MEC4427 Assignment 1

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T2 Laboratories Explosion Report
Group Number 3
Hansen Lim 21528136
Chun Ho Mah 21799814
Wai Hoe Loke 21979936
Ainsley Ng 22103627
Ken Yoong Fong 21640556
MEC4427 System Integrity and Maintenance

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Table of Contents
Summary.................................................................................................................................................3
1.0 Introduction ................................................................................................................................4
2.0 Failure Analysis ...........................................................................................................................5
2.1 Sequence of events.................................................................................................................6
2.2 Failure Modes and Effects (Criticality) Analysis (FMECA) and Fault Tree Analysis (FTA)........6
2.3 Root cause of failure...............................................................................................................8
2.4 Theory behind physical failure mechanism ..........................................................................10
2.4.1 Explosion by fast fracture .............................................................................................10
2.4.2 Micromechanisms of fast fracture................................................................................11
3.0 Consequences...........................................................................................................................12
4.0 Recommendation......................................................................................................................15
5.0 Significance of event.................................................................................................................16
5.1 Comparison with similar events............................................................................................16
5.2 Learning.................................................................................................................................17
Conclusions ...........................................................................................................................................18
References ............................................................................................................................................19

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Summary
On 19 December 2007, a powerful explosion equivalent to 1400 pounds of TNT and a massive fire
occurred in Jacksonville, Florida at T2 laboratories. This report titled “T2 Laboratories Explosion”
describes the sequence of events, consequences and the root causes of the disaster in detail. T2
Laboratories Inc. is a chemical processing facility that specialized in the design and manufacture of
chemicals for gasoline additives. It began full scale production of methylcyclopentadienyl
manganese tricarbonyl (MCMT) in 2004 and continued producing MCMT until its 175th batch in
2007 when the disaster happened.
The impact of explosion travelled across 1900 feet away from T2 laboratories and thus causing
damages to its surrounding environment. 16 business premises were surveyed in this report and
found that buildings located approximately 600 ft. away from T2 laboratories suffer irreparable
damages. Moreover, structures such as rail road and Faye road were also damaged due to debris of
explosion. 167 employees from different business premises were present at the time of incident
with 32 of them sustained minor injuries while four T2 employees succumbed to their death due to
close proximity with the reactor. Hence, this explosion had brought about both physical and human
consequences.
The root cause of the runaway reaction was identified to be due to lack of knowledge of a second
and more energetic exothermic reaction during the design of the MCMT production line. Because of
the ignorance, there were no redundancies in the design of the reactor, which has led to an
inefficient water cooling system and an ineffective pressure relief system. The failure of the water
cooling system has triggered the runaway reaction and the excessive temperature and pressure
generated from the reaction caused the reactor to explode.
The reactor explosion can be explained by the fast fracture failure mechanism. As pressure increase
within the reactor, the total elastic energy increases. When this reaches a critical limit where the
internal perforations of the wall become unstable and grow instantaneously, the energy of the
system will be released abruptly, causing a massive explosion. Therefore, when designing high
pressure reactors, it is very important to take note of the critical stress of the system and implement
appropriate stress relief measures.
In order to prevent future incident, recommendations are made. The most important part is to do
OH&S checks on working place. OH&S is essential for employer to prevent potential incident from
occurring and to be able to response to emergency situations. The next important thing is the
knowledge on hazard; therefore hazard education is important for each tester/employee. Finally,
chemical testings are to prevent the improper balancing on scaling up after lab test.

