I work in plants like this very frequently. I can’t get enough of these videos. I find them really intriguing and they shed light on just how dangerous these plants can be.
Their output was decidedly leaner during the previous administration, who reportedly explored shutting them down after appointing Katherine Lemos, as their head.
I spent about 20 years working in refineries, process plants, chemical plants, and pulp mills and I never ceased to be amazed at how poorly many of the plants were maintained and the lack of documentation on changes that had been made in the plants. On the first shutdown I ever worked in a refinery we were given very explicit instructions as to how we were to operate and what to do if things were not as they were supposed to be. Our very first job was to remove some small drain valves on piping assemblies. My partner and I went to the first valve which was on a boiler feed water line. The line was tagged as drained and and safed out ready but when we cracked the valve to see if there was anything in it it began to flow water. We let it run for a couple of minutes but soon it became clear that something was wrong as the flow showed no signs of stopping. We shut the valve down and called for a plant operator who came over to check things out. He cracked the valve as we had and again, after a few minutes, shut it off. He radioed to the control booth and asked for a status on that line and was told that it was drained and ready for repairs. Fortunately the operator smelled a rat and he called the operator for the boiler bank that the line fed and asked for a status. That operator told him that they had needed feed water the night before so it had been put back into service and was still in service. All of the lock out tag out (LOTO) tags were immediately removed and we were told to go on to the next job. A few days later we were going to grind some valves off a process line with a grinder and I noticed that the instrumentation shack immediately beside us was actually sitting over what appeared to be a drainage sump. I stopped my partner and we again called for an operator. The operator came and we showed him what we had found. He had been there a number of years and had never noticed this sump and there was no indication of it in any of the drawings he had seen. He called for a gas sniffer to be brought out to test the sumps contents. The needle went off the scale and we were told not to do anything but wait. Soon a more senior operator came and he had never seen this sump before and another test was run with the same results. That sump was extremely explosive and no work should be being done within 75 feet as per plant rules. It was a big cluster fu*k and soon became bigger when a team of operators was sent out to investigate all of the similar instrumentation shacks within the plant. There were about twenty more in the plant and three others were sitting over sumps, all of which were flammable/explosive. Seems at sometime in the past that an engineer had decided that they could save money by using the curb top of the sumps as shack foundations instead of pouring new slabs. The lesson I learned was don't believe anything that you are told and to check your work area for anything that didn't seem right. These type of over looked problems were fairly common and it was up to you to safe your work area out before proceeding. DO NOT BELIEVE WHAT YOU ARE TOLD! Often it is pure BS. The fact that the second shift operator assumed that the reactor in question was designed for the same pressure as the other three. So my first question would be why was there not a notice posted on the reactors controls pointing this out and why had the software used to control the plant not amended to reflect this fact? In addition, why was the line outlet horizontal and not vertical so it could be safely bled off and who in the engineering department made the decision to run it that way? I can give you the answer to both these questions and it's quite simple. Someone in management decided that it was too costly to make those simple changes so it never got done. Far too many of these plants have a bonus system in place where the manager gets a bonus based on keeping costs down so safety is frequently ignored because those additional steps might cost bonus money. I know of one plant where at the time of construction completion the engineering firm wanted $5,000,000 to provide a complete set of up to date drawings for the plant. The plant owner, a major oil company, refused to pay and decided to operate with what they had. When commissioning and startup was being done, a fire broke out that destroyed that entire operations unit. When they checked the twin unit, they found the same flaw that had promoted the fire and subsequent explosions. During construction, a 42" gas letdown regulator on a 3" gas line had been changed from cast steel to zinc diecast. This regulator was suspended directly above a drainage sump. There was a small valve leaking on a condensate line that had not been properly drained after hydro testing and it had frozen and cracked wide open. The leaking condensate went into the sump and traveled along until it met with a source of ignition in the form of a Herman Nelson heater. When the condensate caught fire, it was traveling fast enough that it kept going along the sump until it terminated directly under the regulator. The heat from the fire was enough to melt the zinc housing and the three inch gas line blew up causing more damage and soon the fire could not be stopped. So by saving a couple of thousand dollars and not having accurate drawings a $50,000,000 unit went up in smoke and had to be completely rebuilt from the ground up. Today those sumps are filled in and the regulators have been replaced with steel units. Bottom line, they saved $5,000,000 so they could spend $50,000,000 to fix the problem. I wonder if the managers and engineers got a bonus that year.......
@@uzlonewolf Insurance on facilities like this is not like your standard home insurance. Under normal circumstances with a claim like this, the amounts paid out by insurance, the owner, the contractor doing startup, the contractor who built the facility, and the engineering firm are negotiated between the parties applicable to determine their liability proportionate to their level of involvement. The engineering firm would be on the hook because they made a change at the clients request for allowing a change that could be considered substandard. If documentation showed that they had fought against the change, they would have paperwork showing they had protested and why along with a signoff from the client to make the change under protest. The building contractor would be on the hook because they had not performed the hydrotest properly and had not drained the line with the cracked valve properly. The contractor doing the startup would be liable because they had not left a firewatch on in the unit while the crew went for their break. The owner would be liable for the deductible (probably 5 - 10 million) and their liability for negligence by making the change in the first place even though the engineer had protested. The insurance company would only pickup what is left over. I doubt very much that insurance covered more than half of the damages.
Are we just being spoiled now? Thanks for another great animation! You guys make the most captivating and interesting safety videos. The work you are doing is important and I appreciate the effort you put into these animations for us.
They don’t make these videos for us, they make them for the company, and osha, and safety boards, they just so happen to post it for the public which is nice
@@K1LL1onaire lmao I would give anything to see a government-animated antifa stick figure huck a rock into this one exact part of a heat exchanger that just happened to be vulnerable because it was rusty because a culture of relaxed standards had set in at the plant after post-2008 layoffs and also one guy took off early but only on that one day
that's what i was thinking, just an overlay that looked like the rest but with a red plate blocking everything above safe operating pressure. just a simple paper, plastic or metal piece placed over the gauge. or if it was just a number readout have the max pressure over or under each readout, with the lower pressure highlighted somehow.
can we all stop and take a moment and think of a comment that hasn't been repeated ad nauseam? just thumb up one of the other hundred comments saying the same thing.
@@dissimulii Can we all agree that people have the same ideas and dont first head into the comments to see if their same comment has been posted previously?
It's a quiet week at work for me (I work in a refinery), but I never waste my working hours so I'm watching some videos frome this great channel to learn something new. Thanks for your videos, they are very well crafted and educational.
_"I never waste my working hours"_ Of course you don't, when asked, we are "always working" or "always busy" 😹 One can never say: "Oh, I'm just relaxing a bit" or "resting my eyes." 😹
Thank you, Chemical Safety Board, for putting this up on the wider Internet for us to learn from. I hope all of us are as diligent as you all are in helping to prevent workplace disasters.
@@letsburn00 Interesting perspective - I’ll have to ponder that. As an ME (later turned EE) who grew up and was educated in a certain era, I’m definitely on Team Metric (“SI”). But, for whatever reason, PSI doesn’t ruffle my feathers. Maybe it’s that the typically whole numbers are easy to discuss. Or, maybe it’s just something that needs to be purged from my brain. For similar reasons, concrete comes in yrd^3, not m^3. Guess I should purge that as well (that’s the easier of the two anyway).
