Incidents Map

A major fire broke out on a refinery processing unit designed to convert heavy oil residues into refined products, resulting in serious damage to the plant. [ Property Damage $250 Million. Estimated Current Value $259 Million ]

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Image credit: ENI

An explosion and fire that occurred in a polyethylene wax processing facility operated by Marcus Oil and Chemical on the southwest side of Houston, Texas. On Friday, December 3, 2004, at about 5:50 pm, employees heard a loud “pop” then saw light from a fire reflecting off a shiny tanker truck parked near the process equipment. About 45 seconds later, a violent explosion occurred and a fire fueled by molten wax erupted near the main warehouse. The warehouse and nearby equipment were quickly involved in the fire.

The Houston Fire Department arrived approximately five minutes after the explosion. Firefighters extinguished the three-alarm blaze by midnight, approximately seven hours after the explosion.

Three firefighters were slightly injured while fighting the fire, and local residents sustained minor injuries from flying glass. The explosion shattered windows in buildings and vehicles and caused structural damage as far as one-quarter mile away. Significant interior damage resulted when suspended ceilings and light fixtures were blown down in the onsite buildings, nearby businesses, and a church. Tank 7, a 12-foot diameter, 50-foot long, 50,000-pound pressure vessel was propelled 150 feet where it impacted a warehouse belonging to another business..

KEY ISSUES:
• PRESSURE VESSEL REPAIRS & ALTERATIONS
• NITROGEN INERTING SYSTEM DESIGN & OPERATION

ROOT CAUSES:
1. Poor welding severely weakened Tank 7 and led to its catastrophic failure.
2. The connection between the nitrogen and the compressed air systems increased the oxygen concentration in the inerting gas to an unsafe level.
3. Pressure vessels had operating pressures in excess of 100 psig, yet none was equipped with a pressure relief device.

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Image Credit: CSB

In the early hours of 3 December 1984 a relief valve on a storage tank containing highly toxic methyl isocyanate (MIC) lifted. A cloud of MIC gas was released which drifted onto nearby housing.

Prior to this, at 23.00 hrs on 2 December, an operator noticed the pressure inside the storage tank to be higher than normal but not outside the working pressure of the tank. At the same time a MIC leak was reported near the vent gas scrubber (VGS). At 00.15hrs a MIC release in the process area was reported. The pressure inside the storage tank was rising rapidly so the operator went outside to the tank. Rumbling sounds were heard from the tank and a screeching noise from the safety valve. Radiated heat could also be felt from the tank.
Attempts were made to switch on the VGS but this was not in operational mode.

Approximately 2,000 people died within a short period and tens of thousands were injured, overwhelming the emergency services. This was further compounded by the fact that the hospitals were unaware as to which gas was involved or what its effects were. The exact numbers of dead and injured are uncertain, as people have continued to die of the effects over a period of years.

The severity of this accident makes it the worst recorded within the chemical industry.

KEY ISSUES:
• PLANT MODIFICATION / CHANGE PROCEDURES
• REACTION / PRODUCT TESTING
• DESIGN CODES – PLANT
• MAINTENANCE PROCEDURES
• EMERGENCY RESPONSE / SPILL CONTROL

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The Halifax Explosion was a maritime disaster in Halifax, Nova Scotia, Canada, which happened on the morning of 6 December 1917. The Norwegian vessel SS Imo collided with SS Mont-Blanc, a French cargo ship laden with high explosives, in the Narrows, a strait connecting the upper Halifax Harbour to Bedford Basin, causing a large explosion on the French freighter, devastating the Richmond district of Halifax.

Approximately 2,000 people were killed by the blast, debris, fires or collapsed buildings, and an estimated 9,000 others were injured. The blast was the largest man-made explosion at the time, releasing the equivalent energy of roughly 2.9 kilotons of TNT (12,000 GJ).

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Image Credit: Library of Congress

The International Biosynthetics (IBIS) plant was, at the time of the accident, a wholly owned subsidiary of Shell UK Ltd. and employed some 250 people in the manufacture of fine chemicals.

The release occurred on the phosgene plant at 11:27 hours on 7 December 1991. The batch reaction involved the phosgenation of dimethyl aniline (DMA) in a toluene solution. The process involved the addition of 1 tonne of recycled toluene to the reactor, then as no more recycled toluene was available fresh toluene was to be added. Attempts were made to fill the reactor with 2 tonnes of fresh toluene. The flow indicator showed that the required amount of toluene had been added to the reactor, however a control valve between the pump and the vessel was closed and none of the toluene had been added. A level measurement was available for the vessel but as the process appeared to be proceeding normally this was not checked.