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1.0 Introduction
T2 Laboratories Inc. is a chemical processing facility that specialized in the design and manufacture
of chemicals primarily for gasoline additives. It is a small privately owned chemical manufacturing
plant located in the largest city in the state of Florida, Jacksonville that began operations in 1996. A
chemical engineer and a chemist founded T2 as a solvent blending business. From 1996 to 2001, T2
operated from a warehouse located in a mixed-used industrial and residential area in downtown
Jacksonville. In 2001, T2 expanded their business by leasing a 5 acre site in north of Jacksonville to
construct a MCMT process line. In January 2004, T2 began full scale production of MCMT and by
December 2007, MCMT production was the primary business operation (T2 Laboratories Inc.
Runaway Reaction 2009).
Since 1947 MCMT has been commonly used as a supplement to increase the octane rating in fuels. It
is also used as a lubricant to prevent automotive engine valve seat recession. However, this fuel
additive is a combustible liquid and is very toxic by inhalation or skin contact. Both the National
Institute for Occupational Safety and Health (NIOSH) and Occupational Safety and Health
Administration (OSHA) set exposure limits for MCMT whereas the Environment Protection Agency
(EPA) designates MCMT as extremely hazardous substances despite its quick decomposition
characteristics under exposure to sunlight (T2 Laboratories Inc. Runaway Reaction 2009).
The MCMT plant consists of extensive pipe networks which include the coolant line, product line,
heating line and the drainage line. However, primary reactions occur in the jacketed chemical batch
reactor which is considered one of the main components in the MCMT process line. A chemical
batch reactor is widely used in the process industries for a variety of process operations such as
solids dissolution, product mixing, chemical reactions, batch distillation etc. A typical batch reactor
consists of a tank with an agitator and integral cooling system or heating system (Batch Reactors
n.d.).
The production of MCMT could be simplified into three steps which are the metalation step,
substitution step and finally the carbonylation step. The first step in the MCMT manufacturing
process involves reaction of liquid chemicals with sodium metals in the chemical batch reactor
(metalation process). The reactants are heated to a temperature of 3000
F while being mixed with an
agitator. This exothermic reaction releases heat energy into the batch reactor and at the same time
produces hydrogen gas as a by-product which is vented into the atmosphere. In normal operational
conditions, the temperature of the reactants is allowed to rise to 3600
F before the operator initiates
the cooling system. The coolant used in this system is domestic water which is pumped through the
cooling lines into the jacket of the batch reactor. When the coolant boils, it will absorb the heat and
then be released as steam into the atmosphere. The cooling system is controlled by an operator
using a computerised control system to maintain the batch reactor below 3600
F (T2 Laboratories Inc.
On December 19, 2007, T2 laboratories were producing its 175th batch of methylcyclopentadienyl
manganese tricarbonyl (MCMT) in the 2500 gallon chemical batch reactor. At 1.23pm, the process
operator directed an outside operator to call the two owners, who were off site to report a cooling
problem and request they return. The operator initiated the cooling system at 3600
F to cool the

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reactor as usual however the cooling system appears to be ineffective. At this point, the
temperature and pressure inside the batch reactor continued to rise uncontrollably.
A few minutes after the call, the two owners returned to the manufacturing plant. While one of the
owners searched for the plant mechanic, the other went to the control room to assist the operator.
The owner in the control room was concerned about a possible fire, he warned employees to move
away from the reactor.
The pressure inside the batch reactor caused the rupture disc in the pressure relief system to burst
at 400lbs/in2
as designed. However, the pressure inside the batch reactor continued rising exceeding
600psig, which is the maximum allowable working pressure of the batch reactor. At about 1.33pm,
the batch reactor gave into the pressure and erupted. The blast was heard from miles away and the
plant continued to burn in flames as the explosion destroyed assets in surrounding factories. The
blast damaged buildings about 1500ft away causing debris to be flown up to 1 mile away.
Unfortunately, 4 people were killed in this blast including the co-owner of the company.
Furthermore, 32 people were injured and taken to the hospital. The blast is said to have an impact
equivalent to 1400 pounds of TNT explosives.
The U.S. Chemical Safety and Hazard Investigation Board (CSB) carried out extensive investigations
and identified the root cause as T2 not recognizing the runaway reaction hazard associated with the
MCMT it was producing. A chemical runaway reaction refers to a situation where an increase in
temperature changes the conditions in a way that causes a further increase in temperature, often
leading to a destructive result (HSE 2007). The reaction consists of a second undesired exothermic
reaction that started at a higher temperature. During the 5th
batch of MCMT production, drastic
increase in temperature was observed but was ignored. Even worse, the owners intentionally
increased the batch size by one-third when customer requests increased.
Other contributing causes of the disaster are that the cooling system employed by T2 was
susceptible to single-point failures due to lack of design redundancy. The designers did not include
back-up cooling systems in case of a breakdown. Furthermore, the workers and owners at T2 did not
practice preventive maintenance on the process plant. This is proven on at least one occasion in
2006, the reactor drain valve had failed during operations and required repair.
In addition, the MCMT reactor pressure relief system was incapable of relieving the pressure from a
runway reaction. The CSB determined that it is unlikely for the pressure relief system set at 400Psig
to release the pressure in time once the second exothermic reaction started. However, if T2 had set
the pressure release valve to rupture at 75Psig, the disaster would have been avoided completely.
A combination of design errors and negligence has resulted in the loss of human lives. Furthermore,
this incident led to financial, environmental and legal consequences.
This report starts with failure analysis, which includes Fault tree analysis(FTA) and Failure Mode and
Effects Analysis (FMEA), followed by the theory behind the explosion disaster. Next, the report
outlines the consequences of the disaster, which includes the physical damages on the surrounding
environment and the casualties involved. The report also discusses the lessons learnt from this
incident and the recommendations to avoid future similar disasters.

