that the CSB website and the report Hazard Investigation: Improving Reactive Hazard Management, Report No. 2001-01-H can be easily located using the SOCMA website search engine.
  15. 2004-09-I-GA-R15 — Recipient: Synthetic Organic Chemical Manufacturers Association — Status: Not specified. Summary: Develop a ChemStewards Management System Guidance Module that addresses tolling, including the best practices described in the CCPS book Process Safety in Outsourced Manufacturing Operations, and emergency planning involving new products.
  16. 2004-09-I-GA-R16 — Recipient: Synthetic Organic Chemical Manufacturers Association — Status: Not specified. Summary: Develop a formal training module for the ChemStewards Management System Tolling Guidance Module and provide appropriate training to SOCMA member companies. Include in the training program a discussion on the tolling issues identified in the MFG report.

Key Engineering Lessons

  • Reactive chemistry hazards must be evaluated before attempting first production batches, especially during laboratory scale-up to full production.
  • Batch procedures for reactive systems need explicit chemical addition rate limits and controls to prevent runaway reactions.
  • Overpressure protection and emergency vent design must account for toxic and flammable release consequences, including hazardous vapor/liquid containment on emergency vents.
  • Cooling system capability and adjustability must be analyzed for the primary reaction before production.
  • Process monitoring must allow operators to observe critical parameters such as reactor pressure from the control location.
  • Air monitoring equipment must be suitable for the specific toxic chemical involved, and monitoring should begin promptly and extend beyond the facility boundary when community exposure is possible.
  • Toll manufacturing requires effective communication of process hazards, emergency planning, and process safety information between the toller and the client.
  • Emergency response planning must include shelter-in-place or evacuation procedures, decontamination arrangements, and appropriate PPE and training for responders.

Source Notes

  • Priority 1 final report was used as the primary authority for incident sequence, causes, consequences, and recommendations.
  • Priority 4 supporting transcript and recommendation status pages were used only to supplement or clarify details not contradicted by the final report.
  • Where documents differed, the final report terminology and findings were preferred.
  • All facts are limited to information explicitly stated in the provided source extracts.

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