The next stage was to add 20 kg of phosgene to check if any water was present in the reactor. This would have resulted in a temperature rise of the solution. Because there was insufficient toluene in the vessel, the temperature indicator was not in the solution and therefore showed no temperature rise. As there appeared to be no water in the reactor, 0.8 tonnes of phosgene were then added to the vessel. After a shift changeover the next steps in the process were carried out. These were to add 1.6 tonnes of DMA and heat to 65°C. The operating temperature was reached but the temperature continued to rise to well above 100°C. As the pressure increased the pressure control valve, pressure relief valve and bursting disc all operated as designed and relieved the vessel to a scrubbing column. The reaction was more violent than had been predicted and the relief system had insufficient capacity to deal with the pressure rise. This resulted in a connection on the condenser line failing and releasing the contents of the vessel to atmosphere. Fortunately the phosgene had been consumed in the reaction. However, the vapour cloud drifted for 4 km affecting about 60 people and staining some property blue.

KEY ISSUES:
• CONTROL SYSTEMS
• REACTION / PRODUCT TESTING
• RELIEF SYSTEMS / VENT SYSTEMS

Report: https://www.icheme.org/media/13702/release-of-chemicals-from-international-biosynthetics-ltd.pdf

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Image Credit: HSE

On December 7, 2009, at approximately 2:30 pm, State Special Vessel No. 2, under an operating pressure of 29,000 psig, suddenly and violently ruptured, 120 days into a 150-day operating cycle. A white cloud of steam and debris rapidly expanded outward from the facility, traveled onto the interstate, and dissipated within seconds.

The sudden release of superheated liquid caused an eight-foot tall by four-foot wide vessel fragment, weighing approximately 8,600 pounds, to travel through two concrete walls and finally land about 435 feet from the NDK building. The fragment skipped across a neighboring facility parking lot and slammed into the wall of an adjacent business office. The force of the impact pushed the wall inward causing furniture to shift and ceiling tiles to fall. One person working near the wall was injured.

The thrust from the escaping liquid caused the base of the vessel to violently shear away from its foundation and blew pieces of structural steel out of the building into the parking lot of a nearby rest stop gas station, known as the Illinois Tollway (I-90) Oasis. One piece of structural steel struck and killed a truck driver at the rest stop. After shearing from its base and throwing shrapnel out of the facility, the vessel swung from the building and landed on the ground outside.

KEY ISSUES:
• PRESSURE VESSEL DESIGN & MATERIAL SELECTION REQUIREMENTS
• LEARNING FROM PREVIOUS INCIDENTS
• INSPECTIONS

ROOT CAUSES:
1. Stress corrosion cracking.
2. Testing & inspection deficiencies.

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Image credit: CSB

An explosion ripped through the New Cumberland A.L. Solutions titanium plant in West Virginia on December 9, 2010, fatally injuring three workers. The workers were processing titanium powder, which is highly flammable, at the time of the explosion.

KEY ISSUES:
• FEDERAL COMBUSTIBLE DUST OVERSIGHT
• HAZARD RECOGNITION & TRAINING
• LEARNING FROM PREVIOUS INCIDENTS

ROOT CAUSES:
1. AL Solutions did not mitigate the hazards of metal dust explosions through engineering controls, such as a dust collection system. Specifically, AL Solutions did not adhere to the practices recommended in NFPA 484 for controlling combustible metal dust hazards.

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Image credit: CSB

A release of hexane created a vapor cloud which was ignited on an electric motor, causing an explosion. This resulted in damage to a process unit and injured 20 people. The plant was eventually replaced.

[ Property Damage $200 Million. Estimated Current Value $280 Million ]

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Image credit: Gaulke

In the early hours of Sunday 11th December 2005, a number of explosions occurred at Buncefield Oil Storage Depot, Hemel Hempstead, Hertfordshire. At least one of the initial explosions was of massive proportions and there was a large fire, which engulfed a high proportion of the site.

Over 40 people were injured; fortunately there were no fatalities. Significant damage occurred to both commercial and residential properties in the vicinity and a large area around the site was evacuated on emergency service advice. The fire burned for several days, destroying most of the site and emitting large clouds of black smoke into the atmosphere.

KEY ISSUES:
• SYSTEMATIC ASSESSMENT OF SAFETY INTEGRITY LEVEL REQUIREMENTS
• PROTECTING AGAINST LOSS OF PRIMARY CONTAINMENT
• ENGINEERING AGAINST ESCALATION OF LOSS OF PRIMARY CONTAINMENT
• ENGINEERING AGAINST THE LOSS OF SECONDARY AND TERTIARY CONTAINMENT
• OPERATING WITH HIGH RELIABILITY ORGANISATIONS
• DELIVERING HIGH PERFORMANCE THROUGH CULTURE AND LEADERSHIP