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2.0 Failure Analysis
2.1 Sequence of events
Date and Time Personnel Event
December 18, 2007
Evening Night shift operator Prepared reactor for new MCMT batch
December 19, 2007
7:30 am Day shift operator Began manufacturing process for Batch 175
from control room
11:00 am Day shift operator Batch heated to initiate chemical reaction
Monitored the temperature and pressure
1:23 pm Day shift operator Noticed cooling problem
Asked outside operator to call owners
1:26 pm Day shift operator,
Owner/chemical engineer
Diagnose problem in control room
Owner/chemist Searched for plant mechanic
1:29 pm Owner/chemical engineer Went to the reactor and mentioned employees
to get away
1:31 pm Owner/chemical engineer Returned to control room
1:33 pm Reactor’s pressure relief system cannot control
runaway reaction
Eyewitnesses Saw venting from the reactor and heard loud
sound then the reactor exploded
Table 1: Sequence of events
2.2 Failure Modes and Effects (Criticality) Analysis (FMECA) and Fault Tree Analysis (FTA)
Component or
activity
Failure Mode Severity of
Failure (C)
Frequency (F) Mitigation (M) Risk Measure
(CFM)
Water supply
valve or water
drain valve
Fails to open
or close
Insufficient
coolant flow
rate into the
reactor jacket,
C = 8
0.3 per year,
F = 6.5
Flow of
coolant
through a
bypass valve,
M = 1
52
Pneumatic
system
Does not work
or react
Valve does not
operate
causing no
coolant flow,
C = 9
0.3 per year,
F= 6.5
No regular
preventive
maintenance,
M = 8
468
Water supply
piping
Blockage due
to mineral
scale built up
Insufficient
cooling
causing
pressure built
up in reactor,
C = 10
0.1 per year,
F = 6
Low
probability
avoidance of
mineral scale
build up,
M = 9
540
Temperature
indicator
Faulty
Incorrect
temperature
reading of the
reactor,
C = 9
0.01 per year,
F = 5
No backup
temperature
reader,
M = 10
450
Table 2: FMECA of T2 Explosion