@@a1nelson Yeah, I get that. I have ordered equipment and they send me the Imperial catalogue, which is frustrating. I just can't imagine in PSI, it's simply not something that naturally translates. I was on a recent project which used SCFs and the entire team was confused because every single other product is in regular units. I guess USCSB has to make congress happy as well and congress aren't engineers.
Seems very strange to me that the pressure relief discharges to atmosphere, horizontally no less, right there at the unit. What were they thinking? Shouldn't it have been piped to the flare instead?? They must've known that if it ever popped off it would be releasing flammable and toxic vapor.
That is because the pressure in the flare piping already could be very high, it is discharged horizontally to disperse it locally instead of vertically where it can be carried away by wind and later come down with the rain polluting large areas. There is simply no mystery there if you either do some research or think about it logically.
Best case you rain toxic vapor down on your employees, worst case you're venting towards the flare or hot pipes. That emergency release needs to be moved, and then take a look at why you have a reactor of a lower pressure when everyone is getting confused about those limits.
As excited as I always am for your next posts, I always know they come at a cost and someone has to be the example. I've been integrating these into my safety meetings. Even though most of them do not directly relate to our job functions, the concept and lessons are the same. Great work!
Man, the animation team has gotten really good. I remember how basic some of the earliest videos were. Now look at them. Got swoops through ladders, cross sections, volumetric fire. Great stuff
As soon as the narrator mentioned that the reactor had a lower pressure tolerance than the others, I immediately went "I know where this is going..." Sure enough...
Yeah, normal reaction pressure was 600psi and maybe he read it once somewhere but it just didnt register or he forgot or even misunderstood, and that reactor has worked flawlessly for years so no one has bothered to tell him. It could be the release valve for the flare was sort of responsive to releases, where it would often open just a bit and then heat up and open up more as heated gases went past it. So they think they have opened it to the correct setting but they were just a tiny bit wrong. Maybe he needed to press the button for 3 seconds and only got 2.9 seconds because a coworker came in, or he got another warning or his boss or wife called him.
@@daniellassander The bottom line is that the systems should have been set up to the point where a careless mistake was impossible. So it either comes down to a failure of the company (to properly train its employees, to provide its employees with a reasonable workload, or properly set up adequate redundant safety features/warnings/etc), or the people involved ignored very clear information or actively circumvented safety features (which might also be a fault of pressure from the company). Either way, the emergency vent aiming highly flammable gas at an occupied area is an obvious fault too. (As is, I would argue, not having the emergency vent function as a flare.)
@@IstasPumaNevada I was the security manager for a mid sized aerospace company. Which means that I was also the safety manager. We would come up with safety guidance - that the employees would ignore because 'their way's better/faster and nothing bad has happened yet.' And my boss - the general manager - tended to side with the employees. One day the receptionist called and asked me to shut off the fire alarm - because she would reset it and it would just go off again. Never occurred to her to wonder why the fire alarm kept going off. A truly frustrating experience.
I just got done watching the T2 video, so I thought it was going to be an explosive rupture. I did not expect a horizontally directed pressure relief valve.
USCSB continues to produce some of the most well thought out and designed reviews of hazards or accidents in the industry. And let me say, This was no exception, wow! Continue the excellent work USCSB.
Its always frustrating to think that these excellent & informative presentations (which save lives) always come at high tragic cost. God bless all those adversely affected.
I learned so much from the information openness and quality of accident report/videos. In my country, such accident reports are for internal consumption only, so even others in the same industry cannot learn from them. USCSBs work is far superior to that. Great job USCSB!
The "pressure" graphic that pops in as the narrator mentions pressure and folds to the side to make space is absolutely amazing. Normally the text would be squished, or the full text would never be displayed, or the gauge would take up unnecessary space. It's just… incredible.
Ethylene is a precursor to ethylene oxide (ETO), which is used in sterilization of medical supplies. Also, it is used before as an anesthetic gas, together with cyclopropane. Also, it is the gas that helps fruits go ripe faster.
@@comcfi haha true. Also, to my understanding, (untreated) fruit also generates its own ethylene and that’s why placing fruit in a closed bag allows it to ripen faster. Fruit basically ripen each other.
These USCSB videos are an excellent training tool for all industry professionals and for those who never previously thought about industrial safety and regulations in the industry. It's clear that safety regulations are there for a reason😎
Always love to see these, nobody else does a better job with presentation to help understand what happened and why. Would love to see you guys cover a recent one in Norwood MA where some hvac guys were working on the refrigeration system in a food processing plant, one died one severely injured in bad shape right now sounds like there was a serious failure to communicate between parties and the systems at the plant were lacking in safety measures, fire chief said there were no valves and all the electronics were dead so they had no way of shutting off the leak or recovering the guy they knew was in there until the building had cleared itself out
For april fools you should make a video about a situation where everything went according to plan. Or a potential disaster that was avoided or severely mitigated thanks to proper procedures and equipment.
Or a whole bunch of ominous foreshadowing build up events about operators not reading up on the new procedures and a shift supervisor off work and they all lead to a catastrophic failure in the cafeteria system where the vegan guy got the chicken salad and everyone's cola was all warm and icky 😄
Would be kind of funny to just make a 20 minute video narrating entirely standard and stable startup sequence for a chemical reactor. And we're all on the edge of our seats... Then everyone finished work for the day and went home safely. The end
The Safety Thirds at WTYP have lots of examples for that. Like that tanker truck full of glacial acrylic acid that almost exploded, as mentioned in the 1943 Frankford Junction disaster episode. ruclips.net/video/CJCW-jXF0J4/видео.html
Not necessarily. They're working on a backlog of topics since they were defunded by the Trump administration. Their funding was restored by his successor after his failed coup attempt. So it's not that something new happened; just something that was previously unevaluated.
The heck were these people doing; using the flare for first response pressure control? I get that oftentimes it is necessary, especially in start-up conditions, but it is still inexcusable that the temperature control scheme wasn't utilized. Also, total failure on the board operators to not get out of alarm and allow this to happen, unless the alerts were coded substandardly. Thirdly, it seems to be an odd design that you would have piping with controls that can vent to the flare, yet the PSV vents directly to the atmosphere.
USCSB has shown us many times that the control board stations in these plants are antiquated and subject to alarm fatigue particularly during a startup sequence where there are multiple sensors reading out of range.
The detail and accuracy of this presentation is astonishing. Even the gauge used to illustrate pressure in the reactor intuitively included rounded 100psi markings. Great channel find.
Have worked in power generation and also LNG production (Liquid Natural Gas) as a process technician these excellent video’s certainly show how accidents can occur and how good training for workers is essential. Certainly surprised that the safety discharge outlet was at right angles towards the plant, maybe the idea was to prevent rain water intrusion? Thought it would have been piped to the flare tower to burn off any escaping product. Thankfully the safety valve did its job to prevent an explosion of the pressure vessel however a disaster to the injured workers, hope they made a good recovery.
id imagine water intrusion could be prevented with a flapper or whatever its called, You see them on the pipes of things like big diesel backup gensets and close off the exhaust pipe when its not running and then flaps open just from the flow.