HSE Reports:
MIIB Final Report Vol 1: https://www.icheme.org/media/13707/buncefield-miib-final-report-volume-1.pdf
MIIB Final Report Vol 2a: https://www.icheme.org/media/13923/buncefield-miib-final-report-volume-2a.pdf
MIIB Final Report Vol 3a: https://www.icheme.org/media/13923/buncefield-miib-final-report-volume-2a.pdf
Land Use Planning – Recommendations: https://www.icheme.org/media/10694/recommendations-on-land-use-planning.pdf
Land Use Planning – Model: https://www.icheme.org/media/13709/illustrative-model-of-a-risk-based-lup-system_repaired.pdf
Explosion Mechanism: https://www.icheme.org/media/10696/buncefield-explosion-mechanism-advisory-group-report.pdf
BSTG Final Report: https://www.icheme.org/media/10697/safety-and-environmental-standards-for-fuel-storage-sites.pdf
Emergency Preparedness: https://www.icheme.org/media/10698/recommendations-on-emergency-preparedness.pdf
Design & Operation: https://www.icheme.org/media/10699/recommendations-on-the-design-and-operation-of-fuel-storage-sites.pdf
Initial Report: https://www.icheme.org/media/10700/buncefield-initial-report.pdf
Investigation – Progress Report: https://www.icheme.org/media/10705/buncefield-first-progress-report.pdf
Investigation – 2nd Progress Report: https://www.icheme.org/media/10703/buncefield-second-progress-report.pdf
Investigation – 3rd Progress Report: https://www.icheme.org/media/10702/buncefield-third-progress-report.pdf
Why did it happen?: https://www.icheme.org/media/10706/buncefield-report.pdf

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Image Credit: Hertfordshire County Council

At approximately 2:00 pm on December 11, 2002, a maintenance employee entered the wastewater treatment (WWT) room at Environmental Enterprises, Inc. (EEI), in Cincinnati, Ohio, to retrieve a tool. His path brought him directly alongside the WWT clarifier, an open-top tank with a conical bottom for settling solids (Figure 1).

As the mechanic approached the clarifier, he noticed a “rotten egg” odor that became stronger as he moved forward. He suddenly felt pressure in his lungs and was unable to breathe. He attempted to flee the area but was overcome by hydrogen sulfide (H2S) gas and collapsed.

Fortunately, fellow employees found the victim a few moments later and pulled him to safety. He recovered, and there were no other injuries. .

KEY ISSUES:
• HAZARD COMMUNICATION
• OPERATING PROCEDURES
• MANAGEMENT OVERSIGHT
• MECHANICAL INTEGRITY

ROOT CAUSES:
1. The facility had no written procedures for operating the WWT area.
2. The operator responsible for the WWT area had no formal training in waste treatment or chemistry.
3. This incident may have been avoided if the operator had been aware of the possible reactions that can produce H2S gas.
4. EEI did not have a formal system for investigating incidents and communicating findings to employees.
5. The facility did not implement procedures or assign responsibilities for calibrating, inspecting, and maintaining the H2S detector.
6. Management oversight could have ensured that then proper treatment methods were used.

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Image Credit: CSB

A straight run of eight-inch-diameter line carrying hot oil from the high pressure separator to the low pressure stripper in a refinery hydrodesulfurizer fractured circumferentially in the parent metal in the heat zone about 1.5 inches from a weld. Hot oil at 700 psi and 650°F sprayed across the roadway into the hydrogen units where ignition occurred. An intense fire around the pipe rack in the hydrogen plant caused a 16-inch-diameter gas line to rupture, adding a second blow torch to the fire. More pipes ruptured with explosive force in adjacent areas. The fire resulted in a crash shutdown of the entire 600,000 bbl/d refinery. After six and a half hours, the fire was extinguished. Damage was extensive. The three hydrogen plants and the four hydrodesulphurization (HDS) units were heavily damaged or destroyed. Before the loss, the line which failed was judged as having excessive vibration. It is believed that the hot oil line failed due to fatigue, considered, in turn, to be largely due to hydrogen embrittlement.

[ Property Damage $75 Million. Estimated Current Value $180 Million ]

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Image credit: PDVSA

An explosion occurred in the ammonium nitrate process area of this plant. As a result of the explosion, the seven-story main process building was completely destroyed and a 30-foot-diameter crater was created. Metal fragments from the explosion punctured one of the plant’s two 15,000-metric-ton refrigerated ammonia storage tanks. The punctured tank released an estimated 5,700 metric tons of ammonia, causing the evacuation of approximately 2,500 people from the surrounding area. Metal fragments also punctured a nitric acid tank, resulting in the release of approximately 100 metric tons of this acid. The explosion tore metal siding from adjacent buildings, damaged three third-party electric generating stations, broke windows of buildings 16 miles away in Sioux City, and was felt more than 30 miles away.

[ Property Damage $203 Million. Estimated Current Value $404 Million ]

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Image credit: EPA
Ref: https://en.wikipedia.org/wiki/Port_Neal_fertilizer_plant_explosion

On 14 December 1984 fire broke out in a furniture repository in Sheffield which formed part of a very large warehouse and transit shed building occupied by the National Freight Consortium plc. In two days the fire destroyed the whole warehouse, with the exception of one protection section. It involved the attendance of several hundred fireman over a total period of six days.

