Category → Accidents
Last week, the U.S. Chemical Safety & Hazard Investigation Board released its draft report about a 2010 fire at a Tesoro refinery in Anacortes, Wash., that killed seven workers. The fire occurred when a naphtha heat exchanger ruptured, the report says. The cause of the rupture was high temperature hydrogen attack, which occurs when hydrogen atoms diffuse into carbon steel and react with the carbon to form methane. The methane accumulates in the steel and causes stress and fissures. CSB found that curves established by the American Petroleum Institute to predict high temperature hydrogen attack are inaccurate. “CSB has learned of at least eight recent refinery incidents where HTHA reportedly occurred below the carbon steel Nelson curve,” the report says.
Here’s CSB’s video about the incident:
The CSB found several indications of process safety culture deficiencies at the Tesoro Anacortes Refinery. Refinery management had normalized the occurrences of hazardous conditions, including frequent leaks from the [naphtha hydrotreater unit] heat exchangers, by using steam to mitigate leaks, ineffectively correcting heat exchanger design issues, commonly requiring additional operators during [naphtha hydrotreater unit] heat exchanger startups, and exceeding the staffing levels that procedures specified.
The refinery process safety culture required proof of danger rather than proof of effective safety implementation. For years, technical experts used design data to evaluate the B and E heat exchangers for HTHA susceptibility. Data for actual operating conditions were not readily available, and these technical experts were not required to prove safety effectiveness in reaching their conclusion that the B and E heat exchangers were not susceptible to HTHA damage.
CSB noted several similarities between the Tesoro fire and a Chevron refinery fire in Richmond, Calif., in 2012:
- The Chevron “incident was also the result of a metallurgical failure caused by a well-known damage mechanism called sulfidation corrosion, and Chevron process safety programs failed to identify the hazard before the major incident that endangered the lives of 19 Chevron employees.”
- “Mechanical integrity programs at both Tesoro and Chevron emphasized inspection strategies rather than the use of inherently safer design to control the damage mechanisms that ultimately caused the major process safety incidents.”
- “Rather than performing rigorous analyses of damage mechanisms during the PHA process, both companies simply cited non-specific, judgment-based qualitative safeguards to reduce the risk of damage mechanisms.”
One of the recommendations CSB makes in its Tesoro report is that Washington state implement a “safety case” approach to regulation, in which companies develop their own process safety requirements that are closely overseen by state regulators. The agency made the same recommendation to California in its Chevron report, but that report fell to a divided vote by CSB board members, with board members Beth Rosenberg and Mark Griffon wanting CSB to study regulatory options further. An expected vote on the Tesoro report last week was delayed. What happens from here is an open question. Given criticism of CSB that the agency is taking too long already to complete its investigations, holding reports for further study seems untenable. The federal budget passed last month allotted CSB “$11 million for fiscal 2014, slightly less than previous years and below the Administration’s request of $11.5 million.”
Feb. 5, 2014: Title changed to reflect the fact that although I saw the heat exchangers as a bundle of tubes inside a larger tube, CSB tells me that engineers view the outer structure as a shell, not a tube. In any case, weakened steel from high temperature hydrogen attack was still the problem.
The last couple of weeks have been alarming ones for U.S. industrial accidents. Aside from the chemical spill and subsequent drinking water disaster in West Virginia, “Two people died and 10 were injured Monday morning in Omaha, Nebraska, when the second floor of an animal feed plant collapsed. In Madill, Oklahoma, two workers died when a large industrial furnace exploded at a steel plant Monday afternoon,” Reuters reports.
