Incident Videos

On Wednesday 23 May 1984, a group of 44 people was assembled in a valve house set into a hillside at the outfall end of the Lune/Wyre Transfer Scheme at Abbeystead. The visitors were attending a presentation to allay anxieties on the effects of the installation on the winter flooding of the lower Wyre Valley.

As part of this presentation, water was to be pumped over the weir regulating the flow of water into the Wyre. Shortly after pumping commenced there was an intense flash, followed immediately by an explosion causing severe damage to the valve house.

Sixteen people were killed; no one escaped without injury from the valve house.

The explosion was caused by the ignition of a mixture of methane and air, which had accumulated in the valve house. The methane had been displaced from a void, which had formed in the end of the Wyresdale Tunnel during a period of 17 days before the explosion when no water was pumped through the system.

No source of ignition for the explosion has been positively identified. Thorough examination and testing of the electrical equipment has not revealed any faults likely to have caused ignition and there is insufficient evidence to confirm any of the other explanations which have been considered. Smoking in the Valve House was not prohibited because the likelihood of a flammable atmosphere arising there had not been envisaged.

KEY ISSUES:
• DESIGN CODES – PLANT
• LEAK / GAS DETECTION
• OPERATING PROCEDURES
• TRAINING

Report: https://www.icheme.org/media/13697/the-abbeystead-explosion.pdf

Image Credit: HSE

On May 24, 2017, an explosion occurred at the Midland Resource Recovery (MRR) facility in Philippi, West Virginia, killing two workers and severely injuring another worker. The founder and president of MRR was one of the victims. The CSB initiated an investigation of the incident and deployed an investigative team on May 28, 2017. While the CSB was investigating this incident, the MRR facility experienced a second explosion, on June 20, 2017. This explosion fatally injured a contractor employed by Specialized Professional Services, Inc. (SPSI). MRR had hired SPSI to perform investigation and mitigation work at its Philippi facility following the May 24, 2017, explosion.

The CSB determined that the probable cause of these incidents was reactive, unstable chemicals that exploded when workers tried to drain the uncharacterized, chemically treated liquid from natural gas odorizer equipment. The CSB investigation found that MRR lacked an effective safety management system to identify and control hazards from reactive chemicals. Among other things, MRR had no formal hazard identification process in place to analyze or characterize what chemicals were inside the odorizer vessels (and in what quantity) before decommissioning and chemically treating this equipment with sodium hypochlorite. The company also lacked effective safeguards to prevent unexpected or uncontrolled chemical reactions.

Following these catastrophic incidents, MRR asserts that it has stopped using reactive chemicals, including sodium hypochlorite, and the company now uses a proprietary process to remove the mercaptan smell from decommissioned odorization equipment.

KEY ISSUES:
• INEFFECTIVE MANAGEMENT OF REACTIVE CHEMICAL HAZARDS
• LACK OF A PROCESS SAFETY MANAGEMENT SYSTEM
• PERSISTING GAPS IN FEDERAL SAFETY REGULATIONS FOR REACTIVE CHEMICAL HAZARDS

ROOT CAUSES:
1. The company did not conduct a formal evaluation of the reactive chemistry, perform a hazard analysis, and ensure that sufficient safeguards are in place to prevent reactive chemical incidents.
2. The company did have a thorough and complete understanding of their reactive chemistry under design conditions and under all foreseeable abnormal conditions.

Image credit: CSB

A fire occurred in the terpene resin production line reactor overheating, and it damaged an area of 800-900 square meters

Proximate causes:
• Inadequate tools, equipment & vehicles (overheat from reactor of Terpene dilute resin leads the final pipeline explosion)

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

An abnormal chemical reaction occurred during the batch production of a thermoplastic rubber product, resulting in an explosion at this plant. As a result of the explosion the reactor, process controls, accessories, control room, and building for this production unit were completely destroyed.

The fire then spread to involve part of the tank farm, resulting in the destruction of five atmospheric storage tanks. At approximately 12:30, the first of four one million US gallon and a 500,000 US gallon styrene storage tanks exploded. A fire fighting attack using cooling water and foam hose streams was used to prevent the fire from involving other nearby storage tanks, two of which contained butadiene. The fire was extinguished after approximately nine hours.

[ Property Damage $182 Million. Estimated Current Value $363 Million ]

Image credit: Mike Cottrell

Six people were killed and five others injured after a suspected explosion hit a hydropower plant in southwest China’s Yunnan Province on Friday.

The emergency management department of Yunnan said the accident happened at 11:10 a.m. at the Sinanjiang Hydropower Station in Mojiang County. It happened as workers were dredging the dam’s ventilation tunnel.

Authorities said the rescue operation had been completed and the injured were not in a life-threatening condition. An investigation has been launched into the cause of the accident

Image Credit: TN

On 29th May 2000 at 18:07 p.m. all power was lost to No. 1, 5 & 10 electrical substations that supply electrical power to the North Side of the Complex which contains the Oil Refinery, various chemical plants, utility plants and logistics facilities.

As a result, emergency shutdown of the Oil Refinery and the chemical plants on the North Side occurred and the utility plants were also affected due to a loss of power to the main cooling water pump systems. (There was some smoky flaring visible as a result of the emergency shutdown.)

In addition because of the duration of the power failure, a controlled shutdown of some other facilities elsewhere on-site (some chemical plants on the South Side and the Kinneil operations) was also necessary because the supply of steam for the correct operation of the flare system could not be maintained.

The HSE concluded that the power loss which occurred on the 29th May 2000 was caused by an earth fault on a 33kV underground power cable between No.1 and No.5 sub-station and the failure of the 33kV circuit breaker in No.1 sub-station to trip and clear the fault.

