U.S. CHEMICAL SAFETY AND HAZARD INVESTIGATION BOARD

INVESTIGATION REPORT 

REPORT NO. 2004-09-I-GA 

APRIL 2006 

TOXIC CHEMICAL VAPOR CLOUD RELEASE

(154 Treated, Five Hospitalized for Toxic Chemical Exposure) 

 MFG CHEMICAL, INC. 

 DALTON, GEORGIA

APRIL 12, 2004

KEY ISSUES: 

• REACTIVE CHEMICALS PROCESS DESIGN 

• PROCESS SCALE-UP

• EMERGENCY PLANNING AND RESPONSE

 April 2006 

Abstract 

This report examines a toxic chemical release. On April 12, 2004, a runaway chemical reaction during 

the production of triallyl cyanurate at MFG Chemical, Inc. (MFG) in Dalton, Georgia, released highly 

toxic and flammable allyl alcohol and toxic allyl chloride into the nearby community, forcing the 

evacuation of more than 200 families. One worker received chemical burns and 154 people, including 15 

police and ambulance personnel, required decontamination and treatment for chemical exposure. This 

report makes recommendations to the companies involved in the incident, as well as the local, county, and 

state agencies in charge of preparing emergency responses to chemical releases. 

The U.S. Chemical Safety and Hazard Investigation Board (CSB) is an independent Federal agency 

whose mission is to ensure the safety of workers and the public by preventing or minimizing the effects of 

chemical incidents. The CSB is scientific investigative organization; it is not an enforcement or 

regulatory body. Established by the Clean Air Act Amendments of 1990, the CSB is responsible for 

determining the root and contributing causes of accidents, issuing safety recommendations, studying 

chemical safety issues, and evaluating the effectiveness of other government agencies involved in 

chemical safety. No part of the conclusions, findings, or recommendations of the CSB relating to any 

chemical incident may be admitted in evidence or used in any action or suit for damages arising out of 

any matter mentioned in an investigation report (see 42 U.S.C. § 7412[r][6][G]). 

The CSB makes public its actions and decisions through investigation reports, summary reports, safety 

bulletins, safety recommendations, special technical publications, and statistical reviews. More 

information about the CSB is at www.csb.gov. 
 April 2006 

i 

Contents 

EXECUTIVE SUMMARY ..........................................................................................................................1

1.0 INTRODUCTION ...........................................................................................................................3

1.1 Background......................................................................................................................................3

1.2 Investigative Process........................................................................................................................4

1.3 Key Findings:...................................................................................................................................6

1.4 Companies Involved ........................................................................................................................8

1.4.1 MFG Chemical, Inc. ...........................................................................................................8

1.4.2 GP Chemical.......................................................................................................................9

1.4.3 Lyondell Chemical Company ...........................................................................................11

1.5 Chemical Characteristics ...............................................................................................................12

1.5.1 Allyl Alcohol ....................................................................................................................12

1.5.2 Cyanuric chloride..............................................................................................................13

1.5.3 Allyl Chloride ...................................................................................................................13

1.6 Triallyl Cyanurate Process Development ......................................................................................14

1.6.1 GP Chemical Studies ........................................................................................................14

1.6.2 MFG Studies.....................................................................................................................15

1.7 Pre-Startup Hazard Planning..........................................................................................................18

1.7.1 Lyondell Allyl Alcohol Product Stewardship...................................................................18

1.7.2 MFG Safety Program........................................................................................................20

1.8 Process Controls and Cooling System ...........................................................................................23

1.8.1 Process Instruments ..........................................................................................................23

1.8.2 Reactor Cooling System ...................................................................................................23

1.9 Chemical Addition Sequence.........................................................................................................24
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1.9.1 Dry Chemical Loading......................................................................................................24

1.9.2 Allyl Alcohol Delivery and Connection to the Process ....................................................25

1.9.3 Final Chemical Addition...................................................................................................27

2.0 INCIDENT DESCRIPTION..........................................................................................................28

2.1 Process Upset.................................................................................................................................28

2.2 Facility Evacuation ........................................................................................................................29

2.3 Emergency Response.....................................................................................................................29

2.3.1 First Responder Actions....................................................................................................29

2.3.2 Initial On-Site Response Activities...................................................................................31

2.3.3 Community Evacuation ....................................................................................................34

2.3.4 Triage of Injured Individuals ............................................................................................35

2.3.5 Toxic Chemical Decontamination and Treatment ............................................................35

2.3.6 Mitigation and Containment of the Toxic Vapor Cloud...................................................36

3.0 INCIDENT ANALYSIS................................................................................................................39

3.1 Process Chemistry Analyses ..........................................................................................................39

3.1.1 Raw Materials Purity Testing ...........................................................................................39

3.1.2 Thermal Stability Studies..................................................................................................39

3.1.3 Reaction Decomposition Products Analyses ....................................................................44

3.2 Vapor Cloud Plume Model ............................................................................................................45

3.3 Process Design and Scale-up .........................................................................................................45

3.4 Chemical Addition Rate Control ...................................................................................................46

3.5 MFG Emergency Management......................................................................................................47

3.5.1 Reporting and Notifications..............................................................................................47

3.5.2 Risk Management Program...............................................................................................48

3.5.3 Emergency Response Plan................................................................................................48
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3.6 Product Tolling ..............................................................................................................................49

3.6.1 Client Responsibilities ......................................................................................................50

3.6.2 Toller Responsibilities ......................................................................................................51

3.7 City and County Emergency Management ....................................................................................53

3.7.1 Whitfield County Emergency Operations Plan.................................................................54

3.7.2 City and County Emergency Response.............................................................................56

4.0 REGULATORY ANALYSIS........................................................................................................60

4.1 OSHA.............................................................................................................................................60

4.1.1 Process Safety Management .............................................................................................60

4.1.2 Hazardous Waste Operations and Emergency Response..................................................61

4.2 EPA................................................................................................................................................62

4.2.1 Emergency Planning and Community Right to Know Act...............................................62

4.2.2 Risk Management Program...............................................................................................64

4.3 Georgia Regulations.......................................................................................................................66

4.3.1 Georgia Department of Natural Resources, Environmental Protection Division .............66

4.3.2 Georgia Emergency Response Commission.....................................................................67

4.3.3 Georgia Emergency Management Agency .......................................................................68

5.0 SIMILAR INCIDENTS.................................................................................................................69

5.1 Napp Technologies ........................................................................................................................69

5.2 Reactive Hazard Management .......................................................................................................70

5.3 Incidents Directly Involving TAC Manufacturing.........................................................................70

5.3.1 Early 1970s Overpressure and Fire Incident.....................................................................70

5.3.2 1979 Attempt to Manufacture TAC..................................................................................71

6.0 INDUSTRY ASSOCIATIONS .....................................................................................................72

6.1 Synthetic Organic Chemical Manufacturers Association ..............................................................72
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6.1.1 Responsible Care ..............................................................................................................72

6.1.2 Reactive Chemicals Hazards Awareness ..........................................................................72

6.2 AIChE/CCPS Tolling Guidance ....................................................................................................73

7.0 ROOT AND CONTRIBUTING CAUSES....................................................................................74

7.1 Root Causes ...................................................................................................................................74

7.2 Contributing Causes.......................................................................................................................75

8.0 RECOMMENDATIONS...............................................................................................................77

8.1 MFG Chemical, Inc. ......................................................................................................................77

8.2 GP Chemical ..................................................................................................................................78

8.3 Lyondell Chemical Company ........................................................................................................78

8.4 City of Dalton ................................................................................................................................79

8.5 Whitfield County ...........................................................................................................................79

8.6 Governor of the State of Georgia...................................................................................................80

8.7 Synthetic Organic Chemical Manufacturers Association ..............................................................81

9.0 REFERENCES ..............................................................................................................................82

APPENDIX A MFG TRIALLYL ALCOHOL PROCESS CHEMISTRY ANALYSES.........................85

APPENDIX B PLUME MODELING RESULTS .....................................................................................96

APPENDIX C LOGIC TREE..................................................................................................................108
 April 2006 

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Figures 

Figure 1. MFG Callahan Road facility layout .............................................................................. 10

Figure 2. Isotainer (tanker) used to ship 35,000 lbs of allyl alcohol ............................................ 12

Figure 3. Small batch test reactors ............................................................................................... 18

Figure 4. Portable cooling system used to cool the reactor, generator, and chiller unit............... 24

Figure 5. Basic TAC process diagram.......................................................................................... 25

Figure 6. The18-inch reactor manway.......................................................................................... 26

Figure 7. Isotainer positioned adjacent to the process equipment................................................ 26

Figure 8. Overpressure rupture disc and vent pipe on top of reactor ........................................... 28

Figure 9. Event Timeline.............................................................................................................. 32

Figure 10. Map showing MFG and nearby neighborhoods.......................................................... 33

Figure 11. Test cell reaction mass temperature and pressure as a function of time ..................... 41

Figure 12. Typical reaction heat production and cooling system heat removal vs. reactor 

temperature ................................................................................................................ 44
 April 2006 

vi 

Acronyms and Abbreviations 

ACC American Chemistry Council 

ATSDR Agency for Toxic Substances and Disease Registry 

AHC All Hazards Councils 

AIChE American Institute of Chemical Engineers 

BTU British thermal unit 

CAER Community Awareness and Emergency Response 

CCPS AIChE Center for Chemical Process Safety 

CFR Code of Federal Regulations 

CSB U.S. Chemical Safety and Hazard Investigation Board 

DOT U.S. Department of Transportation 

EH&S Environmental Health and Safety 

EMA Whitfield County Emergency Management Agency 

EMC Whitfield County Emergency Management Center 

EMS Hamilton Medical Center Emergency Medical Service (Paramedic and EMT 

ambulance service) 

EMT Emergency Medical Technician 

EPA U.S. Environmental Protection Agency 

EPCRA Emergency Planning and Community Right-to-Know Act 

EPD (Georgia) Environmental Protection Division of GDNR 

GC/MS Gas Chromatography and Mass Spectroscopy 

GDNR Georgia Department of Natural Resources 

GEMA Georgia Emergency Management Agency 

GERC/SERC Georgia (State) Emergency Response Commission 

GPC GP Chemical 
 April 2006 

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HAZWOPER Hazardous Waste Operations and Emergency Response 

IC Incident Commander 

IChemE Institute of Chemical Engineers 

IDLH Immediately dangerous to life or health 

LEPC Local Emergency Planning Committee 

MFG MFG Chemical, Inc. 

MSDS Material Safety Data Sheet 

NAICS North American Industrial Classification System 

NIOSH National Institute of Occupational Safety and Health 

NFPA National Fire Protection Association 

OSHA Occupational Safety and Health Administration 

PEL Permissible Exposure Limit 

ppm parts per million 

PSM Process Safety Management (29 CFR 1910.119) 

R&D Research and Development 

RMP Risk Management Plan (40 CFR 68, Subpart G) 

SARA Superfund Amendments and Reauthorization Act of 1986 

SCBA Self-Contained Breathing Apparatus 

SOCMA Synthetic Organic Chemical Manufacturers Association 

TAC Triallyl Cyanurate 
 April 2006 

1 

Executive Summary 

On the night of April 12, 2004, during an attempt to make the first production batch of triallyl 

cyanurate (TAC) at MFG Chemical, Inc. (MFG) in Dalton, Georgia, a runaway chemical reaction 

released highly toxic and flammable allyl alcohol and toxic allyl chloride into the nearby 

community. The fire department ordered an evacuation of residents and businesses within a halfmile of the facility. The release forced more than 200 families from their homes. One MFG 

employee sustained minor chemical burns and 154 people received decontamination and 

treatment at the local hospital for chemical exposure, including 15 police and ambulance 

personnel assisting with the evacuation. Five residents required overnight hospitalization for 

breathing difficulties. The reactor continued venting toxic vapor for nearly eight hours and the 

evacuation order lasted more than nine hours. 

The U.S. Chemical Safety and Hazard Investigation Board (CSB) determined that the runaway 

chemical reaction rapidly pressurized the reactor causing the manway seal to fail, and then 

activated the overpressure safety device. Unable to contain the toxic vapor or stop the runaway 

reaction, the release continued until the chemical reaction ceased. 

The CSB identified the following root causes of the incident: 

• MFG did not understand or anticipate the reactive chemistry hazards. They 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, which would have alerted them to the hazards 

involved in manufacturing TAC. 

• 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. 
 April 2006 

2 

• MFG did not prepare and implement an adequate emergency response plan. They 

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. The regulations 

require comprehensive engineering analyses of the process, emergency planning, a 

pre-startup safety review, and coordination with the local community before 

receiving the covered chemical at the site and introducing the covered chemical into 

the process. 

The CSB makes recommendations to MFG to develop and implement written procedures 

requiring comprehensive hazard review for all process changes and new processes, develop a 

comprehensive emergency response plan and train the employees, as well as two additional 

recommendations addressing toll manufacturing services and regulatory compliance review. 

Furthermore, the CSB makes recommendations to GP Chemical, Lyondell Chemical Company, 

the City of Dalton, Whitfield County, the Governor of the State of Georgia, and the Synthetic 

Organic Chemical Manufacturers Association. 
 April 2006 

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1.0 Introduction 

1.1 Background 

An attempt to manufacture a new product resulted in a runaway reaction1 that over-pressurized 

the reactor, activated the emergency vent, and released toxic vapor into the atmosphere, exposing 

and injuring facility employees, nearby residents, and emergency responders. The CSB 

concluded that this incident was avoidable. The company should have thoroughly investigated 

the hazards of the process and properly designed the emergency vent system to contain a potential 

release of the toxic vapor. Local emergency response agency all-hazard preparedness was not 

adequate for this event. The state emergency planning agencies could have assisted the local 

emergency response agencies in specific planning for hazardous chemical incidents. 

This report presents the findings and specific actions that the parties who were directly involved 

in the incident should take to prevent a recurrence. Small and large businesses who use 

hazardous chemicals, especially those involving reactive chemistry should closely examine the 

lessons learned from this incident, particularly those involving hazard reviews, process design, 

and emergency planning. Furthermore, emergency response agencies should closely examine the 

lessons learned, especially those that address businesses, residents, and other community 

stakeholders involvement with emergency planning. 

On the evening of April 12, 2004, MFG Chemical (MFG) was attempting to make the first 

production batch of triallyl cyanurate (TAC) at their Callahan Road facility in Dalton, Georgia. 

At approximately 9:30 PM, the reaction went out of control and over-pressurized a 4000-gallon 

 

1

 A runaway reaction is a reaction that is out of control because the heat generation rate from the reaction 

exceeds the rate at which the heat is removed from the system by the cooling media and the surroundings 

(CSB, 2002). 
 April 2006 

4 

reactor. The runaway reaction caused the release of highly toxic and flammable allyl alcohol 

vapor and toxic allyl chloride vapor into the community. The dense vapor continued to escape 

from the reactor for more than eight hours. Neither the Dalton Fire Department emergency 

responders nor MFG personnel had the personnel protective equipment required to enter the 

process area safely to attempt to stop the vapor release. The Dalton Fire Department promptly 

ordered an evacuation of all residents and businesses within a one-half mile radius of the facility. 

The Dalton Police Department then dispatched officers to the neighborhoods to alert the residents 

to evacuate. 

More than 154 individuals, including police, ambulance crews, and residents, were overcome by 

the toxic vapor and required treatment at the hospital for respiratory distress, and eye and skin 

irritation. One MFG employee sustained minor chemical burns to his skin and was treated and 

released. Five residents required overnight hospitalization. The fire department cancelled the 

evacuation order at 7:00 AM, more than nine hours after the incident started. 

The release exposed emergency responders, residents, and nearby businesses to toxic allyl alcohol 

and allyl chloride. Furthermore, the incident likely involved hazardous chemical reactions similar 

to incidents discussed in the U.S. Chemical Safety and Hazard Investigation Board (CSB) report, 

Improving Reactive Hazard Management" (CSB, 2002). Therefore, the CSB launched an 

investigation to determine the root and contributing causes and make recommendations to prevent 

similar occurrences. 

1.2 Investigative Process 

CSB investigators arrived on scene the morning of April 14, 2004. The investigation began with 

interviews with the MFG management and senior engineering personnel responsible for chemical 

process development, equipment, and the safety program at MFG. The CSB team then conducted 

a detailed examination of the process equipment, the chemical transport and storage tanker 
 April 2006 

5 

(isotainer), and the reactor cooling system. Investigators collected samples of the raw materials 

and residue from the reactor for analytical testing. 

The investigation included interviews with personnel from the Dalton Fire Department including 

the fire chief, battalion chief, safety coordinator, deputy fire chief, and the on-scene incident 

commander. Investigators interviewed the Dalton Police Department lieutenant responsible for 

the Patrol Division, the captain of the Support Services Division, and many of the police officers 

exposed to the toxic vapor cloud during the community evacuation. They also interviewed the 

Whitfield County Emergency Management Agency director, hospital personnel responsible for 

decontaminating and treating the individuals at the hospital, and ambulance services personnel 

including the dispatcher and the emergency medical technicians (EMT) and paramedics exposed 

to the toxic vapor the night of the incident. 

CSB investigators, assisted by individuals from the Whitfield County Health Department, 

Environmental Health Section conducted a door-to-door survey of 21 families evacuated from 

their residences, some of whom received decontamination and treatment at the hospital, and 

management personnel at local businesses in the evacuation area. Investigators interviewed the 

Georgia Department of Natural Resources on-scene investigator and management personnel in 

the Atlanta headquarters. CSB investigators also interviewed the president of GP Chemical, the 

company that contracted with MFG to manufacture the TAC, and personnel from Lyondell 

Chemical Company, the supplier of one of the raw materials used in the process. Officers from 

the Atlanta office of the Agency for Toxic Substances and Disease Registry (ATSDR) assisted 

the CSB by interviewing emergency room doctors and nurses at the Hamilton County Medical 

Center, the hospital where the people exposed to the toxic chemical underwent decontamination 

and treatment. 
 April 2006 

6 

The CSB convened a public meeting in Dalton, GA on November 16, 2004 to present the 

preliminary incident summary to the community. The Board solicited comments from the 

residents and emergency response agencies regarding their experiences during the emergency. 