Suddenly purging that amount of gas to the flare stack would probably cause a fireball at the stack. If water intrusion was a concern, a flapper could have been put in place. The horizontal venting might have been to prevent the blowoff from being ignited by the flarestack, resulting in another fireball?
well, good news is the tank didn't explode! that's what i was expecting! I would say that the Emergency valve should also go to a flare to avoid such harmful situations, emissions be damned (because clearly a more dangerous and toxic situation happened anyways) a good idea to prevent this kind of human error (thinking that tank that looks the same as the other 3 ARE the same) the gauges should be more clearly marked, for example they could be the same gauge with an overlay showing max pressure for each tank, this way it can be clear at a glance what the pressure is and also be clear that this one shouldn't go as high as the others.
I assume the vent didn't go to a flare because it's a last ditch method to prevent the tank from exploding. A line out to a flare could have become clogged. If the existing flair was working the valve on the tank would never have opened. It's surprising to me that the scada system didn't force open the flare valve at a point before the final protection on the tank kicked in.
Certainly should be tied to flare. When I seen the pressure rising and the PSV line to atmosphere in the animation I knew exactly what was going to happen. Its pretty standard where I have operated for everything to be designed for all PSVs to go to flare.
Incredible work as always. Process safety is tangentially related to my day job and these videos always give me extra insight into layered safety controls and incident commonalities. Really helps put things in perspective.
This actually reminds me of Texas City. The safety backups (the PSVs) all worked. But they vented to an insanely unsafe location. How on earth can they justify that vent location if operation of the valve is so unsafe.
Just imagine what would have happened if the safety vent went vertical instead of horizontal. 23 people could have been safer. One little change in the design or installation.
@@Last_day_events vertical venting also has issues. They basically collect water very easily and there is a risk that a week hole can't drain properly and the valve discharge end will rust. That said, I'm used to air venting PSVs only being for inserts like CO2 and N2. A flammable vent is madness
Usually vents going to the atmosphere are directed away from the main process area to lower the risk of personnel harm. However, with a flammable vapour like this, piping should have been to a thermal oxidizer or flare for sure.
As a former pressure reactor operator I cannot stress enough how important it is to be aware of your reactors pressure limits. So glad noone was critically injured!!! 🙏🙏🙏
Our company is using this incident as motivation to re-evaluate all our pressure relief systems. It's great to work for a manufacturer who cares about safety. Keep up the good work.
I was worried that during the turnaround the wrong, higher pressure relief valve was installed on the reactor by mistake. Glad that wasn't the case! But why would relief piping for a flammable vapor be designed to vent straight out to atmosphere where other people and equipment are? Why not vent to the flare or blow down drum
....and this is why you tie PSV outlets into your flare header and don't just dump flammable (or toxic, acidic, reactive etc) substances to atmosphere. I had a fuel gas pressure relief valve release pressure in a plant right next to where I had 5 welders laying underneath a compressor welding it down to the pilings. That PSV popped at only 150psi but the area was almost instantly full of natural gas. I had to run around as quickly as I could and kill the ignition on the trucks and welding generators or we very easily could have been trapped by an explosion in a live gas compressor station. All we got from the plant owners/operators was an apology and a weak explanation as to why that PSV did not discharge into the flare system. I found a new place of employment shortly after that.
Ya know... after so many videos with causes directly tied to aging, outdated equipment, it was really nice to hear that this plant had shutdown for upgrades. Just warms my heart, truly. And not from the ignited ethylene vapors. Hoping none of the many injuries were severe, in this case..? Stay safe out there, peeps ♥c(^-^c)
At least at our local Kuraray plant here in Germany, I can say that safety is taken very seriously. There's no year without little tweaks and changes to the way we do things based on constant evaluation. For workers it can be a little annoying sometimes... :)
Good to hear that this accident didn’t result in any fatalities. Injuries are bad, it not as bad as fatalities. It’s also good to hear that at least the safety systems worked, even if it wasn’t the optimal way of dealing with the overpressure. A 3 minute non-fatal fire is always better than a BLEVE.
I had no prior info to this incident and was worried about a reactor failure, the safety valve curve ball kept me engaged bravo for showing how quickly normal ops can go bad.
How Complex Systems Fail, point 3: "Catastrophe requires multiple failures - single point failures are not enough." "...Overt catastrophic failure occurs when small, apparently innocuous failures join to create opportunity for a systemic accident. Each of these small failures is necessary to cause catastrophe but only the combination is sufficient to permit failure." This is illustrated time and time again by the CSB, but this is perhaps the most obvious one. Several failures, both human and mechanical, compounded to injure 23 people.
@@ARockRaider not surprising. Complex systems always have redundancy and safety. Complex systems are also always operating in a degraded state. Nobody specifically caused this incident, but everyone also failed in small ways that, alone, wouldn't have mattered. Was it the environmental regulation not accounting for this specific scenario? The company not buying one extra reactor to go along with the other new ones? The operator not knowing the condensation made the reactor cold, not just the coolant? An improperly greased valve making it easy to think the valve was opened all the way? A design that didn't consider flammable gas being vented? Someone bringing their welding equipment to their job? No. But also yes. Complex systems have complex failures. This is an excellent example of that.
I’m always surprised to learn that complex processes like these are just manually controlled. Especially the less common phases like startup and shutdown.
me to, how hard would it be to just automate things like temperature and pressure control for this system that already has heating and cooling options built into it?
Yes because we humans can adapt to strange situations which machines cant, for example machines dont understand that they cant send high pressure ethylene into the same flare piping from different reactors at the same time. We humans understand that perfectly well. These systems are highly complex and the situations which can arise are even more complex, machines cant figure that out at all and sometimes in nearly identical scenarios there are two opposite right courses of actions. Lets make an example, lets say you are trying to get a liquid with a low boiling point to react with a gas with a high boiling point. You see the pressure rise at an alarming rate, what has happened? It could be that the liquid started to boil because the pressure was too low and now it turns into a gas which reacts much faster with the gas further increasing temperature and pressure. It could be because the reaction just started and it was a faster reaction then expected, it could be that extra gas or liquid has entered the system, or because the reactor vessel has been heated from an outside source. Well now you need to know how the system looked beforehand in order to best say what the right course of action is, simply cutting gas flow could maybe do it unless there is already a buildup of gas in the reactor. It could be cooling. It could be venting. It could be draining the liquid, It could be just letting it be. It could even be increasing the pressure further to reduce the amount of liquid turning into a gas. Like for example through heating, or closing a pressure relief valve or pumping more liquid or gas into the reactor. Machines has no way in hell of figuring this out, we humans can.
@@daniellassander i don't see how you couldn't have a logic system that would figure out what's going wrong as quickly if not more quickly then human operators, better yet the computer doesn't get distracted and doesn't have to worry about shift change. and you can absolutely have simple logic telling systems "only one of these tanks can use the flare at a time" or any other "sorry can't do that" situations. for example, in this situation the computer wouldn't have left the cooling on as long, preventing the entire disaster or it would have seen the continuing over pressure and would have opened the flare valve preventing the more dangerous situation caused by relying on the over pressure valve. both of these were missed because the operator was busy with other things during startup. I would still expect a human watching over the system in case anything was going sideways, mostly there to take over if the computer breaks somehow.