Page | 7Figure 1: FTA of T2 explosion

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2.3 Root cause of failure
According to the incident analysis conducted by the U.S. Chemical Safety and Hazard Investigation
Board (CSB), there were six possible causes for the runaway reaction to occur. These six causes were:
i. Cross-contamination of the reactor
ii. Contamination of raw materials
iii. Wrong concentration of raw materials
iv. Local concentration of chemical within the reactor
v. Application of excessive heat
vi. Unidentified chemical reaction
While scenarios (i) to (v) could be the culprit behind the runaway reaction, they were determined to
be highly unlikely to have happened (T2 Laboratories Inc. Runaway Reaction 2009).
In an interview with the T2 owner/chemist, he mentioned that cross-contamination of the reactor
had previously occurred and the only consequences were low yields or batch polymerisation. The
possibility of contamination of raw materials was similarly ruled out as the raw materials used on the
day of the incident came from the same shipments that had been used in previous successful
batches.
Based on the reaction chemistry, the accelerated reaction rate that caused the runaway reaction
could only have occurred if there was an increase in the amount of sodium loaded into the reactor.
Since sodium was hand-loaded by operators in fixed batches, wrong concentration of raw materials
was unlikely. On the other hand, varying local concentration within the reactor would reduce rather
than accelerate reaction rate because maximum reaction rate can only be achieved with uniform
distribution of raw materials.
In the case of heat application, hot oil system was used and calculations have shown that the cooling
system had the capacity of 10 times greater than the maximum capacity of the hot oil system (T2
Laboratories Inc. Runaway Reaction 2009). If the heating had continued beyond 300o
F (148.9o
C), the
cooling system would have removed the excess heat easily.
With most of the scenarios being ruled out, the only credible scenario to have caused the incident
was lack of knowledge in a chemical reaction previously unidentified when designing the MCMT
production line. According to the results of the laboratory testing conducted on the batch recipe
used by T2 on the day of the incident, the standard T2 chemical recipe, without sufficient cooling,
would trigger a second and more energetic exothermic reaction when the temperature exceeded
390o
F (198.9o
C) (T2 Laboratories Inc. Runaway Reaction 2009). This second exothermic reaction was
capable of producing extreme temperature and pressure. However, the T2 owner/chemist reported
that he have no knowledge on the second exothermic reaction as the laboratory testing that he had
conducted never exceeded 380o
F (193o
C). Since the owner/chemist did not investigate the reaction’s
behaviour at higher temperatures, he did not observe evidence of exothermic runaway potential,
thus allowing the second exothermic reaction to occur and caused the reactor explosion on
December 19, 2007.
Insufficient cooling, as reported by the process operator stating that there was a cooling problem
shortly before the explosion, had contributed to the triggering of the runaway chemical reaction.

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When investigators looked into the design of the reactor, as shown in Figure 2 below, they found out
that the cooling water system lacked design redundancy, making it susceptible to single-point
failures including
 Failures of water supply valve or water drain valve
 Failure of the pneumatic system that was used to operate the water valves
 Blockage or partial blockage in the water supply piping
 Faulty temperature indication
 Mineral scale build-up in the cooling system
Figure 2: Possible failure components of the reactor and ductile tearing of perforations in material (Image
Courtesy of T2 Laboratories Inc. Runaway Reaction 2009)
As mentioned, without sufficient cooling, the T2 chemical recipe was capable of producing extreme
temperature and pressure. Therefore, failure in any of the components in the water cooling system
would have caused the heat removal cycle to malfunction. Formation of mineral scale inside the
cooling jacket could also interfere with the heat removal capacity of the cooling water system as
loose scale could have blocked the water piping. All of these would have enabled the temperature
and pressure to build up in the reactor and finally caused the violent reactor failure to occur.

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Unfortunately, T2 took no initiative to contain this hazard as interviews with employees have shown
that T2 would usually ran cooling system components to failure and did not perform routine
preventive maintenance. There were even occasions since 2006 where the reactor cooling drain
valve had failed during operations and required repair. Subsequently, there was also no backup
water supply to provide cooling water should the main water supply be cut off due to unforeseen
circumstances. Although a control system malfunction or operator error might also have led to the
insufficient reactor cooling problem, there was no evidence to indicate that either of these have
occurred.
Another contributing cause to the reactor explosion was the ineffective pressure relief system. T2
sized the pressure relief devices at 400psig, which was based on anticipated normal operations,
namely the maximum expected hydrogen gas generation during normal operation, without
considering potential emergency conditions. If T2 had set the pressure relief devices to 75psig, the
runaway reaction would have been relieved during the first exothermic reaction, preventing the
triggering of the second exothermic reaction.
2.4 Theory behind physical failure mechanism
As mentioned in the previous subsection, due to ineffective cooling and pressure relief system, the
temperature and pressure build-up in the reactor ultimately lead to a catastrophic explosion. The
failure mechanism of the explosion is most likely overloading, or more specifically failure by fast
fracture, which is the instantaneous growth of existing perforations in the material as they abruptly
become unstable.
2.4.1 Explosion by fast fracture
In this context, as the pressure in the reactor escalate dramatically due to the chemical reaction, the
total amount of elastic energy in the system increases. As the pressure eventually build-up to the
critical pressure for fast fracture, the existing perforations in the material that made up the reactor
walls will become unstable and grow suddenly, causing explosion (Ashby & Jones 2002). Therefore, it
is of utmost importance that all pressure vessel designers take into account the critical stress of the
system.
The critical stress of a system can be derived from a simple energy balance equation. As shown in
the equation below, for fast fracture to occur, the work done by loads must be more than the
change in elastic energy and the energy absorbed at the crack tip, where is the toughness of the
material. The toughness for steels range from 10kJm-2
to 103
kJm-2
(Ashby & Jones 2002).
where = Work done by external loads
= Change in elastic energy
= Thickness of material
= Change in crack/flaw size

