Transcript
Traci: Welcome to Process Safety with Trish and Traci, the podcast that aims to share insights from past incidents to help avoid future events. This podcast and its transcript can be found at chemicalprocessing.com. I'm Traci Purdum, editor-in-chief of Chemical Processing. And as always, I'm joined by Trish Kerin, the director of the IChemE Safety Centre. Hey Trish, how are you?
Trish: Hey Traci. I'm doing really well today. Thank you.
Traci: Good. I first wanted to thank you for reaching out to me and making sure I was okay and out of harm's way over the recent news of the train derailment of the Norfolk Southern Railway cars in East Palestine, Ohio, which is about 100 miles southeast of me here in Cleveland. This incident happened on Feb. 3, but the fallout is still making news. And new data shows that vinyl chloride made not have been the only hazardous chemical on the train. To mitigate risks, a few days after the train derailment on Feb. 6, crews released the toxic chemicals from five derailed tanker cars that were in danger of exploding and began burning them after warning residents to leave immediately or face the possibility of death. You and I spoke about transporting hazardous chemicals via train in a past podcast episode. I just wanted to get your thoughts and insight on this very current event as it's unfolding.
Trish: Yeah, this is a really, really serious event that we're seeing occur. Depending on what some of the chemicals are, I don't know what some of them are, but certainly, I do have some knowledge of having worked with vinyl chloride for a number of years. A vinyl chloride bleve [a boiling liquid expanding vapor explosion], which is what they were trying to prevent, one would assume, by releasing the pressure in the tanks so that they didn't explode in the fire is quite a significant thing to undertake. And the controlled burning of their chemicals, I have to say I was a bit surprised that that was the path taken. When you're dealing with something like natural gas or LPG, that's a really normal thing to do.
You would combust the chemical or the gas, the liquid so that you don't have a vapor cloud that you could lose in an uncontrolled manner and then have an explosion. But to burn something like vinyl chloride, I felt, was quite interesting. Because when you burn vinyl chloride, it basically forms hydrogen chloride and when hydrogen chloride hits the moisture in the atmosphere, it forms hydrochloric acid. Where actually, in this instance, potentially creating acid rain. There must have certainly been a lot of concerns of needing to do something very significant to prevent the explosion of those tankers, if the path they've taken is to create acid rain over the surrounding areas.
Traci: It almost feels like there wasn't a plan in place. Obviously, you can't have a plan in place for something like this. It's a very fluid, no pun intended, but it's a very fluid situation, but it just feels like they're just making things up as they go. I know it's probably not the case, but it just seems like there was no good process safety plan in place.
Trish: Yeah. It'd be interesting to understand the degree of planning they did have on their emergency response on what they would do with a train derailment and the carriages carrying a substance like vinyl chloride or indeed any of the other hazardous substances that are on there. Do they have a situation where they actually have some incompatible substances on that train, which they might be separated by other chemicals when the train's all in the right order? But when it's derailed, you could have some issues with chemicals coming in contact with each other potentially. So, it would be really interesting to understand the degree of planning they do for an emergency response in this particular instance.
It's not only about the human, protecting the human in this instance as well, that's obviously an incredibly critical part of it, but you also need to make sure you protect the environment here. My understanding is it's quite close to a water catchment that forms a substantial water reserve inflow for quite a large population across the U.S. as well. So, you've got to make sure you don't end up with some of these chemicals in the water supply as well.
Traci: The watershed there feeds into the Mississippi River, so it does hit a large swath of the United States, and that is a big concern. They're noting that wildlife, many fish 3,500 fish have since died from this release. It seems like every day something new comes out. One of the new things I was watching on our local news here is that the railway, Norfolk Southern, was supposed to address residents and decided to pull out of that meeting for fear of their own security and safety. It's just every day something is coming up in the news with this whole incident and it's just very catastrophic.
Trish: Yeah, very concerning. I certainly hope that it can be resolved quickly because some of the long-term effects, not only for the environment but also for human health potentially are quite significant. It's a very concerning event.
Traci: Indeed. Let's switch gears for today's planned topic that we had. It's the five-year anniversary of the earthquake in Komo, Papua New Guinea. This event caused Exxon Mobil to temporarily shut down its gas conditioning plant, situated about five miles from the epicenter. In order to assess damage, officials later confirmed that all of the staff were safe and accounted for, while the administration buildings living quarters and mess hall had sustained some damage. Let's talk briefly about what happened that day. There was no loss of containment, which is fairly surprising with a large earthquake so close to the facility. No?
Trish: Absolutely, and I think it does just go to show how when you apply the correct design standards, taking into account potential seismic activity we can do a good job at mitigating what the potential damage can be. The one thing you can't do is you can't prevent the earthquake happening. When you do have an earthquake that triggers a technological event, that is what we call a Natech incident. A natural hazard triggering technological event. You can't prevent the earthquake, so all you can do is mitigate. In this instance it appears as though their design was an effective mitigation against a potential loss of containment. They obviously had some form of seismic detectors available. They'd obviously designed their pipe work in their facilities to cope with an earthquake and they would've made a determination on the size of earthquake they were coping with as well and designed to that.
