Animation of Chemical Release at DuPont’s La Porte Facility

Animation of Chemical Release at DuPont’s La Porte Facility

[Music] Narrator: November 15th, 2014. The DuPont facility
in La Porte, Texas. Four workers were killed and three were injured
during a large release of highly toxic methyl mercaptan, within the plant’s
insecticide processing unit. The sequence of events that led to the
incident at DuPont began on Monday, November 10th, when the plant’s Lannate Unit was shut down,
due to a problem with a reactor. Within that unit, methyl mercaptan reacts with
other chemicals to create the insecticide Lannate. By noon on Wednesday, November 12th,
operators attempted to restart the unit. However, the startup was unsuccessful, because
piping within the reaction system was blocked. This blockage was common, following a shutdown,
and was caused by a slurry that formed in the pipes from a reaction
between methyl mercaptan and other chemicals. To clear this slurry, operators
flushed hot water through the blocked piping. By noon on Thursday, November 13th, operators
determined that the initial blockage was cleared. But during the operation to remove the blockage,
a valve was inadvertently left open, that should have prevented hot water from flowing into
other piping, known as the methyl mercaptan feedline. The feedline connected the reactor system
to a methyl mercaptan storage tank. Operators later discovered that approximately 2,000
pounds of water had escaped through the open valve, into the feedline
and back into the tank. And the water, mixed with
methyl mercaptan in the feedline, creating a new blockage
that would cause more problems. Since temperatures in the Houston area
had been consistently cold that week, the water and methyl mercaptan mixture formed a solid
material called a hydrate, which blocked the piping. By Friday, November 14th, DuPont personnel were
aware of the hydrate and a group of Operations management and technical personnel developed
a strategy to address the problem. They decided to run hot water directly on the blocked
piping, by placing hoses under the pipes’ insulation, heating the methyl mercaptan feedline
to above 52 degrees Fahrenheit, enough to transform the solid hydrate
back to liquid methyl mercaptan and water. Along the methyl mercaptan feedline, there were
three locations where it was connected by valves to a vent header or piping intended to
remove excess or unwanted vapor from the process. DuPont personnel used
pressure gauges at those three valves to determine where the blockage was and
what progress they were making to clear it. They also knew that when heated, methyl mercaptan
can expand and would need a safe place to vent, to avoid overpressure
of the feedline. Because the unit was shut down, an additional valve
between the feedline and the reactor system was closed, preventing methyl mercaptan from entering
the reactors while they were not running. As a result, in this configuration, the
only place for liquid methyl mercaptan to potentially flow would be into the
vent header, where it was never meant to be. However, DuPont personnel did not
consider this hazard when forming their strategy. First, operators cleared the blockage from a section of
piping, leading from the methyl mercaptan storage tank to a pump that forces methyl mercaptan
into the reactor system. Then operators began working to clear a
section between the pump and the closest valve. They cracked open the valve and began to
heat the piping, to get rid of the hydrate. This caused some methyl mercaptan liquid to vaporize
and flow through the valve into the vent header. When this occurred, pressure
increased on the nearby gauge. Operators continued this process until the
pressure at the first valve stopped increasing, at which point they determined that the
blockage in that section of piping was cleared. Hoses were then moved to the
next section of the feedline. But as it was nearing the end of the Friday day shift,
the hoses were not turned on at that time. At around 6:00 p.m.,
the night shift came into work. The day shift supervisor verbally briefed the night
supervisor about the strategy developed earlier in the day. The operators turned on the hot water hoses
and continued efforts to clear the blockage. By this time,
the second valve was fully open. By approximately 1:30 a.m., the operators
believed they had succeeded in clearing the piping and attempted to
start up the unit. With the methyl mercaptan pump on, they opened the
valve between the feedline and the reactor system. However, they found methyl mercaptan
was still not flowing to the reactors. The blockage remained and they
once again closed that valve. After the failed startup attempt, the Operations
crew took a break and went to the control room. But the methyl mercaptan pump
was left running. The hot water hoses were
still heating the piping. And the second valve to the
vent header remained open. Unknown to the operators,
at approximately 2:45 a.m., the level in the methyl
mercaptan storage tank began to drop. The CSB concluded that at that time the
hot water removed the remaining hydrate and liquid methyl mercaptan
began to flow through the feedline. The methyl mercaptan fed to the system by
the pump followed the path of least resistance, through the open second valve,
into the vent header. The vent system quickly filled with liquid methyl
mercaptan, where DuPont never expected it to be. The vent system connects the methyl
mercaptan storage tank with process equipment, inside the Lannate
manufacturing building. As liquid flowed into the vent header,
pressure began to build within that system. However, high pressure events
within the vent system were not unusual, due to flawed equipment design that allowed
liquid to accumulate at low points in the system. These events occurred so frequently that DuPont
instructed operators to drain liquid from the vent system daily. After the control room operators separately told
two coworkers about the pressure problem, they each went to the third floor
of the Lannate building. The required response was to
drain the vent system of liquid. Two valves were opened and the unanticipated
liquid methyl mercaptan drained into the building, where it readily vaporized,
filling the room with the highly toxic gas. Although one of the operators was able to make a
distress call, both workers died, unable to escape the building. Four additional operators responded to the
distress call and entered the manufacturing building. Two of them were brothers; they died
together on the third floor of the Lannate building. The two other
responding operators survived. In total, four workers were
killed during the release. The release continued for
another hour and a half, before emergency responders with proper protective
gear were able to enter the building and close the valves. DuPont estimated that approximately 24,000
pounds of toxic methyl mercaptan was released.