The Whitfield County Emergency Management Agency Director presented a summary of the 

emergency response actions during the incident and a representative from the Hamilton Medical 

Center presented their observations on hospital staff performance during the emergency. 

The investigation team obtained the services of an engineering analysis and laboratory services 

consultancy to analyze the raw materials and recovered residue, and perform reactive chemistry 

testing of the chemical recipe2

 involved in the incident. The investigation team also contracted 

for modeling of the vapor cloud release. 

1.3 Key Findings: 

1. 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,3

 to the reactor at once, and were then unable to control the reaction 

rate. 

2. 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. 

 

2

 A recipe is a detailed instruction used to make a specific chemical. It typically includes equipment 

preparation prerequisites, raw chemical quantities, addition sequence, and critical process parameters 

such as timing, temperature, pressure, and flow. Recipes also usually contain warnings, cautions, and 

special personnel protective equipment need to manufacture the material. 

3

 A catalyst is a substance that promotes or increases the rate of a chemical reaction without changing its 

own composition. 
 April 2006 

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3. Lyondell Chemical (the allyl alcohol manufacturer) did not clearly communicate to MFG 

management or GPC (the allyl alcohol buyer) 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. 

4. 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. 

5. 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. 

6. MFG did not provide a hazardous vapor/liquid containment system on the reactor 

emergency vent. The runaway reaction released allyl alcohol and allyl chloride into the 

atmosphere and into a nearby creek. 

7. The Whitfield County Emergency Response Plan did not include a community shelter-inplace or an effective evacuation plan, nor did it provide prompt notification to the 

affected residents and businesses. 

8. 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. 

9. 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 
 April 2006 

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vapor cloud. The incident command also allowed inadequately protected MFG 

employees to reenter the toxic vapor cloud. 

10. 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. 

11. MFG employees conducted emergency response activities without the necessary 

procedures, training, or personnel protective equipment. One employee sustained 

chemical burns. 

12. The State of Georgia has not established clear responsibility for oversight of the 

regulatory requirements contained in the Emergency Planning and Community Right-toKnow Act (EPCRA), and did not identify deficiencies in the Whitfield County 

Emergency Operations Plan. 

1.4 Companies Involved 

1.4.1 MFG Chemical, Inc. 

MFG began operations in 1979. It employs approximately 35 personnel at two chemical 

manufacturing facilities, one located on Brooks Road and the other located on Callahan Road in 

Dalton, GA. Manufactured chemical products include emulsified mineral oils, phosphate esters, 

surfactants and sulfosuccinates (wetting agents), and various polymers. MFG produces many of 

these products in tolling arrangements4

 with other companies. The MFG analytical laboratory 

 

4

 “Tolling” is a contractual agreement between two companies to produce material products. The toller, 

client, or both may provide the raw materials to the toller. The client usually retains ownership and 

controls the sale of the product. The toller usually provides the facility, equipment, labor, and other 

resources to manufacture the product. 
 April 2006 

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performs product quality verification, and research and development for new or modified 

products. The Callahan Road facility (Figure 1) was selected to manufacture the TAC because it 

had a 4000-gallon, glass lined reactor (R4) and associated equipment needed for the chemical 

synthesis. It is approximately five miles southwest of the Brooks Road facility. The staff includes 

the president, plant manager, three Ph.D. organic chemists, and a chemical engineer. The 

chemical engineer is responsible for the safety and health program. 

MFG is a member of the Synthetic Organic Chemical Manufacturers Association (SOCMA) and 

actively participates in trade shows and other industry activities. 

1.4.2 GP Chemical 

MFG agreed to produce TAC in a tolling agreement with GP Chemical (GPC). GPC started 

business in 1990 to develop new chemical processes, and market and sell chemical products. It 

employs three full-time individuals in the New Jersey office. One is a chemist with more than 15 

years of experience with producing specialty chemicals. GPC is a 50% owner of a chemical 

manufacturing facility in Tennessee. The Tennessee facility also serves as a pilot plant for 

developing new chemical products. 
 April 2006 

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Figure 1. MFG Callahan Road facility layout. 

GPC began discussions with MFG in late 2002 to procure tolling services for TAC, a chemical 

used in the manufacturing of rubber and other polymers. The two companies began discussing 

the details of the manufacturing process, which included selecting raw material suppliers, 

handling production quantities, and delivery schedules. GPC (the client) issued a purchase order 

to MFG (the toller) in January 2004 for the manufacture of the first production quantity of TAC. 
 April 2006 

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1.4.3 Lyondell Chemical Company 

GPC contracted with Lyondell Chemical Company (Lyondell) to provide the allyl alcohol to 

MFG. Headquartered in Houston Texas, Lyondell is a worldwide producer of basic chemicals 

and derivatives and is the sole manufacturer of allyl alcohol in the United States. 

Lyondell maintains a product stewardship program5

 for all hazardous chemicals that they 

manufacture. Three months before delivering the allyl alcohol, Lyondell personnel visited the 

MFG facility and conducted an assessment to evaluate the preparedness of MFG to handle a large 

quantity of allyl alcohol safely. Lyondell concluded that MFG could safely handle production 

quantities of allyl alcohol after they made improvements in fire suppression equipment, and 

provided additional personal protective equipment and training to employees who would be 

working with the chemical. On April 4, 2004, GPC issued a purchase order to Lyondell to supply 

35,000 pounds (4940 gallons) of allyl alcohol to MFG. An isotainer of allyl alcohol arrived on 

April 12, 2004, a few hours before the incident occurred, and was parked adjacent to the reactor 

(Figure 2). 

 

5

 Product stewardship is a product-centered approach to environmental protection. It calls on those in the 

product lifecycle—manufacturers, retailers, users, and disposers—to share responsibility for reducing the 

environmental impacts of products. Source: EPA website, June 2005. 
 April 2006 

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Figure 2. Isotainer (tanker) used to ship 35,000 lbs of allyl alcohol (looking east). 

1.5 Chemical Characteristics 

1.5.1 Allyl Alcohol 

The National Fire Protection Association (NFPA) classifies allyl alcohol as a Class IB, extremely 

flammable liquid. The flashpoint6

 is 70° F and the flammable limits7 range from 2.5% to 18% by 

volume. Allyl alcohol is toxic and poses a severe inhalation hazard, high skin absorption hazard, 

and high ingestion hazard. It is corrosive to the eyes and is a severe skin irritant. The 

Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) is 2.0 

 

6

 Flashpoint is the minimum temperature at which a liquid will give off sufficient vapors to form an 

ignitable mixture with air near the surface, but will not sustain combustion. 

7

 Flammable limit is the lower or upper concentration of vapor in air at which propagation of flame will 

occur in the presence of an ignition source. 
 April 2006 

13 

parts per million (ppm) based on an eight-hour time weighted average. The National Institute of 

Occupational Safety and Health (NIOSH) lists 20 ppm as Immediately Dangerous to Life or 

Health (IDLH). Smell does not provide adequate warning of potentially hazardous air 

concentrations because odor thresholds are imprecise and the allyl alcohol PEL is within the odor 

threshold range of 1.4 ppm and 2.1 ppm (AIHA, 1989).

OSHA and EPA both regulate allyl alcohol. When used in quantities of 10,000 pounds or greater, 

allyl alcohol is an OSHA Process Safety Management (PSM) regulated flammable liquid (Section 

4.1.1). It is an EPA Risk Management Program regulated toxic chemical when used in quantities 

of 15,000 pounds or greater (See Section 4.2.2).8

1.5.2 Cyanuric chloride 

Cyanuric chloride is a fine white, crystalline powder with a pungent odor that strongly irritates 

the skin, mucous membranes, respiratory, and gastrointestinal tracts. It is highly reactive. 

Cyanuric chloride has no specified occupational exposure limits, nor is it covered in the PSM or 

Risk Management Program regulations. 

1.5.3 Allyl Chloride 

Allyl chloride is a colorless highly flammable and toxic liquid. It is extremely irritating to the 

respiratory system, eyes, and skin. The odor threshold ranges from one to five parts per million. 

The vapor is heavier than air. 

 

8

 To protect the workers in the facility, the OSHA PSM standard regulates flammable liquids as a group 

based on the flammable characteristics of the liquid, and 137 specifically named toxic chemicals. To 

protect the environment and the public, the EPA Risk Management Program regulates 63 specifically 

named flammable gasses and volatile liquids, and 77 specifically named toxic chemicals. 
 April 2006 

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1.6 Triallyl Cyanurate Process Development 

1.6.1 GP Chemical Studies 

A company interested in a multi-year contract to purchase large quantities of TAC from a U.S.-

based manufacturer contacted GPC. GPC identified an expired American Cyanamid patent that 

provided a straightforward method to manufacture TAC and produced one laboratory-scale test 

batch in a three-liter flask to confirm that the basic recipe would produce a product that met the 

quality standards established by their customer. 

GPC identified two important manufacturing considerations: 1) the chemical reaction liberated 

significant heat. Controlling the heat would require an adequate cooling system as well as slow, 

controlled addition of the chemicals, and 2) the fine powder form of one of the chemicals in the 

recipe required careful addition to control the reaction rate. GPC discussed these issues with 

MFG management and concluded that they understood the issues. 

GPC began negotiations with MFG in late 2002 to manufacture TAC at their Dalton, GA facility. 

They signed a confidentiality agreement, the only formal contractual document executed for the 

tolling activity. It included a provision for MFG to hold confidential from GPC certain 

refinements or improvement in the catalyst used in the process. The agreement also provided for 

GPC to review the final chemical recipe prior to the first production batch. They did not arrange 

for GPC to observe or participate in the first TAC production batch. 

GPC and MFG met in August 2003 where they discussed methods for controlling the rate of 

addition of the dry powder chemical into the reactor. They discussed the reactor cooling system 

performance requirements at a meeting the following December. The companies verbally agreed 

on other key elements, including financial arrangements for the temporary reactor cooling system 

and the purchase of the raw materials. GPC issued a purchase order to MFG in January 2004 to 
 April 2006 

15 

produce the first 20 tons of TAC, with the expectation of subsequent purchase orders after the 

acceptance of the first batch by their customer. They indicated that their customer was anxious 

for the delivery of large quantities of TAC. 

1.6.2 MFG Studies 

MFG personnel conducted a literature search to confirm that there were no patent restrictions that 

could adversely affect their TAC production. However, they did not conduct detailed literature 

research addressing the reactive chemistry hazards involved in the process (Section 5.3). 

1.6.2.1 TAC Synthesis 

MFG intended to synthesize triallyl cyanurate by reacting cyanuric chloride with allyl alcohol in 

the presence of a catalyst. 

Allyl Alcohol + Cyanuric Chloride + Catalyst → TAC + Hydrogen Chloride + Catalyst 

The reaction produces hydrogen chloride (HCl) as a by-product. In order to ensure complete 

conversion of the cyanuric chloride, the procedure specified an excess amount of allyl alcohol.9

 

MFG planned to synthesize fixed-volume batches of TAC using a 4000-gallon reactor equipped 

with an external cooling-jacket (See Figure 2). 

The procedure specified a slow addition of a caustic soda solution to the batch after thoroughly 

mixing the reactants. The caustic soda would neutralize the HCl produced in the synthesis 

reaction. MFG personnel understood that the neutralization reaction was very exothermic (i.e., 

heat generating), so they planned to circulate coolant through the reactor jacket to prevent the 

mixture from overheating. MFG did not anticipate that the reaction between the allyl alcohol and 

 

9

 "Excess" as used in the chemistry context, is a means of driving a reaction to a desired endpoint. It does 

not imply that the amount of allyl alcohol was excessive in a safety context. 
 April 2006 

16 

the cyanuric chloride was also highly exothermic and could generate significant heat (Section 

1.8.2). The MFG laboratory test results indicated the heat generated during the neutralization 

step would require the highest rate of reactor cooling. 

After the synthesis and neutralization were complete, the addition of an inhibitor to the batch 

would prevent polymerization of the TAC. Next, heating the batch would distill off the excess 

allyl alcohol. Finally, MFG would ship the washed, dried, and packaged TAC. 

1.6.2.2 Batch Recipe Refinement 

In the first half of 2003, MFG conducted laboratory scale testing of TAC recipes, but only for 

improving the yield and minimizing production cost. MFG and GPC discussed various 

techniques to control the maximum temperature from the exothermic reaction, including 

rearranging the sequence of chemical addition into the reactor and providing an adequately sized 

a reactor cooling system. However, despite the laboratory experiments, patent research, and 

discussions between the two companies, they never learned of the significant potential for an 

exothermic decomposition reaction. 

MFG performed three batch tests in the 30-gallon reactor (Figure 3), but the final production 

batch procedure was different from the test batch procedures. The first two batches did not use a 

catalyst. They both used an incremental chemical addition sequence that included neutralizing 

the mixture with caustic soda at each increment. They added cyanuric chloride then caustic soda 

in small increments while maintaining the batch temperature below 95 °F. The third test batch 

loaded the entire quantity of allyl alcohol, cyanuric chloride, and the catalyst, then controlled the 

batch temperature below 50 °F, which was easy to accomplish in the 30-gallon reactor. The 

second and third test batches used recycled allyl alcohol from the first test batch, not fresh allyl 

alcohol. 
 April 2006 

17 

The procedure used to attempt the full-scale TAC production in the 4000-gallon reactor was 

similar to the third 30-gallon reactor test, but used only fresh allyl alcohol and did not limit the 

batch temperature. The production procedure did not specify the incremental addition and 

neutralization steps used in the first two test batches. The production batch procedure contained 

no chemical addition rate restrictions, critical for controlling the reaction rate even though 

management had discussed the issue with GPC. 

Controlling the temperature of the reacting chemicals was significantly more difficult in the 

4000-gallon reactor than in the 30-gallon reactor. The heat removal capacity of a reactor 

equipped with an external jacket is directly proportional to the ratio of the jacketed surface area to 

the reactor volume. This surface-to-volume ratio decreases as the reactor volume increases,10

thus the ability to remove excess heat may be significantly less in a large production reactor 

compared to the bench-scale reactor. Scaling to the 4000-gallon production reactor made 

controlling the batch temperature much more difficult. 

 

10 This assumes that both the small and large reactor have a similar height-to-diameter ratio, percent of 

jacketed surface area on the reactors, and agitator mixing characteristics. 
 April 2006 

18 

Figure 3. Small batch test reactors. Reactor cooling jacket (arrow) is similar to the 4000-gallon 

production reactor. 

1.7 Pre-Startup Hazard Planning 

1.7.1 Lyondell Allyl Alcohol Product Stewardship 

Recognizing the toxic and flammable hazards associated with allyl alcohol, Lyondell published 

the Allyl Alcohol Product Safety Bulletin (Lyondell, 2004), a 74-page guide for handling, 

transporting, and using allyl alcohol. The bulletin discusses physical and chemical hazards; 

exposure limits, detection, and first aid; engineering safeguards and fire safety; hazard 

communication; and storage and transportation. It only briefly summarizes the OSHA and EPA 

regulations specifically applicable to allyl alcohol. It only lists PSM in Product Storage, Section 

8 and References, Appendix V. The EPA Risk Management Program regulation is in the 

Regulatory Summary, Appendix VI but the appendix does not list PSM. A discussion of these 

regulations is in Section 4.0 of this report. 

Lyondell conducted a site review at the MFG facility in January 2004, four months before 

delivering the allyl alcohol. A representative from the Lyondell, Houston logistics department, 
 April 2006 

19 

the technical services manager at the allyl alcohol manufacturing plant, and the allyl alcohol unit 

process specialist, met with the MFG personnel for about three hours to review the site safety 

program and evaluate the capabilities of MFG for handling large quantities of allyl alcohol. They 

also provided a copy of the product safety bulletin to MFG. 

The team leader used a checklist, developed by the Lyondell European business unit, to guide the 

assessment. However, it lacked U.S.-specific elements such as the OSHA PSM and EPA Risk 

Management Program regulations. Furthermore, the checklist only addressed Lyondell’s 

concerns about the safe handling of allyl alcohol; it did not address any process design and 

emergency containment considerations, or production issues involving the use of the allyl 

alcohol. 

Lyondell and MFG did not discuss the PSM standard or the Risk Management Program 

regulations during the site visit, or at any other time prior to the April 2004 incident. Only one of 

the assessment team members was even aware of the PSM program requirements. All three 

stated in interviews that they were not aware that the Risk Management Program regulation 

applied to allyl alcohol. 

The assessment team concluded that Lyondell would permit MFG to receive and handle the allyl 

alcohol upon completion of two important actions: 

• Require MFG employees who would connect the isotainer to the process equipment and 

transfer the allyl alcohol to wear positive pressure air purifying respirators or full face 

respirators equipped with organic cartridges to protect them from toxic vapor exposure, 

• Notify the Dalton City Fire Department of the intent to use allyl alcohol and confirm that 

the fire department had foam fire suppression capabilities. 
 April 2006 

20 

Although MFG implemented the prerequisites, the safety program provisions only addressed 

small allyl alcohol releases. MFG management informed Lyondell that they would rely on the 

Dalton City Fire Department to handle any large allyl alcohol release. Lyondell then approved 

the allyl alcohol delivery to MFG. 

1.7.2 MFG Safety Program 

MFG routinely used flammable and toxic chemicals in their manufacturing facilities and 

employed a full-time engineering and compliance manager to oversee the worker safety and 

environmental compliance programs. They conducted training with the affected employees 

whenever they planned to handle new chemicals. The training addressed the contents of each 

material safety data sheet (MSDS) and any special precautions. 