Among the wide variety of goods stored in the building was a relatively small tonnage of chemicals. Concern was expressed during and after the fire about the difficulty experienced by the Fire Brigade in identifying the possible risks from the materials stored, followed by allegations by the Fire Brigades’ Union that firemen had been unnecessarily exposed to harmful fumes without the benefit of breathing apparatus.

The fire also led to expressions of concern about a number of aspects, including the delay in summoning the Fire Brigade and possible exposure of member of the public to harmful fumes and asbestos material evolved in the fire.

Report: https://www.icheme.org/media/13698/the-brightside-lane-warehouse-fire.pdf

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Image Credit: HSE

A huge boil-over occurred on a fuel oil tank, killing at least 160 people in a huge fire ball. The explosion occurred on the fuel oil tank while it was being gauged, blowing the roof off the tank and setting it on fire. Eight hours after the tank fire started a violent boil-over occurred. Burning oil flowed down the hill where the tank was located and surrounded a second tank.

[ Property Damage $70 Million. Estimated Current Value $193 Million ]

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At 1:33 pm on December 19, 2007, a powerful explosion and subsequent chemical fire killed four employees and destroyed T2 Laboratories, Inc. (T2), a chemical manufacturer in Jacksonville, Florida. It injured 32, including four employees and 28 members of the public who were working in surrounding businesses. Debris from the reactor was found up to one mile away, and the explosion damaged buildings within one quarter mile of the facility.

On December 19, T2 was producing its 175th batch of methylcyclopentadienyl manganese tricarbonyl (MCMT). At 1:23 pm, the process operator had an outside operator call the owners to report a cooling problem and request they return to the site. Upon their return, one of the two owners went to the control room to assist. A few minutes later, at 1:33 pm, the reactor burst and its contents exploded, killing the owner and process operator who were in the control room and two outside operators who were exiting the reactor area.

KEY ISSUES:
• REACTIVE HAZARD RECOGNITION
• HAZARD EDUCATION
• EMERGENCY PREPAREDNESS
• PROCESS DESIGN & SCALE-UP

ROOT CAUSES:
• T2 did not recognize the runaway reaction hazard associated with the MCMT it was producing.

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Image credit: CSB

The incident occurred as a two-train, ethylene cracker was being started up after its major six-year turnaround. A spanner was left in the pipework going to the medium pressure stage of a compressor. This resulted in the compressor tripping on high vibration. The trip caused an overpressure in the high pressure stage of the compressor and a loss of containment of hydrocarbon that was ignited.

[ Property Damage $250 Million. Estimated Current Value $273 Million ]

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Image credit: Petroineos

An eight-inch-diameter pipeline operating at approximately 700-pounds-per-square-inch ruptured, releasing a mix of ethane and propane. The record low temperature of 10°F for the region is believed to have contributed to the rupture. After a few minutes, the resulting release was ignited, causing a vapor cloud explosion. The explosion shattered windows up to six miles away and could be felt as far as 15 miles away. Seventeen additional pipelines, in a pipe rack containing 70 lines, were ruptured by the explosion.

The resulting fire involved two large storage tanks holding 3.6 million gallons of diesel, 12 small tanks containing a total of 882,000 gallons of lube oil, and two separator units. The explosion resulted in the partial loss of electricity, steam, and fire water for the refinery, since two power lines, two steam lines and a 12-inch diameter fire water line were located in this pipe rack. Upon the initial explosion, the lines for the dock fire pumps were damaged. Therefore, the water for fire fighting had to be supplied with the remaining plant fire pumps and municipal fire trucks taking draught from alternate sources. Approximately 48,000 gallons of aqueous film-forming foam (AFFF) concentrate, 200 fire brigade members, and 13 pumper units were used during the fire fighting effort, which was successful in extinguishing the fire approximately 14 hours after the initial explosion. Because of this incident, the refinery was completely shut down for three days and operated at reduced capacity for an additional three weeks.

[ Property Damage $69 Million. Estimated Current Value $155 Million ]

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Image credit: Sam Kittner

Failure of seabed components caused 210,000 metric tonnes of FSU to break free in bad weather. Three out of four latch plates fractured. About 210,000 bbl-per-day of crude was lost, equating to about 10% of UK production.

[ Property Damage $60 Million. Estimated Current Value $138 Million ]

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Image credit: ShipSpotting.com

An explosion and fire occurred at a gas-to-liquids (GTL) plant in Bintulu, Sarawak. The fire was brought under control on the next day. The plant was one of only two commercially successful GTL plants in the world at the time, with a capacity to produce 12,500 bbl-per-day of middle distillates and waxes from natural gas feedstocks. The explosion occurred in the air separation unit (ASU) which supplied oxygen for the production of synthesis gas feedstock. The investigation into the incident pointed to an initial combustion event in the ASU as the most probable cause. This combustion event is thought to have initiated explosive burning of the aluminium heat exchanger elements in the presence of liquid oxygen, such that the elements ruptured explosively. Twelve people were injured, none seriously, and the plant was shut down for several months for repairs.

