Texas City refinery explosion

On March 23, 2005, a hydrocarbon vapor cloud ignited and violently exploded at the isomerization process unit of the BP-owned oil refinery in Texas City, Texas. The explosion resulted in the death of 15 workers, 180 injuries and severe damage to the refinery. All the fatalities were contractors working out of temporary buildings located close to the unit to support turnaround activities. Property loss was $200million ($million in ). When including settlements ($2.1 billion), costs of repairs, deferred production, and fines, the explosion is the world's costliest refinery accident.

The explosive vapor cloud came from raffinate liquids overflowing from the top of a blowdown stack. The source of ignition was probably a running vehicle engine. The release of liquid followed the automatic opening of a set of relief valves on a raffinate splitter column caused by overfilling.

Subsequent investigation reports by BP, the U.S. Chemical Safety Board (CSB), and an independent blue-ribbon panel led by James Baker identified numerous technical and organizational failings at the refinery and within corporate BP.

The disaster had widespread consequences on both the company and the industry as a whole. The explosion was the first in a series of accidents (which culminated in the Deepwater Horizon oil spill) that seriously tarnished BP's reputation, especially in the U.S. The refinery was eventually sold as a result, together with other North American assets. In the meantime, the industry took action both through the issuance of new or updated standards and more radical regulatory oversight of refinery activities.

Background

The refinery

The refinery was established in 1933 by Pan American Refining Corporation. Pan American merged with Standard Oil of Indiana in 1954 to form Amoco. BP acquired the refinery as part of its merger with Amoco in 1999. As of January 2005, it was the second largest oil refinery out of 23 in Texas (behind Baytown Refinery), and the fourth overall out of 142 in the United States in terms of operating capacity, which was per stream day.

Baker Panel report

thumb|upright|James A. Baker III

After the March explosion, two more serious process safety incidents occurred at the plant:

On July 28, 2005, a hydrogen gas heat exchanger pipe on the resid hydrotreater unit ruptured, causing a release of hydrogen that erupted into a large jet fire. Fires lasted for about two hours. One person received minor injuries and property damaged amounted to $30 million. The Chemical Safety Board found that a contractor had accidentally swapped a low-alloy steel elbow for a carbon steel pipe elbow during maintenance, causing a failure mode known as high-temperature hydrogen attack (HTHA). The CSB found that BP should have required positive materials verification using an X-ray fluorescence test device and maintained or required the contractor to maintain materials identification using tagging to prevent misplacement of components when reassembling the equipment.

On August 10, 2005, a gasoil hydrotreater developed a leak caused by corrosion and high-temperature sulfidation which resulted in the release of toxic gases including carbon monoxide (CO), hydrogen sulfide (H<sub>2</sub>S), and sulfur dioxide (SO<sub>2</sub>), as well as flammable hydrocarbon vapors. Property damage was around $2 million.

Both accidents required community shelter-in-place alerts. Following these events, on August 17, 2005, the U.S. Chemical Safety and Hazard Investigation Board (CSB) issued an urgent recommendation that BP commission an independent panel to investigate the safety culture and management systems at BP North America. A blue-ribbon panel was assembled, led by former U.S. Secretary of State James A. Baker III. A figure of this stature and curriculum was specifically selected by BP to publicly show to U.S. opinion-makers that the company was eager to learn the lesson and make strides to change.

The Baker Panel differed from BP's and the CSB's investigations in that it was not charged to conduct a root cause investigation. Its scope was broader, focused on BP's corporate safety oversight, corporate safety culture, and its process safety management systems and included all five BP refineries in the United States.

The Baker Panel report was released on January 16, 2007. It cited weak safety culture driven by poor process safety leadership and low employee empowerment as underlying causes of the accidents plaguing the refinery. It also highlighted that despite BP's comprehensive safety management system, this was not sufficiently enforced in their refineries. It also showed that BP's focus in measuring its safety performance relied overwhelmingly on occupational safety indicators to the detriment of process safety performance monitoring. It further stressed that worker fatigue and a system that encouraged overtime had detrimental effects on safe plant operation, and that the company had failed to deal with deficiencies arising from known incidents, risk assessments and audits. Implementation of good engineering practices was also found lacking.