As a member of the Synthetic Organic Chemical Manufacturers Association (SOCMA), MFG 

used the Responsible Care program self-evaluations to review their safety programs. They 

conducted self-assessments for the Process Safety program, the Environmental Health & Safety 

(EH&S) program, the Product Stewardship program, and the Community Awareness and 

Emergency Response (CAER) program. Each self-assessment concluded their programs were 

adequate. 

Management was aware of the PSM standard but reported that they never handled any of the 

listed toxic chemicals or covered flammable liquids in quantities above the regulatory threshold 

limits prior to receiving the allyl alcohol. Management also reported that they had never applied 

the EPA Risk Management Program regulation to any chemicals at the facility. 

MFG did not implement a PSM program for the TAC process (Section 4.1.1). They concluded 

that maintaining the quantity of allyl alcohol used in the TAC batch below the 10,000-pound 
 April 2006 

21 

flammable liquid threshold quantity was sufficient to avoid implementing a PSM program.11 

Furthermore, they concluded that although the isotainer was connected to the process, the allyl 

alcohol in the isotainer12 met the flammable exemption provided in §1910.119 (a)(ii)(B).13 

1.7.2.1 On-site Safety Upgrades 

MFG prepared a written procedure for the operations personnel to use when transferring the allyl 

alcohol into the process equipment. The procedure required each employee assigned to 

transferring the allyl alcohol from the isotainer to the reactor to wear full-face respirators with 

organic cartridges and acid-resistant clothing, gloves, and boots. The procedure did not contain 

any requirement for the employees to measure the allyl alcohol vapor concentration in the air; 

critical data needed to determine if the personal protective equipment (PPE) they were using 

would provide adequate protection in the event of a significant spill. Furthermore, management 

had not purchased air-monitoring devices suitable for detecting allyl alcohol nor did they 

purchase "Level A" personal protective equipment14 if the vapor concentration level necessitated 

its use. 

MFG purchased a 125-pound portable foam fire extinguisher and provided training to the 

employees who would be conducting the TAC production activities. They also contacted the 

 

11 OSHA has provided in the Preamble to the final PSM rule and in interpretation letters that reducing the 

quantity of a covered chemical or flammable liquid to a quantity less than the threshold quantity is an 

acceptable technique for excluding the process from PSM compliance. 

12 In a 1994 PSM interpretation letter, OSHA advised that a commercial tank motor vehicle is subject to 

OSHA standards, rather than the DOT regulations once the commercial tank motor vehicle is no longer 

"considered 'in transit' by DOT." (OSHA, 1994). DOT provided additional clarification to the 

applicability of the Hazardous Material Regulations (49 CFR Subchapter C) such as cargo tanker 

unloading in the Final Rule promulgated in October 2003 (DOT, 2003). 

13 The flammable liquid exemption applies to a qualified atmospheric tank containing a qualified 

flammable liquid regardless if it remains connected to the process (OSHRC Docket No. 95-0341, 

Secretary of Labor vs. Meer). 

14 Level A protection includes totally encapsulating chemical protective clothing and self-contained 

breathing apparatus as required by 29 CFR 1910.120. 
 April 2006 

22 

Dalton City Fire Department and confirmed that the nearest fire station (Station 2) had foam fire 

suppression equipment useable in the event of a spill or fire involving allyl alcohol. 

1.7.2.2 MFG – Dalton Fire Department Planning 

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 at the facility. MFG management told CSB 

investigators that they assumed that the fire department would provide all emergency response 

tasks in the event of a significant release. Their procedure and training only covered very small 

releases. However, the fire department told investigators that their discussions with MFG 

management clearly explained that the fire department was not qualified or equipped to respond 

to a toxic chemical release15 and that the company would have to make provisions for such an 

event. 

MFG management provided a copy of the Lyondell allyl alcohol product safety bulletin to the fire 

department and verbally informed them of their intent to handle allyl alcohol. They also agreed 

to notify them after the allyl alcohol isotainer arrived on site, but before connecting it to the 

reactor. The fire department agreed that they would send a representative to the facility, only to 

become familiar with the placement of the isotainer and discuss emergency response activities 

with operators and supervisors before they started the production run. However, MFG did not 

notify the fire department when the allyl alcohol arrived, so the fire department site visit did not 

occur. 

 

15 Although the Dalton City Fire Department at one time maintained a HAZMAT response team, the fire 

department disbanded it due to city funding limitations. 
 April 2006 

23 

1.8 Process Controls and Cooling System 

1.8.1 Process Instruments 

The operator console was located approximately 20 feet south of the reactor on the mezzanine 

floor inside the building. It was equipped to monitor only two process parameters; the weight of 

the chemicals measured by the load cells,16 and the temperature inside the reactor. The reactor 

pressure was only available at a pressure gauge mounted on the reactor. It was not possible to 

read the pressure gauge from the console or the building door (See Figure 1). The agitator speed 

controller was also located at the console. 

1.8.2 Reactor Cooling System 

Early discussions between GPC and MFG included the possibility that the primary (TAC 

synthesis) reaction could generate significant heat. However, when MFG prepared the detailed 

procedure, they did not perform the necessary cooling system analysis for the primary reaction. 

The process engineer performed only a calculation to estimate the total heat load on the reactor 

during the hydrogen chloride neutralization step. The engineer then gave the chiller specification 

to GPC who contacted an equipment rental company to provide the portable chiller system. GPC 

did not confirm the cooling system design basis used by MFG and assumed that they had properly 

considered the heat load of the primary reaction. 

The chiller system arrived late in the morning of Monday, April 12, 2004 (Figure 4). The vendor 

technician made the necessary piping connections to the reactor cooling-jacket, started the 

system, and verified that it was operating properly. He then instructed the MFG personnel how to 

 

16 Load cells are electronic weight scales placed beneath the reactor support legs. The weight of the 

chemicals is equal to the total weight minus the weight of the empty reactor and attached equipment. 
 April 2006 

24 

start and stop the system. Since the TAC procedure did not specify any cooling system 

adjustments, the chiller system was not set up to provide for easy adjustments. 

Figure 4. Portable cooling system used to cool the reactor. Generator (left), and chiller (right). 

1.9 Chemical Addition Sequence 

1.9.1 Dry Chemical Loading 

The operators loaded the dry-powder cyanuric chloride into the reactor on Friday, April 9, 2004 

three days before the allyl alcohol and the temporary reactor cooling system arrived. They wore 

the personal protective equipment recommended on the MSDS. The reactor load cells on the 

reactor (Figure 5) measured the weight of the chemical specified in the procedure. The operators 

closed the reactor manway and installed some of the hold-down clamp bolts (Figure 6), after 

which a nitrogen gas blanket was established. The dry-powder chemical remained in the reactor 

throughout the weekend. 
 April 2006 

25 

Figure 5. Basic TAC process diagram. 

1.9.2 Allyl Alcohol Delivery and Connection to the Process 

The allyl alcohol isotainer arrived in the afternoon on Monday, April 12 and was parked adjacent 

to the reactor (Figure 7). The engineering and compliance manager met with the operators and 

discussed the precautions and personnel protective equipment required for the allyl alcohol 

transfer into the reactor. They then connected the transfer hose to the process piping. The 

operators concluded the chiller was providing sufficient cooling to the reactor because the reactor 

interior temperature reading was 32° F and the reactor cooling-jacket and chiller piping were frost 

covered. They were finally ready to proceed with the remaining steps in the procedure. 
 April 2006 

26 

Figure 6. The18-inch reactor manway. 

Figure 7. Isotainer (right) positioned adjacent to the process equipment. 
 April 2006 

27 

1.9.3 Final Chemical Addition 

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. 

After a few minutes of transferring allyl alcohol into the reactor through the transfer piping, they 

concluded that it was going to require many hours to complete the transfer at the established flow 

rate. Because the procedure did not restrict the allyl alcohol fill-rate, the operators increased the 

nitrogen pressure to speed the transfer. At the higher flow rate, they completed the transfer in 

less than an hour. The operators closed both transfer-hose isolation valves, but left the hose 

attached to the equipment. The reactor agitator had been started sometime during the transfer 

operation to mix the chemicals (See Figure 5). 
 April 2006 

28 

2.0 Incident Description 

2.1 Process Upset 

A short time after loading the allyl alcohol, the operators noticed that the reactor temperature had 

increased from 32° F to about 72° F, presumably due to the addition of the warm allyl alcohol. 

Ten minutes later, the operators noted that the temperature had already climbed to 103° F. The 

temperature continued to increase rapidly to 118° F, well above the peak temperature of about 

100° F that they expected. Unknown to the engineers and operators, it was almost at the 

temperature at which the exothermic decomposition reaction occurs (Section 3.1.2). Rapidly 

increasing pressure in the reactor caused the manway gasket to blow out (See Figure 6). Dense, 

white vapor immediately began to spray out of the manway. The rupture disc (Figure 8) blew 

open about 30 seconds later, sending additional white vapor out of the end of the 4-inch vent pipe 

near the base of the reactor. The last observed reactor temperature was 124°F. 

Figure 8. Overpressure rupture disc and vent pipe on top of reactor. An exemplar of the rupture 

disc (right). 
 April 2006 

29 

2.2 Facility Evacuation 

Operators initially considered approaching the reactor manway to attempt to reseal the gasket, but 

the leak was too large to stop and the venting vapor was moving toward them. With the two 

reactants and the catalyst fully charged into the reactor, no ability to increase the cooling rate, no 

emergency dilution system, and no reactor vent scrubber,17 they had no choice but to evacuate the 

area. All seven personnel safely evacuated the facility as the vapor cloud rapidly expanded and 

began drifting off site to the north and east. 

A 9:34 PM call informed the Whitfield County 911 Emergency Management Center that a 

"chemical release involving allyl alcohol" was occurring at the MFG Callahan Road facility. The 

emergency operator notified the Dalton City Fire Department dispatcher that there had been a 

"chemical spill" and the fire department should respond. 

2.3 Emergency Response 

The event timeline is shown in Figure 9. The following is a discussion of the significant events 

during the emergency response and community impact from the toxic vapor release. 

2.3.1 First Responder Actions 

The Whitfield County Emergency Management Center (EMC) dispatcher informed the fire crew 

that they were to respond to a “hazmat spill inside the building" at the facility. The dispatcher 

advised them that the material spilled was “alloy" alcohol. Responding firefighters unknowingly 

 

17 A reactor vent scrubber, neutralizes toxic material released from the reactor vent. The reactor vented 

directly to the ground under the reactor. 
 April 2006 

30 

drove through the dense vapor cloud that was drifting over Lakeland Road, east of the facility 

(Figure 10).18 The acrid odor immediately irritated their eyes and nostrils. 

Concluding that the incident was much more serious than merely a “spill”, they directed the other 

responding unit to take an alternate route to the facility and requested the dispatcher to call a chief 

officer to the incident scene. They also requested the dispatcher to alert the police department to 

dispatch police in preparation for a possible evacuation of the residents. Fire crews also 

requested that the police close Lakeland Road, north and south of the facility. About ten minutes 

had elapsed from the start of the vapor release. 

Placing the community's wellbeing above their own safety, emergency responders entered the 

already-contaminated neighborhoods to alert the residents to evacuate the area. None of the 

responding police officers had the training or safety equipment needed to enter the neighborhoods 

but there was no other available notification method. The first police officer in the area 

immediately reported that there was a "real thick chemical odor” in the area. The police sergeant 

in command directed four police units to evacuate nearby apartments while directing other units 

to evacuate a nearby subdivision. The sergeant instructed one patrol officer to go door-to-door to 

alert residents because his vehicle PA system was not working. Another patrol officer requested 

the dispatcher to ask the fire department if there was need for any type of protective equipment, 

but he never received a reply. All of the responding officers were reporting significant noxious 

odors. 

An ambulance crew, responding to a 911 call from a resident, informed the dispatcher that a 

strong chemical odor was noticeable as soon as they entered the neighborhood. Overcome by the 

 

18 The fire crew told CSB investigators that they saw what appeared to be low-lying fog caused by the cool, 

rainy weather drifting across the street as they approached the facility. 
 April 2006 

31 

vapor while walking from the ambulance to the residents' home, the EMT and paramedic 

retreated from the neighborhood. 

The crew soon pulled off the road and radioed the dispatcher to request assistance. The toxic 

vapor affected both the EMT and the paramedic, but only the EMT experienced a severe reaction 

that required long-term treatment. A second ambulance crew arrived and transported the stricken 

EMT and four residents who had stopped and requested medical aid to the hospital. 

2.3.2 Initial On-Site Response Activities 

MFG personnel informed the fire department Incident Commander (IC) that the reactor had 

overheated and they expressed concern that it needed cooling. They advised the IC to spray 

water on the releasing vapor cloud and reactor and recommended the evacuation of the 

community downwind. 

The first responding fire department lieutenant addressed the immediate concerns of the 

emergency responders and community. He notified the dispatcher that "a precautionary 

evacuation of nearby residents might be needed" and reported the hazard placard identification 

number on the side of the isotainer to the dispatcher, confirming that allyl alcohol was the likely 

chemical involved.19 He then established an incident command post outside the fence, at the 

southwest corner of the facility. The dispatcher then informed the IC that the DOT Emergency 

Response Guidebook (Guide 131)20 advises an evacuation distance of 4/10ths of a mile for a large, 

nighttime allyl alcohol spill. The IC directed the police to alert and evacuate the residents and 

businesses within a half mile downwind, north and east of the facility. 

 

19 The allyl alcohol hazard placard identification number is 1098. 

20 The Emergency Response Guidebook provides first responders with specific or generic hazards of the 

materials involved, and methods to protect themselves and the general public during the initial response 

to a release. 
 April 2006 

32 

Figure 9. Event Timeline (Scale: 60 minutes / division). 
 April 2006 

33 

Figure 10. Map showing MFG and nearby neighborhoods. Wind out of the south. 
 April 2006 

34 

One of the MFG chemists called the Lyondell Emergency Response Manager in Houston, TX 

shortly after the fire department arrived on scene. The IC consulted with the Lyondell manager 

throughout the incident response. Lyondell recommended that the fire department spray foam on 

the liquid pool beneath the reactor to help suppress the vapor cloud. Lyondell also suggested that 

MFG attempt to place a container of water under the rupture-disc vent pipe since it vented 

directly to the atmosphere rather than safely venting into a hazardous material containment 

device, such as a scrubber. They hoped that by discharging the vapor directly into the water, any 

allyl alcohol in the vapor would dissolve in the water (Section 2.3.6). 

2.3.3 Community Evacuation 

Thirteen minutes after the MFG call to 911 (9:47 PM Monday night) the police department began 

evacuating residents. Having no emergency sirens or other community-wide emergency alert 

system, the police officers proceeded into the vapor-contaminated neighborhoods and used their 

PA system or went door-to-door as necessary, to instruct the residents to evacuate their homes. 

All responding police officers reported to the dispatcher that they experienced severe eye, nose, 

and throat discomfort as they approached the communities near the MFG facility. 

The police sergeant requested the fire department to provide personnel with self-containedbreathing-apparatus (SCBA) to take over the evacuation. The unprotected police officers reported 

extreme difficulty breathing. Twenty minutes into the evacuation, and after notification of the 

continuing police officers distress, the fire department lieutenant directed the police officers to 

leave the area and the SCBA-equipped fire crews took over. Five police officers required 

transport to the hospital for decontamination and treatment for exposure to allyl alcohol vapor. 

At 11:15 PM, the IC directed the fire crews to make one more pass through the neighborhoods 

using their PA system to announce the evacuation. Three hours later, the IC extended the 
 April 2006 

35 

evacuation to the businesses and residents south and west of the MFG facility because of 

changing wind direction. The IC finally cancelled the evacuation order just before 7:00 AM. 

2.3.4 Triage of Injured Individuals 

The fire department established a triage station at Fire Station 2, three miles north of the MFG 

facility. There, paramedics and emergency medical technicians (EMT) from the Hamilton 

Medical Center evaluated the injured. Police and fire crews directed individuals having 

significant difficulty breathing or complaining of burning sensations in their eyes, nose, and 

throat to the triage station. 

Over the next two hours, an EMS ambulance crew made seven trips to the hospital, three miles 

north of the triage station. They transported 35 patients, including two EMS employees and the 

five injured police officers. 

2.3.5 Toxic Chemical Decontamination and Treatment 

The EMC dispatcher alerted the Hamilton Medical Center emergency room to prepare for people 

exposed to allyl alcohol. Emergency room personnel investigated the potential health impacts as 

well as the appropriate decontamination and treatment, and prepared a fact sheet for use by their 

personnel. The on-call emergency room physician consulted with the Georgia Poison Control 

Center, and reviewed the allyl alcohol MSDS. The Hamilton Medical Center declared a “Code 

Yellow” event at 10:29 PM, activating the Mass Casualty Plan.21 

Emergency room personnel set up a decontamination station outside the hospital. 

Decontamination consisted of disrobing then rinsing the entire body with a cool water spray. 

 

21 The hospital declares a Code Yellow event if more than ten casualties are expected to be received and 

treated and calls off-duty doctors, nurses, and other personnel, to assist with treating the casualties. 
 April 2006 

36 

Although hospital personnel did not collect and handle the potentially contaminated water, there 

was no reported environmental damage at the hospital. Hospital personnel placed personal 

belongings in sealed plastic bags and returned them to the owners with instructions for cleaning 

to remove residual allyl alcohol. 

Only one patient, an MFG employee, required treatment for minor chemical burns from the toxic 

vapor. Five of the 154 individuals treated at the hospital required overnight treatment that 

included oxygen and albuterol.22 The hospital treated thirteen police officers and four ambulance 

personnel for toxic chemical exposure. 