At this point it’s unclear what prosecutions, if any, will result from the incidents. I recently read a story about the 2008 financial crisis, “Why have no high-level executives been prosecuted?” by U.S. District Judge Jed S. Rakoff. I was struck by the similarities to what’s happened following the BP oil spill in the Gulf of Mexico and Sheharbano (Sheri) Sangji’s death from a lab fire at the University of California, Los Angeles. Prosecutors charged the organizations and some personnel–BP oil rig supervisors for manslaughter and a vice president for obstruction, a UCLA professor for labor code violations–but not top management. From the financial crisis piece:
The final factor I would mention is both the most subtle and the most systemic of the three, and arguably the most important. It is the shift that has occurred, over the past thirty years or more, from focusing on prosecuting high-level individuals to focusing on prosecuting companies and other institutions. It is true that prosecutors have brought criminal charges against companies for well over a hundred years, but until relatively recently, such prosecutions were the exception, and prosecutions of companies without simultaneous prosecutions of their managerial agents were even rarer. …
But if your priority is prosecuting the company, a different scenario takes place. Early in the investigation, you invite in counsel to the company and explain to him or her why you suspect fraud. He or she responds by assuring you that the company wants to cooperate and do the right thing, and to that end the company has hired a former assistant US attorney, now a partner at a respected law firm, to do an internal investigation. The company’s counsel asks you to defer your investigation until the company’s own internal investigation is completed, on the condition that the company will share its results with you. In order to save time and resources, you agree.
Six months later the company’s counsel returns, with a detailed report showing that mistakes were made but that the company is now intent on correcting them. You and the company then agree that the company will enter into a deferred prosecution agreement that couples some immediate fines with the imposition of expensive but internal prophylactic measures. For all practical purposes the case is now over. You are happy because you believe that you have helped prevent future crimes; the company is happy because it has avoided a devastating indictment; and perhaps the happiest of all are the executives, or former executives, who actually committed the underlying misconduct, for they are left untouched.
I suggest that this is not the best way to proceed. Although it is supposedly justified because it prevents future crimes, I suggest that the future deterrent value of successfully prosecuting individuals far outweighs the prophylactic benefits of imposing internal compliance measures that are often little more than window-dressing. Just going after the company is also both technically and morally suspect. It is technically suspect because, under the law, you should not indict or threaten to indict a company unless you can prove beyond a reasonable doubt that some managerial agent of the company committed the alleged crime; and if you can prove that, why not indict the manager? And from a moral standpoint, punishing a company and its many innocent employees and shareholders for the crimes committed by some unprosecuted individuals seems contrary to elementary notions of moral responsibility.
I don’t have enough data to say whether the same pattern holds for prosecutions in occupational health and safety. Certainly some company leaders have been charged–Black Mag gunpowder plant owner Craig Sanborn was convicted last fall of negligent homicide and manslaughter and sentenced to 10-20 years in prison for a 2010 explosion that killed two employees. But who, exactly, gets prosecuted for industrial incidents may be something that warrants closer attention.
University of California, Los Angeles, chemistry professor Patrick Harran had another court status check today. The result is another status check scheduled for March 19. The continued delay in scheduling a trial is due at least in part to the fact that Harran’s attorneys are trying to get the case dismissed through the California Court of Appeal. Harran faces trial on four counts of felony violations of the state labor code relating to the 2009 death of Sheharbano (Sheri) Sangji from injuries sustained in a fire in Harran’s lab.
The Los Angeles County District Attorney’s office filed the charges against Harran and the UC governing body on Dec. 27, 2011. UC settled with the district attorney on July 27, 2012, in exchange for implementing a prescribed safety program and a law scholarship in Sangji’s name. Judge Lisa B. Lench heard testimony in Harran’s preliminary hearing in November and December, 2012, then ruled on April 26, 2013, that there was enough evidence for a trial. On Aug. 26, 2013, Judge George G. Lomeli ruled against additional defense motions to dismiss the case.
On Oct. 24, 2013, Harran’s attorneys filed a “petition for writ of mandate, prohibition, or other appropriate relief” with the California Court of Appeal. The petition covers similar territory as the demurrer motion from last August: The defense argues that UC was the employer and Harran merely a supervisor. California Labor Code section 6425(a) makes it a crime for “Any employer and any employee having direction, management, control, or custody of any employment, place of employment, or of any other employee” to willfully violate an occupational safety or health standard in such a way that causes death or permanent or prolonged impairment of the body of an employee. Nevertheless, Harran’s attorneys write, the specific occupational safety and health regulations Harran is charged with violating reference either employer or no one at all (Title 8, sections 5191(f)(4), 3203(a)(6), 3383(a), and 3383(b)). Other regulations do call out supervisors. From the petition:
In the regulatory scheme, Cal/OSHA thus specifically identifies supervisors as the party legally responsible for certain acts when it deems necessary. In other circumstances, it simply prescribes duties of employers, and leaves to the employer how to divide responsibility for internal implementation of the safety standards. There is no principled justification to disregard the expressed policy preferences of the administrative body charged with promoting workplace safety in this state.