[ Property Damage $275 Million. Estimated Current Value $510 Million ]

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Image credit: Shell

A benzoyl peroxide (BPO) explosion and fire that occurred at the Catalyst Systems, Inc., production facility in Gnadenhutten, Ohio. At 11:55 am on January 2, 2003, a vacuum dryer holding nearly 200 pounds of BPO exploded. Employees were drying granular 75 percent BPO to make 98 percent BPO when the material explosively decomposed. One employee was slightly injured, and the BPO processing building was significantly damaged.

KEY ISSUES:
• HAZARDS OF BENZOYL PEROXIDE
• REACTIVE CHEMICAL HAZARDS
• PROCESS SAFETY MANAGEMENT SYSTEMS

ROOT CAUSES:
1. Industry standards and guidance documents not reviewed and followed.
2. Good engineering practices to manage the hazards not implemented.

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Image Credit: CSB

A hydrogen leak on a reactor ignited causing a fire in the hydrocracking distillation unit 87, causing extensive damage to the main reactor. No fatalities were declared.

On 4 January 1977, a serious fire and explosion occurred at the Braehead Container Clearance Depot at Renfrew in Scotland.

The fire and explosion, which originated at a warehouse occupied by James Kelman Transport and Storage, completely wrecked that warehouse and the adjacent whisky bonded warehouse occupied by Clyde Container Services Ltd and also caused widespread window and roof damage to domestic, commercial, industrial and public property within a radius of a mile of the premises. The cost of the damage is estimated at some £6 000 000.

It was fortunate that, despite the extent of the damage, only twelve members of the public and one watchman were treated for shock and minor injuries. After investigation had eliminated one cause of fire after another it was discovered that it had accidently been started by three boys who had lit a fire to warm themselves at a den which they had made, during the New Year holiday, from cardboard cartons stacked beside the warehouse.

Subsequent experimental work tended to suggest that explosions of this nature and severity can be caused by the involvement of commercially pure sodium chlorate under the intense heat conditions of an industrial fire.

Report: https://www.icheme.org/media/13693/the-fire-and-explosion-at-braehead-container-depot-renfrew.pdf

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Image Credit: HSE

A fire broke out at the oil sands refinery in Upgrader 2, an area of the plant that converts bitumen into crude oil products. Approximately 250 people were evacuated from the plant, but no injuries were reported. The fire burned for nine hours before being extinguished. Witnesses reported two explosions minutes apart which sent a fireball six stories high into the air. The plant also suffered ice damage from water used to fight the fire as temperatures in the area fell below -35 C. On February 3, 2005, the company announced that a ruptured cycle line was the most likely cause of the fire. Oil production was reduced from 225,000 bbl-per-day to about 110,000 bbl-per-day for about nine months.

[ Property Damage $120 Million. Estimated Current Value $168 Million ]

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Image credit: Suncor

On 4th January 1966, an operation to drain off an aqueous layer from a propane storage sphere was attempted. Two valves were opened in series on the bottom of the sphere. When the operation was nearly complete, the upper valve was closed and then cracked open again. No flow came out of the cracked valve, so it was opened further. The blockage, assumed to be ice or hydrate, cleared and propane gushed out. The operator was unable to close the upper valve and by the time he attempted to close the lower valve this was also frozen open. The alarm was raised and traffic on the nearby motorway was stopped. The resulting vapour cloud is thought to have found its source of ignition from a car about 160 m away. The storage sphere was enveloped in a fierce fire and upon lifting of the relief valve a stream of escaping vapour was ignited.

The LPG tank farm where the sphere was located consisted of four 1200 m3 propane and four 2000 m3 butane spheres. The fire brigade arrived on site, but were not experienced in dealing in refinery fires, and it appears they did not attempt to cool the burning sphere. They concentrated their hoses on cooling the remaining spheres. About 90 minutes after the initial leakage, the sphere ruptured, killing the men nearby. A wave of liquid propane flowed over the compound wall and fragments of the ruptured sphere cut through the legs of the next sphere which toppled over. The relief valve on this tank began to emit liquid.

The fire killed 18 people and injured 81 others. Five of the storage spheres were destroyed.

KEY ISSUES:
• DESIGN CODES – PIPEWORK
• SECONDARY CONTAINMENT
• OPERATING PROCEDURES
• EMERGENCY RESPONSE / SPILL CONTROL
• DESIGN CODES – PLANT

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Image Credit: Fonds Georges Vermard

This incident occurred at an oil sands facility, specifically with minor explosions occurring in the froth treatment plant. Damage appeared to be mainly limited to electrical cables in the solvent recovery area. The cause of the fire appears to have been a hydrocarbon leak in piping. The plant’s emergency response team was assisted by the local fire brigade and the fire was extinguished in two hours. Only one minor injury was reported. The incident occurred eight days after the new facility began operating.