David Anderson

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100 thoughts on “Animation of Chemical Release at DuPont’s La Porte Facility

  1. Matthew Trzcinski says:

    Really? The odorant was the culprit? There's no winning in some cases.

  2. tam arinds says:

    Music in the background is GREAT

  3. MrPLC999 says:

    Here you have more mickey mouse amateurs dreaming up ad hoc processes to deal with extremely dangerous substances without anyone monitoring or analyzing the overall problem. My God, what incompetence!

  4. burdizdawurd1516 says:

    This incident was quite complex, but the operators did better that 95% of the other CSB videos: they identified the problem, and accumulating issues, and tried to resolve them. It only took a few mistakes for this accident to happen.

  5. BigNick says:

    What an absolute cluster fuck

  6. Abdul Salim says:

    all these nasty chemicals always used for fertilisers! Ends up on our food! Not good!

  7. Dylan Frost says:

    I've been watching quite a few of your videos and it seems du pont are a common topic

  8. J J Hernandez says:

    Very sad accident, I remember hearing about a few year back.

  9. Sleepershark88 says:

    So happy to work as an operator! Trust no pipe!

  10. Charles Thomas says:

    I had a friend working there as a technical staff member. After the accident they began work on corrective actions but DuPont decided to shut it down. They came into work one day and were laid off with basically no warning, but hey, economics always rule.
    A few things not really mentioned in this video was fatigue and pressure from leaders to get the unit up and making pounds. It is very easy to lose situational awareness when many things are not going as planned. Add in fatigue, which is a major factor affecting shift workers.
    One question that should have been raised is what was the composition of the fluids that were routinely drained from the vent header prior to this tragedy. Did it have a history of having methyl mercaptan in it? If not, the operators could have become conditioned to not expecting that concentration of the chemical.

  11. JimboBillyBob Justice says:

    I have learned so much about the the processes needed to make stuff from this channel……I love learning how stuff is made..then I also like to know what happens when you FUBAR a process that can kill people

    My top 2 Subscriptions on You-Tube are "How it's made" and "USCSB"

  12. John Doe says:

    Music not wanted

  13. Nataku says:

    Incredible videos

  14. piyush kumar says:

    Sir make a video on Bhopal gas tragedy.

  15. thomas sindicich says:


  16. gumm1wurm says:

    I remember when this happened you could smell it like 30 miles away

  17. mike Wolfe says:

    Drink every time he says methyl mercaptan

  18. J Ewert says:

    DuPont seems to be a common place to get killers while working.

  19. mastershake42019 says:

    Narrator is a boss.

  20. S c says:

    Oh captain Mercaptain!

  21. Odin Valknir says:

    I was working at another plant nearby this one when this all happened.