The source of the earth failure was not immediately apparent. The cable which failed was situated in the bottom part of the excavated trench, almost in the side wall of the trench and only protruded from its protective cable tile over a short length.

The fault was ultimately cleared by two 33kV circuit breakers in No.2 electrical sub-station resulting in power loss to No.1, No.5 and No.10 electrical sub-stations.

The immediate cause of the power distribution failure was a combination of two direct causes:

The Earth Fault
Forensic evidence indicated that the earth fault was caused by physical damage to the cable from an air powered tool known as a clayspade.The
clayspade equipment was operated by a number of different personnel during the construction of the trench and the cable was protected over the majority of its length, except in the location where the damage occurred, by the protective cable tile system. All personnel were aware of the responsibility to report any problems during the construction of the trench but none were reported. As a result of the damage the integrity of the lead sheath on the cable was breached, allowing water ingress, weakening of the cable’s insulation and the resultant earth fault.

Circuit Breaker Failure
The cable fault described above should have caused the 33kV circuit breaker in No.1 electrical sub-station to operate and clear the fault. However it failed to operate because its earth protection relay had been disabled by two small sections of plastic (cable ties with the ends cut-off) inserted in the connections between the relay and its current transformer. This meant that the earth fault protection relay was disabled and would not operate.

The power distribution failure had the potential to cause fatal injury and environmental impact, although no serious injury occurred, and there was only short term impact on the environment.

KEY ISSUES:
• Systems of work;
• The clarity and adequacy of instructions;
• The adequacy of supervision;
• Operatives behaviour;
• BP planning processes;
• Risk assessments carried out by the contractors;
• Details in the method statements;
• Inconsistent and different methods of application of the permit-to-work (PTW) system;
• Procedures, systems of work and test equipment for the testing of the 33kV circuit breaker;
• Implementation of maintenance policies.

Image Credit: HSE

A failure led to the release of light hydrocarbons that dispersed and found an ignition source. An intense fire followed in the tank farm. After less than five minutes, a 5,000-bbl storage sphere failed, resulting in a large fireball and rocketed pieces of the sphere throughout the plant. Within the next 20 minutes, five 1,000-bbl horizontal vessels, four 1,000 bbl vertical vessels, and one additional 5,000 bbl sphere failed, either as a result of missile damage or due to a boiling liquid expanding vapor explosion (BLEVE). Pieces of the tanks travelled in all directions, falling into operating units and tank farms, starting more fires. Fragments also hit the firewater storage tank and electric fire pumps, leaving only the two diesel fire pumps operational.

[ Property Damage $55 Million. Estimated Current Value $211 Million ]

Image credit: Valero

A fire and subsequent explosion near the distillation unit on the refinery resulted in the whole site’s shutdown, which is expected to last up to 12 months.

At approximately 11:00 PM on May 31, 2017, explosion(s) at the Didion Milling (Didion) facility in Cambria, Wisconsin, resulted in 5 worker deaths and an additional 14 workers injured. Because the event occurred at night, only 19 employees were working within the facility at the time of the incident.

Shortly before the explosion(s) at Didion, workers saw or smelled smoke on the first floor of one of the mill buildings. In trying to find its source, workers focused on a piece of equipment called a gap mill. While inspecting the equipment, workers witnessed a filter connected to an air intake line for the mill blow off, resulting in corn dust filling the air, and flames shooting from the air intake line, followed by one or more explosions..

KEY ISSUES:
• DUST HAZARD AWARENESS
• DUST LEVEL PERCEPTION

Image credit: CSB

At about 16:53 hours on Saturday 1 June 1974 the Nypro (UK) site at Flixborough was severely damaged by a large explosion. Twenty-eight workers were killed and a further 36 suffered injuries. It is recognised that the number of casualties would have been more if the incident had occurred on a weekday, as the main office block was not occupied. Offsite consequences resulted in fifty-three reported injuries. Property in the surrounding area was damaged to a varying degree.

Prior to the explosion, on 27 March 1974, it was discovered that a vertical crack in reactor No.5 was leaking cyclohexane. The plant was subsequently shutdown for an investigation. The investigation that followed identified a serious problem with the reactor and the decision was taken to remove it and install a bypass assembly to connect reactors No.4 and No.6 so that the plant could continue production.

During the late afternoon on 1 June 1974 a 20 inch bypass system ruptured, which may have been caused by a fire on a nearby 8 inch pipe. This resulted in the escape of a large quantity of cyclohexane. The cyclohexane formed a flammable mixture and subsequently found a source of ignition. At about 16:53 hours there was a massive vapour cloud explosion which caused extensive damage and started numerous fires on the site.

Eighteen fatalities occurred in the control room as a result of the windows shattering and the collapse of the roof. No one escaped from the control room. The fires burned for several days and after ten days those that still raged were hampering the rescue work.

KEY ISSUES:
• PLANT MODIFICATION / CHANGE PROCEDURES
• DESIGN CODES – PIPEWORK
• MAINTENANCE PROCEDURES
• PLANT LAYOUT
• CONTROL ROOM DESIGN
• OPERATING PROCEDURES
• INERTING

Report: https://www.icheme.org/media/13689/the-flixborough-disaster-report-of-the-court-of-inquiry_repaired.pdf

Image Credit: Scunthorpe Telegraph (George Schofield)

Shortly after 6pm, on 2 June 2011, an atmospheric storage tank within the amine regeneration unit at the Chevron Pembroke Refinery exploded. A fireball split the tank open and killed four workers: Robert Broome, Julie Jones, Dennis Riley and Andrew Jenkins. The sole survivor, Andrew Phillips, sustained severe burns and suffered life-changing injuries.