Additionally, the panel interviewed a number of employees, managers and contractors at all five of BP's U.S. refineries. They also created and administered to the refineries a process safety culture survey. They concluded that the Toledo and Texas City plants had the worst process safety culture, while the Cherry Point refinery, located in Birch Bay, Washington, had the best process safety culture. The survey results also showed that managers and white-collar workers generally had a more positive view of the process safety culture at their plants when compared with the viewpoint of blue-collar operators and maintenance technicians.

The report made 10 recommendations on various aspects of process safety (leadership; management system; competence; culture; expectations and accountability; leading and lagging performance indicators; and auditing), as well as on support for line management and industry stewardship.

CSB report

thumb|2020 CSB video animation of the accident|upright=1.35

Given the extent of the disaster the Chemical Safety Board examined both the safety management in the Texas City refinery and the role of the BP Group as well as the role of OSHA as a regulatory body. The CSB investigation team was on site 48 hours after the accident. Some 13 CSB investigators remained onsite for three months. For its investigation, the CSB used a budget of $2.5 million and reviewed more than 30,000 documents, interviewed 370 witnesses, and performed computer modeling and testing. The results of the investigation of the agency were published on March 20, 2007 in a 341-page long report, the most extensive conducted up to that point by the then nine-year-old agency. The report findings were presented on the same day at a public meeting in Texas City.

Design deficiencies

thumb|Diagram of the blowdown stack of the ISOM plant at BP's Texas City refinery|upright=1.35

thumb|upright=0.8|A flare stack, an [[Inherent safety|inherently safer solution to dispose of excess flammable gas]]

One of the key findings of the CSB was that the blowdown system used at the ISOM unit was antiquated and totally inadequate, being located as it was amid the plant and liable to spew unignited heavy vapors down into normally occupied areas. The CSB found that BP had failed to heed or implement multiple warnings and safety recommendations made before the blast regarding the ISOM blowdown system. Among them were:

In 1991, the Amoco refining planning department proposed eliminating blowdown systems that vented to the atmosphere, but funding for this plan was not included in the budget.
In 1992, OSHA issued a citation to Amoco for unsafe design of a similar blowdown system elsewhere in the refinery. However, Amoco successfully persuaded OSHA to drop this citation by relying on the less-stringent requirements in API Recommended Practice 521.
In 1993, the "Amoco Regulatory Cluster Project" proposed eliminating atmospheric blowdown systems, but again, funding was not approved.
Despite Amoco's "Process Safety Standard No. 6", which prohibited new atmospheric blowdown systems and called for the phasing out of existing ones, in 1997, Amoco replaced the 1950s-era blowdown drum/vent stack that served the raffinate splitter tower with an identical system, instead of upgrading to recommended alternatives that were safer.
In 2002, an opportunity to tie the ISOM relief system into the new naphtha desulfurization unit flare system was not taken, due to a US$150,000 incremental cost.
Also in 2002, BP's "Clean Streams Project" proposed converting the blowdown drum to a flare knock-out tank, and routing discharges to a flare. When it was found that a needed relief study of the ISOM system had not been completed due to budget constraints, the Clean Streams decided not to pursue the option.

Between 1994 and 2004, at least eight similar cases occurred in which flammable vapors were emitted by the ISOM blowdown drum/vent stack, of which two resulted in a fire. Yet no corrective action was taken. Furthermore, the blowdown drum was not designed to deal with a vessel overfill. This was not necessarily attributable to Amoco or BP, but rather to a lack of guidance in the API Recommended Practice 521. It is true, however, that in the specific scenario occurred at Texas City, unless the flare knock-out drum (a pressure vessel separating and disposing of excess liquid) were to be designed to cope with liquid overfills from upstream equipment, the mere use of a flare would not have prevented an accident from happening, as CSB investigator Don Holmstrom stated.