[ Property Damage $120 Million. Estimated Current Value $189 Million ]

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Image credit: Jason Woodhead

One worker died after hazardous chemical vapors released from an over-pressurized reactor burned his respiratory system. The worker charged chemicals inside a reactor vessel and a reaction started before he could close it.

OSHA’s proposed penalties total $87,780

Proximate causes:
• Inadequate management/supervision

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Source: A web-based collection and analysis of process safety incidents (https://www.sciencedirect.com/science/article/abs/pii/S0950423016302285)
Image Credit: Google Maps

An explosion occurred on this oil sands upgrader site north of Fort McMurray, Alberta. Five workers were injured in the blast, including one who received third-degree burns. A subsequent fire occurred at the top of one of the site’s four coke drums and burned for nearly four hours. As a result, two of the coke drums were disabled. Workers returned to normal shifts the following morning. The majority of the damage was sustained above the cutting deck and derrick infrastructure of the coke drum. At the time of the incident, the plant was operating on bypass conditions due to process upsets. An internal investigation team determined that the fire resulted from the opening of the top unheading valve on an active low-pressure coke drum. This allowed hot hydrocarbons to be released within the coker cutting deck building and was followed by ignition, leading to the explosion and fire. Exceptionally cold weather following the incident hampered efforts to gain access to the coker unit’s cutting deck, due to the deluge protection in this area. Firefighting in freezing conditions caused additional damage.

[ Property Damage $385 Million. Estimated Current Value $425 Million ]

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Image credit: CBC

An explosion severely injured a graduate student at Texas Tech University in Lubbock, Texas, in the chemistry department during the handling of a high-energy metal compound, which suddenly detonated. Texas Tech had entered into an agreement with Northeastern University, which holds a contract from the U.S. Department of Homeland Security to study the high-energy materials.

KEY ISSUES:
• LABORATORY SAFETY MANAGEMENT FOR PHYSICAL HAZARDS
• HAZARD EVALUATION OF EXPERIMENTAL WORK IN RESEARCH LABORATORIES
• ORGANIZATIONAL ACCOUNTABILITY & OVERSIGHT OF SAFETY

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Image & AcciMap Credit: CSB

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Image credit: CSB

On January 7, 1998, two explosions in rapid succession destroyed the Sierra Chemical Company Kean Canyon plant near Mustang, Nevada, killing four workers and injuring six others.

The Kean Canyon plant manufactured explosive boosters for the mining industry. When initiated by a blasting cap or detonation cord, boosters provide the added energy necessary to detonate less sensitive blasting agents or other high explosives. The boosters manufactured at the Kean Canyon plant consisted of a base mix and a second explosive mix, called Pentolite, both of which were poured into cardboard cylinders. The primary explosives used in the base mix were TNT (2,4,6-trinitrotoluene), PETN (pentaerythritol tetranitrate), and Comp-B, a mixture of TNT and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine). The Pentolite is a mix of TNT and PETN.

KEY ISSUES:
• PROCESS SAFETY MANAGEMENT
• WORKER TRAINING
• PROCESS HAZARD ANALYSIS
• LANGUAGE BARRIERS

ROOT CAUSES:
1. Process hazard analysis (PHA) conducted by the facility was inadequate.
2. Training programs for facility personnel were inadequate.
3. Written operating procedures were inadequate or not available to workers.
4. The facility was built with insufficient separation distances between different operations and the design and construction of buildings was inadequate.
5. There was no systematic safety inspection or auditing program.
6. The employee participation program was inadequate.

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Image Credit: CSB

An 11-year-old, 121,000-deadweight-ton tanker had completed unloading its first parcel of Arabian heavy crude when a small fire was noticed on deck. About 10 minutes later, fire spread to both sides of the ship. Later, a massive explosion occurred. The initiating event of the disaster was likely the buckling of the ship’s structure at deck level. Explosions in the ballast tanks and the breaking of the ship’s back followed. These events were produced by the conjunction of two separate factors: a seriously weakened hull due to inadequate maintenance and an excessive stress due to incorrect ballasting at the time of the disaster. In addition to the total loss of the ship, 1,130 feet of the concrete and steel jetty were damaged or destroyed.

[ Property Damage $70 Million. Estimated Current Value $248 Million ]

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Image credit: Irish Times

In a chemical plant that produces fertilizer, carbon dioxide and dry ice, a pipeline explosion occurred.

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Source: A web-based collection and analysis of process safety incidents (https://www.sciencedirect.com/science/article/abs/pii/S0950423016302285)
Image Credit: Creston News Advertiser

A hydrocarbon release occurred from a reactor vessel on a naphtha hydrotreater unit. The vessel operated at around 25 bar and 140 degrees C. The release of hot naphtha and hydrogen created a vapor cloud that ignited, leading to an explosion and fire. It is understood that the explosion caused further releases from other parts of the plant, including a nearby diesel hydrotreater, which contributed to the fire.

Eight on-site employees were injured, but there were no fatalities. Residents of a nearby town were evacuated as a precaution. Several hundred firefighters were reportedly deployed to control the fire.