  22. Josh says:

    Love the music

  23. Able Fox says:

    How is it not standard practice for employees to carry respirator or emergency SCBA equipment ON THEIR PERSON when working with highly toxic materials? It is just common sense, especially in confined spaces and with such huge quantities or material.

  24. r0ckt3hc4sb4h says:

    I should be asleep but I'm on CSB binge.

  25. EA says:

    Great and valuable information to safe lives and just 52k subscribers , any other channel of somebody talking trash or doing stupid things gets millions of subscribers, that is sad…!!!! What is wrong with this world..??

  26. Wilson Olivier Gazer says:

    Your channels are informative even I'm not studying in your respective fields. Good Job!

  27. Mr MEMé says:

    Fart Gass

  28. Dick Fitswell says:

    I work in plants/refineries and Ive always hated shift change. I think any job started must be finished by the shift that started it. Meaning- No handing off of jobs. That would cut incidents in half.
    I was working around this DuPont the year this happened and I cant remember hearing about this…

  29. TheWingedPotato says:

    Yarr matey! What be that foul stench?
    Tis a bit of Methyl M'Captain!

  30. Hippity hoppity your child Is OUR property says:

    You know for a video for safety that’s some good music


    damn brothers dying together, I couldnt work there again

  32. 1bad540i says:

    What is with the lack of remote control valves at DuPont? What is this the 1950's…?

  33. rotaryskratch says:

    I'm really tired of people criticizing corporations for being greedy and overlooking safety/maintenance issues. Profit is far more important than the lives of disposable middle/lower class workers. In the event that something goes terribly wrong, there is always someone else to blame, and paying out settlements costs less in the long run. This way, CEOs and Executives can afford much needed Ferraris, Lamborghinis, summer homes, vacation homes, high dollar hookers and mistresses, and lengthy vacations. Not to mention any gambling or drug addictions they may have. You commoners need to just stfu and do what your masters command without questioning it. You're lucky to have jobs at all, you ungrateful sons-of-bitches.

  34. NECKMINUTE 007 says:

    That's so sad and unfair to people who just want to work

  35. parminder singh says:

    Two fucker died 😁😁😁😁 thats great 2 new jobs created

  36. Mark Hesse says:

    1:28 main error that led to the accident was leaving open the valve to the feedline

  37. Snapper says:

    Why don't they wear gas masks at all times when they do maintenance work? As like a procedure or something…

  38. John Breunig says:

    Read the story,,, The Lawyer That Became dupont’s Worst Nightmare.

  39. J3v16-17 says:

    Do us all a favor and remember that background music should never become so loud that it becomes a distraction…

  40. Syclone0044 says:

    5:23 wow! Look at the detail and accuracy on that white railroad tank car! I'm a model railroader and I'm telling you they've captured everything, the air hoses, the grab iron ladder rungs, the curvature of the coupler lift bar, the air brake reservoir cylinder. I can't believe they can achieve this level of detail for a brief background object!

  41. LastAvailableAlias says:

    Who left the valve open between the reactor vessel and the feed line in the first place?

  42. Mr Briceno says:

    Wow unbelievable you come work your shift at night and nobody tells you that there is a malfunction in the system that can potentially kill hundreds of people… what A surprise…

  43. Kevin Tate says:

    This is a prime example of using some heat tracing on those lines. The vent lines could all have tied in together through out the plant site. I saw a comment about it getting to a scrubber. I am sure there was a scrubber but it will flow the least path of resistance. They had pressure gauges on the lines maybe some thermal units as well may have helped.

  44. Margaret Cooper says:

    I find these animations fascinating, and easy to understand for a non scientist.

  45. Tumblevveed says:

    Whoever makes the animation for these videos does an outstanding job. And the narrator makes it very suspenseful.

  46. LuBu4u says:

    You should do these for people. "LuBu4u has a heart and circulation system like everyone else, but after years of negelect he has let his arties become clogged. As pressure began to build within the system, it began to break down the interal equipment. The nueral system attempted to make on the fly corrections but it was too late. LuBu4u had succumbed to cardiac arrest, and organs began to shut down. He had succumb to a heart attack. Only one worker died."