Need for updated industry standards

The CSB also issued a recommendation for the American Petroleum Institute (API) and the United Steelworkers (USW, the trade union representing refinery workers) to work together to develop a guideline for understanding, recognizing and dealing with fatigue during shift work, as well as to create performance indicators specific to process safety in the refining and petrochemical industries, since measuring safety purely based on eminently occupational indicators such as lost-time incidents was seen as insufficient in the context of preventing major process accidents. Other recommendations addressed to API were to update Recommended Practice 752 to include guidelines on the safe placement of trailers and temporary buildings in process plants; and to update Recommended Practice 521 Guide for Pressure-Relieving and Depressuring Systems to identify overfilling vessels as a potential hazard for evaluation, to mandate sizing disposal drums for credible worst-case liquid relief scenarios, to warn against the use of atmospheric blowdown drums and stacks attached to piping systems receiving flammable discharges from multiple relief valves, and to urge the use of appropriate inherently safer alternatives such as a flare system.

The CSB judged that the Amoco–BP merger had negatively impacted the ability of the organization to deal with process hazards, because organizational changes occurred without getting assessed in terms of their consequences on safety. Therefore, the Board recommended to OSHA that their Process Safety Management of Highly Hazardous Chemicals regulation, promulgated in 1992 and usually referred to as Process Safety Management (PSM), should include a requirement for management of organizational changes, in addition to the existing rules on equipment and procedural changes. A complementary recommendation was addressed to the Center for Chemical Process Safety, to the effect of developing guidelines on how to perform organizational management of change reviews.

Lack of regulatory oversight

In the United States, the PSM regulation The explosion caused the shutdown of several units at the refinery. In anticipation of Hurricane Rita later in 2005, the entire refinery was shut down. BP then focused on repairing the damage caused by the explosion as well as the hurricane. Process units restart commenced in March 2006. Costs of repairs and deferred production amounted to over $1 billion. The company also paid at least around $2.1 billion in civil settlements. Additionally, BP paid $84.6 million and $27 million in fines to the federal government on OSHA's and the EPA's request, respectively, The disaster is the world's costliest refinery accident.

BP's response and fate of the refinery

thumb|upright=1.5|BP CEOs [[John Browne, Baron Browne of Madingley|John Browne (1995–2007), Tony Hayward (2007–2010) and Bob Dudley (2010–2020)]]

BP initiated a crisis management plan only six hours after the explosion. The following day, a website was set up to publish updates on the accident. Chief Executive Lord John Browne visited the plant on the day after the explosion. In the months after the accident BP tended to put the blame on its operators and supervisors. Victims and union leaders considered this amounted to simple scapegoating. At this point, the company consistently chose not to publicly apologize for the accident. This changed on May 17, 2005, when Ross Pillari, president of BP Products North America, made a public apology, saying "We regret that our mistakes have caused so much suffering. We apologize to those who were harmed and to the Texas City community” and promising "financial support and compensation" to the injured and the families of the dead.

On December 9, BP said they would put in place a budget of $1 billion to be spent over five years to improve safety at their Texas City refinery. They also relocated trailers away from areas where explosions are possible and, more crucially, in March 2006 when an oil pipeline spill was discovered in Prudhoe Bay, Alaska, while multiple investigations into the Texas City explosion were still ongoing. CSB chairman Carolyn Merritt said there were striking similarities between the accidents of Texas City and Prudhoe Bay, including "long delays in implementation, administrative documentation of close-out even though remedial actions were not actually taken, or simple non-compliance" as well as "flawed communication of lessons learned, excessive decentralization of safety functions, and high management turnover." A further serious accident occurred at BP Texas City in 2007, when 143 workers at the refinery claimed that they were injured when they inhaled toxic vapors released at the plant. CEO John Browne resigned in 2007 over unrelated issues, although he did not escape criticism for the lax safety culture and the budget cuts at BP's U.S. refineries. Tony Hayward took over at the helm of the company. Hayward shifted emphasis from Lord Browne's focus on alternative energy, announcing that safety would be the company's "number one priority". By this time, BP had already taken a markedly apologetic stance over recent accidents, especially Texas City, with their executives and technical experts giving presentations about what went wrong and how they were working to prevent that from happening again. However, only three years later, the 2010 Deepwater Horizon explosion and oil spill occurred, causing a very serious impact on the company on a global scale, again stemming from BP's operations in the U.S. As a result, Hayward resigned, and his role was taken over by American-born Bob Dudley. Under Dudley, BP announced in 2011 that it was selling its Texas City refinery as part of its divestment plan to pay for ongoing compensation claims and remedial activities following the Deepwater Horizon disaster. The sale of the refinery was successfully completed at the start of 2013 to Marathon Petroleum Corporation for US$2.5 billion. Marathon already owned the adjoining Galveston Bay Refinery and in 2018 merged the two sites into one refining complex.