@@daniellassander It isn't just so much about a system that can handle all cases, but at least something that can follow the designed startup curve. Because that would have told them right in the beginning that the amount of product in the reactor prevented that curve from being followed without massive venting. Because that's the startup issue we see again and again---operators know what temp+pressure they want to have after startup, but they have no idea how much cold product has to be in there before startup to safely reach those values.
Because the actual process is highly simplified in these videos, I assume. Looking at our Kuraray interlayer film plant, you could spend hours on explaining the production line and the training for operators is 3 years - after which maybe 1/8th usually gets it right, while others take an additional year or more to reduce waste product and increase throughput. There are too many variables for ordinary programming to be a realistic alternative. Maybe AI could do it, but a system that is prone to do weird shit you cannot predict beforehand is not something we want in industrial processes, at least not yet.
The animation in these videos is beyond awesome!! Uscsb took perfect animation and said "let's take it up to an amazingly high new level", mission accomplished uscsb, mission accomplished!!!!!
I've always loved chemistry, but one day i found the uscsb youtube channel, my love for chemistry grew and now my friends cant wait for me to shut up about some unwanted facts
As a taxpayer, I basically feel like I am a patreon of this amazing and informative channel! We can only wish other parts of the government offered so much public, accessible and informative contributions!
CSB videoes show that corporations will cut every corner, endanger every life, just to save a few dollars. Unionize and make safety part of the contract.
What a horrible design. The PRV should have been connected to the flare system via a knockout drum. There should have been a High High pressure switch that shutdown the reactor and vented the reactor pressure automatically to the flare. Along with automatically closing the valve that enabled steam to be injected into the water jacket. This design verges on criminal negligence.
I love these videos. All info and no artificial drama! The only thing that could make these even better is if official closed captions in English, Spanish, and maybe French were included. That would make them more widely apply to all North Americans. :)
"Hey guys, um, sometimes Reactor 3 just kinda... belches flame at everybody. Keep an eye out for that!" This is why you don't have a "special" device in a set!
Imagine going about your job and you hear the USCSB narrator start describing what you’re doing 😳
Well, I never! I just heard him tell me that I was reading a RUclips comment that would try to control my mind!
this will be the top comment
I’d immediately start running, and take the rest of the week off…
"as one of the employees became self-aware, and started running from the scene"
"The maintenance worker proceeded to drink coffee in the breakroom, leading to a chemical explosion outside that injured 14 and killed 5."
The animations on this channel never disappoint. Being a chemical worker for over 40 years i can appreciate the time and effort put into these videos.
I know nothing about this industry but I love these videos.
I work in plants like this very frequently. I can’t get enough of these videos. I find them really intriguing and they shed light on just how dangerous these plants can be.
@@nickr831 same
Much respect to the chemical workers in the world! It is a tough but necessary job!
I'm a valve mechanic, instrument tech. Love these videos
Holy heck, the USCSB cannot stop posting, I love how informative these always are.
In an ideal world there would be a point where there are no new accidents for them to report
@jackaw1197 thats why I *always* drink on the job... for the content... for the fans.
@@j2kerrigan lol
@@j2kerrigan lmao. Unexpected but absolutely welcome. Drink up good sire!
Their output was decidedly leaner during the previous administration, who reportedly explored shutting them down after appointing Katherine Lemos, as their head.
I spent about 20 years working in refineries, process plants, chemical plants, and pulp mills and I never ceased to be amazed at how poorly many of the plants were maintained and the lack of documentation on changes that had been made in the plants. On the first shutdown I ever worked in a refinery we were given very explicit instructions as to how we were to operate and what to do if things were not as they were supposed to be. Our very first job was to remove some small drain valves on piping assemblies.
My partner and I went to the first valve which was on a boiler feed water line. The line was tagged as drained and and safed out ready but when we cracked the valve to see if there was anything in it it began to flow water. We let it run for a couple of minutes but soon it became clear that something was wrong as the flow showed no signs of stopping. We shut the valve down and called for a plant operator who came over to check things out. He cracked the valve as we had and again, after a few minutes, shut it off. He radioed to the control booth and asked for a status on that line and was told that it was drained and ready for repairs. Fortunately the operator smelled a rat and he called the operator for the boiler bank that the line fed and asked for a status. That operator told him that they had needed feed water the night before so it had been put back into service and was still in service. All of the lock out tag out (LOTO) tags were immediately removed and we were told to go on to the next job.
A few days later we were going to grind some valves off a process line with a grinder and I noticed that the instrumentation shack immediately beside us was actually sitting over what appeared to be a drainage sump. I stopped my partner and we again called for an operator. The operator came and we showed him what we had found. He had been there a number of years and had never noticed this sump and there was no indication of it in any of the drawings he had seen. He called for a gas sniffer to be brought out to test the sumps contents. The needle went off the scale and we were told not to do anything but wait. Soon a more senior operator came and he had never seen this sump before and another test was run with the same results. That sump was extremely explosive and no work should be being done within 75 feet as per plant rules. It was a big cluster fu*k and soon became bigger when a team of operators was sent out to investigate all of the similar instrumentation shacks within the plant. There were about twenty more in the plant and three others were sitting over sumps, all of which were flammable/explosive. Seems at sometime in the past that an engineer had decided that they could save money by using the curb top of the sumps as shack foundations instead of pouring new slabs.
The lesson I learned was don't believe anything that you are told and to check your work area for anything that didn't seem right. These type of over looked problems were fairly common and it was up to you to safe your work area out before proceeding. DO NOT BELIEVE WHAT YOU ARE TOLD! Often it is pure BS.
The fact that the second shift operator assumed that the reactor in question was designed for the same pressure as the other three. So my first question would be why was there not a notice posted on the reactors controls pointing this out and why had the software used to control the plant not amended to reflect this fact? In addition, why was the line outlet horizontal and not vertical so it could be safely bled off and who in the engineering department made the decision to run it that way? I can give you the answer to both these questions and it's quite simple. Someone in management decided that it was too costly to make those simple changes so it never got done. Far too many of these plants have a bonus system in place where the manager gets a bonus based on keeping costs down so safety is frequently ignored because those additional steps might cost bonus money.
I know of one plant where at the time of construction completion the engineering firm wanted $5,000,000 to provide a complete set of up to date drawings for the plant. The plant owner, a major oil company, refused to pay and decided to operate with what they had. When commissioning and startup was being done, a fire broke out that destroyed that entire operations unit. When they checked the twin unit, they found the same flaw that had promoted the fire and subsequent explosions. During construction, a 42" gas letdown regulator on a 3" gas line had been changed from cast steel to zinc diecast. This regulator was suspended directly above a drainage sump. There was a small valve leaking on a condensate line that had not been properly drained after hydro testing and it had frozen and cracked wide open. The leaking condensate went into the sump and traveled along until it met with a source of ignition in the form of a Herman Nelson heater. When the condensate caught fire, it was traveling fast enough that it kept going along the sump until it terminated directly under the regulator. The heat from the fire was enough to melt the zinc housing and the three inch gas line blew up causing more damage and soon the fire could not be stopped. So by saving a couple of thousand dollars and not having accurate drawings a $50,000,000 unit went up in smoke and had to be completely rebuilt from the ground up. Today those sumps are filled in and the regulators have been replaced with steel units. Bottom line, they saved $5,000,000 so they could spend $50,000,000 to fix the problem. I wonder if the managers and engineers got a bonus that year.......