2.3.6 Mitigation and Containment of the Toxic Vapor Cloud 

The fire department operated in an "awareness level" response mode, performing defensive 

measures while remaining safely upwind of the toxic vapor because they did not have appropriate 

toxic chemical monitoring devices, protective clothing, or a trained and equipped hazmat 

response team. They used a four-gas detector device to monitor the air for the following 

chemicals: hydrogen sulfide, carbon monoxide, flammable vapor, and oxygen. Firefighters set 

up unmanned water cannons and directed the water flow on the top of, and around the reactor to 

in an attempt to absorb the releasing vapor23 and to cool the reactor. The fire department decided 

not to use any vapor containment foam because the significant water volume spraying on the 

reactor would disrupt a foam cover and render it ineffective. Cooling the reactor was their first 

priority. 

 

22 Albuterol is an inhaled preparation used in the relief and prevention of airway constriction caused by 

asthma and other conditions with reversible airway obstruction. 

23 Allyl alcohol is highly soluble in water so a water fog spray is an effective method to contain the vapor. 
 April 2006 

37 

With the concurrence of the deputy fire chief, the IC permitted three MFG personnel to reenter 

the building to check the reactor temperature, quickly observe the reactor equipment, check on 

the status of the reactor cooling system, and retrieve their respirators from the building. The IC 

made it clear to the MFG personnel that they would enter at their own risk. Furthermore, the fire 

department would not attempt a rescue in the event that an employee was overcome by the vapor, 

or sustained serious injury during the entry since the fire department personnel did not have the 

protective equipment required for allyl alcohol exposure. Nevertheless, the inadequately 

protected MFG employees entered the facility without monitoring the allyl alcohol vapor 

concentration in the air. After the first entry into the building, one MFG employee returned to the 

building to retrieve the MSDS for the fire department. 

Two Dalton Utilities employees arrived at 11:18 PM and informed the IC that firewater runoff 

was entering the storm-water drainage canal that flowed into the nearby Stacey Branch creek (See 

Figure 10). The IC decided that it was more important to minimize the airborne concentration of 

the chemical so they continued applying water to the reactor to knock down the vapor, 

acknowledging that contaminated water would enter the creek. The Georgia Department of 

Natural Resources subsequently conducted a survey of the creeks after the incident and 

determined that a significant aquatic kill occurred as far as seven miles downstream from the 

facility. 

Shortly after 2:00 AM, the IC again permitted MFG personnel wearing only Tyvek/Tychem®

suits, boots, gloves and full-face cartridge respirators,24 to return to the process equipment to 

place a 5-gallon bucket filled with water under the rupture disc vent-pipe. The Lyondell 

Emergency Response Manager recommended this makeshift vapor scrubber to reduce the 

 

24 The Emergency Response Guidebook specifies fully encapsulating, vapor protective clothing when 

entering an allyl alcohol spill area. (U.S. DOT, 2004) 
 April 2006 

38 

quantity of toxic vapor being released. However, the bucket had no effect on the continuing 

vapor release through the manway. The fire department did not monitor the air for toxic vapor 

concentration in the area during this activity. 

At 5:30 AM, more than seven hours after the release had started, the fire department concluded 

based on visual observations and the four-gas detector device readings that the vapor release had 

subsided sufficiently to permit them to stop the water spray. MFG personnel reentered the 

building and began monitoring the reactor temperature. They forwarded the temperature data to 

the IC every 15 minutes. 

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. MFG personnel installed a new rupture 

disk, replaced the manway gasket, and tightened the clamps. The IC terminated the fire 

department response activities now that the reactor was resealed. 
 April 2006 

39 

3.0 Incident Analysis 

3.1 Process Chemistry Analyses 

The CSB could not investigate the actual chemical reactions occurring during the incident 

because MFG did not document the actual conditions inside the reactor at the time of the incident. 

The CSB conducted a series of analytical chemical and thermal reactivity tests on the chemicals 

involved in the TAC process to determine if chemical contaminants might have contributed to or 

caused the runaway reaction, quantify the reactive chemistry characteristics of the process, and 

identify and quantify the chemicals that were likely released into the environment. The test 

results are summarized below. A detailed discussion of the methods and results are in Appendix 

A. 

3.1.1 Raw Materials Purity Testing 

The CSB analyzed samples of cyanuric chloride and allyl alcohol from the manufacturing lot 

numbers used by MFG in the production batch using combined gas chromatography and mass 

spectroscopy (GC/MS). The results were compared to high purity samples of the same materials. 

The chromatograms from the production batch were indistinguishable from chromatograms of the 

pure materials. These tests confirmed that the raw materials used in the batch recipe did not 

contain any contaminants that might have caused the runaway reaction. 

3.1.2 Thermal Stability Studies 

Thermo-chemical testing evaluated the desired and undesired chemical reactions that might have 

occurred in the reactor during the incident. Bench-top, adiabatic, and reaction calorimetry 

experiments provided data that assisted in understanding the allyl alcohol/cyanuric chloride 

runaway reaction. The test results indicated that if all of the powdered cyanuric chloride in the 
 April 2006 

40 

reactor had thoroughly mixed with the allyl alcohol and catalyst as planned, the reactor would 

most likely have violently ruptured. 

3.1.2.1 Qualitative Analyses 

Bench-top experiments qualitatively assessed the nature and extent of the reaction resulting from 

mixing the two reactants under different conditions. Experiments examined the effects of 

reactant order-of-addition, the catalyst, and mixture agitation on the reaction. The experiments 

did not use active cooling. A calorimeter recorded the reaction mass temperature as a function of 

time. The results of these experiments demonstrated that the reaction between the allyl alcohol 

and cyanuric chloride is spontaneously exothermic at room temperature regardless of the order of 

addition of reactants, the presence or absence of the catalyst, or whether agitated or not. In the 

absence of adequate cooling and/or control of the rate of chemical addition, the reactants will 

readily generate a runaway reaction. 

3.1.2.2 Reactive Chemistry Analyses 

Adiabatic calorimetry provided data to characterize the temperature and pressure behavior of the 

runaway reaction as a function of time under near-adiabatic conditions25 exhibited in a production 

reactor. The test data permitted calculation of the size of the emergency relief device required to 

protect the reactor vessel from overpressure in the event of a runaway reaction. 

The adiabatic calorimetry testing of the TAC recipe demonstrated the extremely energetic nature 

of the reaction. The tests showed that the reaction progressed very slowly for about 90 minutes, 

after which the temperature rapidly increased at a rate exceeding 500 °F/minute (260 °C/minute) 

with a pressure rise rate approaching 2260 psi/min (155 bar/minute) (Figure 11). Testing 

 

25 Adiabatic refers to any change in which there is no gain or loss of heat. 
 April 2006 

41 

confirmed that the decomposition reaction is highly energetic and capable of causing severe 

damage to equipment. Appendix A, Table 1 summarizes the test results. 

Figure 11. Test cell reaction mass temperature and pressure as a function of time. The 

blowdown vent opened at six bara (75 psig). 

The incident at the MFG facility involved two reactions: (1) the intended synthesis reaction to 

form the TAC product; and (2) an unintended decomposition reaction.26 The reactor was first 

loaded with all of the dry powdered cyanuric chloride, followed by the liquid catalyst, and finally 

the allyl alcohol, filling the reactor to approximately 60 percent of capacity. It is likely that a 

highly non-homogeneous mixture resulted, even after starting the agitator, with much of the solid 

 

26 Decomposition is a chemical reaction that leads to chemicals containing smaller molecules or elements, 

often with the liberation of heat energy and product gasses. 
 April 2006 

42 

and the catalyst remaining on the bottom, tied up in a “sludge” layer. Even with only a portion of 

reagents available for the reaction, the heat produced quickly exceeded the heat removal capacity 

of the reactor cooling system. The increase in temperature then caused the un-reacted allyl 

alcohol to boil,27 pressurizing the reactor. The temperature continued to increase above the 

decomposition temperature. This caused a rapid increase in gas production, further increasing 

reactor pressure until the incorrectly installed manway gasket blew out. The vent rate through the 

manway was not sufficient to keep the reactor pressure below the rupture disc setpoint, and the 

pressure in the reactor increased until the disc ruptured a few seconds later. The maximum 

reactor pressure reached was thus at least 75 psig (five barg), the set point of the rupture disk. 

The peak reactor pressure during the runaway reaction could not be determined.28, 29 

3.1.2.3 Reactor Emergency Vent Analysis 

Applying the data obtained from the calorimetry testing showed that the 4-inch diameter rupture 

disc installed on the reactor was undersized. The CSB determined the minimum vent size for the 

reactor using the American Institute of Chemical Engineers (AIChE) Design Institute of 

Emergency Relief Systems (DIERS) methodology. DIERS is widely accepted in industry as the 

best technology available to determine the pressure relief system requirements for highly reactive 

chemical processes. These usually involve a two-phase flow (i.e., vapor with entrained liquid) 

through the emergency relief device and discharge piping. To vent the reactor properly required 

an opening with 16-inch-diameter rupture disc (See Appendix A). The CSB concluded that the 

reactor vessel did not rupture because the non-homogeneous mixture, discussed above, prevented 

 

27 Allyl alcohol has a normal boiling point of 97 °C (206 °F). 

28 The only pressure instrument on the reactor was a pressure gauge on the reactor head. There was no 

recording device used. 

29 The ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 allows a maximum overpressure 

equal to 110% of the maximum allowable working pressure during emergency venting due to a process 

upset. 
 April 2006 

43 

the reaction from progressing at the rate predicted by the calorimetry testing. In addition, the 

manway gasket leak provided some additional relieving capacity. 

3.1.2.4 Reactor Cooling Analysis 

Reaction calorimetry tests evaluated the reaction heat generated at a predetermined, controlled 

temperature. It measured the instantaneous heat output (power), and the total energy output of 

the reacting chemicals in a laboratory test apparatus. From the results, one can estimate the 

cooling requirements for a full size production reactor. A discussion of the reaction calorimetry 

testing performed is in Appendix A. 

The rate of temperature rise inside the reactor depends on the balance between the rate of heat 

generation due to the reaction, the heat capacity of the chemicals, and the heat removal through 

the cooling jacket. The quantity of heat removed is directly proportional to the difference 

between the temperature of the reactants and the reactor cooling jacket temperature. However, 

the reaction rate increases exponentially with reaction temperature, as shown in Figure 12. If the 

reaction temperature increases beyond a critical point (Figure 12, Point A), the heat generation 

rate will exceed the heat removal rate provided by the reactor cooling jacket—the reaction will 

run away. 

MFG personnel underestimated the heat removal rate required for TAC production because they 

did not consider either the TAC synthesis reaction or the decomposition reaction when they 

evaluated reactor cooling requirements. MFG only evaluated the cooling system requirements 

based on the acid neutralization step that was to occur later in the batch process. Since the 

procedure did not restrict the chemical addition rates, operators charged the reactor with the entire 

quantity of each reactant and the catalyst. The cooling system was unable to control the reactor 

temperature and, as the temperature rose, the decomposition reaction began to dominate, resulting 
 April 2006 

44 

in a runaway reaction. The increasing pressure blew out the manway gasket, and then the rupture 

disk. The vapor continued venting for many hours, until the reaction consumed all the reactants. 

Figure 12. Typical reaction heat production and cooling system heat removal vs. reactor 

temperature. 

3.1.3 Reaction Decomposition Products Analyses 

The CSB team used reaction decomposition product analyses to identify the toxic chemicals that 

were likely released into the atmosphere during the runaway reaction. MFG and Lyondell 

expressed concern about the possible release of hydrogen chloride into the environment because 

it was a known byproduct of the normal TAC reaction chemistry. Gas and vapor sample GC/MS 

analyses collected during the adiabatic calorimeter testing showed that the major compounds 

vented during these tests were allyl alcohol, allyl chloride, carbon monoxide, and a C12

unsaturated compound30 derived from allyl alcohol and/or allyl chloride. The chromatograms and 

the GC/MS data of the runaway reaction products showed no evidence of hydrogen chloride. 

 

30 A C12 unsaturated compound consists of twelve carbon atoms connected by at least one double covalent 

bond. A C12 compound can be a straight chain, branched, or cyclic. 
 April 2006 

45 

Furthermore, the test did not detect cyanuric chloride, or its degradation products, such as 

cyanogen chloride.

3.2 Vapor Cloud Plume Model 

A vapor cloud plume model was developed as part of the CSB investigation to predict the 

endpoint distance31 for the spread of allyl alcohol vapor using the criteria contained in the EPA 

Risk Management Program (Section 4.2.2). The model incorporated the actual weather 

conditions recorded at a nearby meteorological tower. The model assumed that the reactor 

released 6,300 pounds of allyl alcohol, as determined from the reactive chemistry analytical 

results. The calculated endpoint distance of the cloud extended more than three miles downwind 

from the facility. 

The results of the model are comparable to the actual exposure in the community based on the 

symptoms described by the exposed individuals. The CSB could not compare the actual 

conditions to the model because allyl alcohol air concentration measurements were never 

performed in the community and the measurements made at the facility used the wrong test 

apparatus (Section 3.7.2.3). A detailed discussion of the model is in Appendix B. 

3.3 Process Design and Scale-up 

The CSB investigation determined that MFG management did not conduct a comprehensive 

evaluation of the reactive chemistry hazards involved in the TAC production. The process 

development work failed to examine exothermic reactions, so MFG did not learn of the runaway 

potential of their process system. They conducted basic laboratory and pilot plant scale testing to 

 

31 The toxic endpoint is a specific lower concentration of the toxic chemical in air. The EPA toxic 

endpoint for allyl alcohol is 0.036 milligrams per liter (40 CFR 68.22). 
 April 2006 

46 

improve the quality, yield, and reduce costs. Their literature search consisted only of a review of 

patents for the manufacture of TAC, none of which contained any information about the potential 

reactive hazards associated with the process. Had they conducted a thorough literature search,32

they would most likely have identified the thermal and runaway reaction hazards in the TAC 

process as well as important information addressing reactive chemistry scale-up from laboratory 

to production. For example, Designing and Operating Safe Chemical Reaction Processes (HSE, 

2000) discusses the importance of proper scale-up design of process equipment: 

One particular factor...between the heat generated and the heat lost is the effect 

of scale-up from laboratory...to full commercial size...is not always 

appreciated...As reactor scale increases cooling may become inadequate. 

Incidents have occurred when processes are carried out on a plant scale that were 

uneventful in the laboratory. 

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. Lacking these devices, 

operators were unable to mitigate or stop the toxic vapor release. 

3.4 Chemical Addition Rate Control 

MFG personnel did not control the reaction rate using closely controlled, slow addition of the 

chemicals during the batch process. MFG and GPC management personnel had only briefly 

discussed this important reaction-rate control technique, and that was more than one year before 

finalizing the TAC procedure. The final recipe contained no fill rate limitations or warnings. 

Inherently Safer Chemical Processes, (CCPS, 1996) notes: 

 

32 The CSB report Improving Reactive Hazard Management (CSB, 2002) discusses the importance of 

comprehensive literature research as part of the reactive chemistry planning. 
 April 2006 

47 

Semi-batch or gradual addition batch processes limit the supply of one or more 

reactants, and increase safety when compared to batch processes in which all 

reactants are included in the initial batch. For an exothermic reaction, the total 

energy of reaction available in the reactor at any time is minimized. 

During the process development phase of the project, MFG and GPC management discussed the 

hazards associated with the rapid chemical addition into the reactor and acknowledged that it 

could result in significant heat generation (See Section 1.6). However, the final batch procedure 

did not include any limits on the chemical addition rate. During the first production batch on the 

day of the incident, the operators added the total quantity of each chemical all at once, a highly 

dangerous "all-in" approach that maximized the potential for rapid energy release in the reactor. 

3.5 MFG Emergency Management 

The CSB determined that MFG was required to comply with the reporting, emergency planning, 

response, and notification requirements of the EPA Emergency Planning and Community Right 

to Know Act (EPCRA) and Risk Management Program regulations, and the OSHA Hazardous 

Waste Operations and Emergency Response (HAZWOPER) standard. Below is a discussion of 

specific deficiencies identified by the CSB investigation. 

3.5.1 Reporting and Notifications 

In late March 2004, the facility manager informed the Dalton Fire Department that they planned 

to introduce allyl alcohol into the facility for a new chemical trial, as required by EPCRA 

(Section 4.2.1). MFG provided the fire department with a copy of the MSDS and the Lyondell 

Allyl Alcohol Product Safety Bulletin. During that telephone conversation, the deputy fire chief 

informed the plant manager that the fire department was not equipped to respond to a large allyl 

alcohol release because they did not have a fully trained and equipped hazardous materials 
 April 2006 

48 

response team. He informed the manager that MFG would remain responsible for emergency 

response and mitigation in the event of an allyl alcohol release and arranging to have a qualified 

contractor available for both emergency response and spill mitigation. MFG did not implement 

either emergency action plan item. 

3.5.2 Risk Management Program 

MFG management reported that they were aware of the EPA Risk Management Program 

regulation (40 CFR 68) but none of their staff, including the safety and health manager had any 

detailed knowledge or direct experience with it. They simply "overlooked" it and did not check 

the list of covered chemicals, which included allyl alcohol (Section 4.2.2). Had they applied this 

regulation as required, including conducting a comprehensive review of the process and process 

hazard analysis, they would most likely have identified the deficiencies in the TAC procedure, 

process equipment, and emergency shutdown and mitigation equipment. Furthermore, MFG 

would have provided comprehensive information to the local emergency response agencies, 

including the worst case and alternative accident scenarios required by the regulation. That 

information most likely would have better prepared them for the emergency response. 

3.5.3 Emergency Response Plan 

The existing MFG emergency response plan as required by OSHA (Section 4.0) contained a 

general description of the site and liquid containment features beneath the process equipment; a 

discussion of emergency equipment; a list of emergency response actions, including notifications 

and emergency evacuation; and spill prevention and control procedures. However, the CSB 

identified the following deficiencies in the plan: 
 April 2006 

49 

• It 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 CSB concluded that these deficiencies most likely resulted in the exposure of the employees 

to the toxic vapor and the chemical burns sustained by one employee during emergency response 

activities. 