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From the above relationship, and by considering a fixed displacement fast fracture, the fast fracture
condition for engineering structures can be obtained.
√
where = Fracture toughness, √
= Stress subjected/critical stress
= Crack/flaw size
= Numerical correction factor
In the context of T2 lab reactor explosion, an estimation of the material perforation size, , and the
fracture toughness, , should be readily available from the reactor designer. Since the existing
flaws of the reactor must be microscopically small, the numerical correction factor, , can be
assumed to be 1. Finally, based on the equation shown above, the critical stress, , can then be
easily calculated. The maximum allowable pressure for the system can then be worked out from this
value. In the accident, because the pressure exceeded this critical value, it caused an explosion.
2.4.2 Micromechanisms of fast fracture
Before fast fracture occurs, the internal cracks or perforations start to propagate due to stress
localisation around the crack tip. At these stress concentrated areas, the localised stresses will reach
the yield stress of the material quicker than the average stress applied. As shown in the equation
below, the closer it is to the crack tip, the higher the stress. This also make the crack behaves as if it
is longer, where this effective crack tip in the plastic region is known as the notional crack tip
(Janssen, Zuidema & Wanhill 2004).
( )
where = Distance from the crack tip
When the material starts to tear at these areas, plastic flow occurs around the small inclusions of
chemical compounds that are commonly present in most metals. The crack will grow due to the
coalescence of voids in the plastic region near the crack tip. This mechanism is known as the ductile
tearing and can be illustrated in the Figure 2 above (Ashby & Jones 2002).
In most general situations, the plastic flow near the crack tip will turn the originally sharp tip into a
blunt tip, thus reducing the stress concentration and eventually stopping the crack propagation
(Ashby & Jones 2002). In the T2 laboratory accident, the pressure and stress involved are so great
that it is enough to create instantaneous crack propagation, leading to a rapid release of the stored
energy of the whole system, causing a massive explosion.

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3.0 Consequences
Due to the massive explosion with magnitude that sums up to approximately 1400lb of
Trinitrotoluene (TNT) (T2 Laboratories Explosion Damage Assessment 2010), its damages impact
manage to extends up to 1900 feet surrounding the T2 laboratories (T2 Laboratories Inc. Runaway
Reaction 2009).
Figure 3: Map of T2 laboratories and its surrounding within 1900ft (Image courtesy of T2 Laboratories
Explosion Damage Assessment 2010)
Analysis on the damages was conducted in this project and can be categorised into physical, human
and financial damages. Damages on buildings and structures are part of the physical consequences
caused by the explosion. ABS has conducted a qualitative observation that surveys all buildings
involved in the explosion by using two types of approaches known as the Explosive Risk and
Structural Damage Assessment Code (ERASDAC) and SDOF Blast Effect Design Spreadsheet (SBEDS)
(T2 Laboratories Explosion Damage Assessment 2010). Both approaches describe buildings damages
Faye Road
Rail Road
T2 LaboratoriesWall Street Trailers