The force of the explosion ejected the five-tonne steel tank roof over 55 metres through the air. After narrowly missing a multi-fuel pipe track, the roof crashed onto a pressurised storage sphere containing extremely flammable butane. Good fortune prevented the airborne roof from puncturing the butane storage vessel, which would have led to an uncontrolled release of liquified petroleum gas (LPG).

The explosion was caused by the unintended ignition of a flammable atmosphere within the tank (17T302), during what should have been a routine cleaning operation conducted in preparation for maintenance.

KEY ISSUES:
• OPERATING PROCEDURES
• PERMIT SYSTEM
• CONTROL OF CONTRACTORS
• RISK ASSESSMENT
• COMPETENCE

Image Credit: HSE

10 workers have now died following an explosion on 3 June, at a chemicals factory in India, reports news agency The Indian Express. Reportedly, more than 70 others were injured.

The blast occurred at a facility owned by specialty chemicals and intermediates company Yashashvi Rasayan, in an industrial area located in Dahej, in the Bharuch district of Gujarat, India. New Delhi Television (NDTV) reports that the ensuing fire engulfed the entire factory.

The Indian Express reports that at the time of the blast nearly 150 employees were inside the factory. Of the 77 injured workers admitted to hospitals for treatment, 33 have now been discharged. Two workers are in critical condition, according to M D Modia of the General Administration Department of the Gujarat Government.

Following the explosion – reportedly heard from 3 km away – around 4,800 people were evacuated from the nearby villages of Lahki and Luvara, says another report from The Indian Express. According to Times Now, Modia said this was due to the presence of poisonous chemicals. The Indian Express reports that it was as a precautionary measure. It is not noted whether residents have yet returned to their homes.

According to The Indian Express, the Gujarat Government issued a closure notice to Yashashvi Rasayan for the site where the incident took place, and additionally ordered an audit of all the factories in Dahej. The report added that according to an official release from Vipul Mittra of the Gujarat Government, “[t]he unit will not be allowed to resume operations, until adequate safety measures are in place”.

N D Vaghela, Assistant Director in the Office for Industrial Safety & Health, reportedly said that the blast occurred in a chemical tank and damaged others. Reportedly, officials are unable to enter the storage area for now.

The Indian Express reports that the cause of the blast is currently unknown, according to Vaghela. A previous report from The Indian Express said the explosion was caused by an unknown reaction between two containers, and reports from other outlets have referred to the explosion as a boiler blast.

Image Credit: Times of India

On the evening of June 3rd 2014 two major explosions and subsequently, a fire occurred at a Shell Moerdijk petrochemical plant. The explosions could be heard within a 20-kilometre radius. Debris from the explosion was found 800 metres away. Two employees were injured in the explosion. The Dutch Safety Board investigated this incident focusing on the immediate and underlying causes of the explosions. Besides that, also the firefighting and crisis management were investigated.

KEY ISSUES:
• Management of change is vital to identify new hazards
• Knowledge transfer between the design phase and the operations phase is critical

Image Credit: Dutch Safety Board

A gas release from a corroded pipeline resulted in an explosion at a gas plant. This resulted in a 30% reduction in the Australian state’s domestic gas supply and a 45% reduction in the supply of gas to mines and other industries. Workers were evacuated from the island as a precaution. It took six months before the plant was returned to full capacity operation.

[ Property Damage $120 Million. Estimated Current Value $143 Million ]

Image credit: WA News

A well-intervention vessel lost power and collided with an unmanned platform forming part of this 230,000 bbl per day complex. Heavy damage was caused to the vessel and the platform, including damage to the platform structure, linking access bridge, and well equipment. Some 23,000 bbl per day of oil production was reportedly affected. The force of the collision caused the bow of the vessel to compress by about two meters, with the platform pushed partly out of position, loosening several support legs from the main load-bearing structure. One of the water injection risers on the platform was bent extensively and several wellheads were moved, with a catalog of further damage from the collision also identified.

[ Property Damage $750 Million. Estimated Current Value $909 Million ]

Image credit: No credit

An explosion at the Partridge-Raleigh oilfield in Raleigh, Mississippi. The incident occurred at about 8:30 a.m. on June 5, 2006, when Stringer’s Oilfield Services contract workers were installing pipe from two production tanks to a third. Welding sparks ignited flammable vapor escaping from an open-ended pipe about four feet from the contractors’ welding activity on tank 4. The explosion killed three workers who were standing on top of tanks 3 and 4. A fourth worker was seriously injured.

KEY ISSUES:
• HOT WORK CONTROL
• SAFE WORK PRACTICES AT OIL & GAS PRODUCTION WELLS

ROOT CAUSES:
1. A gas detector was not used to test for flammable vapor.
2. ‘Flashing’ tanks containing hydrocarbons with a lit oxy-acetylene torch to determine the presence of flammable vapor is unsafe and extremely dangerous.
3. The open pipe on the adjacent tank was not capped or otherwise isolated.
4. A makeshift work platform – a ladder placed between the tanks – was used.
5. All tanks were interconnected and some of the tanks contained flammable residue and crude oil.

Image credit: CSB

Around 21,000 t of diesel has leaked into a Russian river near Norilsk, which is inside the Arctic circle, after a storage tank collapsed. It is believed that posts supporting the tank sank due to melting permafrost following unusually warm weather.

The spill occurred at a heat and power plant operated by Norilsk-Taymyr Energy Company (NTEC), a subsidiary of Norilsk Nickel, on 29 May. According to Norilsk Nickel, around 21,000 t of diesel leaked into the Ambarnaya river. The company said that supporting posts at the base of a storage tank suddenly sank. Sergey Dyachenko, First Vice President and Chief Operating Officer of Norilsk Nickel, said: “We can assume that abnormally mild temperatures could have caused permafrost thawing resulting in partial subsidence of the tank’s supports.”