3.6 Product Tolling 

The TAC manufacturing plan was the first tolling arrangement between the two companies and 

the first time MFG handled allyl alcohol. The American Institute of Chemical Engineers Center 

for Chemical Process Safety, Guidelines for Process Safety in Outsourced Manufacturing 

Operations (CCPS, 2000) is an industry recognized "best practice" that provides comprehensive 

guidance for safe tolling operations.33 Had GPC and MFG applied these guidelines, they might 

have prevented or significantly reduced the allyl alcohol release. Although, neither MFG nor 

 

33 As a member of SOCMA, MFG had access through the SOCMA website to the American Chemistry 

Council's Responsible Care Toolkit. Element 4.5 of the Technical Specification Guidance Document 

discusses toll manufacturing best practices. 
 April 2006 

50 

GPC were members, this and other relevant CCPS publications are readily available to industry. 

Furthermore SOCMA (MFG is a member) frequently refers their members to the CCPS 

guidelines. 

3.6.1 Client Responsibilities 

CCPS recommends that the client (GPC) become familiar with the toller’s (MFG) planned 

operation and audit the health, safety, and environmental practices as part of the client's product 

stewardship responsibilities. GPC did not ensure that MFG specifically addressed the hazards of 

production-scale manufacturing of TAC, even though they pointed them out in early discussions. 

The CCPS best practice guidelines recommend that the client ensure that the training program at 

the toller’s facility meets process safety, and environmental risk management training 

recommendations and requirements. GPC did not review the MFG employee-training program, 

nor did it request any proof of adequate training addressing the hazardous chemicals involved in 

the TAC production. 

The guidelines further recommend that the client audit the toller during ongoing operations in 

order to assure that “operations are going as planned and obligations are being met.” GPC did not 

visit the MFG facility, or actively participate in the verification runs or the attempt to make the 

first full-scale production batch. 

Finally, the guidelines list actions to take if the raw materials are not regulated by the Risk 

Management Program or PSM. The guidelines recommend evaluating good process safety 

practices even “when a candidate toller is not currently regulated by a governmental process 

safety requirement and the proposed toll project will not trigger regulation.” Despite MFG 

management's assumption that the TAC process was exempt from PSM compliance and that they 
 April 2006 

51 

overlooked the EPA Risk Management Program regulation, GPC should have ensured that MFG 

had applied good process safety practices. 

3.6.2 Toller Responsibilities 

The CCPS best practice guidelines recommend that the toller share any techniques, information, 

or experience learned as part of the contractual agreement with the client. Additionally, the 

guidelines recommend that the toller discuss and agree on any changes made to the equipment, 

chemicals, technology, or procedure of the tolling arrangement with the client. 

An agreement should be made between client and toller on how change is to be 

managed for a toll....Any change requires the toller and client address the 

hazards and risks associated with the production process. 

MFG did not share all process information with GPC, at least in part for proprietary reasons. 

They only provided a copy of the "final" production-scale procedure to GPC, who assumed that 

MFG knew of the risk of a runaway reaction, and that they would adhere to the procedure, as well 

as slowly add the raw materials into the reactor. However, the procedure used on the day of the 

incident did not match the procedure provided to GPC.34 Furthermore, operators added the full 

production quantity of each raw material to the reactor without considering how that action might 

increase the probability of a runaway reaction. 

Although MFG made specific changes to the original recipe provided by GPC, and GPC was 

aware of those changes, neither company completed and documented the risk assessments. The 

CCPS guidelines recommend that the toller discuss and agree on any changes made to the 

 

34 Only after the accident did GPC become aware that MFG changed the sequence of addition of the raw 

chemicals and that the entire quantity of each was loaded without consideration for controlling the 

reaction. 
 April 2006 

52 

equipment, chemicals, technology, or procedure of the tolling arrangement with the client. “An 

agreement should be made between client and toller on how change is to be managed for a toll.” 

“If covered under U.S. PSM or RMP regulations, any deviation from the original design 

specifications is considered a change." Any change requires the toller and client to address the 

hazards and risks associated with the production process. 

The guidelines also contain specific recommendations for the tolling parties to conduct process 

hazard analyses (PHA) of the tolling project: “For every new tolling situation a process hazard 

analysis should be conducted." The tolling parties should consider all aspects of the toll while 

performing the PHA to identify potential problems caused by the scale-up: 

Simple mixing of raw materials and intermediates may present special problems 

when processing significantly larger quantities in comparison to the pilot process 

or laboratory bench amounts. 

Furthermore, the guidelines recommend augmented observation during scale-up of the critical 

process characteristics that were designed in pilot testing to take into account the order-ofmagnitude changes in vessel size and quantity of materials that may have been engineered into 

the new process: 

When scaling up exothermic or high temperature processes, heat removal 

capability must be considered. The pilot or bench process design may be 

compromised by a lower surface-to-volume ratio. This may be a key factor 

during equipment selection for the scale-up. 

MFG did not adequately evaluate the hazards associated with the scale-up of the process, 

such as evaluation of the heat removal capability of the production reactor compared to 

the bench-scale testing. 
 April 2006 

53 

The following deficiencies were less likely to have occurred had GPC and MFG adequately 

applied the CCPS best practice tolling guidance: 

• MFG did not consider a major toxic release scenario and did not conduct any formal 

hazard assessment. Interviews with plant supervisors revealed that their (and Lyondell’s) 

main areas of concern were the allyl alcohol transfer process and the potential fire hazard 

associated with a small spill. 

• MFG did not anticipate a runaway reaction and make provisions to mitigate a large spill 

or vapor release. The emergency vent on the reactor released the contents directly to the 

atmosphere; it did not safely capture the toxic vapor. 

• MFG did not verify the adequacy of the reactor overpressure relief system. The CSB 

analyses concluded that the required size for the TAC process was as much as 27 times 

larger than the installed relief device. 

• MFG did not prepare an adequate emergency response plan. MFG did not train or 

properly equip employees with appropriate personal protective gear, yet they entered the 

toxic vapor exposure area on multiple occasions. 

3.7 City and County Emergency Management 

The Emergency Planning and Community Right to Know Act (SARA Title III) requires the 

establishment of both state and local emergency planning committees (Section 4.2.1). Local 

emergency planning committees (LEPCs) are responsible for developing comprehensive 

emergency response plans that address hazardous facility identification, emergency notification 

and response procedures, and evacuation plans. The state reviews the completed plan, which 

should be publicized throughout the community. The LEPC is required to review, test, and 

update the plan each year. 
 April 2006 

54 

Whitfield County did not have an established LEPC.35 However, it did have a county Emergency 

Management Agency (Section 4.3.3) as required by the Emergency Management Act of 1981. 

The Whitfield County Emergency Management Agency (EMA) established an Emergency 

Operations Plan (EOP) for managing all emergency response activities. 

3.7.1 Whitfield County Emergency Operations Plan 

The CSB found that the county EOP did not address all of the EPCRA requirements for 

emergency planning and response. Significant shortcomings identified were: 

• 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 (SOP) cited in the EOP, such as community evacuation. 

The EOP contains 17 emergency support functions (ESF) for emergency management planning 

and response. The EOP relies on close coordination among the county Emergency Management 

Center, the county fire department, county sheriff's office, Dalton city fire and police 

departments, the hospital and ambulance service, the American Red Cross, and mutual aid, as 

available, from other county or state agencies. 

Each ESF assigns primary and secondary support responsibilities, requires the development and 

maintenance of standard operating practices, and lists key concepts that the ESF must address. 

 

35 In the mid 1990's Whitfield County emergency response agencies and a few chemical companies, 

including MFG, discussed creating an LEPC. However, interest waned due to lack of funding. 
 April 2006 

55 

The MFG incident primarily involved eight ESFs, of which four had significant shortcomings that 

hindered the evacuation effort. 

• ESF 2: Procedures needed to alert the public in the event of an emergency were not 

developed. There was no automated system, such as emergency sirens or "reverse-911" 

callout equipment to inform the public in the event of an emergency. Police had to go 

door-to-door to alert residents to evacuate. 

• ESF 10: Facility profiles were too general: 

- Offsite toxic exposure distance was not established (other than a half-mile radius 

circle at all but two facilities) and prevailing wind direction was not shown. 

- Community vulnerability studies were not conducted. 

- Only transportation related emergencies were addressed even though hazardous 

substance(s) releases were listed for 38 fixed facilities. 

• ESF 17: Communication resources were only in English. Many of the evacuees 

impacted by the MFG incident only spoke Spanish. 

City, county, state, and federal agencies rely on facility-specific hazard data in the event of a 

release. Incomplete, conflicting, or out-of-date information addressing toxic hazards in a 

community can significantly degrade the ability to respond safely to an incident. The CSB 

identified the following shortcoming: 

• The company-specific hazardous chemical information contained in the Whitfield County 

Emergency Response Plan on file in the county EMA office and on file at the Georgia 

Department of Natural Resources, Environmental Protection Division (EPD) was not upto-date. The MFG updated information addressing the chemicals used in the TAC 

process was never provided to the EPD. 
 April 2006 

56 

3.7.2 City and County Emergency Response 

Lack of LEPC participation in developing a comprehensive county Emergency Response Plan 

may have contributed to the significant number of individuals that required decontamination and 

treatment for exposure to toxic chemicals released from the MFG facility. The Dalton fire and 

police departments, the ambulance staff, and the hospital staff were not aware of the potential of a 

major toxic chemical release and were not fully prepared to respond. 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. Contaminated individuals had to travel five miles beyond the evacuation zone to be 

decontaminated; personnel did not collect and handle the water used to rinse off the contaminated 

individuals as hazardous waste. 

3.7.2.1 Toxic Chemical Exposure Hazard 

The CSB determined that the fire department incident command should have directed all 

emergency response personnel to remain a safe distance away from the advancing toxic vapor 

cloud. This would have significantly reduced the toxic chemical exposure received by the 

emergency responders. The IC advised police officers to enter the neighborhoods to begin 

notifying the residents of a precautionary evacuation. However, even though informed by the 

dispatcher that strong noxious vapor was severely hindering police evacuation activities in the 

neighborhoods, the IC did not advise them to leave the exposure area for many minutes. More 

than 15 police and ambulance personnel responding to the scene were directly exposed to the 

allyl alcohol vapor when they drove into the vapor cloud while attempting to evacuate the 

residents (See Section 2.3.3). None of the exposed individuals had the necessary personnel 

protective equipment to prevent contamination when they entered the rapidly expanding toxic 
 April 2006 

57 

cloud. A properly trained and equipped hazmat response team should be the only personnel 

allowed to enter a contaminated area, not police and ambulance crews. 

3.7.2.2 Evacuation Notification 

The CSB investigation found that the city and county lacked effective methods to promptly alert 

the public and keep them informed during the emergency evacuation. Having no automated 

notification systems such as automatic telephone dialing systems, siren systems, or radio and TV 

announcement procedures delayed the evacuation.36 The notification and verification process 

took approximately two hours, which extended the period of public exposure. 

Emergency evacuation instructions were only in English, yet many of the residents primarily 

spoke Spanish.37 The evacuation notification process also failed to provide any specific 

instructions to the evacuees concerning the evacuation routes, or for obtaining updated 

information on the status of the evacuation. Additionally, many residents claimed that they were 

never notified when the evacuation order was lifted, causing confusion among the residents and 

delaying their return to their homes.38 Residents also complained that they did not receive 

guidelines for decontaminating their personal belongings, including any food potentially exposed 

to the toxic vapor that entered their houses. 

3.7.2.3 Air and Water Toxic Chemical Monitoring 

The Dalton 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 (see 

 

36 Oak Ridge National Laboratory has conducted studies that show that evacuations using the door-to-door 

method take 2.5 to 3 hours, but only take 20 to 35 minutes using combined sirens and an Emergency 

Broadcast System (Sorensen, 1988). 37 Families that primarily spoke Spanish reported to CSB investigators that they had to rely on young multilingual children to translate the evacuation information for their parents. 

38 At least one local radio station broadcast announcements that the evacuation order was lifted. 
 April 2006 

58 

Section 1.5.1). Fire department personnel would be exposed to many thousands of parts per 

million of the toxic gas before the oxygen depletion alarm would have sounded. 

The CSB found that 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. When 

finally initiated, this monitoring was ineffective because the lower detection limit of the test 

device was too high for the chemicals released.39 In addition, the only air sampling performed 

was near the MFG facility; there was no air sampling in the affected community. 

MFG employees suffered exposure to unknown concentrations of the toxic vapor. One employee 

sustained chemical burns from his exposure (See Section 2.3.6 ). The National Response Team40

considers that it is “crucial” to monitor the release and to assess its impact as soon as possible. 

Decisions about response personnel safety, citizen protection (whether to be sheltered or 

evacuated), and the use of food and water in the area are dependent on an accurate assessment of 

spill or plume movement and concentration. Decisions about containment and clean up also 

depend on air and water exposure monitoring (NRT, 2001). Furthermore, OSHA requires 

emergency response personnel to use positive-pressure SCBA for emergency response activities 

involving hazardous substances that present an inhalation hazard, until the IC determines through 

the use of air monitoring that a decreased level of respiratory protection will not result in 

hazardous exposures [29 CFR 1910.120(q)(3)(iv)]. 

 

39 Air sampling was performed with generic alcohol sensitive "Drager Tubes”. They had a minimum 

detection threshold limit of 20 ppm, ten times greater than the OSHA PEL and the same value as the 

IDLH concentration (see Section 1.5). 

40 The U.S. National Response Team is an organization of 16 Federal departments and agencies responsible 

for coordinating emergency preparedness and response to oil and hazardous substance pollution 

incidents. The Environment Protection Agency (EPA) and the U.S. Coast Guard (USCG) serve as Chair 

and Vice Chair respectively. (See 49 CFR 300). 
 April 2006 

59 

3.7.2.4 Toxic Chemical Contamination Beyond the Evacuation Zone 

The CSB concluded that the decontamination area should have been established as close to the 

incident scene as possible to minimize the exposure and contamination from the toxic chemical. 

The National Response Team recommends establishing standard operating and decontamination 

procedures for protecting the safety of emergency response personnel from the risks posed by 

hazardous materials, and minimizing the spread of the toxic material (NRT, 2001). The only 

decontamination area was set up at the hospital, more than five miles away from the evacuation 

zone. Responders transported exposed individuals in ambulances from the triage station to the 

hospital, leading to EMT and paramedic exposure to the toxic chemical, as well as contamination 

of the triage area and the ambulances. 
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60 

4.0 Regulatory Analysis 

4.1 OSHA 

Federal OSHA administers and enforces worker safety and health standards in Georgia. Prior to 

the April 2004 incident, OSHA had never conducted an inspection at MFG. The post-incident 

inspection conducted by OSHA did not address PSM program elements. 

4.1.1 Process Safety Management 

The CSB concluded that MFG should have applied the OSHA Process Safety Management 

(PSM) standard to isotainer and the TAC process equipment. The PSM standard requires 

employers to prevent or minimize the consequences of catastrophic releases of highly hazardous 

chemicals. PSM applies to processes that involve listed toxic chemicals at, or above threshold 

quantities and processes with flammable liquids or gases onsite, in one location, in quantities of 

10,000 pounds or more. Although the standard contains certain exemptions, none applied to the 

MFG TAC process or isotainer. 

4.1.1.1 Threshold Quantity in the TAC Reactor 

The MFG decision to limit the allyl alcohol quantity in the TAC reactor to avoid PSM 

compliance was technically correct. The MFG TAC fixed process equipment contained 9,900 

pounds of allyl alcohol, one percent below the 10,000-pound regulatory threshold limit. OSHA 

suggests in the preamble to the PSM standard that reducing the quantity of a hazardous material 

below the threshold quantity might be an acceptable approach to reducing the potential hazard 

and avoiding application of the PSM standard (57 FR 6356, pg 16, 1992). The listed threshold 

quantity of a flammable liquid or listed toxic chemical is used to determine only if PSM 

compliance is required. The threshold quantity does not establish whether a process involving a 
 April 2006 

61 

specific quantity of a covered chemical is safe or unsafe. The CSB concluded that the 

insignificant reduction applied by MFG did not reduce the potential process hazards as 

envisioned when OSHA published the guidance. 

4.1.1.2 Flammable Liquid Exemption 

MFG incorrectly concluded that the allyl alcohol in the isotainer was exempt from the PSM 

standard as provided in the flammable liquid exemption criteria: "Flammable liquids stored in 

atmospheric tanks or transferred which are kept below their normal boiling point without the 

benefit of chilling or refrigeration" [§1910.119 (a)(ii)(B)]. The CSB concluded that the 

exemption did not apply because isotainers41 with a design pressure exceeding 0.5 psig do not 

meet the PSM definition of an "atmospheric tank" [§1910.119 (b)]. Furthermore, since the 

isotainer remained parked less than 20 feet away from the process equipment, and the transfer 

hose remained attached to the (otherwise non-covered) reactor and process equipment, the 

process equipment was subject to the PSM standard. 42

4.1.2 Hazardous Waste Operations and Emergency Response 

The Hazardous Waste Operations and Emergency Response standard (HAZWOPER) §1910.120 

requires that if employees are expected to perform emergency response activities, the employer 

must prepare and implement an emergency response plan. The plan is required to address 

emergency response procedures, training, and personnel decontamination for each functional 

performance level defined in the standard. The MFG emergency response plan did not address 

 

41 The isotainer was a DOT Specification IM101 cargo tanker. The design pressure was approximately 90 

psig. 