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level as given in table 3 and 4 respectively. Table 5 summarizes the result of damages level on some
of buildings surrounding T2 laboratories using both approaches.
Building Damages Level Damage Description
1 Onset of visible damage to reflected wall of building.
2A Reflected wall components sustain permanent damage requiring
replacement, other walls and roof have visible damage that is generally
repairable.
2B Reflected wall components are collapsed or very severely damaged. Other
walls and roof have permanent damage requiring replacement.
C Reflected wall has collapsed. Other walls and roof have substantial plastic
deformation that may be approaching incipient collapse.
D Complete failure of the building roof and substantial area of walls.
Table 3: Damage level description using ERASDAC
Building Damage Level Damage Description
Superficial No permanent deformations. The facility is immediately operable.
Repairable Space in and around damaged area can be used and is fully functional
after clean-ups and repairs.
Unrepairable Progressive collapse will not occur. Space in and around the damaged
area is unusable.
Heavy Onset of structural collapse. Progressive collapse is unlikely. Space in and
around damaged area is unusable.
Severe Progressive collapse likely. Space in and around damaged area is
unusable.
Table 4: Damage level description using SBEDS
Buildings
Distance from T2
(feet)
Damage Level
ERASDAC SBEDS
Stover Sales 970 1 Superficial
Prezine 570 2A Unrepairable
MastHead 550 2A Unrepairable
PBM Construction 720 2A Repairable
Refractory Repair Service 1005 2A Repairable
Wall Street Trailers 250 2B Heavy
Tri – State Contractors 300 3 Heavy
Cogburn Brothers 895 2A Repairable
Wilkinson Steel 660 1 Superficial
School Bus Depot 1467 1 Superficial
Maccurrah Golf Construction 880 2A Repairable
Personal Residence (Trailer) 1040 1 Superficial
Unknown name 1450 1 Superficial
Truck Lease Services 1660 1 Superficial
Arlington Heavy Hauling 833 2A Some Unrepairable
Petticoat Construction Company 1447 1 Superficial
Table 5: Summary of some buildings damaged level

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As a result of this explosion, other businesses surrounding T2 have been greatly affected. For
example, Wall Street Trailers, a trucking company which had trailer as their office located 250ft away
from T2 laboratories, was completely destroyed by the explosion suffering heavy damages as shown
in Figure 3. Fortunately, no employees were present during the time of incident. Besides that,
structures such as a rail road were pushed out of place caused by the impact of collision with a
2000lb section of the 3 inch thick reactor head (Figure 3). A 4 inch diameter agitator shaft from the
reactor had caused crack damage on Faye Road situated 350 ft. away from T2 (Figure 3). All these
were caused by force of the blast that propels debris from T2 to all directions (T2 Laboratories Inc.
A total of 36 victims from T2 laboratories and its surrounding businesses were involved in this
disastrous incident. Unfortunately, four T2 employees were killed instantly by the explosion due to
their very close standoff distance from the reactor during the time of incident. Meanwhile, there are
five other T2 employees (one of them is a truck driver that delivers mineral spirit to T2) that escaped
the fatality of the explosion with only one critically injured while the rest attained minor injuries. The
remaining 28 victims are employees from businesses surrounding T2 laboratories as those listed in
Figure 4. Injuries reported from these employees were either lacerations or contusions, hearing loss,
or thrown by the force of the explosion blast that travelled 1900 feet wide (T2 Laboratories Inc.
Runaway Reaction 2009). Figure 4 present a summary of injury statistics of victims from T2
laboratories and its surrounding businesses; there were a total of 167 employees from different
businesses present during the time of incident.
Figure 4: T2 Laboratories Explosion Injury Statistics
As seen from the consequences from this incident, an explosion in a chemical plant is highly
dangerous as its impact could travel a wide distance affecting also the surrounding environment; this
may bring about a large death and injury tolls. Moreover, it could also lead to daily operation failure
of other businesses which may lead to financial losses in a company. Therefore, precaution steps and
0
5
10
15
20
25
30
Numberofemployees
Business Name
Death
Minor injuries
No injuries