NTEC teams are currently assessing the risk of sinking soil under hazardous objects installed in permafrost. Dyachenko said that the tanks are inspected every second year so that negligence was not the cause of the collapse.

A fire also occurred on the site after a car came into contact with the leaked fuel, causing a fire around 300 m2 in area. The fire was contained and extinguished and the driver did not sustain any injuries.

Image Credit: Getty

An 18″ medium pressure (MP) steam main located near to the A904 Bo’ness road ruptured at 23:18 p.m. on 7th June 2000 resulting in a significant loss of MP steam directly into the atmosphere. The steam leak damaged fencing immediately adjacent to the ruptured pipework. Debris and steam was blown across the road until the leak was isolated. The leak also caused significant noise (similar to a jet engine) being heard in the Grangemouth area. A member of the public walking the dog 300 metres away sustained rib injuries from tripping over the dog.

There was significant disruption to the steam supply system for the Complex for approximately one hour until the steam leak could be isolated and as a result of the incident the A904 Bo’ness road was closed for public access until 22nd June whilst repairs were carried out.

The medium pressure (MP) steam main rupture had the potential to cause fatal injury and environmental impact, although no serious injury occurred, and there was only short term impact on the environment.

The critical factors that led to the incident were created a week earlier. Significant levels of condensate built up in the steam line following isolation of a steam trap to gain access for inspection of the tunnel, after the culvert was flooded following the power distribution failure.

The immediate cause of the catastrophic failure of an MP steam distribution pipeline was “condensation induced water hammer” which caused gross overpressure.

KEY ISSUES:
• Management of change (change control procedures);
• Failure to adequately investigate significant plant upsets and to carry out risk assessments;
• Operating regimes and lack of certain site standards;
• Inspection and maintenance of equipment;
• Management structure and organisation;
• Failure to learn lessons from previous incidents/events on-site.

Image Credit: HSE

On June 7, 2010, at 2:40 p.m., a truck-mounted power auger (auger truck) operated by C&H Power Line Construction (C&H) struck and punctured a 36-inch-diameter natural gas transmission pipeline operated by Enterprise Products Operating, LLC (Enterprise). C&H, a contractor working for Brazos Electric (Brazos), was using the auger truck to dig holes for the installation of new electric service utility poles.

The accident occurred about 45 miles southwest of Fort Worth, Texas, near the town of Cleburne. The natural gas ignited and killed the auger operator and burned six workers, who were transported to a nearby hospital for treatment. The pipeline had a maximum allowable operating pressure (MAOP) of 1,051 pounds per square inch, gauge (psig) and was operating at 950 psig at the time of the accident. Total property damage and clean-up costs were estimated to be $1,029,000.

A contractor died after entering a confined space at Dow Chemical’s plant in Oyster Creek.

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

An explosion and fire occurred at one of manufacturing plant’s process units at Eastman Chemical Resins in Jefferson Hills. The fire was extinguished about 2 h after it began. Shelter-in-place order was issued

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

Fire and explosions occurred at the Miller Chemical and Fertilizer Complex, which blended raw materials to manufacture agricultural products

Damage to the facility: $20 million dollars/Shelter-inplace within a mile radius of the warehouse

Proximate causes:
• Defective equipment

Source: A web-based collection and analysis of process safety incidents (https://www.sciencedirect.com/science/article/abs/pii/S0950423016302285)
Image Credit: 911 Photography

On June 9, 2009, a major natural gas explosion heavily damaged the ConAgra Slim Jim meat processing factory in Garner, North Carolina, just south of Raleigh. Three workers were crushed to death when a large section of the building collapsed. The explosion critically burned four others and sent a total of 71 people to the hospital including three firefighters who were exposed to toxic anhydrous ammonia from the plant’s refrigeration system. Approximately 18,000 pounds of ammonia were released to the environment and 100,000 square feet of the plant were damaged. Due to the severity of the structural collapse, there was the potential for numerous additional deaths or serious injuries.

KEY ISSUES:
• DIRECTLY VENT PURGED GASES TO A SAFE LOCATION OUTDOORS, AWAY FROM PEOPLE AND IGNITION SOURCES.
• USE COMBUSTIBLE GAS DETECTORS TO MONITOR THE GAS CONCENTRATION DURING PURGING OPERATIONS.
• ENSURE PERSONNEL INVOLVED IN GAS PURGING OPERATIONS ARE FULLY TRAINED.

ROOT CAUSES:
1. Purging into equipment vicinity is common practice

Image credit: CSB

There was a chemical leak in a cracking unit at Dow Chemical’s Oyster Creek Plant. In this incident the release did not result in a fire. Nearby residents and employees were asked to stay indoors

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

The Fluidised Catalytic Cracker Unit situated on the Oil Refinery had been shut down on 29th May 2000 following the power distribution failure. On 10th June 2000 at approximately 03:20 a.m. during start up procedures which commenced on 9th June there was a significant leak of hydrocarbons from the Fluidised Catalytic Cracker Unit (FCCU or Cat Cracker) creating a vapour cloud which ignited resulting in a serious fire. On and off-site emergency services were mobilised, the BP Incident Management Team (IMT) were called in and the Grangemouth Petrochemicals Complex Major Incident Control Committee (MICC) was convened. The fire was brought under control in approximately 90 minutes and totally extinguished by 10:30
a.m.

During the fire and in the fire-fighting efforts some damage resulted to asbestos cladding surrounding pipework and vessels. Some hydrocarbons in the contaminated firewater run-off were discharged directly into the River Forth.

No injuries occurred to the workers in the vicinity. They followed the emergency response procedures. However, there was the potential for injury to people and greater damage to equipment.