Then their shutdown systems, the automated shutdown systems, the moment it started to detect the earthquake occurring, shut down and the plant went into a safe state to leave it in such a state that when the earthquake continued, the equipment did not sustain damage, which I think is a great testament to some really good engineering, I think, that was probably put into that design. But also, that planning of making sure you're very clear on what natural hazards could affect your facility, and designing to deal with them, whether it's earthquake, whether it's flood, whether it's landslide, whatever it is, tsunami, even as we saw in Fukushima, making sure you have the right controls in place to mitigate the incident when it occurs because we can't prevent the natural disaster. That's one of the challenges we have.
Traci: You talk about the facility design and a lot of things that ExxonMobil did. Are there other things in addition to those very top-of-mind things that make sense? Are there other things that go into facility design and how can others attain similar results with the planning of their facilities, if they're planning currently?
Trish: In terms of thinking about just facilities more broadly and not this particular one. When you come to design a facility, you always need to start from the inherently safer design principles. That first principle is can we eliminate this hazard? If we can't eliminate the hazard, then what do we do to try and minimize it or mitigate it in some way, either through attenuation or moderation of the hazard. There's a range of different things, isolation even as well. There's a range of different things that we can do to do better design when we are designing something new, making sure that we have things like appropriate spacing and layout so that an incident in one part of a facility won't cascade to another. Making sure that where necessary, we have potentially appropriate separation walls, may be blast walls, firewalls, those sorts of things so that again, we are keeping things apart from each other that could impact on each other.
Looking at understanding the seismic area that you're in. Also, looking at understanding all the other natural hazards that you've got to consider and thinking about what would happen if that event occurred and how would you actually respond to it. If your emergency response plan is going to be to phone in the local fire brigade in the middle of a natural disaster, you need to go back and rethink your emergency response because the fire brigade aren't coming. The fire brigade are too busy dealing with the community that is also suffering the same incident, if it's something like an earthquake. So, you've got to be prepared to manage your own response in that instance. You've got to make sure that you're prepared for a loss of external communication and a loss of external power as well.
So, ensuring that you've got adequate backup power systems and potentially communication systems as well because you can't rely on the phone system to keep working potentially in an earthquake. These things go down. You might be lucky and still have mobile or cellular phones, that's great. But you also might lose those two depending on where you are if towers go down as part of the incident itself. It's really around understanding what the impacts could be and making sure that you've thought about what you're going to do in each of those instances. In some instances you may say, look, this is just too big a control or a barrier. We can't do this. And make sure you understand, if you're not doing a particular control measure or barrier that you understand why. And you can clearly argue why, because that's an argument you're going to have to have at some point it when the incident does occur.
Traci: Talking about the emergency response and bringing up those points that you... yeah, don't think of those things, you're assuming that the fire department can come and save you, but they are already dealing with what they're dealing with, with the general population. What did ExxonMobil do with their emergency response? Obviously, they got it right too.
Trish: We actually don't have details of specifically how they managed that part of it, but what I can determine from the information I've been able to find on this particular incident is that they had emergency evacuation processes in place for their staff. After the emergency shutdown systems kicked in, they detected the seismic activity and they kicked in to shut the plant down safely and put it in a safe state. They then had the emergency evacuation plans for their staff and they must have been well-rehearsed and well-practiced, I would say, because they worked. Everybody was accounted for and safe. In an earthquake when you're only five miles from the epicenter and it was a fairly decent earthquake as well, then you must have had some pretty good evacuation processes. They must have had a safe haven they could go to ride out the earthquake.
They did suffer building damage. That's not surprising. You're going to have some building damage even in the best designed earthquake zone buildings. Things like if you're in high-rise buildings in an earthquake zone, typically things that will occur is that the glass panels from the high-rise buildings will fall out. So, one of the safest places to be is to stay in the building, not go in the street. Things like that are important to understand and take into account. So I think they got the looking after the people bit right in this, of making sure they were able to be somewhere safe and ride out the earthquake. And they also would've had some other shutdown systems, I imagine, in things like the living quarters and the mess where they probably had natural gas connected for cooking and those sorts of activities.
They didn't have any fires, to my knowledge, in the buildings, which is also quite unusual because typically you can get gas leaks. So they must have had some good shutoff valves there, I would presume. As I said, I don't know these details, but these are some of the sorts of things from understanding what occurred to looking at how they may have prepared for that eventuality. Komo is an area that is prone to earthquake activity. Papua New Guinea does have earthquake activity across its whole island.