What an interesting set of stories!
thank you for sharing your experience ! too rare these days
The difference is they would have needed to fork out the $5M, whereas it is the insurance company which needs to fork out the $50M.
@@uzlonewolf Insurance on facilities like this is not like your standard home insurance. Under normal circumstances with a claim like this, the amounts paid out by insurance, the owner, the contractor doing startup, the contractor who built the facility, and the engineering firm are negotiated between the parties applicable to determine their liability proportionate to their level of involvement.
The engineering firm would be on the hook because they made a change at the clients request for allowing a change that could be considered substandard. If documentation showed that they had fought against the change, they would have paperwork showing they had protested and why along with a signoff from the client to make the change under protest.
The building contractor would be on the hook because they had not performed the hydrotest properly and had not drained the line with the cracked valve properly.
The contractor doing the startup would be liable because they had not left a firewatch on in the unit while the crew went for their break.
The owner would be liable for the deductible (probably 5 - 10 million) and their liability for negligence by making the change in the first place even though the engineer had protested.
The insurance company would only pickup what is left over. I doubt very much that insurance covered more than half of the damages.
Fantastic insight thank you
The quality of the video, writing, narration, and animation are absolutely perfect.
also the background music to be honest.
@@nicobettio7883 yes! the music sent me into a trance I stopped watching lol
"Perfect" is a good way to put it. I'm always impressed by the production values.
@@formerx it’s almost as though these videos are being funded by the government 🙄
The most critical and dangerous times of a processing unit are always during shutting down and restart procedures.
Meanwhile, at Kuraray... "yeah we can just have one person who's not paying attention do it, that's fine"
And maintenance
yes and there always seems to be a shift change coinciding with it on accidents
@@MichaelFlatman Yea, always blame it on the third shift.
@@MichaelFlatman Agreed!
Are we just being spoiled now?
Thanks for another great animation! You guys make the most captivating and interesting safety videos.
The work you are doing is important and I appreciate the effort you put into these animations for us.
Exactly!
They don’t make these videos for us, they make them for the company, and osha, and safety boards, they just so happen to post it for the public which is nice
Politics has nothing to do with the CSB.
@@K1LL1onaire lmao I would give anything to see a government-animated antifa stick figure huck a rock into this one exact part of a heat exchanger that just happened to be vulnerable because it was rusty because a culture of relaxed standards had set in at the plant after post-2008 layoffs and also one guy took off early but only on that one day
Yeah that opening sequence? The animator is just showing off at this point.
The new operator not knowing the max pressure could've been solved/prevented by just showing the max pressure right on the pressure readout.
that's what i was thinking, just an overlay that looked like the rest but with a red plate blocking everything above safe operating pressure.
just a simple paper, plastic or metal piece placed over the gauge.
or if it was just a number readout have the max pressure over or under each readout, with the lower pressure highlighted somehow.
@@ARockRaider like, x/740PSI
And x in bold blinking when in proximity of 740PSI.
Right? “EXPLOSION HAPPEN HERE” with Big Red Arrow indicator.
@@roippi3985 no why???
They surely would never let it go that high, riiight?
I'd also like to know how it's possible to miss that even though it triggered an overpressure alarm earlier.
Can we all please stop a moment and appreciate the hard work those 3D modellers and animators have to do to give us these insights?? They are amazing
can we all stop and take a moment and think of a comment that hasn't been repeated ad nauseam? just thumb up one of the other hundred comments saying the same thing.
They have really outdone themselves. Getting so real it's scary.
@@dissimulii Can we all agree that people have the same ideas and dont first head into the comments to see if their same comment has been posted previously?
@@dissimulii No, I take too much pleasure in your irritation.
@@dissimulii No, I take too much pleasure in your irritation.
It's a quiet week at work for me (I work in a refinery), but I never waste my working hours so I'm watching some videos frome this great channel to learn something new. Thanks for your videos, they are very well crafted and educational.
"An operator at the refinery was paying too much attention to a video he was watching to realize a warning light was going off"
@@DaniTheDeer "the investigation team stated that USCSB videos are so good that became a source of distraction for operators and enigineers"
_"I never waste my working hours"_ Of course you don't, when asked, we are "always working" or "always busy" 😹
One can never say: "Oh, I'm just relaxing a bit" or "resting my eyes." 😹
"education purposes" right? It's job related 😏
@@DaniTheDeer 😂😂😂
Merry Christmas USCSB! Your work is thoroughly appreciated.
omg my heart 🥰
Thank you, Chemical Safety Board, for putting this up on the wider Internet for us to learn from. I hope all of us are as diligent as you all are in helping to prevent workplace disasters.
This is next level animation! The fly through at the start showing that the entire plant had been modelled is unreal!
0:54 - For those who are using the Metric system,
740 psi = 51 bars or 50.3 atmospheres
1,150 psi = 79.2 bars or 78.2 atmospheres
Thank you
Thanks. I find it so weird to have an engineering video using PSI.
@@letsburn00 Interesting perspective - I’ll have to ponder that. As an ME (later turned EE) who grew up and was educated in a certain era, I’m definitely on Team Metric (“SI”). But, for whatever reason, PSI doesn’t ruffle my feathers. Maybe it’s that the typically whole numbers are easy to discuss. Or, maybe it’s just something that needs to be purged from my brain. For similar reasons, concrete comes in yrd^3, not m^3. Guess I should purge that as well (that’s the easier of the two anyway).
@@a1nelson Yeah, I get that. I have ordered equipment and they send me the Imperial catalogue, which is frustrating. I just can't imagine in PSI, it's simply not something that naturally translates. I was on a recent project which used SCFs and the entire team was confused because every single other product is in regular units.
I guess USCSB has to make congress happy as well and congress aren't engineers.
Further reference: 1 atm = 14.7 psi. I was trained in torr and inches of mercury (in/Hg) along with PSI. I'm very old.
Kudos to whoever did those particle simulations on the fire ignition. looks great
Seems very strange to me that the pressure relief discharges to atmosphere, horizontally no less, right there at the unit. What were they thinking? Shouldn't it have been piped to the flare instead?? They must've known that if it ever popped off it would be releasing flammable and toxic vapor.
That is because the pressure in the flare piping already could be very high, it is discharged horizontally to disperse it locally instead of vertically where it can be carried away by wind and later come down with the rain polluting large areas. There is simply no mystery there if you either do some research or think about it logically.
It could be to mitigate rainwater intrusion and build up in the pipe.
Harbor freight may have only had elbows in stock that day!
Maybe it used to be pointed at an empty area but then they built more around it
Best case you rain toxic vapor down on your employees, worst case you're venting towards the flare or hot pipes. That emergency release needs to be moved, and then take a look at why you have a reactor of a lower pressure when everyone is getting confused about those limits.