1. The primary immediate cause of the FCCU incident was the fracture of an unsupported 6×3″ reducing tee branch pipe to the main transfer line between the Debutaniser column (E5) and the Re-run column (E6) due to fatigue failure. This resulted in the release of highly flammable liquid/vapour at elevated temperature and pressure, which subsequently ignited.
2. It was fortunate that no fatal or serious injury occurred to the four or five workplace members in the immediate vicinity. This was due to a combination of the way the fire started and progressed, and the workers positioning at the time of the incident and presence of mind to move to safe positions. Weather conditions assisted and the vapour did not accumulate in and around the buildings or in the plant. Under different circumstances this could have led to a vapour cloud explosion, (a scenario envisaged in the CIMAH safety report), which would have increased the likelihood of fatal injuries and further escalation of the incident.
3. There were serious operational problems associated with the FCCU stage two modifications in 1997/98 which were a relevant underlying cause of the major accident on 10th June. These were inadequately dealt with by BP despite recommendations in writing from the HSE to review the process after the torch oil explosion late in 1999.
4. BP reviewed the FCCU earlier in 2000, partly to try to determine why it was not operating properly (eventually traced to a blocked cyclone dip leg) and to compare it with BP FCCU world standards. The review findings were not implemented or communicated properly.

The Fluidised Catalytic Cracker Unit (FCCU) fire had the potential to cause fatal injury and environmental impact, although no serious injury occurred, and there was only short term impact on the environment.

KEY ISSUES:
• Organisational structure – the HSE accept that these were historic and had been identified by BP who were taking steps to address the issue when the incidents occurred;
• Operational review system;
• Maintenance of integrity of pipework to avoid loss of containment scenarios;
• Risk assessment procedures;
• Consideration of Human Factors issues.

Image Credit: HSE

On 11 June 1987 a team of four contractors was cleaning a crude oil storage tank at the Dalmeny Oil Storage Terminal. The tank was of the floating roof type and the roof had been lowered due to the tank being empty. It was resting on a series of 219 support pillars. Three of the contractors worked inside the tank with one on duty outside along with a BP employee.

The tank had been emptied of its contents and three roof manhole covers opened to allow natural ventilation. However, the evolution of a vapour with the risk of forming an explosive atmosphere was not considered sufficient to merit either mechanical ventilation or rigorous monitoring of the vapour concentrations within the tank. As a precaution though, the workers were required to wear airline-breathing apparatus supplied by a compressor located outside the tank bund.

At 13:20 hours the outside man looked in and saw a ring of fire surrounding the three men. Two of the employees managed to escape the fire but the third man died from the effects of asphyxiation and burns. The fire escalated rapidly with flames and smoke coming out of the open man ways.

The cause of the accident was one of the contractors smoking inside the oil tank. It was apparently common practice for the workers to remove their breathing apparatus while inside the tank, with some workers choosing to smoke while the supervisor was not looking. On this occasion one of the men working in the tank had dropped a lit cigarette on to the floor where it had ignited the crude oil.

KEY ISSUES:
• MAINTENANCE PROCEDURES
• SITE SECURITY
• HAZARDOUS AREA CLASSIFICATION / FLAMEPROOFING
• TRAINING
• ISOLATION

Report: https://www.icheme.org/media/13700/the-fires-and-explosion-at-bp-oil-grangemouth-refinery-ltd.pdf

Image Credit: HSE

On June 10, 2008, Goodyear operators closed an isolation valve between the heat exchanger shell (ammonia cooling side) and a relief valve to replace a burst rupture disk under the relief valve that provided over-pressure protection. Maintenance workers replaced the rupture disk on that day; however, the closed isolation valve was not reopened.

On the morning of June 11, an operator closed a block valve isolating the ammonia pressure control valve from the heat exchanger. The operator then connected a steam line to the process line to clean the piping. The steam flowed through the heat exchanger tubes, heated the liquid ammonia in the exchanger shell, and increased the pressure in the shell. The closed isolation and block valves prevented the increasing ammonia pressure from safely venting through either the ammonia pressure control valve or the rupture disk and relief valve. The pressure in the heat exchanger shell continued climbing until it violently ruptured at about 7:30 a.m.

The catastrophic rupture threw debris that struck and killed a Goodyear employee walking through the area. The rupture also released ammonia, exposing five nearby workers to the chemical. One additional worker was injured while exiting the area.

KEY ISSUES:
• EMERGENCY RESPONSE & ACCOUNTABILITY
• MAINTENANCE COMPLETION
• PRESSURE VESSEL OVER-PRESSURE PROTECTION

ROOT CAUSES:
1. Although maintenance workers had replaced the rupture disk by about 4:30 p.m. on June 10, the primary over-pressure protection for the heat exchanger remained isolated until the heat exchanger ruptured at about 7:30 a.m. on June 11.

Image credit: CSB

The June 13, 2013 catastrophic equipment rupture, explosion, and fire at the Williams Olefins Plant in Geismar, Louisiana, which killed two Williams employees. The incident occurred during nonroutine operational activities that introduced heat to a type of heat exchanger called a ‘reboiler’ which was offline, creating an overpressure event while the vessel was isolated from its pressure relief device. The introduced heat increased the temperature of the liquid propane mixture confined within the reboiler shell, resulting in a dramatic pressure rise within the vessel due to liquid thermal expansion. The reboiler shell catastrophically ruptured, causing a boiling liquid expanding vapor explosion (BLEVE) and fire.

Process safety management program weaknesses at the Williams Geismar facility during the 12 years leading to the incident caused the reboiler to be unprotected from overpressure.