Traci: You and I in another previous podcast talked about practicing your emergency response. As you stated, this might have been one of the main factors in making sure everybody was safe and accounted for, as is the practice of those emergency response systems. That brings to mind, and I wanted to dial back a little bit about facility design. We're talking about new facilities, but what about facilities that are not designed for these types of things? Obviously, emergency response is very important to make sure that at least they can mitigate those things. Because as you said, you can't plan for the Natech events, but you can plan for what you can plan for. Do you know where I'm going with this? What do facilities that aren't being currently designed old facilities, what can they do to help themselves?
Trish: The options are somewhat limited at that point in time because some of the things to design for an earthquake are actually fundamentally built into how the foundations are built, for example. You're very limited once you've got a facility built, there's not much you can do to deal with the structures to ensure that they remain earthquake-proof for to some degree. So, you've got that challenge there. It's easier to modify buildings and do things to buildings that can strengthen them and protect the inhabitants in the buildings. But if you've got production plant and it's on existing structures, there's probably not a lot you can do there.
So, the next best thing you can do is look at your emergency shutdown systems and make sure you focus on how can we shut down and de-inventory particular parts of the facility in the event of something going wrong. There are some of the sorts of things that are a lot easier to install when the facility exists because it's different sorts of valves you might need to install, but you then motorize those valves in some way, or even indeed have them air supplied that a loss of air sends them to a safe state. You can do those sorts of things. The structural part is a lot harder when it comes to earthquake though, simply because earthquake-proofing goes right down into the foundations. You've got to start from the very bottom there, unfortunately.
Traci: Absolutely. I guess I was thinking of other facilities not necessarily considering earthquakes, but other events that may happen, hurricanes and flooding and those, and some events where it freezes where you wouldn't expect the freezing temperatures like we saw in Texas, here in the United States. Things that they can do to plan for things out of the ordinary.
Trish: In those sorts of instances, it's around understanding what could a natural disaster be in your area and then looking at how you can ready yourself for that. If it is flood, then you're looking at potential levees around the facility, levee walls. If it's hurricane, it's around strengthening of external walls, potentially. Some of these things can be done and retrofitted to existing facilities. But the key bit is to understand what could your natural disaster be? If you can figure out what your natural disaster could be, and this is where you need to get a little bit creative and not do the, oh, that's unlikely, it's not going to happen and so we'll dismiss it.
When it comes to assessing and working in Natech area, we actually need to assume the incident is going to happen regardless of its frequency or cause because we can't predict some of these things. There are some things we can predict. We can predict every hurricane season there are going to be hurricanes in the Gulf of Mexico. We know that that's how the climate system works there. What we can't predict is where they'll make landfall ahead of time until they start to form as a tropical depression, et cetera, and then generate into the hurricane. If you're anywhere near the Gulf of Mexico, you've got to assume that you can be hit by a hurricane. If you're anywhere that has the ability to suffer extreme low temperatures, you have to assume you could freeze. The Texas one is an interesting one. We don't necessarily think about parts of Texas freezing because it's Texas, it's hot, it shouldn't freeze there.
But I was reminded the other day, as the anniversary of the Columbia Space shuttle has just passed. That then brought up a whole lot of memories and there were documentaries on TV about Challenger Space Shuttle. The day they launched Challenger Space Shuttle, the temperature in Florida was below freezing. So, these places can freeze. You need to have a plan for when the weather forecast says it's going to freeze to do something about it, such as draining of pipe work so that you don't crack the pipe work when the fluid inside expands. You may need to shut down, you may need to de-inventory to deal with some of these things. The colder parts of the United States and Canada, for example, they do winterization, they prepare for it. The southern states, I think, are going to need to start to think about it because we are seeing it happen again and again. We're seeing the climate become more extreme in various different parts of the world at different times.
Traci: Trish, is there anything you want to add on this topic on the anniversary or the train derailment?
Trish: I think the key message here, and we've talked about it a number of times in podcasts, is preparation in an emergency. That's actually what it... We need to have the best controls in place that we can have to prevent the incident happening. That goes without saying. So, preventing the derailment in the first place, as an example, is very, very important. But if it does happen, and particularly in something like rail, sometimes the derailment is not always in the control of the railway, of the train driver, for example.
There could be external factors that occur there, but preventing the incident is critical. But on the other side of the bow tie, if we think about it as a bow tie example, the right-hand side mitigation response planning, how you're going to respond is absolutely critical to reduce the impact that we see. If it had to been a derailment without a fire and without gas leaks, we'd be looking at a very different situation. But the fact that then we had a fire escalate, that then caused over-pressure has created a whole cascading event of consequences. We need to get better at our planning and response to stop that cascading of consequences.
Traci: Once again, you prove to be the champion for Process Safety in helping us prepare for incidents that we can't always plan for. Unfortunate events happen all over the world, and we will be here to discuss and learn from them. Subscribe to this free podcast so you can stay on top of best practices. You can also visit us at chemicalprocessing.com for more tools and resources aimed at helping you run efficient and safe facilities. On behalf of Trish, I'm Traci, and this is Process Safety with Trish and Traci.
Trish: Stay safe.
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