42 OSHA intends that "boundaries of a process extend to quantities in storage, use, manufacturing, 

handling,...which are interconnected..." (57 FR 6356, Preamble to the PSM Standard, pg 36, 1992). 
 April 2006 

62 

the HAZWOPER "Hazardous Materials Technician" tasks,43 which enable trained and equipped 

individuals to respond to releases or potential releases. During the incident, employees without 

training or proper personnel protective equipment attempted to mitigate the release. 

Consequently, one MFG employee sustained chemical burns while performing hazardous 

material technician emergency response activities. 

4.2 EPA 

4.2.1 Emergency Planning and Community Right to Know Act 

In 1986, Congress passed the Superfund Amendments and Reauthorization Act (SARA). SARA 

established a national baseline for planning, response, management, and training for chemical 

emergencies. Title III of SARA, the Emergency Planning and Community Right-to-Know Act 

(EPCRA), is intended to promote state and local government hazardous chemical emergency 

preparedness and response capabilities through better coordination, planning, and access to 

chemical information. EPCRA Section 302 requires the governor of each state to establish a 

State Emergency Response Commission (SERC), which is responsible for implementing EPCRA 

provisions. The SERC designates emergency planning districts and appoints local emergency 

planning committees (LEPC) for each district. Each LEPC is responsible for developing an 

Emergency Response Plan as set forth in EPCRA Section 303. 

LEPCs use chemical inventory information from facilities handling hazardous chemicals to 

participate in the development of comprehensive local emergency response plans. The EPA 

 

43 Hazardous Materials Technician - trained individuals who are equipped to respond to releases or 

potential releases. They assume a more aggressive role than a first responder at the "Operations Level" 

in that the hazardous materials technician will approach the point of release in order to plug, patch, or 

otherwise stop the release of a hazardous substance. 
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requires that participants in the LEPC include not only emergency response authorities and 

representatives of facilities that use covered chemicals, but also community representatives such 

as local hospital personnel, the media, environmental groups, and residents. Broad participation 

in the LEPC ensures that emergency response planning takes into account all of the community 

issues in the event of an actual chemical emergency. The LEPC may also participate in natural 

disaster emergency response planning. 

The SERC supervises and coordinates the LEPC activities, establishes procedures for receiving 

and processing public requests for information collected under EPCRA, and reviews local 

emergency response plans. Although the EPA has no mandatory oversight authority, their 

regional response teams may review and comment on an emergency response plan or other issues 

related to preparation, implementation, or exercise of the plan when requested to do so by an 

LEPC. 

Section 303 of EPCRA requires each LEPC to prepare an emergency response plan (ERP) and 

submit a copy to the SERC for review and comment. The ERP must: 

• Document the name and location of each business in the community that has more than 

specified quantities of “extremely hazardous substances”, 

• Develop procedures for the business and local emergency and medical personnel to use 

when responding to a hazardous chemical release, 

• Assign emergency coordinators for both the business establishment and the community, 

• Develop procedures for notifying the community that there has been a hazardous 

chemical release, and 

• Develop evacuation plans that include effective notification methods and evacuation 

routes. 
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Facilities covered under EPCRA, such as the MFG facility, are required to submit emergency and 

hazardous chemical information to the LEPC, the SERC, and the local fire department. LEPCs 

are to have access to the facility Risk Management Plans (Section 4.2.2) and to work with 

industry and local officials to improve local emergency response plans and to inform the public 

about chemical accident hazards and risks. 

Whitfield County has not established an LEPC. The county’s Emergency Management Agency is 

responsible for the emergency response plan (the Whitfield County EOP). The CSB investigation 

identified a number of deficiencies in the county emergency response as discussed in Section 3.7. 

It is possible that if Whitfield County had an LEPC with active participation by the community 

and companies that use covered chemicals, it may have prevented many of the problems 

involving community notification, evacuation procedures, and coordination among responding 

agencies that were encountered during the MFG incident. 

4.2.2 Risk Management Program 

The EPA Risk Management Program regulation (40 CFR 68), mandated by Section 112(r) of the 

Clean Air Act Amendments of 1990, regulates the use of highly hazardous chemicals at facilities 

(stationary sources44). The purpose is to prevent accidental releases of these substances and to 

ensure that the company and community are able to respond effectively in the case of a release. 

The regulation applies to facilities that use or store regulated substances that exceed the threshold 

quantity defined in the EPA regulations. 

The TAC process fell under the Risk Management Program regulation because MFG took 

delivery of 35,000 pounds of allyl alcohol, more than twice the 15,000-pound threshold 

 

44 Stationary sources include transportation containers (e.g. the isotainer) no longer in transit. 
 April 2006 

65 

quantity.45 Covered facilities are required to develop a Risk Management Program and submit 

the Risk Management Plan (RMP), a summary of the facility’s Risk Management Program, to the 

EPA before receiving the covered chemical on site. The EPA then delivers each RMP to the 

responsible state agency. Each state agency is required to make the RMP information available to 

the affected LEPC or county emergency management agency. The EPA may enforce the Risk 

Management Program regulation directly or may delegate the authority to a state agency, as is the 

case in Georgia. 

The Risk Management Program consists of three parts: 

• Hazard assessment that details the potential effects of an accidental release, an accident 

history for the last five years, and an evaluation of worst-case and alternative accidental 

releases; 

• Prevention program that includes safety precautions and maintenance, monitoring, and 

employee training measures; and 

• Emergency response program, detailing emergency health care, employee training 

measures, and procedures for informing the public and response agencies (e.g., the fire 

department) in the event of a release. 

The facility-specific hazard information contained in the Risk Management Plans enables local 

governments and the public to understand what each company is doing to minimize the likelihood 

of a release. Furthermore, the information helps fire, police, and emergency response personnel, 

with assistance from the LEPC to develop a comprehensive emergency response plan to minimize 

the impact of a chemical release on the community. 

 

45 The TAC process would most likely have been covered as "Program 3" because the process was covered 

by the PSM standard and the worst case scenario would have identified off-site receptors (Appendix B). 
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MFG management should have implemented the Risk Management program for the TAC 

process. Under the program, they should have prepared and communicated a comprehensive 

written emergency plan to local authorities as well as training their own personnel in the 

appropriate emergency response. By not implementing the program before receiving the allyl 

alcohol, MFG contributed to the city and county emergency planning and response shortcomings 

(see Section 3.5.2). 

4.3 Georgia Regulations 

4.3.1 Georgia Department of Natural Resources, Environmental 

Protection Division 

The Georgia Department of Natural Resources (GDNR), Environmental Protection Division 

(EPD) is responsible for administering the EPCRA requirements in the state and serves as staff to 

the State Emergency Response Commission. The EPD has access to and reviews chemical 

inventory data, and identifies facilities that have not filed documents required by EPCRA. The 

EPD is also responsible for receiving reports of chemical releases and enforcing the requirements 

of the EPA Risk Management Program regulation. This includes processing written requests for 

a copy of the nearly 400 facility RMP submittals, an important data source for emergency 

planning at the local level as discussed in Section 4.2.2. It makes RMPs available to LEPCs (and 

county emergency response agencies) upon request. However, the Georgia EPD reported that 

neither Whitfield County nor the City of Dalton had requested RMP submittal data for the 

covered facilities in the county or city. 

The Georgia EPD has the authority, as provided through the Clean Air Act, to conduct 

compliance inspections at any facility that is required to conform to the EPA Risk Management 

Program regulation. Shortly after the MFG incident, EPD personnel acknowledged that 
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67 

inspections had been infrequent, and the facility management usually received advance 

notification of planned inspections.46 

4.3.2 Georgia Emergency Response Commission 

The governor of Georgia created the Georgia (State) Emergency Response Commission (SERC) 

within the EPD in 1987 in response to the requirements of SARA Title III. Instead of 

establishing an LEPC in each county that contained facilities that handled large quantities of 

hazardous chemicals, as envisioned (but not required) by the federal regulations, the governor 

initially established a single statewide LEPC to cover all 159 counties. The state now encourages 

each county to establish an LEPC. The CSB found that as of June 2005, Georgia reported 21 

LEPCs were in place. Ten additional LEPCs were in the process of formation.47 

Where LEPCs exist, companies covered by EPCRA send their Tier II48 information to the LEPCs, 

fire departments, and the SERC. Counties lacking an LEPC send the required information to the 

fire department and the SERC. The SERC by-laws state that they review the local emergency 

response plans. However, staff stated that the emergency response plan oversight required by 

EPCRA is the responsibility of Georgia Emergency Management Agency (Section 4.3.3). 

The CSB found that even though the SERC had been in place for more than 18 years, the 

commission had not developed any written procedures or guidelines for conducting the plan 

reviews. Furthermore, it had conducted no formal meetings between 2001 and April 12, 2004, 

the date of the MFG incident. 

 

46 EPD reported to the CSB that as of the end of 2005, they had conducted initial compliance inspections at 

all of the "more than 350 facilities in the state that have filed an RMP." EPD further claimed that staff 

had completed second inspections at approximately 20% of the facilities. 

47 As of June 2005, the U.S. EPA website listed only 16 LEPCs in Georgia. 

48 Companies must report to the local emergency response organization the total on-site quantity of each 

chemical listed in the Tier II extremely hazardous chemical list. 
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68 

4.3.3 Georgia Emergency Management Agency 

The Georgia Emergency Management Agency (GEMA), created under the Georgia Emergency 

Management Act of 1981, has the authority to exercise overall direction and control of 

emergency or disaster operations in the Georgia as required by the Federal Emergency 

Management Agency (FEMA). The GEMA director is responsible for the statewide emergency 

management program elements mandated by FEMA regulations and is responsible for overseeing 

each county’s development of an “All Hazards Plan” required by FEMA. All Hazards Plans are 

required to address chemical releases, transportation incidents, natural disasters, and terrorist 

actions, and comply with the EPCRA and FEMA requirements. 

Each county in Georgia must include any information required by EPCRA emergency response 

plan requirements, as an attachment to their All Hazards Plan (Emergency Operations Plan), 

although GEMA does not review the content of the submissions for compliance with EPCRA 

requirements. In addition, each county is required to develop Standard Operating Procedures that 

accompany the hazard plan. GEMA does not review the SOPs. 

GEMA shares responsibility with the EPD for encouraging counties to establish LEPCs and 

monitoring their activity. Because of the overlapping emergency planning responsibilities 

between SERC and GEMA, GEMA was to serve as the planning unit for the SERC. 

The Georgia Emergency Management Act of 1981 requires all counties to create an Emergency 

Management Agency (EMA). Each EMA is required to develop and submit an Emergency 

Operations Plan to GEMA. The plan identifies the responsibilities of the county officials during 

an emergency but contains limited details about individual facilities. The EMA also has the 

responsibility to develop the All Hazards Plan and submit it to the EPD. Although the CSB 

identified deficiencies in the Whitfield County emergency operations plan (See Section 3.7.1), the 

county had never received any plan review comments from GEMA or EPD. 
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5.0 Similar Incidents 

A joint OSHA/EPA report and two recent CSB reports discuss industrial incidents with many 

similarities to the MFG incident. Two incidents discussed in Bretherick’s Handbook of Reactive 

Chemical Hazards [Urben, et al., 1999] directly involved TAC manufacturing. The CSB 

investigation concluded that had MFG been aware of these incidents, they would have had a 

better understanding of the reactive chemistry hazards involved in manufacturing TAC. 

5.1 Napp Technologies 

In April 1995, an explosion and fire at Napp Technologies, in Lodi, New Jersey, killed five 

employees and injured several others, destroyed much of the facility, and significantly damaged 

nearby businesses. More than 300 residents and a nearby school required evacuation for almost 

24 hours. Additionally, water used to suppress the fire mixed with chemicals at the facility and 

flowed into the Saddle River, causing a fish kill. 

Napp had contracted with another company to provide toll manufacturing of a special chemical 

mixture using aluminum powder, sodium hydrosulfite, potassium carbonate, and benzaldehyde. 

A runaway reaction resulted following the inadvertent introduction of water into a mixer 

containing aluminum powder and sodium hydrosulfite, both of which are water reactive, 

combustible solids. 

The EPA and OSHA joint accident investigation team identified the following contributing 

factors (U.S. EPA/OSHA, 1997): 

• Inadequate communications between Napp and the tolling contractor, 

• Inadequate process hazard analysis, 

• Less than adequate operating procedures and personnel training, 

• Inadequate training of Napp employees who were emergency responders. 
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5.2 Reactive Hazard Management 

The CSB report Hazard Investigation: Improving Reactive Hazard Management (USCSB, 

2002b), examined chemical process safety in the United States—specifically hazardous chemical 

reactivity. The data analyzed included 167 serious incidents in the United States involving 

uncontrolled chemical reactivity from January 1980 to June 2001. Forty-eight of these incidents 

resulted in 108 fatalities. Approximately 30 percent of the incidents directly affected the public 

i.e., documented injury, community evacuation, or shelter-in-place. 

Key findings in the CSB reactive chemical report closely parallel the MFG incident findings: 

• More than 60 percent of the incidents for which some causal information was available 

involved inadequate practices for identifying hazards or conducting process hazard 

evaluations, 

• More than 90 percent of the incidents involved reactive hazards that are documented in 

publicly available literature accessible to the chemical processing and handling industry. 

5.3 Incidents Directly Involving TAC Manufacturing 

Bretherick’s Handbook of Reactive Chemical Hazards list two incidents involving mixtures of 

cyanuric chloride and allyl alcohol from reports originally published in the Institution of 

Chemical Engineers Loss Prevention Bulletin. The incidents are similar to the MFG incident 

even though there was no ignition of the flammable vapors at MFG. 

5.3.1 Early 1970s Overpressure and Fire Incident 

A company was attempting to make TAC in a 2000-liter (528 gallon) reactor charged with 

cyanuric chloride, allyl alcohol, and water. A runaway chemical reaction occurred due to 

inadequate cooling of the contents in the reactor. The rapidly rising temperature and pressure 

caused the reactor rupture disc to burst and the manway gasket to dislodge. Allyl alcohol vapors 
 April 2006 

71 

escaped and subsequent ignition caused an explosion and flash fire. Four people sustained minor 

injuries. 

5.3.2 1979 Attempt to Manufacture TAC 

A runaway chemical reaction occurred when operators were charging cyanuric chloride into an 

allyl alcohol/water mixture in an attempt to manufacture TAC. Operators failed to provide 

adequate cooling to the contents of the reactor. Pressure generated in the reactor caused the 

manway gasket to fail. Approximately 400 kilograms (880 pounds) of allyl alcohol vapor 

escaped and ignited, causing a severe explosion. 
 April 2006 

72 

6.0 Industry Associations 

6.1 Synthetic Organic Chemical Manufacturers Association 

6.1.1 Responsible Care 

In 1989, the American Chemistry Council (ACC) developed the Responsible Care Process Safety 

Code for use by the member companies. The Code includes management system elements 

designed to prevent fires, explosions, and accidental chemical releases. The Synthetic Organic 

Chemical Manufacturers Association (SOCMA) adopted the Responsible Care Process Safety 

Code in 1990 for use by their member companies.49 

As an active member in SOCMA, MFG management implemented the Responsible Care Code at 

their two facilities and conducted self-assessments as required by the program. The CSB 

reviewed the Responsible Care self-assessments performed by MFG prior to the incident. The 

self-assessments were conducted for the Process Safety program, the Environmental Health & 

Safety (EH&S) program, the Product Stewardship program, and the Community Awareness and 

Emergency Response (CAER) program. Each MFG self-assessment concluded that the programs 

were adequate. However, the CSB investigation identified significant deficiencies, as previously 

discussed in Section 1.7.2 

6.1.2 Reactive Chemicals Hazards Awareness 

The CSB report Hazard Investigation: Improving Reactive Hazard Management (USCSB, 

2002b) published more than two years before the MFG incident recommended SOCMA 

 

49 In September 2005, SOCMA replaced the Responsible Care Code with a new program named 

ChemStewards. SOCMA believes that broad participation from its members in the new program "will 

lead to a safer, more secure chemical manufacturing sector." 
 April 2006 

73 

"communicate the findings and recommendations of the report to their membership." SOCMA 

formally responded to the CSB report recommendation by highlighting the report findings in two 

editions of their membership newsletter (September 20 and 27, 2002) and by posting a web link 

to the CSB online version of the report on their member web page. However, MFG management 

stated that they were not aware of the CSB report and they did not see the newsletter articles or 

the web link provided through SOCMA. 

Had MFG reviewed the CSB report, they likely would have had a better awareness of the hazards 

associated with reactive chemicals. A more rigorous process safety review and control of the 

reaction rate by MFG could have prevented the incident or, at least minimized the toxic chemical 

release. 

6.2 AIChE/CCPS Tolling Guidance 

The American Institute of Chemical Engineers (AIChE) is a professional organization that 

provides chemical process safety guidance to individuals in the chemical industry through 

education, training, and outreach. The AIChE Center for Chemical Process Safety (CCPS) is a 

major source of chemical process information. CCPS works with industry to develop engineering 

and management practices to prevent or mitigate catastrophic releases of hazardous materials. 

CCPS publishes guidelines for a variety of chemical safety issues. The intent of the tolling 

process safety guidelines in Guidelines for Process Safety in Outsourced Manufacturing 

Operations (CCPS 2000) is to help minimize risk and improve safety for the companies involved, 

the public, and the environment. These guidelines are available to SOCMA member companies. 

Had MFG (a SOCMA member) and GPC applied the tolling process safety guidelines discussed 

in Section 3.6, many of the deficiencies identified by the CSB that led to the incident could have 

been avoided. 
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7.0 Root and Contributing Causes 

The Logic Tree (Appendix C) graphically displays the progression from the top event, personnel 

injury from exposure to a toxic chemical, to the management systems root and contributing 

causes. 