KEY ISSUES:
• OVERPRESSURE PROTECTION
• PROCESS HAZARD ANALYSIS
• MANAGEMENT OF CHANGE
• PRE-STARTUP SAFETY REVIEW
• OPERATING PROCEDURES
• HIERARCHY OF CONTROLS
• PROCESS SAFETY CULTURE

ROOT CAUSES:
1. Williams did not perform the 2001 MOC until after the plant was operating with the valves installed, and the associated PSSR was incomplete. These actions did not comply with facility (and regulatory) safety management system requirements; however, Williams management accepted both of these practices;
2. Car seals are low-level, administrative controls, but they were the favored safeguard in the 2006 PHA recommendation to prevent overpressure events. Williams Geismar did not have a policy requiring the effectiveness of safeguards to be analyzed;
3. Williams Geismar did not follow OSHA PSM regulatory requirements that operations activities have an associated procedure to safely conduct the work. For example, Williams did not create a procedure specifically for switching the propylene fractionator reboilers Such a procedure should have alerted the operations personnel of the overpressure hazard;
4. The Williams PHA policy did not require effective action item resolution and verification, resulting in incorrect action item implementation in the field;
5. The Williams PHA policy did not require PHA teams to effectively evaluate and control risk; and
6. Operations personnel had informal authorization to manipulate field equipment as part of assessing process deviations without first conducting a hazard evaluation and developing a procedure.

Image & AcciMap Credit: CSB

An epoxyethane device got exploded and then triggered a fire. The fire spread to three of six chemical tanks nearby. Each tank has a storage capacity of 1000 cubic meters. More than 200 fire fighters arrived at the site to put out the fire.

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

On the morning of June 14, 2006, an operator was mixing and heating a flammable mixture of heptane and mineral spirits in a 2,200-gallon open top tank equipped with steam coils. The finished product, ‘Super Clean and Tilt’ is a proprietary mixture, which is applied to cured concrete surfaces to prevent bonding with wet concrete.

As the operator was adding an ingredient to the batch, he observed a ‘dense fog’ accumulating on the floor below the tank. He immediately notified a senior operator who helped him shut down the operation. They both exited the building and advised workers in adjoining areas to leave.

As the vapor cloud spread throughout the mixing area and surrounding workspaces, other employees exited the building.

Within about 10 minutes after the operator first observed the vapor cloud, most employees who were working in the area had evacuated. A contracted delivery driver passed some of these employees as he walked into the building and into the spreading vapor cloud. The cloud ignited within seconds of him entering. The driver died several days later from the burns he received.

The pressure created by the ignition blew the doors open to an adjacent area, injuring a temporary employee. This employee suffered second-degree burns and was hospitalized for three days. .

KEY ISSUES:
• FLAMMABLE LIQUID PROCESS DESIGN
• ENGINEERING CONTROLS
• PLAN REVIEW & CODE ENFORCEMENT
• EMERGENCY PREPAREDNESS

ROOT CAUSES:
1. The process was not designed and constructed in accordance with fire safety codes and OSHA regulations.
2. The Fire Department did not require UFC to comply with critical safety requirements (local exhaust and floor level ventilation)
3. The facility was unprepared for an emergency release of this magnitude.

Image credit: CSB

One of the worst workplace tragedies in Montreal history, the explosion of the tanker Cymbeline while it was being repaired at the Canadian Vickers Co. dry dock in the east end.

The initial blast at 4:20 a.m., thought to have been sparked by a rivet puncturing an oil tank, was followed by another an hour later, propelling bodies into the St. Lawrence and showering burning oil on anyone and anything in proximity. More than 30 men perished, among them Montreal fire chief Raoul Gauthier and three other firefighters. Dozens more suffered burns and other injuries.

KEY ISSUES:
• Tanks should be free of flammable vapour before any hot work is performed
• Care must be taken when responding to an incident to ensure you are not in harms way

Image Credit: Montreal Gazette

An explosion occurred in a thermal power generation company preparation plant

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

Three killed when feeding additives bnaphthalene sulfonate to a reaction pool at a chemical fertilizer company.

Proximate causes:
• Failure in following procedure (Improper operation)

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

A gas explosion occurred in confined space in coal mine industry

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

4 killed in a gas explosion happened in the coal mine in Enshi city.

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

At approximately 4 am on Friday June 21, 2019 there was a release of vapor in the PES refinery alkylation unit. The vapor found an ignition source, causing a fire and multiple explosions.

KEY ISSUES:
• MECHANICAL INTEGRITY
• HF CORROSION

Image credit: CSB

Ethanol vapors leaked from piping caught fire and caused an explosion at the Poet Ethanol Plant in Glenville. Two out of four employees that were in the plant were injured. Significant damage to the facility

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

An explosion and large fire occurred in the olefins plant Number III at a petrochemical plant. The explosion was felt and heard more than 10 miles away and the ensuing fire burned for approximately 10 hours. The explosion and fire resulted in extensive damage to the facility and several workers received minor injuries. In addition, nearby properties were damaged, nearby transport routes were closed for several hours, and residents were advised to remain indoors. The incident originated at the cracked gas compressor system in the olefins unit and was caused by the structural failure of a 36-inch pneumatically-assisted non-return valve located on a high-pressure light hydrocarbon gas line. The escaping gas formed a vapor cloud and eventually found a source of ignition, resulting in the unconfined vapor cloud explosion.

[ Property Damage $135 Million. Estimated Current Value $250 Million ]

Image credit: Roy Luck

St. Louis was experiencing a heat wave with bright sunlight and temperatures reaching 97 °F (36 °C) on June 24, 2005. Praxair operations proceeded normally during the morning and early afternoon; however, about 3:20 pm, a technician retrieving cylinders from an outside storage area saw a ten-foot high flame coming from a cylinder and activated the fire alarm. Security camera video from the facility shows the release and ignition of gas from a cylinder in the propylene return area.