Some refinery process units were extensively damaged as a result of the explosion and fire, as well as multiple office and maintenance buildings within the refinery site. Windows in a village at least 3km away were broken. The initial release of hydrocarbon was understood to have occurred as a result of a 1.5-meter crack that opened up in the reactor vessel. The root cause of the vessel failure is not yet fully understood.

On January 9, 2014, West Virginia Department of Environmental Protection (WVDEP) inspectors arrived at the Freedom Industries (Freedom) chemical storage and distribution facility in Charleston, West Virginia, in response to complaints from the public about a chemical odor. Upon arrival, WVDEP inspectors discovered a chemical leaking from tank 396, an aboveground storage tank (AST). The leaking tank contents were originally reported as crude methylcychohexanemethanol (MCHM), but 13 days later Freedom reported it was a mixture of Crude MCHM and polyglycol ethers (PPH, stripped) called Shurflot 944.5 The chemical mixture escaped tank 396 through two small holes on the tank floor and traveled down a descending bank into the adjacent Elk River. The holes were caused by pitting corrosion that initiated on the internal surface of the tank floor. The tank contents drained into the gravel and soil surrounding tank 396 and found multiple pathways into the river. The secondary containment or dike wall, originally designed to control leaks, had cracks and holes from disrepair that allowed the mixture, containing Crude MCHM and PPH, stripped, to escape the containment. The leak also found a pathway to the river through a subsurface culvert, located under adjacent ASTs.

After prompting by WVDEP, Freedom took action to stop the leak and prevent further contamination by deploying services to recover the spill and vacuum the remaining tank contents. However, nearly 11,000 gallons of a mixture containing Crude MCHM and PPH, stripped had already entered into the surrounding soil and Elk River. Once in the river, it flowed downstream to the intake of the West Virginia American Water (WVAW) water treatment facility, about 1.5 miles downriver from Freedom. WVAW’s water treatment and filtration methods were unable to treat and remove all of the chemical mixture in its water treatment process and as a result, it contaminated the drinking water within WVAW’s distribution system. That evening, WVAW issued a Do Not Use (DNU) order for 93,000 customer accounts (approximately 300,000 residents) across portions of nine counties.

KEY ISSUES:
• TANK INSPECTIONS & MAINTENANCE
• RISK COMMUNICATION
• PUBLIC WATER SYSTEMS SAFETY & RISK ASSESSMENT
• TOXICOLOGICAL INFORMATION

ROOT CAUSES:
1. Corrosion of primary containment
2. Deteriorated secondary containment

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Image credit: CSB

The entire refinery was shut down for three months after being struck by Hurricane Georges. The hurricane left the entire plant submerged under more than four feet of salt water from the Gulf of Mexico. Although the hurricane was only a Category 2 storm, its slow movement subjected the refinery to 17 hours of high wind and rain. The storm surge overtopped the dikes built to protect the refinery. In all, some 2,100 motors, 1,900 pumps, 8,000 instrument components, 280 turbines, and 200 miscellaneous machinery items required replacement or extensive rebuilding. Newer control buildings and electrical substations sustained little or no damage, as they had been built with their ground floors elevated approximately five feet above grade.

[ Property Damage $190 Million. Estimated Current Value $349 Million ]

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Image credit: Chevron

On 10 January 1985 an explosion destroyed the central section of a three-storey block of luxury flats in South London, killing eight of the residents. Preliminary investigations indicated a gas leak as a probable cause.

It was found that the explosion was caused by gas leaking into the building from a crack in the gas main, a 150mm (6 inch) diameter cast iron pipe buried at the rear of the building, which carried gas at low pressure. The crack was primarily due to loading on the pipe caused by differential settlement. The loading could not be evenly distributed along the pipe, as it was held rigidly near the point of failure by the concrete encasement of a drain, which acted as a fulcrum.

Report: https://www.icheme.org/media/13699/the-putney-explosion.pdf

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Image Credit: HSE

On Wednesday, January 11, 2006, three workers continued the roof removal. About 11:15 a.m., the lead mechanic and the third worker were cutting the metal roof directly above the methanol tank vent. Sparks, showering down from the cutting torch, ignited methanol vapors coming from the vent, creating a fireball on top of the tank. The fire flashed through a flame arrester on the vent, igniting methanol vapors and air inside the tank, causing a explosion inside the steel tank.

The explosion inside the methanol storage tank
• rounded the tank’s flat bottom, permanently deforming the tank and raising the side wall about onefoot;
• ripped the nuts from six bolts used to anchor the tank to a concrete foundation;
• blew the flame arrester off the tank vent pipe;
• blew a level sensor off a 4-inch flange on the tank top;
• separated two 1-inch pipes, valves, and an attached level switch from flanges on the side of the tank;
• separated a 4-inch tank outlet pipe from the tank outlet valve; and
• separated a 4-inch tank fill pipe near the top the tank.