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safety work operation should always be prioritised and practiced in a chemical plant that produces
explosive chemical.
4.0 Recommendation
The T2 Laboratories explosion occurred due to many failures of components that had led to fatal
catastrophe. In this section recommendations are made in order to prevent such event to take place
in the future.
a) Chemical Testing
One of the reasons that these incidents occur is due to underestimation of the T2 employee.
It is stated that MCMT production has little references that can be relied on hence
laboratory testing is required. However T2 had only done test on 1 litre scale of reactor and
since the test run smoothly, the tester did not perform full scale analysis on the full scale
reactor. Cooling requirements in one litre test did not indicate the correct amount coolant
required for full scale reactor to prevent exothermic reaction to occur. Hence it is
recommended to perform a full scale analysis before proceeding in production of first batch
of MCMT, as stated in Designing and Operating Safe chemical Reaction Processes (HSE 2000),
it is important to properly scale-up design process equipment and the potential for incidents
to occur in full scale processes that have appeared uneventful in testing.
b) Process Hazard Analysis
In chemical reaction process it is required to perform Process hazard analysis. It is done in
order to establish operating limits and identify operating strategies to prevent run away
reactions. Analysis on reactor systems can help to determine the potential process
deviations and equipment malfunctions, including agitator failure, loss of cooling,
contamination and mischarging feed stocks, all of which are common causes for runaway
reactions. One of process hazard analysis that can be performed is Hazard and operability
study (HAZOP) during the scale-up. By doing HAZOP it is likely to identify the Nature of
reaction and the limitations of the cooling and pressure relief systems.
c) Hazard education
The knowledge of understanding the hazard reactivity and process safety education is
important. Therefore it is highly recommended that all engineering degree include this
education inside the curriculum of the study. With this knowledge engineers will understand
how important to perform runaway reaction testing, address emergency relief, and identify
as well as evaluate the cause the process upsets. This will help to reduce the possibility of
the incidents to occur.
d) Occupational Health & safety
It is requirement in workplace that OH & S implemented by the employer, it is to create a
management program to prevent or to minimize the consequences of catastrophic releases
of hazardous chemicals. Some of the key elements in OH&S are conducting Process hazard
analysis, implementing and maintaining written operating procedures, set up periodic
operator training, and executing a management change program.
It is also required to do risk management planning to understand the chemicals that pose
significant hazards to surroundings if accidental releases occur. In risk management planning

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report, it is required to include the response on emergency situation including worst case
and alternative release scenarios, as well as the plan to improve safety.
5.0 Significance of event
5.1 Comparison with similar events
T2 laboratories explosion was not the only disaster that occurred due to the failure of chemical
reactor. There were comparably similar events that occur in industries and plants all around the
world. In this section, similar incidents to T2 explosion will be stated and briefly discussed.
a) Morton International Inc. (April 8,1998)
This disaster has occurred In Paterson, New Jersey, The incident caused fire and explosion as
the consequences of runaway reaction. Nine employees were injured. It also caused the
release of chemicals into the community and damage to the plant (HSE 2007).
The runaway reaction was caused by the yellow 96 reaction, which accelerated beyond the
heat removal capability of the reactor; it causes a secondary runaway decomposition
reaction, causing an explosion that blew up the reactor hatch and released the reactor
contents. The initial runaway reaction is due to incapability of the cooling system of
controlling the exothermic reaction and there are no emergency shutdown program
installed.
The cooling failure is due to the inadequacy of Morton Inc. to evaluate and control the
Yellow 96 production process.
b) Concept Sciences Inc. (February 19, 1999)
Concept Sciences Inc. facility that has vessel containing hundreds of pounds of
hydroxylamine explodes. This explosion occurred near Allentown, Pennsylvania. The facility
was making the first batch of hydroxylamine; during the distillation process the piping and
the process tank decomposed, this was most likely due to high temperature and high
concentration. The disaster killed four employees and the manager of the adjacent business.
Four other people near the building were injured. The explosion also caused significant
damage to other buildings.
The company has developed the hydroxylamine through laboratory test, and set up the full
production facility in July 1998. The production parameters involved a high concentration of
hydroxylamine which could cause exothermic decomposition, forming explosive crystal. The
company did not evaluate the reactive hazards of the process during the production
development phase, determine the scale of the hazard, nor identify the control measures.
c) MFG Chemical Inc. (April 12, 2004)
MFG was producing its first batch of triallyl cyanurate (TAC). However, a runaway reaction
occurred and over pressurized the chemical reactor at the MFG plant. This incident caused
the release of toxic allyl alcohol to the environment. The toxic cloud hospitalised 154 people,
killed nearby vegetation and aquatic life.
It was later found out that MFG had not carefully researched the reactive hazards of the
process before scaling up from lab test to full scale production. The reaction test done by