As excited as I always am for your next posts, I always know they come at a cost and someone has to be the example.
I've been integrating these into my safety meetings. Even though most of them do not directly relate to our job functions, the concept and lessons are the same. Great work!
Man, the animation team has gotten really good. I remember how basic some of the earliest videos were. Now look at them. Got swoops through ladders, cross sections, volumetric fire. Great stuff
😅 💯 but at what cost?! It's cause they've been busy 🥴💥😭
As soon as the narrator mentioned that the reactor had a lower pressure tolerance than the others, I immediately went "I know where this is going..."
Sure enough...
Yeah, normal reaction pressure was 600psi and maybe he read it once somewhere but it just didnt register or he forgot or even misunderstood, and that reactor has worked flawlessly for years so no one has bothered to tell him.
It could be the release valve for the flare was sort of responsive to releases, where it would often open just a bit and then heat up and open up more as heated gases went past it. So they think they have opened it to the correct setting but they were just a tiny bit wrong. Maybe he needed to press the button for 3 seconds and only got 2.9 seconds because a coworker came in, or he got another warning or his boss or wife called him.
@@daniellassander The bottom line is that the systems should have been set up to the point where a careless mistake was impossible. So it either comes down to a failure of the company (to properly train its employees, to provide its employees with a reasonable workload, or properly set up adequate redundant safety features/warnings/etc), or the people involved ignored very clear information or actively circumvented safety features (which might also be a fault of pressure from the company).
Either way, the emergency vent aiming highly flammable gas at an occupied area is an obvious fault too. (As is, I would argue, not having the emergency vent function as a flare.)
@@IstasPumaNevada I was the security manager for a mid sized aerospace company. Which means that I was also the safety manager. We would come up with safety guidance - that the employees would ignore because 'their way's better/faster and nothing bad has happened yet.' And my boss - the general manager - tended to side with the employees. One day the receptionist called and asked me to shut off the fire alarm - because she would reset it and it would just go off again. Never occurred to her to wonder why the fire alarm kept going off.
A truly frustrating experience.
As soon as I saw that it was posted by CSB I immediately knew where it was going :o
I just got done watching the T2 video, so I thought it was going to be an explosive rupture. I did not expect a horizontally directed pressure relief valve.
USCSB continues to produce some of the most well thought out and designed reviews of hazards or accidents in the industry. And let me say, This was no exception, wow! Continue the excellent work USCSB.
That's why industry via the federal politicians tried to shut them down.
Mad props to the people who model these plants for the videos. Some serious work and detail.
Its always frustrating to think that these excellent & informative presentations (which save lives) always come at high tragic cost.
God bless all those adversely affected.
What?! 2 in 2 months??! Get it, USCBC!
i think they skipped a few steps
US work culture gives them a lot to work with. I imagine they could do weekly videos.
The Clay Shader effect on this really adds a lot to the presentation, dramatic but not overdone camera work as well. Very impressive. Thank you.
The animations and graphics for these videos are getting better and better each time
how to develope animation like this which software used
@@sabersaid665 cinema 4d or blender
I hope the CSB will be involved in investigating what happened on a Norfolk Southern train accident yesterday in East Palestine, Ohio.
It looks like NTSB has the lead on that one www.ntsb.gov/investigations/Pages/RRD23MR005.aspx
Thank you, USCSB! What a great way to start my morning! So excited
I learned so much from the information openness and quality of accident report/videos. In my country, such accident reports are for internal consumption only, so even others in the same industry cannot learn from them. USCSBs work is far superior to that. Great job USCSB!
There's no notification I enjoy getting more than yours. Amazing content all around. Thank you 😊
Of course this is good content
The "pressure" graphic that pops in as the narrator mentions pressure and folds to the side to make space is absolutely amazing. Normally the text would be squished, or the full text would never be displayed, or the gauge would take up unnecessary space. It's just… incredible.
Ethylene is a precursor to ethylene oxide (ETO), which is used in sterilization of medical supplies. Also, it is used before as an anesthetic gas, together with cyclopropane. Also, it is the gas that helps fruits go ripe faster.
Ah yes nothing tastier than Ethylene enhanced fruit
Also involved in the manufacture of conventional antifreeze, C2H4O + H2O → HO−CH2CH2−OH
@@comcfi haha true. Also, to my understanding, (untreated) fruit also generates its own ethylene and that’s why placing fruit in a closed bag allows it to ripen faster. Fruit basically ripen each other.
Also a precursor to Polyethylene... and Polytetrafluorethylene...
So you're saying that the scorched employees at least didn't have to settle for green bananas that day?
These USCSB videos are an excellent training tool for all industry professionals and for those who never previously thought about industrial safety and regulations in the industry. It's clear that safety regulations are there for a reason😎
Always love to see these, nobody else does a better job with presentation to help understand what happened and why. Would love to see you guys cover a recent one in Norwood MA where some hvac guys were working on the refrigeration system in a food processing plant, one died one severely injured in bad shape right now sounds like there was a serious failure to communicate between parties and the systems at the plant were lacking in safety measures, fire chief said there were no valves and all the electronics were dead so they had no way of shutting off the leak or recovering the guy they knew was in there until the building had cleared itself out
excellent, informative, incredible animation. your work saves lives
This channel never misses. These videos are great for someone with no experience in the field, like me. Thank you USCSB for posting these ❤️
Absolutely love and appreciate the time and effort that goes into these videos!
For april fools you should make a video about a situation where everything went according to plan. Or a potential disaster that was avoided or severely mitigated thanks to proper procedures and equipment.
oh a "close call" situation would be so perfect for that! especially if recent maintenance had been done that helped to prevent the disaster!
YES!
Or a whole bunch of ominous foreshadowing build up events about operators not reading up on the new procedures and a shift supervisor off work and they all lead to a catastrophic failure in the cafeteria system where the vegan guy got the chicken salad and everyone's cola was all warm and icky 😄
Would be kind of funny to just make a 20 minute video narrating entirely standard and stable startup sequence for a chemical reactor. And we're all on the edge of our seats...
Then everyone finished work for the day and went home safely. The end
The Safety Thirds at WTYP have lots of examples for that. Like that tanker truck full of glacial acrylic acid that almost exploded, as mentioned in the 1943 Frankford Junction disaster episode.
ruclips.net/video/CJCW-jXF0J4/видео.html
The animations are truly amazing in these videos.
the animator clearly was having fun with this one! and whoever was doing the SFX
@@ARockRaider yeah
It's always amazing when there's new USCSB content, but it also means something horrific happened somewhere :/
same right
Not necessarily. They're working on a backlog of topics since they were defunded by the Trump administration.
Their funding was restored by his successor after his failed coup attempt.
So it's not that something new happened; just something that was previously unevaluated.
New Palestine video
alternatively: it always sucks when something horrific happens somewhere, but at least it means there's new USCSB content :D
I'm not even in the manufacturing sector and I still find these videos fascinating. Love how to-the-point they are
There's defly the "watching a wreck" aspect, but also learning great things to look out for, even if we aren't around them very often.