So far, the Court of Appeal has not done anything with the petition. Until it does, the case cannot proceed.
Less than a month after the Chemical Safety & Hazard Investigation Board released its video warning against using methanol for flame test demonstrations, we have this:
A teacher’s chemistry experiment exploded during a demonstration at Beacon High School in Manhattan on Thursday, creating a fireball that burned two 10th graders, one severely, according to Fire Department and school officials. The incident happened about 9 a.m., as Anna Poole, a science teacher at the public school, gave a lesson on how electrons react to different chemicals and give off different colors, according to students and school officials.
Local news reports all say that it was a flame test demo and that the teacher was using methanol, but those stories either don’t attribute the information or use unnamed sources. I contacted the New York City Fire Department, Department of Education, and Special Commissioner of Investigation for the schools, but none of them has been willing to confirm any details of the incident.
But several years of tracking chemistry incidents means that when I hear about students injured in a fire in a high school science class, my first thought is that it was a methanol-based flame test experiment. There is a safer way to do flame tests, by soaking wood sticks in metal salt solutions (chlorides, NOT nitrates) and holding the sticks in a flame. The National Science Teachers Association has detailed instructions here (h/t to @Lewis_lab for the link).
Local coverage of the incident:
- New York Times – Chemistry lab fire injures 2 at a Manhattan high school, School experiment that burned boy was focus of federal warning
- New York Post – Two high school kids burned in lab accident, Safety lapses eyed in Beacon School Chemistry Fire
- New York Daily News – Two Beacon School students injured when science experiment erupts in fireball, Beacon chemistry teacher faulted by safety expert after students burned in experiment
Update: The New York Times had a Jan. 8 story that the fire department has cited the high school for eight code violations involving hazardous chemical storage and safety equipment.
For more discussion, also see Chemjobber: Another accident with the “rainbow flame” experiment, Placeholder for Beacon School incident, FDNY finds code violations
On Monday, the U.S. Chemical Safety & Hazard Investigation Board released its draft report on a 2012 Chevron refinery fire in Richmond, Calif. CSB recommended that the state switch from a “current patchwork of largely reactive and activity-based regulations” to a performance-based system, the agency’s press release says.
CSB released an interim analysis and video of the incident earlier this year. The fire was caused by rupture of a pipe in a crude oil processing unit; the pipe was first identified as corroded in 2002 but was never replaced.
The regulatory approach CSB now recommends is called the “safety case” system and is already used in the United Kingdom, Norway, and Australia. From CSB’s press release:
…the safety case regime requires companies to demonstrate to refinery industry regulators – through a written “safety case report” – how major hazards are to be controlled and risks reduced to “as low as reasonably practicable,” or ALARP. The CSB report notes that the safety case is more than a written document; rather, it represents a fundamental change by shifting the responsibility for continuous reductions in major accident risks from regulators to the company.
To ensure that a facility’s safety goals and programs are accomplished, a safety case report generated by the company is rigorously reviewed, audited, and enforced by highly trained regulatory inspectors, whose technical training and experience are on par with the personnel employed by the companies they oversee, the draft report says.
That will mean that the regulatory agencies involved will also likely have to pay their employees more. A table in the CSB report notes that refinery personnel have an average annual salary of $187,630, while inspectors for county, state, and federal agencies make $96,875-$125,000 (pdf page 81).
CSB is on the report until Jan. 3. The agency will formally adopt or modify the report at a public hearing in Richmond on Jan. 15.
The Associated Press also reported this week that the Environmental Protection Agency “filed a formal notice against Chevron finding 62 violations of federal environmental laws.” The story goes on to say that EPA may “pursue criminal charges or fines if the company fails to address the violations.” So far there seems to be no mention of the notice on EPA’s main or regional websites.
Derek Lowe at In the Pipeline asked his readers this week, “What reagents will you never foget?” The responses are, well, attention-grabbing. Here are a few:
Worked in a stockroom as an undergrad back in the day. One of the faculty gave me a bunch of stuff to “dispose” of & said it was all good to put down the drain.