Two congressional hearings were held specifically on the Texas City disaster. Among those heard were API, Baker Panel, CCPS, CSB, EPA, and USW representatives, as well as victim relatives. In other congressional hearings dedicated to subsequent BP accidents in the U.S., the Texas City case history was consistently presented within the pattern of degraded safety culture at BP.

Settlements with victims

thumb|Ed Bradley in 2001|upright

BP was named in lawsuits from the victims' families and the wounded. The case of Eva Rowe, a young woman who lost her parents in the explosion, attracted nationwide attention. Rowe said that she would not accept a settlement from BP and would drag the group to justice. Ed Bradley, a well-known American journalist, made her story known in the television magazine 60 Minutes. On November 9, 2006, BP settled the case with Rowe as the last applicant after her lawyers had tried to invite John Browne, BP's chief executive officer at the time of the accident, as witness. The amount of compensation for Eva Rowe remained unknown. BP also paid $32 million to hospitals and education and research institutions nominated by Rowe, including the Mary Kay O'Connor Process Safety Center at Texas A&M University ($12.5 million), the University of Texas Medical Branch in Galveston and its Truman G. Blocker Adult Burn Unit ($12.5 million), the College of the Mainland in Texas City ($5 million), St. Jude Children's Research Hospital in Memphis, Tennessee ($1 million), and the Hornbeck, Louisiana school system ($1 million). Furthermore, BP was forced to publish about seven million pages of internal documents, including the Telos and Bonse reports. Rowe would later participate in one of the congressional hearings held over the accident.

As of September 2007, BP had settled at least 1,350 of around 3,000 lawsuits related to the accident. By February 2008, about 4,000 claims were filed, of which half had settled, for a total exceeding $1.6 billion. BP also said that they had set aside a further $525 million for other claims.

Criminal prosecution

thumb|Judge Rosenthal in 2014

On February 4, 2008, U.S. district judge Lee Rosenthal heard arguments regarding BP's offer to plead guilty to a federal environmental crime for two violations of the Clean Air Act (CAA) with a $50 million fine. At the hearing, blast victims and their relatives objected to the plea, calling the proposed fine "trivial". However, the plea was eventually agreed, together with a three-year probation period for BP.

Fines

In September 2005, the Occupational Safety and Health Administration, which in the CSB report would be found lacking in oversight and competency, gave BP a record $21 million fine for committing 301 violations of the Process Safety Management rule. In October 2009, OSHA imposed a fine of $87 million, which shattered its 2005 record, after claiming that BP had failed to implement safety improvements following the disaster and noting that four further fatal accidents occurred in the refinery since the previous fine. In its new report, OSHA cited 709 safety violations. BP announced that it would challenge the fine. On August 12, 2010, BP announced that it had agreed to pay $50.6 million of the 2009 fine, while continuing to contest the remaining $30.7 million (the fine had been reduced by $6.1 million between when it was levied and when BP paid the first part). In July 2012 OSHA and BP agreed that the outstanding $30.7 million would be reduced to $13 million, which BP paid. Most of the violations were not directly related to the explosion but rather to other events, like the two later accidents in 2005. A first fine of $12 million was imposed on BP by the EPA in February 2009. This settlement also included BP's agreement to spend nearly $170 million to improve its environmental performance, with over $150 million dedicated to management of benzene emissions and the remainder addressing chlorofluorocarbons and asbestos. In September 2010, the EPA and BP agreed on a settlement of $15 million on additional counts of violation.

At the request of the Texas Commission on Environmental Quality (TCEQ), the Texas Attorney General opened proceedings against BP for violations of the Texas Health and Safety Code and Texas Water Code, including the release of hydrocarbons through the blowdown stack on March 23, 2005, the prolonged release of benzene from a tank damaged in the explosion, which lasted more than 25 days, and tens of other events.