The heck were these people doing; using the flare for first response pressure control? I get that oftentimes it is necessary, especially in start-up conditions, but it is still inexcusable that the temperature control scheme wasn't utilized. Also, total failure on the board operators to not get out of alarm and allow this to happen, unless the alerts were coded substandardly. Thirdly, it seems to be an odd design that you would have piping with controls that can vent to the flare, yet the PSV vents directly to the atmosphere.
USCSB has shown us many times that the control board stations in these plants are antiquated and subject to alarm fatigue particularly during a startup sequence where there are multiple sensors reading out of range.
@@Shadowvortx It's always frustrated me that people don't consider false positives to be just as severe as false negatives.
I'm not even in this industry, but these videos are hella interesting and there's nothing like it. Thanks, USCSB!
Dude what did we do to deserve so many USCSB videos recently! I'm here for it!
Who ever thought that a channel like this would be so entertaining. Keep up the amazing work!
Very, very good and informative videos! Thank you for producing them. Merry Christmas!
Did you folks investigate the pulp digestor explosion in Maine?
Do you have a good link for further info?
I really hope they do the digester explosion.
I can’t imagine the time put into these animations, amazing work
I hope the USCSB addresses the tragedy going on in East Palestine, OH right now. These companies need to be held accountable.
They probably will, in like 2 years when the investigation is complete. It'll be interesting to know more.
The detail and accuracy of this presentation is astonishing. Even the gauge used to illustrate pressure in the reactor intuitively included rounded 100psi markings. Great channel find.
Have worked in power generation and also LNG production (Liquid Natural Gas) as a process technician these excellent video’s certainly show how accidents can occur and how good training for workers is essential. Certainly surprised that the safety discharge outlet was at right angles towards the plant, maybe the idea was to prevent rain water intrusion? Thought it would have been piped to the flare tower to burn off any escaping product. Thankfully the safety valve did its job to prevent an explosion of the pressure vessel however a disaster to the injured workers, hope they made a good recovery.
id imagine water intrusion could be prevented with a flapper or whatever its called, You see them on the pipes of things like big diesel backup gensets and close off the exhaust pipe when its not running and then flaps open just from the flow.
Suddenly purging that amount of gas to the flare stack would probably cause a fireball at the stack.
If water intrusion was a concern, a flapper could have been put in place. The horizontal venting might have been to prevent the blowoff from being ignited by the flarestack, resulting in another fireball?
@@inucune why not have an igniter at the exit of a vent, effectively making it an emergency flare?
Great job on the design and approval of a horizontal emergency relief valve
Can't wait to watch if and when there is a full investigation video. Thank you USCSB
well, good news is the tank didn't explode! that's what i was expecting!
I would say that the Emergency valve should also go to a flare to avoid such harmful situations, emissions be damned (because clearly a more dangerous and toxic situation happened anyways)
a good idea to prevent this kind of human error (thinking that tank that looks the same as the other 3 ARE the same) the gauges should be more clearly marked,
for example they could be the same gauge with an overlay showing max pressure for each tank, this way it can be clear at a glance what the pressure is and also be clear that this one shouldn't go as high as the others.
Yeah, could have been a lot worse if that safety discharge outlet hadn't released the pressure.
I assume the vent didn't go to a flare because it's a last ditch method to prevent the tank from exploding. A line out to a flare could have become clogged. If the existing flair was working the valve on the tank would never have opened. It's surprising to me that the scada system didn't force open the flare valve at a point before the final protection on the tank kicked in.
Certainly should be tied to flare. When I seen the pressure rising and the PSV line to atmosphere in the animation I knew exactly what was going to happen. Its pretty standard where I have operated for everything to be designed for all PSVs to go to flare.
Or it could just vent vertically, and not into a crown of people for some reason. Sounds like whoever designed the tank was missing a few brain cells
Incredible work as always. Process safety is tangentially related to my day job and these videos always give me extra insight into layered safety controls and incident commonalities. Really helps put things in perspective.
This actually reminds me of Texas City. The safety backups (the PSVs) all worked. But they vented to an insanely unsafe location.
How on earth can they justify that vent location if operation of the valve is so unsafe.
Just imagine what would have happened if the safety vent went vertical instead of horizontal. 23 people could have been safer. One little change in the design or installation.
I was wondering why the PVS didnt vent to the flare system....
@@Last_day_events vertical venting also has issues. They basically collect water very easily and there is a risk that a week hole can't drain properly and the valve discharge end will rust.
That said, I'm used to air venting PSVs only being for inserts like CO2 and N2. A flammable vent is madness
This channel taught me to work in an office and not a refinery or chemical factory.
why on earth was the safety valve pointed horizontally??
Also why didn’t the safety valve release to a flair?
Usually vents going to the atmosphere are directed away from the main process area to lower the risk of personnel harm. However, with a flammable vapour like this, piping should have been to a thermal oxidizer or flare for sure.
As a former pressure reactor operator I cannot stress enough how important it is to be aware of your reactors pressure limits. So glad noone was critically injured!!! 🙏🙏🙏
new uscsb video???????
Thank you for blessing us with knowledge and a wonderfully made video once again uscsb🙏
I learn so much from you
Thank you to everyone involved in making these.
I’m surprised the relief valve was to atmosphere instead of the flare system?
Our company is using this incident as motivation to re-evaluate all our pressure relief systems. It's great to work for a manufacturer who cares about safety. Keep up the good work.
I was worried that during the turnaround the wrong, higher pressure relief valve was installed on the reactor by mistake. Glad that wasn't the case! But why would relief piping for a flammable vapor be designed to vent straight out to atmosphere where other people and equipment are? Why not vent to the flare or blow down drum
I had zero interest in industrial safety until I got hooked on these videos. Absolutely fantastic job!
....and this is why you tie PSV outlets into your flare header and don't just dump flammable (or toxic, acidic, reactive etc) substances to atmosphere.
I had a fuel gas pressure relief valve release pressure in a plant right next to where I had 5 welders laying underneath a compressor welding it down to the pilings. That PSV popped at only 150psi but the area was almost instantly full of natural gas. I had to run around as quickly as I could and kill the ignition on the trucks and welding generators or we very easily could have been trapped by an explosion in a live gas compressor station. All we got from the plant owners/operators was an apology and a weak explanation as to why that PSV did not discharge into the flare system. I found a new place of employment shortly after that.
The graphics are totally topnotch!!! I love the lessons behind this incident.
Why the safety valve vent is not connected to flare tower..
Exactly
you guys are going crazy over there with 3 videos all done in a month! i will take this as an early christmas present from USCSB!
More stellar work by the USCSB and Abbott animation! Love how the flare wasnt discharging enough so the tank made it's own flare.
I have an immense appreciation for these videos.
Another USCSB video? Sign me up!
Happy to! You start at the Pasadena location Monday. Pack your things!
- Kuraray America, Inc
These animations look better than some movies/video games. Thank you for the best safely videos on the internet
Ya know... after so many videos with causes directly tied to aging, outdated equipment, it was really nice to hear that this plant had shutdown for upgrades. Just warms my heart, truly. And not from the ignited ethylene vapors.