As workers and customers evacuated, the fire spread to adjacent cylinders. Security camera video shows nearby cylinders igniting in the first minute. At 2 minutes, cylinders begin exploding, flying into other areas of the facility, and spreading the fire. After 4 minutes, the fire covers most of the facility’s flammable gas cylinder area and explosions are frequent.

KEY ISSUES:
• HIGH AMBIENT TEMPERATURES
• RELIEF vs VAPOR PRESSURE
• FLAMMABLE GAS DETECTION
• DELUGE SYSTEMS
• FIRE BARRIERS

ROOT CAUSES:
• Although the official cause is undetermined, the most likely cause was ‘propylene venting due to the prolonged exposure to excessive heat’

Image credit: CSB

A tank containing chlorine exploded at the Olin Chlor Alkali Products plant in Becancour. Workers in nearby buildings were evacuated, but employees at Olin Chlor Alkali were told to remain at the chemical plant.

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

An explosion occurred when employees were attempting to isolate a leak on a condensate line between the natural gas liquid (NGL) plant and the refinery. Three crude units were damaged and two reformers were destroyed. The fire was extinguished approximately nine hours after the initial explosion. Five people were killed and 50 others were injured. The initial investigation into the loss indicated a lack of inspection and maintenance of the condensate line, which was not owned by the refinery. A lack of clear understanding of the ownership of the line is thought to have delayed the isolation of it.

[ Property Damage $412 Million. Estimated Current Value $718 Million ]

KEY ISSUES:
• Ownership and responsibility for equipment should be understood
• Third party interfaces must be managed
• Quality maintenance and inspection regimes are critical for plant integrity

Image credit: KNPC

A natural gas pipeline explosion and fire occurred at a gas booster station as a crew worked on a 4-inch gas line. The workers were replacing some gas lines, repairing a ruptured line.

Source: A web-based collection and analysis of process safety incidents (https://www.sciencedirect.com/science/article/abs/pii/S0950423016302285)
Image Credit: News Channel 10 Amarillo

At approximately 17:10 hours on the 27th June 1976 an explosion occurred killing one man and causing extensive damage to the plant and adjacent buildings.

The explosion involved a detonation of zoalene, which is used as a poultry feed additive.

The following factors may have contributed in the circumstances leading up to the explosion:
– the batch probably contained a higher percentage of impurities than most other batches due to the presence of rewashed material, some of which may have been subjected to a number of heating cycles;
– the long holding period (greater than twenty-four hours) of the material at an elevated temperature in the dryer vessel, when this material was known to have a history of thermal instability;
– the drying vessel was not cooled which was previously carried out during the former manufacturing process. The cooling was undertaken for ease of handling rather than for material safety;
– overheating of the batch material; and
– the absence of accurate process temperature and moisture indication.

The fundamental reason for this incident was a general lack of knowledge of the destructive potential of zoalene at adiabatic conditions. Neither the management nor the operating personnel were criticised for undertaking and conducting the operations that led to the explosion

KEY ISSUES:
• REACTION / PRODUCT TESTING
• PLANT MODIFICATION / CHANGE PROCEDURES

Report: https://www.icheme.org/media/13691/the-explosion-at-appleby-frodingham-steelworks-scunthorpe.pdf

Image Credit: HSE

During the night of June 27, 2016, the two personnel on duty at PGP – a control board operator and an outside operator – were stopping production of natural gas liquids due to pipeline problems downstream of the facility. Although this was a non-routine activity, the control board operator had experience conducting the procedure. The operators initiated the necessary steps from the control room, when, at 11:22 p.m., a sudden explosion and fire occurred. No abnormal alarms or other indicators warned the two PGP personnel of any problems. Within a minute of the initial explosion, the operators activated the emergency shut down systems at the plant and sheltered in the control room.

Over the course of the incident, the site experienced 13 different ruptures of piping and equipment. The CSB concludes that the first loss of containment most likely originated at a BAHX when it lost core integrity due to accumulated thermal fatigue.

The BAHX of interest was part of A-Train, one of three process lines (A, B, and C) at PGP. The rupture released flammable hydrocarbon into the process area in and around a variety of potential ignition sources. After ignition, emergency systems depressurized the plant and sent much of the process fluids to a flare, but the rupture also caused a portion of A-Train’s contents to continue to feed the fire, which intensified several times over approximately the next 35 minutes as additional piping and equipment failed. Equipment, piping, and vessels in the A-Train process area were extensively damaged .

KEY ISSUES:
• EXCHANGER FAILURE DUE TO THERMAL FATIGUE
• SERVICE LIFE DETERMINATION OF BRAZED ALUMINUM HEAT EXCHANGERS
• SOCIAL MEDIA USE IN EMERGENCY RESPONSE

ROOT CAUSES:
1. The absence of a reliable process to ensure the mechanical integrity of the heat exchanger contributed to the catastrophic failure of the equipment.

Image credit: CSB

Flammable color powder exploded in at a recreational water park in Taiwan

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

On the morning of Sunday 27 June 1982 two explosions occurred at the premises of Staveley Chemicals Limited. The source of the explosions was a pit containing drums of sulphur trioxide and of oleum. The drums of sulphur trioxide had been returned from customers more than 10 years previously and had then been stored in the open. Over the following years minor leaks developed through corrosion, and sulphur trioxide vapour began to escape as a visible fume. In November 1981 the company decided to overcome the problem by surrounding the drums with an absorbent solid. A pit was dug out on some open land within the works site, the drums placed within the pit, then covered over with a proprietary absorbent material and topped with crushed blast furnace slag. No special provision was made for drainage of the pit, nor to prevent ingress of ground water or rain. Drums of oleum were included together with the drums of sulphur trioxide in the pit.