  47. Red Rooster says:

    Figures, gotta go home right? Gotta take your lunch break. Shoddy all around. Not surprising

  48. John Anders says:

    Really? WTF? Who decides these things? 1. Not having a catalytic oxidizer, Vent gas scrubber, or flare tower, but decides to vent the vent header directly into the building which has no contingency protection from liquid methyl mercaptan? 2. Oversees multiple valves and a pump being left on.
    3. Runs hot water over the methyl mercaptan feed-line which contain a hydrate and methyl mercaptan liquid which vaporizes rapidly when it’s temp goes above 110F.

  49. Nincadalop says:

    If methyl mercaptan is dangerous then why have a connection between its feedline and the vent header where it has to be manually opened?

  50. Sergio Dib says:

    At 6:29 did anyone noticed the buttons that looks like a pioneer djm 900 nxs?

  51. Fonzie Frank says:

    I was a operator that did similar tasks. A Good Field Operator after being Briefed, goes Directly to the Daily Operations Log book, especially on a assignment nightmare like that, check what have " We Been Doing" you get a Idea of our shifts approach to set up the following shift and so on. A Good Field Op Doesn't " Trust No One" you ALL know what each person is dealing with. I respected All my colleagues, but in that business, you're Not Baking Chocolate Chip Cookies. Trust No One, and Nothing. Certain dangerous products Must be Respected. I have worked with products, if you Smell it, it's TO LATE. I am Not Preaching, but you Really have to be Safety Conscious At All Times, I have seen Alot of Preventable Human error. No Excuses to Tired, Bills, it's Not Even my day to Work, etc. Learn what you are dealing with, Never Trust it, Always Respect it. Do Nothing Unsafe for time, or Anyone. It's a Shame things Don't Change Until things like this happen.

  52. Chris Busenkell says:

    Every body that works at that mining company and it's parent/managing company will be drawing their personal water for home use from that aquifer and any others they've contaminated during their sloppy carriers.

  53. Paul Davis says:

    That voice coupled with the background score makes me gravitate towards this video more and more each time I watch it! Great job guys!!

  54. Yolo Swaggins says:

    Methylmercaptan Methylmercaptan Methylmercaptan

  55. Riche Bright says:

    The open valve sound effect is a little annoying.

  56. Joe Chiodi says:

    6:30 dude needs lined up in the back.

  57. Shane Grangrad says:

    The old " it's not my job routine" Kills more people on job sites then any other

  58. Don't, Jimm says:

    So sad. Lives that could have been saved….

  59. 4thegloryofthelord says:

    There should be alarms on certain valves that can cause a dangerous situation if left opened or closed.

  60. Cookies says:

    yall smell something?

  61. Ahmad Afif Isa says:

    Hrmmm what a loss

  62. J P says:

    The smell must have been horrible. Mercaptans are absolutely putrid smelling.

  63. The Dolphin says:

    Yet another head shakingly tragic yet typical case of industrual stupidity. Through these great videos I keep seeing very complex chemical processes in very complex chemical plants having issues which "operators" just do not fully understand in abnormal circumstances to manage. Poor design by "textbook" chemists and engineers failing to imagine and hence document "the average-man" dynamics. So often a case of "the boss wants it back on line by 8am — let's try this".

    And why do staff always fuck up after a change of shift? Because the true situation is not conveyed, because those going home don't give a stuff, and because people "inadvertently" leave valves on or off and "determine" that A should happen when in fact B actually happened.

    I truly hate the chemical industries. Yes, yes, I know they make all sorts of substances "essential to modern life", but the downsides just endlessly keep happening to innocent workers who are cogs in the managerial system of capitalism.

  64. NPC #1997 says:

    I should be jerking off but im on CSB binge

  65. u666sa says:

    I am fascinated by these videos, by the way, Russia here. I especially like those vids where speakers don't appear and story is told, I don't like seeing plain janes pitching corporate mambo jambo none sense. If they were hot I'd change my mind towards it.

  66. justin h says:

    Im on a CSB binge for sure. The excellence of these animations can not be understated

  67. Emory Rogers says:

    All for something to kill bugs. Goddam humans are stupid.

  68. G Funk says:

    Sounds like proper PPE by DuPonte could have saved the lives of the 4 workers that attempted to close the valves.