One solution was a cyanide and another was an acid. I’ll not forget that funny, not together unpleasant smell. Nor the feeling of my knees buckling.
I was decomposing about 500 ml of used Phosphorous Oxychloride by dripping it slowly from a sep funnel into a large beaker of ice.
After talking with my lab partner for a bit, I noticed that the ice had completely melted and the POCl3 was sitting under the water layer un-decomposed.
Forecasting the inevitable eruption, the only thing I could do was close the hood door and pray.
Quite a mess when it went off…
As a metallurgist I generally have a pretty boring view of chemistry. At 900C pretty much all organic chemistry is just a low grade source of carbon. What is memorable is the once every few years that I have to etch an aluminum sample with hydrofluoric acid. No accidents, but it sure inspires care and rigid following of safety protocols.
The other memorable chemistry is mixing up Nital solutions (4% nitric acid in Ethyl Alcohol). A lab partner added alcohol to the nitric acid once, which generated an impressive volume of orange fumes that etched every exposed steel surface in the lab. My memorable encounter is just getting a few drops of nitric acid on my arm, It stings and leaves a stain that takes a couple weeks to fade.
Go check out Derek’s post for more!
The U.S. Chemical Safety & Hazard Investigation Board yesterday released a new video, “After the Rainbow,” that features a student injured in a high school laboratory fire. Calais Weber was 15 years old when her teacher poured methanol on an open flame in front of students at her desk. An explosion and fire ensued, and Weber was burned over 40% of her body.
I haven’t tracked numbers, but in the few years I’ve been following chemical safety news, I feel like I’ve heard of a lot of alcohol fires in schools. I don’t know why people seem to discount the fire hazard of alcohols, but they do.
Weber has this message for students:
While it can seem daunting, it’s perfectly okay to speak up if you’re not feeling safe, to at least question. And if you’re given a piece of information on safety, read it.
“A batch of the protic ionic liquid pyrrolidinium nitrate exploded while drying it under reduced pressure at 110 °C, using a rotary evaporator with an oil bath.”
So says a paper in Green Chemistry
While ionic liquids typically have low vapor pressures and high flash points, that doesn’t mean they’re hazard-free, as the documented experience indicates. KU Leuven chemistry professor Koen Binnemans and colleagues were investigating a series of pyrrolidium ionic liquids with different coordinating groups, one of which was nitrate. The researchers report:
After stirring at room temperature for 4 hours, the remaining pyrrolidine, water and nitric acid were removed on a rotary evaporator under reduced pressure (16 mbar) at 70 °C. Heating of the flask on the rotary evaporator was done by means of a hot silicon oil bath. Not all of the water could be distilled off, and the temperature was increased stepwise to 110 °C. Suddenly an explosion occurred. The glass round-bottom flask was scattered and part of the hot silicon oil in the heating bath was blasted by the shock to the walls and ceiling in the neighborhood of the rotary evaporator. At the same time, a cloud of reddish-brown nitrogen dioxide gas was visible. Luckily, nobody was injured and there was only material damage.
The explosion can be attributed to the strong oxidizing properties of concentrated nitric acid under the anhydrous conditions, resulting in a violent oxidative decomposition of the organic compounds. A search of the literature revealed that mixing of nitric acid with secondary amines like pyrrolidine
has been reported to cause violent reactions. Clark described secondary and tertiary amines as hypergolic with nitric acid.
If you need to dry a nitrate-containing protic ionic liquid, they recommend vacuum freeze-drying rather than heating.
This also seems like an opportune time to remind people of what Prudent Practices has to say about nitric acid generally:
Nitric acid is a strong acid, very corrosive, and decomposes to produce nitrogen oxides. The fumes are very irritating, and inhalation may cause pulmonary edema. Nitric acid is also a powerful oxidant and reacts violently, sometimes explosively [with] reducing agents (e.g., organic compounds) with liberation of toxic nitrogen oxides. Contact with organic matter must be avoided. Extreme caution must be taken when cleaning glassware contaminated with organic solvents or material with nitric acid. Toxic fumes of NOx are generated and explosion may occur.
Please remember to separate nitric acid from organics in both storage and waste.