The first explosion occurred at 10:45 hours on June 27th. Two drums were blown out of the site, over a public highway, to fall into open ground outside the works boundary and about 300 metres from the containment pit. Fortunately no injury to persons or damage to property was caused by these events. Further, but less intense explosions continued until the following day. A cloud of white acid mist billowed up from the site.

The Fire Brigade could not use water hoses because of the possibility of causing a violent reaction with any escaping oleum or liquid sulphur trioxide within the containment pit. It was decided that the best immediate course of action would be to put anhydrous sodium sulphate powder into the open pit in order to absorb liquid and suppress fuming. Several bags of this powder were thrown in and by 12:00 hours the mist emission was lessening. However, a second explosion occurred at 12:30 hours with a large release of acid mist but without ejecting any drums. There was a third explosion at about 14.30 hours. Tarpaulins were put over the pit to prevent the ingress of rain. The last explosion was at about 03:00 hours, the following morning. This explosion was minor compared with those on the previous day.

On Monday 28 June, a heavy steel grid was placed over the pit to reduce the risk of further drums being ejected. Temperature measurements were made in the pit, and found to be as high as 90°C in places. Subsequently the drums were all taken out of the pit and put on to open ground nearby. There were 32 sound drums remaining, and 25 corroded and empty or nearly empty.

KEY ISSUES:
• DRUM / CYLINDER HANDLING

Image Credit: YouTube (Hollingwood Lad)

An explosion and fire was caused by the failure of ammonia synthesis equipment

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

On 29 June 2009, shortly before midnight, a train transporting LPG from the oil refinery of Trecate, near Milan, to a LPG storage depot located in Gricignano, near Naples derailed while crossing Viareggio station and five of fourteen rail tankers overturned. Approximately 45 tonnes of LPG was released and the gas cloud spread to the neighbouring residential area before igniting. Thirty-one people died as a result of the accident and the damage caused ran into tens of millions of euros. The accident was the worst railway accident in Italy related to the transportation of dangerous substances, and the most serious accident in Italy involving LPG.

The management faults identified as possible factors in the Viareggio accident point to the need for more emphasis on risk assessment procedures in the rail transport of dangerous substances.

Ref: IChemE Loss Prevention Bulletin, Issue 231, page 4
Image Credit: RTBF

An explosion occurred in a petrochemical company in Xiangtan Jiuhua Industrial Zone. There was huge smoke

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

Gas leakage and explosions happened in the Mao Dongsheng industrial zone. It was reported that the spill affected 56 primary schools students and a teacher, and they were then sent to the hospital.

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

The Fateh Field L-3 development well had reached 4,180ft when a “kick” occurred. The kick control effort was terminated and the rig abandoned when gas broke around the 20-inch shoe and bubbled up under the platform.

Eight days after the blowout, the gas ignited, and after two weeks the rig and platform disappeared beneath the waters.

A jack-up sank after the seabed collapsed under one of its three legs. The rig sank while being positioned for drilling operations in approximately 40 meters of water. Some 103 workers were onboard the rig when it suddenly tilted, causing the rig to take on water and capsize. One crew member went missing and six others received minor injuries.

[ Property Damage $182 Million. Estimated Current Value $197 Million ]

Image credit: SAIPEM

A fire broke out at Algeria’s main liquefied natural gas (LNG) complex in Arzew’s petrochemical hub. The fire was preceded by two explosions that were reported to shake industrial and residential buildings kilometers away. Many people initially took the blasts for an earthquake, because of their intensity. Four people were reportedly injured in the incident.

Leak from a container of hydrochloric acid when being moved. Firefighters deposited a neutralizing agent on the ground.

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

Several main roads closed after a tanker carrying potentially hazardous chemicals spilled some of its load.

Proximate causes:
• Improperly prepared equipment
• Inadequate engineering/design
• Improper handling of materials (the chemical had leaked from the tanks which were not properly secured)

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

A single-tank car carrying 24,000 gallons of acrylonitrile, derailed and caught on fire. After burning for hours, the fire was extinguished. Thousands evacuated

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

On Tuesday 3 July 1883 the steam coaster Daphne was launched from the Linthouse Shipyard of Alexander Stephen & Sons. The engine had been installed prior to launch but the boilers had not, although an opening was left on deck so that they could be fitted later at another quay further upriver. As was often the case the management were under pressure to complete the contract on schedule and as a result around 200 of the workforce, many of them just boys, had remained on board during the launch so that they could continue work as the vessel was towed to the fitting-out berth.

After a brief ceremony the iron ship slipped into the river and was brought to a standstill by the action of the drag chains. The small crowd assembled on the bank watched in horror as, after a few seconds, the Daphne heeled to port, recovered momentarily then rolled over completely. Despite frantic efforts only about 70 people were saved and it soon became clear that a total of 124 men and boys had lost their lives in the accident.

A subsequent enquiry found that although the hull design was flawed the large amount of personnel and loose equipment on deck had contributed greatly to the capsize as had water flooding into the boiler access hole. Regulations were brought in and procedures were amended to prevent a recurrence. The only money given to the bereaved families came from public donations.

Source: http://clydeside-images.blogspot.com/2010/11/sinking-of-ss-daphne.html | Image credit: Trinity Mirror

An explosion occurred in the final purification column of an ethylene oxide manufacturing plant, resulting in 14 people being injured. The explosion caused several secondary fires on the original units, as well as other units nearby, but all were under control within 30 minutes. The root cause was identified as a rapid overpressurization of the column as a result of decomposition of material within it, although the ignition source was not identified.

[ Property Damage $78 Million. Estimated Current Value $187 Million ]

Image credit: Ineos

An explosion occurred at a chemical plant. Before the explosion, some workers were welding the interior of waste water storage. The blast tore out the upper structure of the storage facility, which subsequently collapsed

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