  69. Rick Sadler says:

    We used to grow food just fine without all these toxic chemicals. What happened

  70. bluediamondminer says:

    Good ol' DuPont………………. how can they still be in the chemical death game?

  71. john Merrick says:

    What’s the background music lol it’s good

  72. alvinpetrovitch13 says:

    This occurred because of unions. Union rules forced mandatory shift times and breaks which caused a communication failure leading to the failure and subsequent loss of life. When you're in the middle of a critical operation, that's not the time to take a break or quit for the day and hand off the task to your relief. The optimal course of action would be the continuance of the troubleshooting cycle until the issue was fully resolved and documented. The only acceptable alternative would be to call the relief team in ahead of schedule and brief them ON SITE with the fouled equipment. This way they could be fully apprised of the situation with the benefit of hands on knowledge of the issue. Unions kill.

  73. Allan Wright says:

    Still could have been prevented alltogether and double checked before restarting operations and also checked again after hot water was run over the piping

  74. dominick253 says:


  75. MsJinkerson says:

    can you say Bhopal

  76. cmfnjaf07 says:

    The brothers were Robert and Gilbert Tisnado. What's sad is Gilbert was bringing a gas mask to his brother and they both died.

  77. Brandon Obaza says:

    When asked to give an assessment on the fatal methyl mercaptan release, authorities simply said, "it stinks."

  78. John Smith says:

    What is that unnecessary, distracting music all about?

  79. gantmj says:

    You know you've watched too many of these when you know there's going to be an expansion issue because of the closed valve.

  80. jacobsladder375 says:

    If you think maintenance is expensive try an accident.

  81. Alma McGill says:

    Hands up if you had no idea what was going on but watched till the end

  82. Tommy Petraglia says:

    Once again the old wisdom is affirmed:

    … nothing good happens after 3 a.m.

  83. J P says:

    The smell must have been horrific everywhere within a 10 mile radius.

  84. Kissalude says:

    The faithful “left a valve open” …

  85. Rabbi Mufti Bischop Lord Kek Prince of Kekistan says:

    anyone else binge watching these CSB investigations?
    makes me wanna apply as a safety or investigation officer

  86. Samsng Device says:

    Isnt that what they use for Raid bug spray?

  87. Brian G. Lee says:

    Good training on what not to do.

  88. SuperAgentman007 says:

    Seems like this accident happened because people with little training and little knowledge of what would happen or in charge of the operation result in any accident next time have people that have experience in this in charge of the operation not inexperienced people and they should’ve had a necessary respirator gas masks and so forth to do that kind of work

  89. relikvija relikvija3 says:

    pipe clusterfuck, no wonder this happens

  90. hillary clinton says:

    why would a floor drain go anywhere or connect to anything but outside?

  91. Naomi Butler-Abisrror says:

    I really enjoy learning about safety in industrial facilities from CSB. The animations are amazing. It's awful the tragedies that have occurred, but I am thankful that we have organizations like the CSB to investigate what went wrong so others, like myself, can learn what to watch out for in our own facilities.

  92. brofenix says:

    My goodness. That was a complicated set of failures. I appreciate the CSB for making a 3D model that seemed quite accurate of the processing units and the animations they made to show the flow of Methyl Mercaptan and Hot Water. This is good to keep in mind, I think a lesson could be learned to evaluate where the flow will relieve too if the liquid expands and flows from the pipe into the vent header. And another lesson would be to have proper drain points or knock out pots, so liquid does not build up in the vent header.

  93. Dumb arse rider says:

    Not my proudest fap.

  94. Miranda Bri says:

    If I can ask a "stupid question", what happens after these releases into the atmosphere? Thanks for these videos

  95. Margaret Cooper says:

    DuPont appears to be involved in many of these accidents.

  96. John Smith says:

    DuPont is featured in several of these videos. And its always poor design and very poor training. Why is DuPont allowed to do business?

  97. Gammareign says:

    The music on this is awesome.

  98. cairo says:

    There should be a TV series about these accidents in a CSI style with actors and full episodes for each accident!.

  99. Mr. Lucky says:

    Dupont loves to kill its own employees

  100. Michael Harris says:

    Dying from any mercaptan has to be a terrible way to go

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