7.1 Root Causes 

1. MFG did not understand or anticipate the reactive chemistry hazards. They did not 

make use of readily available literature on the hazards of reactive chemistry, or 

conduct a comprehensive literature search of the reactive chemistry hazards involved 

in TAC production, which would have alerted them to the hazards involved in 

manufacturing TAC. For example, Bretherick’s Handbook of Reactive Chemical 

Hazards, (Urben, et al ., 1999), a well-known reference publication on reactive 

chemical process design, includes TAC production hazards and previous TAC 

incidents. 

2. MFG did not perform a comprehensive process design and hazard review of the 

laboratory scale-up to full production before attempting the first TAC batch: 

• They did not evaluate or control the rate of chemical addition into the reactor. 

• They did not evaluate the primary TAC reaction chemistry, heat generation and 

process cooling requirements for the production batch. 

• They did not consider or provide critical process controls or alarms, such as high 

pressure or high temperature alarms. 

• They did not install and use toxic material containment devices, such as an 

emergency vent vapor-collection system to control or mitigate a toxic release. 

• They did not evaluate the reactor overpressure relief system. 
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75 

3. The MFG emergency response plan was inadequate. MFG did not train or equip 

employees to conduct emergency mitigation actions. 

4. MFG did not implement the EPA Risk Management Program or the OSHA Process 

Safety Management program prior to receiving the allyl alcohol. The regulations 

require comprehensive engineering analyses of the process, emergency planning, a 

pre-startup safety review, and coordination with the local community before receiving 

the covered chemical at the site and introducing the covered chemical into the process. 

7.2 Contributing Causes 

1. 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). 

2. The City of Dalton emergency response planning did not adequately address a toxic 

release at a fixed facility. 

• City Fire Department procedures did not adequately address incident scene hot 

zone access control. 

• City Police Department procedures did not adequately address measures to 

protect emergency response personnel against toxic exposure during entry into a 

known, or suspected hazardous area. 
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76 

3. The Whitfield County Emergency Operations Plan did not adequately anticipate or 

address the specific problems associated with this incident. 

• The plan did not adequately address important emergency response activities 

such as shelter-in-place, evacuation planning, and notification. During the MFG 

incident evacuation, the notification process relied only on door-to-door 

notification. 

• The emergency planning process did not involve community and business 

participation to ensure adequate preparation for responding to emergencies 

involving hazardous chemicals. 

4. The Georgia EPD did not review the Whitfield County Emergency Operations Plan. 

The Georgia EMA review did not address the EPCRA elements. A more 

comprehensive review by these two state agencies may have identified the 

deficiencies in the emergency planning and response procedures. 
 April 2006 

77 

8.0 Recommendations 

8.1 MFG Chemical, Inc. 

2004-09-I-GA-R1 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. 

2004-09-I-GA-R2 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. 

2004-09-I-GA-R3 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. 

2004-09-I-GA-R4 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. 
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78 

8.2 GP Chemical 

2004-09-I-GA-R5 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, 

• Active participation in the first production run, as appropriate. 

8.3 Lyondell Chemical Company 

2004-09-I-GA-R6 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. 

2004-09-I-GA-R7 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. 
 April 2006 

79 

8.4 City of Dalton 

2004-09-I-GA-R8 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. 

2004-09-I-GA-R9 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. 

8.5 Whitfield County 

2004-09-I-GA-R10 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, 

• Educate the community regarding proper protective actions, such as 

shelter-in-place and evacuation procedures. 
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2004-09-I-GA-R11 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, 

• Implement an automated community emergency notification system. 

8.6 Governor of the State of Georgia 

2004-09-I-GA-R12 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. 

2004-09-I-GA-R13 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. 
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81 

8.7 Synthetic Organic Chemical Manufacturers Association 

2004-09-I-GA-R14 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. 

2004-09-I-GA-R15 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. 

2004-09-I-GA-R16 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. 
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82 

9.0 References 

American Industrial Hygiene Association, 1989. Odor Thresholds for Chemicals with 

Established Occupational Health Standards, AEAR89-108, 1989. 

American Petroleum Institute, 2000. Sizing, Selection, and Installation of Pressure-Relieving 

Devices in Refineries: Part I - Sizing and Selection, API 520, January 2000. 

Baker Engineering and Risk Consultants, Inc., 2005. U.S. Chemical Safety and Hazard 

Investigation Board, Report No. 01-00987-001-04, Thermal Reactivity Testing and Analytical 

Chemical Evaluation for Incident CSB 2004-09-I-GA (MFG Chemical), February 25, 2005. 

Baker Engineering and Risk Consultants, Inc., 2006. U.S. Chemical Safety and Hazard 

Investigation Board, Report No. 01-01143-001-05, Modeling Release at MFG Chemical, Dalton, 

GA CSB 2004-09-I-GA (MFG Chemical), January 16, 2006. 

Brown, D.F., W.A. Freeman, R.A. Carhart, and M. Krumpole, 2005. Development of the Table of 

Initial Isolation and Protective Action Distances for the 2004 Emergency Response Guidebook, 

Argonne National Laboratory report ANL DIS-05-02, pp. 75-77, May 2005. 

Center for Chemical Process Safety (CCPS), 1996. Inherently Safer Chemical Processes, A Life 

Cycle Approach, American Institute of Chemical Engineers, 1996. 

CCPS, 2000. Process Safety in Outsourced Manufacturing Operations, American Institute of 

Chemical Engineers, 2000. 

Health and Safety Executive (HSE), 2000. Designing and Operating Safe Chemical Reaction 

Processes, Norwich, U.K., HSE Books, 2000. 

International Code Council, Inc, 2000. International Fire Code, 2000. 
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83 

Johnson, Robert W., et al., 2003. Essential Practices for Managing Chemical Reactivity 

Hazards, Center for Chemical Process Safety, 2003. 

Kriebitzsch, N., and H. Klenk, 2002. “Cyanuric Acid and Cyanuric Chloride”, Ulmann’s 

Encyclopedia of Industrial Chemistry, Volume A.8., pages 191-200, Wiley-VCH Verlag GmbH 

& Co, 2002. 

Lewis, Richard J., Sr., 1996. Sax’s Dangerous Properties of Industrial Materials, Ninth Edition, 

Van Nostrand Reinhold, NY, 1996. 

Lyondell Chemical Company, 2002. Allyl Alcohol Material Safety Data Sheet #BE221, Version 

1.4, 3/25/2002. 

Lyondell Chemical Company, 2004. Allyl Alcohol Product Safety Bulletin, Revision 3, 2004. 

National Response Team, 2001. Hazardous Materials Emergency Planning Guide, NRT-1, 2001. 

Pohanish, Richard P. and Stanley A. Green, 2003. Wiley Guide to Chemical 

Incompatibities, John Wiley & Sons, 2003. 

Sorensen, J.H. 1988. Evaluation of Warning and Protective Action Implementation Times for 

Chemical Weapons Accidents, (Report prepared for the Office of Program Executive Officer, 

Aberdeen Proving Ground, MD), Oak Ridge National Laboratory, Oak Ridge, TN, 1988. 

U.S. Chemical Safety and Hazard Investigation Board (USCSB), 2000. Investigation Report: 

Chemical Manufacturing Incident, Morton International, Inc, Report No. 1998-06-I-NJ, August 

2000. 

USCSB, 2002a. Case Study, The Explosion at Concept Sciences: Hazards of Hydroxylamine, 

Report No. 1999-I2-C-PA, February 2002. 
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84 

USCSB, 2002b. Hazard Investigation: Improving Reactive Hazard Management, Report No. 

2001-01-H, September 2002. 

USCSB, 2003. Investigation Report: Explosion and Fire, First Chemical Corporation, Report 

No. 2003-01-I-MS, October 2003. 

USCSB, 2004. Case Study: Explosion at Biochemical Facility: Liquid Nitric Oxide Release, 

Isotec Report No. 2003-I5-C-OH, August 2004. 

U.S. Department of Labor, Occupational Safety and Health Administration (OSHA), 1992. 

Preamble to the Process Safety Management standard, 57 FR 6356, 1992. 

OSHA, July 11, 1994. Standard Interpretations, 1910.119, Letter to American Institute of 

Chemical Engineer[s], Lakeland, FL, 1994. 

OSHA, 1997. Secretary of Labor vs. Meer Corporation, OSHRC Docket No. 95-0341, 1997. 

U.S. Department of Transportation (USDOT), Research and Special Programs Administration, 

2003. Applicability of the Hazardous Materials Regulations to Loading, Unloading and Storage,

Final Rule, Federal Register Vol. 68, No. 210, October 30, 2003. 

USDOT, 2004. Emergency Response Guidebook, 2004. 

U.S. EPA/OSHA, 1997. Joint Chemical Accident Investigation Report, Napp Technologies, Inc., 

Lodi, New Jersey, EPA 550-R-97-002, 1997. 

Urben, Leslie P. G., and Martin J. Pitt, 1999. Bretherick’s Handbook of Reactive Chemical 

Hazards, Sixth Edition, Vol. 1, Butterworth-Heinemann, 1999. 
 Appendices April 2006 

85 

Appendix A 

MFG Triallyl Alcohol Process Chemistry Analyses
 Appendices April 2006 

86 

Appendix A 

MFG Triallyl Alcohol Process Chemistry Analyses 

Baker Engineering and Risk Consultants, Inc. of San Antonio, Texas was contracted by the CSB 

to conduct a battery of analytical chemical and thermal reactivity tests on the chemicals involved 

in the TAC process. The test program results follow. 

1.0 Raw Materials Tests 

Samples of the cyanuric chloride and allyl alcohol from the same lots used by MFG Chemical on 

the day of the incident were obtained by the CSB and analyzed by Baker using combined gas 

chromatography and mass spectroscopy (GC/MS) and then compared against pure materials 

obtained from Sigma-Aldrich. The chromatograms of the samples originating from MFG 

Chemicals were indistinguishable from chromatograms of the pure materials obtained from 

Sigma-Aldrich. These tests confirmed that the runaway reaction was not the result of any 

contamination present in the raw materials. 

2.0 Thermal Stability Studies 

Thermo-chemical testing focused on the desired and undesired reactions encountered during the 

incident. Bench top, adiabatic, and reaction calorimetry were used to obtain data to assist in 

understanding the nature and extent of the allyl alcohol / cyanuric chloride runaway reaction. 

2.1 Bench Top Experiments 

Bench-top experiments qualitatively assessed the nature and extent of the reaction that results, 

under varying conditions, from mixing the reactants. Three experiments were run to understand 
 Appendices April 2006 

87 

the effects of reactant order addition; the impact of the catalyst; and the need for agitation of the 

reaction mass. The mass ratios of allyl alcohol, cyanuric chloride, and catalyst corresponded to 

those used by MFG on April 12, 2004. Each experiment was performed without active cooling. 

A calorimeter recorded the temperature of the reaction mass as a function of time. 

The results of these bench top experiments clearly show that the reaction between these two 

reactants—at room temperature—is spontaneously exothermic (e.g., heat producing), regardless 

of the order of addition of reactants; the presence or absence of the catalyst; or whether agitated 

or not. No action was required to initiate the reaction other than to allow the allyl alcohol and 

cyanuric chloride to come in contact with each other. 

2.1.1 Adiabatic Calorimetry 

Adiabatic calorimetry provides data that enable the characterization of a runaway reaction in 

terms of the temperatures and pressures as a function of time developed under the near adiabatic 

conditions normally found in a closed reactor. Transforming these data into temperature and 

pressure rise data permits the determination of the size of the emergency relief device needed to 

protect the vessel in the event of a runaway reaction. The results are summarized in Table 1. 

The runaway chemical reaction incident in the TAC process involved two reactions: (1) the 

desired synthesis reaction to form the products; and (2) an undesired decomposition reaction. 

The heat produced by the undesired decomposition reaction, which began at the exotherm onset 

temperature, exceeded the heat removal capacity of the R4 reactor and rapidly raised the 

temperature of the batch (see maximum recorded rate of temperature rise). That heat generation 

caused the vapor pressure of the allyl alcohol to rise until it boiled and the reaction released 

additional gases, pressurizing the vessel (see maximum recorded rate of pressure rise). The heat 

release also raised the temperature inside the R4 reactor above the decomposition temperature 

(see maximum exotherm temperature), at which point gaseous products produced by the 
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88 

decomposition reaction resulted in even greater pressure (see maximum pressure during 

exotherm). This culminated in the blowout of the manway gasket, activation of the rupture disc, 

and final release of the material to the atmosphere. 

Table 1. TAC Recipe Adiabatic Calorimetry Results 

Property 

High 

Thermal 

Inertia b, f

Low 

Thermal 

Inertia 

Unvented

Low 

Thermal 

Inertia 

Vented e

Units 

Maximum exotherm temperature a

424 310 147 Degrees centigrade 

Maximum recorded rate of 

temperature rise a 

205 1050 2618 Degrees centigrade 

/ minute 

Maximum pressure during exotherm a

103 48 11 Bar-absolute 

Maximum Recorded Rate of Pressure 

Rise a 198 409 155 Bar-absolute 

/ minute 

Total Heat of Decomposition a, c, d > -388 > -252 > - 72 Calories / gram of 

reaction mass 

Notes: 

a: The calorimeter was shut down by the safety control system. The final temperature achieved during 

the runaway reaction would have been much higher than recorded. 

b: Test cell ruptured during final stages of runaway reaction 

c: Using heat capacities calculated to be 2.0 Joule / gram-°Kelvin for all reactants 

d: The exothermic decomposition heat is greater than this value – see Notes a and b 

e: Sample was vented to atmosphere at 75 psi (6 bar) so exotherm was not run to completion 

f: Thermal inertia represents the ability of a material to conduct and store heat.

The adiabatic calorimetry testing of the TAC recipe demonstrated the extremely energetic nature 

of the reaction. The test that simulated the rupture disc opening (Table 1- Low Thermal Inertia, 

Vented) showed that the reaction progressed very slowly for about 90 minutes, after which the 
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temperature rapidly increased at a rate exceeding 500 °F/minute (260 °C/minute) with a pressure 

rise rate approaching 2260 psi/min (155 bar/minute). The test data is presented in Figure 1. 

Figure 1. Test cell pressure and temperature for the low thermal inertia, vented at 6 barg (75psig) 

test. 

 

2.1.2 Evaluation of Emergency Relief Size for Reactor R4 

The test results from the low thermal inertia adiabatic calorimetry (see column 4, Table 1) were 

used to estimate the area of the emergency relief device required to protect the reactor against 

catastrophic failure in the event of a two-phase (e.g., vapor with entrained liquid) runaway 

reaction. The data generated by this type of calorimetry were used with the AIChE Design 

Institute of Emergency Relief Systems (DIERS) methodology to provide the required relief area. 
 Appendices April 2006 

90 

The calculations show that an ideal vent diameter of 16.1 inches is needed, at a rupture disc burst 

pressure of 75 psig allowing for a 10% overpressure as stipulated in the ASME Boiler and 

Pressure Vessel Code, Section VIII, Division 1. The R4 relief device diameter, at the time of the 

incident, was 4 inches. Experimentally, the successful venting of the test cell contents at 75 psig, 

without rupturing the test cell, confirms that a 17-inch vent diameter of was needed to 

successfully vent the reactor. To account for friction losses in the vent system, a friction loss 

factor is included as a safety margin. Including this factor of 0.62 as recommended by API 520, 

increases the estimated vent diameter to 20.5 inches. 

These experimental results lead to the following conclusions: 

• The rupture disc on R4 at the time of the release was inadequate to relieve the pressure 

within the reactor without exceeding the ASME code limits for overpressure protection. 

• The actual area of available venting on the reactor could not be accurately calculated 

because an additional vent paths developed before the rupture disc activated as the 

pressure rose inside the reactor. The pressure blew out the improperly installed manway 

gasket and material also vented up through the condenser and into another vessel. The 

rupture disc on that vessel also activated during the runaway reaction. 

2.1.3 Reaction Calorimetry 

Reaction calorimetry is used to study the desired reaction. Information obtained from this type of 

study includes the reaction heat at the study temperature, the instantaneous peak power, and the 

total energy output of the reactor. The latter quantity may be used to estimate the cooling 

requirements of the reactor. The results of these tests are shown in Table 2. 
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91 

Table 2. Allyl Alcohol / Cyanuric Chloride Mixture Reaction Calorimetry Results 

Property Result 

Total Energy 82 kJoule 

Q max -121.3 calories / gram cyanuric chloride 

Peak Power 6.5 watts 

The test results show that the total energy liberated by the reaction was 82 kJ, which corresponds 

to 121.3 cal g-1 of cyanuric chloride (22.4 kcal mol-1). In the experiment the peak power output 

occurred about 125 minutes after mixing the reactants, it was about 6.5 watts for the total charge 

of cyanuric chloride. 

2.1.4 Evaluation of Cooling Capacity for Reactor R4 

The rate of temperature rise inside the R4 reactor depended on the balance between the reaction 

rate, the heat capacity of the chemicals, and the heat removal by the reactor cooling jacket. The 

following equation governs heat flow in the reactor: 

Q = UA (TJ – TR) Equation 1 

Where: 

Q = energy of the reaction (watts) 

U = heat transfer coefficient of the system (watts/meter2

 ° Kelvin) 

A = reactor wetted surface area (meter2

) 

TR = temperature of the reactants (° Kelvin) 

TJ = temperature of the jacket (° Kelvin) 
 Appendices April 2006 

92 

As shown in equation 1, the amount of heat removed is directly proportional to the difference 

between the temperature of the reactants and the temperature of the jacket. 

However, the reaction rate is determined both by the volumetric concentrations of the two 

reactants and the temperature. The rate of reaction increases exponentially with temperature as 

shown in Equation 2. 

R = f(C1, C2...Cn, e

TR

) Equation 2 

Where: 

R = reaction rate 

C1, C2...Cn = volumetric concentration of reactants 

TR = temperature of the reactants (° Kelvin) 

Equations 1 and 2 are shown graphically in Figure 2. If the reaction temperature exceeds the 

value at point A, the rate of heat production by the reaction exceeds the rate of heat removal 

provided by the reactor cooling jacket and the reaction will run away. 