Impact on process safety

The disaster had a notable impact in the domain of process safety. Texas City has become a classic case history used to explain failings in both management and technical barriers in process plants.

The Baker Panel report became well known among process safety engineers, who felt its findings were relevant to other plants and it was important for strengthening process safety awareness in the chemical process industry. This fulfilled the Panel's wish as stated in the report:<blockquote>Although we necessarily direct our report to BP, we intend it for a broader audience. We are under no illusion that deficiencies in process safety culture, management, or corporate oversight are limited to BP. Other companies and their stakeholders can benefit from our work. We urge these companies to regularly and thoroughly evaluate their safety culture, the performance of their process safety management systems, and their corporate safety oversight for possible improvements. We also urge the same companies to review carefully our findings and recommendations for application to their situations.</blockquote>

Analysis of weak implementation of process safety management

The accident has been extensively analyzed in the specialized literature, which highlighted how several elements of process safety management (PSM) were implemented weakly and poorly managed. Observations made on PSM elements as defined in OSHA's rule

Process hazard analysis: the plant hazard and operability analysis (HAZOP) failed to identify the column overfilling scenario and the risk assessment for the placement of temporary buildings was not complete and, for the most part, erroneous.
Operating procedures: Deviations from key procedures like the start-up of the ISOM plant had become routine. Additionally, the same start-up procedure lacked sufficient instructions.
Incident investigation: Learning from past incidents and near misses was impaired by the near absence of internal investigations and the consequent spreading of useful lessons learned. and the refinery was also lacking in some of these:

Process safety culture: This failed at all levels, as mentioned in all investigation reports.
Measurement and metrics: Metrics for safety performance management were focused only on occupational accidents. This contributed to give a distorted picture of the health of safety management, since no performance indicators were used to assess the impact of past and the possibility of future process accidents in connection with critical losses of containment of hazardous materials.
Control of ignition sources also failed, as demonstrated by the laxness in managing vehicle access in close proximity to live hydrocarbon process equipment.
Recommended Practice 753: API issued new guidance on the location of trailers and portable buildings within hazardous process sites. The scope of Recommended Practice 752 was reduced to permanent buildings only starting with the third edition.
Recommended Practice 754: API addressed the need for process safety performance indicators in this new Recommended Practice on Process Safety Performance Indicators for the Refining and Petrochemical Industries. In general, in the wake of Texas City, awareness of the difference between occupational and process safety became more widespread in light of the investigations' findings.
Recommended Practice 755: This new guideline was directed to refineries and petrochemical plants and detailed how to put in place a fatigue risk management system (FRMS). This document includes recommendations for work on rotating shifts, for the maximum acceptable number of overtime hours and the number of days to be worked on without interruption.

The CCPS published an extensive guideline on organizational management of change to address another related recommendation from the CSB report.

OSHA also issued an internal memorandum to address the CSB's recommendation on updating the PSM regulation to include requirements for hazardous process facilities to extend their management-of-change procedures to capture organizational changes. However, the CSB did not deem this initiative sufficient to close the recommendation, which, , was still open.

TV documentaries

The accident has been featured in a number of documentaries:

National Geographic's series Seconds from Disaster, season 3, episode 10 "Texas Oil Explosion", first aired on November 6, 2006.
History Channel's series Modern Marvels, season 12, episode 56 "Engineering Disasters 20", first aired on December 6, 2006.
Science Channel's series Engineering Catastrophes, season 4, episode 4 "Terror in Texas", first aired on July 7, 2021.

Explanatory notes

References

Sources

External links

2005 Houston Chronicle Special Report (archived on March 12, 2008)
Baker Panel homepage (archived on July 26, 2007)
BP America (Texas City) Refinery Explosion at Chemical Safety Board
CSB investigation recommendation status tracker
BP response corporate webpage (archived on April 8, 2005)
Remember the 15 (archived on March 12, 2008) – Memorial site for those lost in the explosion
Texas City Explosion – Webpage managed by Brent Coon & Associates, lead counsel in the litigation following the blast. Hosts a wealth of evidence used in the case.