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MFG was designed to maximize yield and minimize production cause without involving
additional exothermic reaction into consideration, this reaction require extra cooling. MFG
had underestimated the removal capacity between the test batch and the full scale
production (HSE 2007).
d) Synthron (January 31, 2006)
In Morganton, North Carolina a disaster of vapour cloud explosion and fires killed one
worker, injured 14 people, and damaged structures in the nearby community. The source of
this explosion takes place in Synthron facility. This facility manufactured varieties of powder
coating and paint additives, the process done by polymerizing acrylic monomers in a reactor.
The background of the explosion is due to increase of order of slightly more additive than
the normal size recipe produced; hence the plan managers scale up the recipes to meet the
requirement. This caused more than doubled the rate of energy release in the reactor,
exceeding the cooling capacity of the reactor condenser, which led to runaway reaction. The
reactor over pressurised, solvent vapours vented from the reactor’s manway, flammable
cloud form inside the building and hence the vapour found the ignition source hence it
explodes.
Main cause of this catastrophe is due to failure of identifying the hazards associated with
this type of chemistry, additionally the process safety documentation is poorly arranged, the
recipes changed without further analysis, the safeguards to prevent the runaway reaction
does not exist.
5.2 Learning
There are several lessons that can be learnt from this tragedy. Most of the incidents background is
due to underestimation and carelessness of the employee in preparing the full scale reaction.
Firstly the chemical testing should have been done properly; it is crucial, before the start of doing
any process design, to investigate further the effect of scaling in process system reactor.
Underestimation of the effect of scaling must be avoided in the future. The chemical reaction may
act in different manner than the laboratory testing hence scaling effect investigation is crucial.
The other main concern that should have taken into account is the knowledge of hazard information
and analysis. This section need to be emphasized to the employer hence all the employee will
understand and be more responsible on the part that they are assigned and assured about the safety
of the process they are doing. Understanding the hazard will help the employee to perform analysis
on each of the dangerous process they are assigned to and hence reducing the potential of the
damage and able to take response on the emergency situation.
Finally it is needed to apply OH&S in workplace especially where dangerous chemical is involved. It is
compulsory for employer to make sure the safety of its employee and by applying the OH&S this can
be achieved.

Page | 18
Conclusions
The 1400 pounds of TNT equivalent explosion at T2 laboratories on December 19, 2007 is considered
U.S.’s most severe industrial accident in nearly five years. The massive explosion and fire killed four
people, while leaving 28 people injured. The cause of the explosion was due to a system cooling
failure that presents insufficient cooling of the chemical batch reactor. Insufficient cooling of the
batch reactor caused an unwanted second exothermic reaction to occur causing high temperature
and pressure build up in the reactor which led to the explosion.
The failure of the cooling system was due to several reasons including blockages in pipes due to
mineral deposition, valve failure or pneumatic failure. However, the cooling system in the T2
laboratories process plant was not designed with redundancy. If a backup cooling system were to be
installed, the disaster could be avoided completely. Furthermore, staffs at T2 laboratories were not
train to perform preventive maintenance, and components in the process plant are allowed to
function until failure.
To prevent disasters such as this to occur again, national regulatory bodies which controls industrial
operations sectors should recommend more stringent rules for process plant designs. Chemical
testings should be carried out to ensure all possible reactions be recorded to account for them in the
design stage. In addition, process Hazard analysis of the entire process should be carried out to
ensure any possible hazards are eliminated or controlled. Furthermore, employers are responsible
for instilling good operation health and safety habits to create a safe working culture amongst
employees. In any industry, safety should be made the highest priority. A culture of preventive
maintenance should be practiced and employees and employers alike should solve any maintenance
issue despite the cost.

Page | 19
References
Ashby, M.F. & Jones, D.R.H. 2002, Engineering Materials 1: An Introduction to their Properties and
Applications, 2nd edn, Butterworth-Heinemann, Great Britain.
Janssen, M., Zuidema, J. & Wanhill, R. 2004, Fracture Mechanics, 2nd edn, Spon Press, Oxfordshire.
T2 Laboratories Inc. Runaway Reaction 2009, US Chemical Safety and Hazard Investigation Board,
Washington DC.
T2 Laboratories Explosion Damage Assessment 2010, ABS Consulting, San Antonio.
Health and Safety Executive (HSE) 2007, Health and Safety Executive, Sudbury, Suffolk, viewed 28
August 2012, <http://www.hse.gov.uk/pubns/indg254.htm>
Batch Reactors n.d., University of Michigan, Michigan, viewed 27 August 2012,
<http://www.engin.umich.edu/~cre/asyLearn/bits/batch/index.htm>

MEC4427 Assignment 1

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MEC4427 Assignment 1