Methanol discharged from the separated pipes ignited and burned, spreading the fire. Methanol also flowed into the containment around the tank and through a drain to the WWTP where it was diluted and harmlessly processed. The lead mechanic and the third worker were in the man-lift basket over the methanol tank when the ignition occurred. They were likely burned from the initial fireball and burning methanol vapors discharging from the tank vent under pressure from the explosion. The lead mechanic, fully engulfed in fire, likely jumped or fell from the man-lift. Emergency responders found his body within the concrete containment next to the tank.

The third worker stated that he had been partially out of the man-lift basket leaning over the roof when the fire ignited. On fire, he climbed onto the roof to escape. Co-workers, unable to reach him with a ladder, told him to jump to an adjacent lower roof and then to the ground. He sustained second and third degree burns over most of his body, and was hospitalized for 4 months before being released to a medical rehabilitation facility. Methanol sprayed from separated pipes onto the crane, burning the crane cab with the mechanic inside. On fire, he exited the cab and was assisted by co-workers. He died in the hospital the following day.

KEY ISSUES:
• HAZARD COMMUNICATION
• HOT WORK CONTROL
• PLASTIC PIPE IN FLAMMABLE SERVICE
• FLAME ARRESTER MAINTENANCE
• FLORIDA PUBLIC EMPLOYEE SAFETY PROGRAMS

ROOT CAUSES:
1. The City of Daytona Beach did not implement adequate controls for hot work at the Bethune Point WWTP.
2. The City of Daytona Beach had a hazard communication program that did not effectively communicate the hazards associated with methanol at the Bethune Point WWTP.

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Image credit: CSB

A release of hot light hydrocarbon during the completion of a maintenance activity resulted in a major fire. The fire occurred on a residual fluid catalytic cracking (RFCC) unit that had recently been commissioned as part of a major expansion, doubling the overall refinery capacity. The fire resulted in the closure of the expanded area of the refinery while extensive rebuilding activity was delivered. The value of the property damage loss is currently estimated to be in excess of US$1 billion.

[ Property Damage $1000 Million. Estimated Current Value $1000 Million ]

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Image credit: ADNOC

Refinery and local fire fighters spent more than six hours battling a fire on a large oil refinery. A warning was issued to local residents because of thick nontoxic smoke generated from a stack on the site. The fire is thought to have broken out in a furnace. No injuries were reported.

[ Property Damage $150 Million. Estimated Current Value $162 Million ]

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Image credit: Essar

On the evening of January 12, 2009, 2 refinery operators and 2 contractors suffered serious burns resulting from a flash fire at the Silver Eagle Refinery in Woods Cross, Utah. The accident occurred when a large flammable vapor cloud was released from an atmospheric storage tank, known as tank 105, which contained an estimated 440,000 gallons of light naphtha. The vapor cloud found an ignition source and the ensuing flash fire spread up to 230 feet west of the tank farm.

On November 4, 2009, a second accident occurred at the Silver Eagle Refinery in Woods Cross, Utah, when a powerful blast wave – caused by the failure of a 10 inch pipe – damaged nearby homes.

KEY ISSUES:
• MECHANICAL INTEGRITY

ROOT CAUSES:
1. Sulfidation corrosion

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Image credit: CSB

On January 13, 2003, at approximately 4:30 pm, a vapor cloud deflagration and pool fire erupted at the BLSR Operating, Ltd. (BLSR), facility located 5 miles north of Rosharon, Texas. Two BLSR employees were killed, and three were seriously burned. Two T&L Environmental Services, Inc. (T&L), truck drivers, who had just delivered gas condensate storage tank basic sediment and water (BS&W) to BLSR, were seriously burned; one of these men died on March 2.

The fire was caused by the release of hydrocarbon vapor during the unloading of BS&W from two vacuum trucks into an open area collection pit. BS&W is an oil/gas exploration and production (E&P) waste liquid. The fire destroyed two 50-barrel (2,100-gallon) vacuum trucks and seriously damaged waste liquid offloading equipment and structures at BLSR. One of the vacuum truck diesel engines was the most likely source of ignition..

KEY ISSUES:
• RECOGNIZING FLAMMABILITY HAZARDS OF EXPLORATION & PRODUCTION WASTE LIQUIDS
• SAFE HANDLING OF FLAMMABLE LIQUIDS

ROOT CAUSES:
1. Noble Energy, Inc., the shipper, failed to identify the flammability hazard of BS&W generated at its gas well production facility, and also failed to communicate the hazard to employees and contractors who were required to handle the flammable liquid.
2. T&L management did not require Noble Energy to provide vacuum truck drivers with a material safety data sheet or other document listing the potential flammability hazard of BS&W, nor did it identify the flammability hazard of the mixture in the vacuum truck tank.
3. BLSR management did not have effective hazard communication practices in place to recognize the potential flammability hazard of each shipment of BS&W, nor did it implement safe handling practices when offloading flammable liquid onto the mud disposal and washout pad area.

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Image Credit: CSB