Figure 2. Heat Generation versus Heat Removal Rate 
 Appendices April 2006 

93 

At the beginning of the reaction, the reactants are at their maximum concentrations. As the 

reaction proceeds to completion, the starting materials are depleted and the reaction slows down. 

Therefore, at the start of the batch with a high inventory of reactants, the influence of temperature 

on the heat generation rate is greatest and there is the most danger of exceeding the heat removal 

capacity of the reactor and cooling system. 

After adding the full charge of allyl alcohol to the full charge of cyanuric chloride and catalyst 

inside the reactor, the only way to balance the heat removal rate with the heat generation rate was 

to manually adjust the flow of the cooling medium through the reactor’s jacket. Even if the 

cooling system had been adjustable on the MFG reactor, the ultimate limit on cooling capacity is 

highly dependent on the surface-to-volume ratio of the reactor. If the heat generated inside the 

reacting chemical mass cannot be transferred to the reactor wall, where the cooling system is 

connected, the chemical mass will heat up above the critical temperature and the reaction will run 

away regardless how much cooling capacity the chiller can provide to the reactor cooling jacket. 

Kriebitzsch and Klenk (2002) report that cyanuric chloride will decompose (e.g., undergo 

exothermal hydrolysis) during the manufacture of cyanurates from alcohols if the heat of reaction 

is not dissipated and the solution acidity is not neutralized. They also note that because this 

decomposition reaction liberates a large amount of heat [2164 KJ/kg (930 BTU/lb)], it can 

become uncontrollable and run away. The CSB calculated the required cooling capacity to be 

6.45 x 106

 BTU per batch based on the cyanuric chloride charge in the reactor. However, 

according to calculations performed by MFG, the required cooling capacity of the chiller was 

based on 56 kJ per mole of sodium hydroxide (612 BTU/lb of sodium hydroxide). This 

corresponded to a cooling capacity of only 2.88 x 106

 Btu per batch. 
 Appendices April 2006 

94 

2.1.5 Condenser Cooling Capacity 

In some batch operations, evaporation and condensation (refluxing) can be an effective heat 

removal technique. Heat generated by the reaction boils a solvent or other material in the reactor. 

A condenser cools the vaporized material and converts it back to liquid, thus transferring the heat 

to the water used to cool the condenser and removing it from the process. MFG did not consider 

the use of vaporization and condensation as a heat removal mechanism even though the reactor 

was fitted with a condenser. Some vaporization and condensation of the allyl alcohol did occur in 

the batch, but the rate of vaporization proceeded too fast for all the materials to condense in the 

condenser. Non-condensable gases (e.g., carbon monoxide) were also being generated which 

reduced the condenser cooling capacity. 

3.0 Runaway Reaction Decomposition Products 

Analysis 

Gas and vapor samples collected from two runaway reactions—carried out under conditions 

mimicking those of the incident in a calorimeter—were analyzed by GC/MS. The major 

compounds vented during these tests were allyl alcohol, allyl chloride, carbon monoxide, and a 

C12 unsaturated compound derived from allyl alcohol or allyl chloride that could not be positively 

identified. Neither the chromatograms, nor the mass spectrometer data of the runaway reaction 

products showed evidence of cyanuric chloride, or its degradation products, such as cyanogen 

chloride, or hydrogen chloride. 

A sample taken from inside the R4 reactor was analyzed both visually and chemically. The 

material consisted mostly of a white solid interspersed with a small amount of granular black 

material (Figure 3). The black material could be elemental carbon arising from a high temperature 

event, such as a thermal runaway, or auto-ignition of allyl alcohol during the final stages of the 

runaway reaction. Auto-ignition of the allyl alcohol was possible because the maximum 
 Appendices April 2006 

95 

temperature reached during the lab experiments of the allyl alcohol/cyanuric chloride runaway 

reaction was 425 °C, which exceeds the reported auto-ignition temperature of allyl alcohol (375 – 

378 °C). Chemical analysis of the sample, by GC/MS, was not successful due to insolubility of 

the material. 

Figure 3. Residue removed from the reactor after the runaway reaction. 
 Appendices April 2006 

96 

Appendix B 

Plume Modeling Results 
 Appendices April 2006 

97 

Appendix B 

Plume Modeling Results 

Air quality dispersion modeling is a tool used to predict potential offsite consequences of 

accidental chemicals releases. A dispersion model uses a set of mathematical equations to 

simulate the release and dispersion of a chemical into the atmosphere. The model is typically 

computer based and integrates information about chemical properties, atmospheric conditions, 

and terrain features to estimate the vulnerable population and sensitive environmental area(s) 

affected by the release. 

The "hazard zone" is the geographical area affected by the release, which is typically displayed 

graphically on a local map. The "endpoint" is the outer boundary of the hazard zone. For 

flammable materials, the endpoint represents a blast wave capable of breaking glass (e.g., 

pressure equal to one psig), or radiant heat intense enough to blister human skin. If the material is 

toxic, the endpoint is based on a concentration -- referred to as a public exposure guideline -- 

considered hazardous to the affected community. Most people can be exposed to a toxic endpoint 

concentration for a certain duration (ranging from ten minutes to eight hours) without suffering 

irreversible health effects or other symptoms that would make it difficult to escape from the vapor 

cloud. 

There are several possible sources of uncertainty in a dispersion model. For example, the toxic 

chemical mass released and the release duration are usually only rough estimates. Wind speed 

and direction might be based on measurements that are far from the vapor plume. In addition, the 

random variations in the plume concentration cannot be accurately modeled. Given these 

limitations, even the best dispersion model concentration estimates generally have uncertainties 
 Appendices April 2006 

98 

of a factor of two. Emergency management personnel need to consider this when using 

dispersion modeling information either for planning or during an actual emergency. 

Baker Engineering and Risk Consulting was contracted by CSB to model the MFG incident timedependent discharge rates (i.e., blow down) from the reactor and the reaction products dispersion 

to evaluate the likely impact on the surrounding community. The analyses used two validated 

computer dispersion models: SafeSite3GTM developed by BakerRisk and STRAPP developed by 

NIST. 

1.0 Dispersion Model Input Parameters 

Air dispersion models require input data from three main categories: land use and terrain 

information; meteorological conditions; and source/emission parameters. The MFG vapor cloud 

release model input data is summarized below. 

1.1 Land Use and Terrain Information 

The rate at which a vapor plume disperses and reaches ground level is affected by the degree of 

urbanization of the surrounding area. The MFG plant is located in a relatively flat, forested 

terrain in a semi-rural area southeast of downtown Dalton, GA. The surface roughness of this 

geographical area was judged to be 50 mm, using a rough correlation by Pasquill (1974) for the 

category “few trees in summer.” 

1.2 Meteorological Conditions 

Wind direction and speed, ambient temperature, mixing (discharge) height, and atmospheric 

stability are typical inputs used to simulate vapor plume transport and dispersion. The model 

used weather data collected by the National Climatic Data Center of the National Oceanic and 

Atmospheric Administration at the Dalton regional airport on the day of the incident Because 
 Appendices April 2006 

99 

the release occurred after sunset at approximately 9:30 PM and with calm wind conditions, a 

slightly stable atmosphere (Pasquill-Gifford class E) was chosen. 

1.3 Source/emission parameters 

The source/emission parameters define how the hazardous materials were released to the 

atmosphere. The MFG Chemical, runaway reaction on April 12, 2004 resulted in a release of 

both allyl alcohol and allyl chloride vapors into the community (See Appendix A). There were 

two discharge points involved in the release: a leaking gasket on an 18-inch diameter reactor 

manway on top the reactor, followed about a minute later by discharge through a 4-inch diameter 

vent line after the reactor rupture disc blew. The manway leak area was estimated to be about 

1/8-inch wide along half of the circumference, about 28 inches. 

The calorimetry testing (see Appendix A) demonstrated that the actual reaction that occurred 

inside the reactor was substantially different from the expected reaction. Reaction mass, vapor, 

and enthalpy balances were calculated using the dominant molar stoichiometry from the 

calorimetric tests to find the fraction of cyanuric chloride reacted when the reactor pressure 

exceeded the rupture disc setpoint—this was computed to be 56%. 

Next, the SafeSite3GTM and STRAPP models were used to develop a flash curve (Figure 1) for 

the initial conditions of the release. Two different models were required because the vapor liquid 

equilibrium properties of allyl alcohol and allyl chloride are distinctly non-ideal. The STRAPP 

model was used to determine the initial two-phase discharge rate using non-ideal vapor/liquid 

equilibrium correlations while the SafeSite3GTM model was used to predict the blowdown and 

dispersion. 
 Appendices April 2006 

100 

56% Conversion

0

0.05

0.1

0.15

0.2

0.25

0.3

0.35

15 35 55 75 95

Pressure, psia

Mass fr Vapor

80

100

120

140

160

180

Temp, deg C

xv-STRAPP xv-DIP T, STRAPP Tsat-DIP

Figure 1. Flash Curves by STRAPP and DIPPR Properties 

2.0 Air Dispersion Model Results 

The models predict that the duration of two-phase flow (i.e., vapor and liquid discharge) was 70 

seconds followed by a long vapor discharge (106 minutes before reactor pressure decayed to 

atmospheric. The manway gasket discharge was predicted to totally evaporate without rainout.1

 

The tank conditions at the time of discharge were taken at a pressure just below the 75 psig 

rupture disc setpoint. The initial manway discharge was estimated to have occurred 133 seconds 

before the rupture disc blew. The manway discharge continued for the duration of the release. 

 

1

 Rainout is fallout by liquid; in this case, the released vapors may condense in the atmosphere and form 

droplets that will then fall as liquid. 
 Appendices April 2006 

101 

The rupture disc vent pipe discharge was directed downward, close to the ground. The model 

predicted the total duration of 208 minutes during which 58 mass percent will form a liquid pool 

in the diked concrete area.2

 This pool constantly expanded, but did not reach the dike walls 

before all of the liquid evaporated. Although the evaporation rate dropped off with time, the 

model predicted that 93% of the material discharged from the rupture disc either directly flashed, 

or evaporated from the pool into the atmosphere within the first 17 minutes of the release. In 

comparison, this was about the same elapsed time from the start of the release to the fire 

department arrival at the facility and initiation of the water fog spray to begin knocking down the 

vapors being released from the reactor and the liquid pool in the dike. 

2.1 Dispersion Model Endpoint Concentrations 

As both allyl alcohol and allyl chloride are flammable and toxic, the endpoint concentrations 

were determined for both cases. 

2.2 Flammable Endpoint 

The upper and lower flammable limits for the mixture released from the reactor were calculated 

using LeChatelier’s rule. Figure B-2 is the side-view plot of the vapor cloud rupture disc release 

concentration limits. The flammable concentration profiles used a 15-second averaging time, 

essentially the instantaneous concentration in the plume. The model predicted that the flammable 

range occurred between 50 and 180 meters (164 and 591 feet) from the release (shaded area in 

Figure 2). 

 

2

 The model excluded the effects of the large volume of water added by the fire department. 
 Appendices April 2006 

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Figure 2. Plume Side View Plot of Rupture Disc Release 

2.3 RMP Flammable Endpoint 

The EPA Risk Management Program endpoint for a flammable liquid is the distance from the 

release where the explosion overpressure has attenuated to one psig. The overpressure is 

calculated using the TNT equivalence method with 10% explosion efficiency. The flammable 

endpoint was calculated to be 391 meters (1,283 feet) using the released mixture heat of 

combustion. Considering the location of the reactor in the MFG facility, if the released 

flammable material had ignited, explosion and/or fire damage would likely have been limited to 

the MFG facility with minor explosion overpressure damage (e.g., broken windows, damaged 

siding) to adjoining industrial properties on the east and west sides of the MFG property. 

2.4 Toxic Endpoint 

Public exposure guidelines are used as the basis for a toxic endpoint even though few have been 

developed. Public exposure guidelines are generally meant to protect all segments of the 

population, including the very young and the very old, pregnant women, and hypersensitive 

individuals. 
 Appendices April 2006 

103 

2.4.1 Public Exposure Guidelines for the Released Materials 

The American Industrial Hygiene Association (AIHA) has developed and published 

approximately 110 Emergency Response Planning Guidelines (ERPGs). They are used to 

anticipate human adverse effects caused by exposure to toxic chemicals. The ERPGs are threetiered guidelines that use a one-hour contact duration: 

ERPG-1 - general irritation or clearly defined objectionable odor, 

ERPG-2 - experiencing or developing irreversible or other serious health effects or 

symptoms that could impair escape, 

ERPG-3 - life-threatening health effects. 

The ERPG guidelines do not protect everyone. Hypersensitive individuals are likely to suffer 

adverse reactions to concentrations far below those suggested in the guidelines. 

ERPGs have been developed for allyl chloride (Table 1), one of the main components released 

from the reactor at MFG Chemical: 

Table 1. Allyl Chloride ERPG Values 

ERPG-1 ERPG-2 ERPG-3 

Allyl Chloride 3 ppm 40 ppm 300 ppm 

The National Research Council’s Committee on Toxicology is developing Acute Exposure 

Guideline Levels (AEGL) that include guidelines for sensitive individuals. The goal of the 

committee is to develop 400 to 500 high priority, acutely hazardous substance levels by the year 

2010. As of late 2005, more than 160 substances have been evaluated. The AEGL guidelines 
 Appendices April 2006 

104 

consider five exposure durations: ten minutes, thirty minutes, one hour, four hours, and eight 

hours in each of three tiers. The AEGL tiers are the same as the EPRG tiers listed above. Interim 

AEGLs have been developed for allyl alcohol (Table 2), the primary component released during 

the MFG incident. 

Table 2. Allyl Alcohol Interim AEGL Values (ppm) 

Guideline Exposure time (minutes) 

(Tier) 10 30 60 240 480 

AEGL-1 2.1 2.1 2.1 2.1 2.1 

AEGL-2 4.2 4.2 4.2 4.2 4.2 

AEGL-3 130 130 67 17 8.3 

It is important to evaluate toxic endpoints using the proper exposure duration – preferably 

adjusting them to the actual exposure duration. The analysis applied the toxic endpoints to a 

common basis equal to 15-minute exposure as a molar average on a reciprocal basis. To obtain 

ERPG values for 15-minute exposures, the 60-minute ERPG exposure was multiplied by 2.0 as 

recommended by Brown, et al. , (2005). As the AEGL values are constant between 10 and 30-

minute exposures, they were used for 15-minute exposures. Table 3 lists the toxic endpoint 

concentration values adjusted for a 15-minute exposure for each guideline group. The values in 

the last row represent weighted average contours using the ERPGs for allyl chloride and the 

AEGLs for allyl alcohol. 
 Appendices April 2006 

105 

Table 3. Toxic Endpoint Values Adjusted For Dispersion Plumes (ppm) 

Component ERPG-1 (15 min.) ERPG-2 (15 min.) ERPG-3 (15 min) 

Allyl Chloride 6 80 600 

AEGL-1 (15 min.) AEGL-2 (15 min.) AEGL-3 (15 min.) 

Allyl Alcohol 2.1 4.2 130 

Average Contour 

Value 

3.4 9.3 238 

2.4.2 Toxic Endpoint Results 

Figure 3 shows the hazard zones for the weighted average contour values for the rupture disc vent 

release. The stars indicate locations where people exposed to the toxic vapor made calls to the 

Dalton 911 call center. 

Figure 4 shows the hazard zones for the weighted average contour values for the manway gasket 

release. Although the manway discharge is a weaker source and the predicted dispersion is low, 

the small puff extends a considerable distance due to the low wind speed (approximately one 

meter/second) during the release. However, in dispersion prediction uncertainty increases as 

wind speeds decrease below about three meters/second. 
 Appendices April 2006 

106 

Figure 3. Predicted hazard zones for the rupture disc release. 

. 

Figure 4. Predicted hazard zones for the manway gasket release. 

Green - ERPG/AEGL 1 

Blue - ERPG/AEGL 2 

Red - ERPG/AEGL 3

Green (dashed) - ERPG/AEGL 1 

Blue (dotted) - ERPG/AEGL 2 

Red (solid) - ERPG/AEGL 3 
 Appendices April 2006 

107 

2.4.3 Affected Population 

Information from the U.S. Census Bureau for Whitfield County, GA from the 2000 census was 

used to determine the population affected by these hazard zones. The estimated population 

affected by the rupture disc release was 1,533 people in the ERPG/AEGL 2 hazard zone, and 

1,656 people in the ERPG/AEGL 1 hazard zone. The estimated population affected the manway 

gasket release was 305 people in the ERPG/AEGL 2 hazard zone, and 574 people in the 

ERPG/AEGL 1 hazard zone. The combined estimated population affected by both release points 

was 1059 - 1656 people in the ERPG/AEGL 1 hazard zone, and 687 - 1007 people in the 

ERPG/AEGL 2 hazard zone. 

2.4.4 RMP Toxic Endpoint 

The EPA Risk Management Program regulates allyl alcohol as a toxic liquid, but does not 

regulate allyl chloride. The allyl alcohol toxic endpoint for a 60-minute exposure is 0.036 mg/l. 

The dispersion distance to the toxic endpoint is a function of the pool evaporation rate. The 

calculated evaporation rate was 85.4 pounds per minute based on the EPA formula for an undiked 

pool. The time required to evaporate all of the allyl alcohol in the pool was 74 minutes. The 

predicted distance to the toxic endpoint was 3.38 miles based on the EPA formula for a rural 

terrain. This is in good agreement with the maximum distances predicted by the dispersion model 

for the manway gasket leak plume (3.16 miles) and the rupture disc plume (2.84 miles) as shown 

in Figures 3 and 4. 
 Appendices April 2006 

108 

Appendix C 

Logic Tree 
 Appendices 
 Appendices 
 Appendices 
 Appendices 
 Appendices