Hoping none of the many injuries were severe, in this case..? Stay safe out there, peeps ♥c(^-^c)
At least at our local Kuraray plant here in Germany, I can say that safety is taken very seriously. There's no year without little tweaks and changes to the way we do things based on constant evaluation. For workers it can be a little annoying sometimes... :)
@@grmasdfII Yeah I can imagine. :P
But very refreshing to see safety taken so seriously, at least. ^.^
Really appreciate the videos you create. It helps educate people about why processes are so important.
Good to hear that this accident didn’t result in any fatalities. Injuries are bad, it not as bad as fatalities. It’s also good to hear that at least the safety systems worked, even if it wasn’t the optimal way of dealing with the overpressure. A 3 minute non-fatal fire is always better than a BLEVE.
I wanted to say the same exact thing. After the last couple of videos I expected worse.
I had no prior info to this incident and was worried about a reactor failure, the safety valve curve ball kept me engaged bravo for showing how quickly normal ops can go bad.
How Complex Systems Fail, point 3:
"Catastrophe requires multiple failures - single point failures are not enough."
"...Overt catastrophic failure occurs when small, apparently innocuous failures join to create opportunity for a systemic accident. Each of these small failures is necessary to cause catastrophe but only the combination is sufficient to permit failure."
This is illustrated time and time again by the CSB, but this is perhaps the most obvious one. Several failures, both human and mechanical, compounded to injure 23 people.
based on the poor maintenance if have seen in other videos they are lucky the over pressure valve worked and kept the entire thing form poping.
@@ARockRaider not surprising. Complex systems always have redundancy and safety. Complex systems are also always operating in a degraded state.
Nobody specifically caused this incident, but everyone also failed in small ways that, alone, wouldn't have mattered. Was it the environmental regulation not accounting for this specific scenario? The company not buying one extra reactor to go along with the other new ones? The operator not knowing the condensation made the reactor cold, not just the coolant? An improperly greased valve making it easy to think the valve was opened all the way? A design that didn't consider flammable gas being vented? Someone bringing their welding equipment to their job?
No. But also yes.
Complex systems have complex failures. This is an excellent example of that.
Love the videos/work you guys put in to these videos, greatly appreciated.
I’m always surprised to learn that complex processes like these are just manually controlled. Especially the less common phases like startup and shutdown.
me to, how hard would it be to just automate things like temperature and pressure control for this system that already has heating and cooling options built into it?
Yes because we humans can adapt to strange situations which machines cant, for example machines dont understand that they cant send high pressure ethylene into the same flare piping from different reactors at the same time. We humans understand that perfectly well.
These systems are highly complex and the situations which can arise are even more complex, machines cant figure that out at all and sometimes in nearly identical scenarios there are two opposite right courses of actions. Lets make an example, lets say you are trying to get a liquid with a low boiling point to react with a gas with a high boiling point.
You see the pressure rise at an alarming rate, what has happened? It could be that the liquid started to boil because the pressure was too low and now it turns into a gas which reacts much faster with the gas further increasing temperature and pressure.
It could be because the reaction just started and it was a faster reaction then expected, it could be that extra gas or liquid has entered the system, or because the reactor vessel has been heated from an outside source.
Well now you need to know how the system looked beforehand in order to best say what the right course of action is, simply cutting gas flow could maybe do it unless there is already a buildup of gas in the reactor.
It could be cooling.
It could be venting.
It could be draining the liquid,
It could be just letting it be.
It could even be increasing the pressure further to reduce the amount of liquid turning into a gas. Like for example through heating, or closing a pressure relief valve or pumping more liquid or gas into the reactor.
Machines has no way in hell of figuring this out, we humans can.
@@daniellassander i don't see how you couldn't have a logic system that would figure out what's going wrong as quickly if not more quickly then human operators, better yet the computer doesn't get distracted and doesn't have to worry about shift change.
and you can absolutely have simple logic telling systems "only one of these tanks can use the flare at a time" or any other "sorry can't do that" situations.
for example, in this situation the computer wouldn't have left the cooling on as long, preventing the entire disaster
or it would have seen the continuing over pressure and would have opened the flare valve preventing the more dangerous situation caused by relying on the over pressure valve.
both of these were missed because the operator was busy with other things during startup.
I would still expect a human watching over the system in case anything was going sideways, mostly there to take over if the computer breaks somehow.
@@daniellassander It isn't just so much about a system that can handle all cases, but at least something that can follow the designed startup curve. Because that would have told them right in the beginning that the amount of product in the reactor prevented that curve from being followed without massive venting. Because that's the startup issue we see again and again---operators know what temp+pressure they want to have after startup, but they have no idea how much cold product has to be in there before startup to safely reach those values.
Because the actual process is highly simplified in these videos, I assume.
Looking at our Kuraray interlayer film plant, you could spend hours on explaining the production line and the training for operators is 3 years - after which maybe 1/8th usually gets it right, while others take an additional year or more to reduce waste product and increase throughput.
There are too many variables for ordinary programming to be a realistic alternative. Maybe AI could do it, but a system that is prone to do weird shit you cannot predict beforehand is not something we want in industrial processes, at least not yet.
The animation in these videos is beyond awesome!! Uscsb took perfect animation and said "let's take it up to an amazingly high new level", mission accomplished uscsb, mission accomplished!!!!!
I've always loved chemistry, but one day i found the uscsb youtube channel, my love for chemistry grew and now my friends cant wait for me to shut up about some unwanted facts
Outstanding video as always. While it's sad that people got injured, at least we got to see an emergency pressure relieve system working as intented.
I’d never thought I’d see a video in my hometown 😅
Bruh time to go get screened for cancer
As a taxpayer, I basically feel like I am a patreon of this amazing and informative channel! We can only wish other parts of the government offered so much public, accessible and informative contributions!
Who else waiting for the East Palestine video to drop?
1:48 isn't condensing causing temparature to RAISE instead of being said here to decrease?
CSB videoes show that corporations will cut every corner, endanger every life, just to save a few dollars. Unionize and make safety part of the contract.
another excellent video. we're so lucky that the USB is posting more. thank you!!!!
New USCSB vid!? Yes please!
Seeing a new USCSB video the best surprise that one could ask for! Thank you! 🙏
Anyone else find the narrator weirdly calming
WOW! Another animation in 2 wks? Y'all have been working hard!
What a horrible design. The PRV should have been connected to the flare system via a knockout drum. There should have been a High High pressure switch that shutdown the reactor and vented the reactor pressure automatically to the flare. Along with automatically closing the valve that enabled steam to be injected into the water jacket. This design verges on criminal negligence.
I love these videos. All info and no artificial drama! The only thing that could make these even better is if official closed captions in English, Spanish, and maybe French were included. That would make them more widely apply to all North Americans. :)
Well, at least they didn't exceed their carbon credits by releasing the pressure.
3 uploads in 1 month? Truly a Christmas miracle
"Hey guys, um, sometimes Reactor 3 just kinda... belches flame at everybody. Keep an eye out for that!" This is why you don't have a "special" device in a set!
I love sharing your videos with my students. Thanks for the stellar animation and explanation!
I remember this!! I work by this area
God i love this channel. The analysis is brilliant, and the cgi is inspirational.
ayo new csb just dropped