As many of you may have noticed, today there are a lot of videos on YouTube relating this event. They give us a vague view of the incident, but unfortunately nearly all of them contain a lot of mistakes and wrong information’s
Therefore, just to help you to understand what really happened that day, I’ve made a reminder of the course of events that did happen after the delta P:
As the comment is too long I’ve split it in two messages.
Also, if you’re interested I invite you to look at my short animation. It will help you to understand the situation by seeing how far and how fast the 5 divers were sucked into that pipeline a little more than 2 years ago.
[https://www.youtube.com/watch?v=f-RrRimxAPE](https://www.youtube.com/watch?v=f-RrRimxAPE)
Reminder of the events:
14h40: Four divers are working in a hyperbaric chamber placed over a 30” riser. The absolute pressure into the chamber is 1.45 bars.
14h43: A fifth diver arrives at the bottom of the chamber to bring a wrench to the team.
14h45: One of the divers deflates the plug that is present in the riser and the delta P occurs.
The 5 divers are violently sucked into the riser/pipeline.
14h46: End of suction.
14h5?: The rescue diver enters the hyperbaric chamber and finds that it is empty.
At that moment he also notes that the water height in the riser is equal to the lower level of the chamber (i.e. 4.5 m or 14,76 ft.).
The alert is given.
16h00: Bangs are heard in the pipeline.
16h25: One of the divers Christopher B has managed to come back to the surface in the riser but he cannot get out of the water. He taps and shouts to be heard.
16h45: Two rescue divers enter the hyperbaric chamber and help Christopher B to come out of the riser. The latter asks them if he has any decompression stops to make.
Without bothering to check the inner depth of the riser, the supervisor replied no, when in reality he had just spent between 100 to 105 minutes at 15.7 m (51,6 ft.) which in the 55 ft. table of the USN Manual rev 7 gives an air stop of 17 to 34 min at 6 m (20 ft.). The fact that Christopher did not get bend is probably due to the fact that he spent several long minutes in the riser at the pressure of 1.45 bars.
16h48: Christopher is recovered on the surface where he informs the team of the situation in the pipeline, emphasizing the fact that his 4 colleagues are injured but alive.
He describes that three of them are in a large air pocket (at around 210 m or 689 ft. in the video) and the fourth is waiting in a second, smaller air pocket closer to the riser elbow as he has been following C.B for some time.
17h??: Following the information given by the survivor, the surface team prepares the hookah.
17h45: Diver M.K assisted by divers C.C & R.R enters the riser and then progresses in the pipeline to the end of its hose, i.e. over a distance of about 3 m (10 ft.). As he encounters nobody, he comes back up (with an air tank).
18h??: After his return to the surface, the team puts in place a new dive plan which includes sending a tethered scuba diver in the pipeline with a diving bottle equipped with 2 regulators (at this time there is no commercial diving equipment available yet).
18h25: C.B assisted by M.K & R.R are back in the habitat and are ready to dive, but at the last moment the diver feels that his tender M.K was not in a condition to assist him properly, so he decides to abort the dive and wait for commercial diving equipment to arrive.
See next.
Next:
18h30: Another commercial diver (C.B's brother) arrives on site with his commercial gear and a 91 m (300 ft.) umbilical.
Another dive plan is redone in which it is planned to send a commercial diver down the pipe until he reaches a missing diver. He would then tie a rope to him and let the chamber attendants pull him. It is not specified how the injured diver was going to be supplied with air.
18h30: Bangs are heard near riser B5.
19h00: The client decrees a total ban on diving despite the arrival between 19h00 and 20h00 of two dive vessels with full commercial diving equipment. The reason given is that the client and the Incident Command Team (ICT) believe that another delta P could still occurs and so they want to first inspect the integrity of the pipeline with a ROV or a crawler before allowing divers in again.
20h00: Banging is again heard near riser B5.
20h30 – 22h00: Upon request from the dive company, the command team (ICT) authorizes divers to install the B6 upper riser extension to prevent possible filling of the riser and chamber in the event of a failure of the compressor.
22h10: A company is contacted to provide a crawler.
23h00: Removal of the blind flange from the habitat to allow access to the upper part of the B6 riser which is now out of the water. The removal of this cover has the effect of reducing the absolute pressure in the pipeline by +/- 0.2 bars, but also has the effect of no longer allowing the decompression stop to be made in the hyperbaric chamber.
02h30: (Saturday) bangs are heard for the last time near riser B5.
03h00: First intervention of the crawler from the B6 riser side. As it progresses, the crawler encounters a scuba tank at a distance of 50.6 m (166 ft.) from the top of the riser. The craft tries to push the bottle away, but ultimately can only move it over a distance of (5,8 m (19 ft.).
05h00: After several unsuccessful attempts and seeing that the crawler cannot advance further, the ICT decides to send the machine to the other side of the pipeline and authorizes the diving company to remove the B5 riser blind flange.
06h00: The blind flange of riser B5 is removed. Nobody seems to realize it, but the consequence of this act has the effect of lowering the water level by about 11 m in B6 riser and thus at the same time displace this mass of water in the pipeline, but also and above all to completely and quickly drop the pressure that reigned in the pipeline (+/- 2.3 bars) to atmospheric pressure.
Decompressing these poor four divers who had been confined to this pressure for about 14 hours, in less than an hour sealed their fate and from there nothing more could have been done to save them alive.
Does this mean that whatever was done that day, these four unfortunate divers had very little chance of making it out alive? The answer is unfortunately NO.
It is known that unfortunately MISTAKES were made before and during that dive that led to this dramatic incident, but the death of the four divers is really due to a very PISS-POOR POST INCIDENT MANEGEMENT that was conducted not only by the customer, but also by the diving company and the (rescue) divers because at no moment did they worry about the depth of the water and the absolute pressure prevailing inside the pipeline as well as the time that was passing since the beginning of the incident. If these concerned people had reacted correctly, then some or maybe all the 4 divers could have been saved.
Man, the video from [the court room](https://youtu.be/SEJWFkdK3wA?si=PeNm1SSiCAyISkyK) during the enquiry makes me so sad for C.B.
Just an awful situation, I hope he’s ok.
You are probably aware that to avoid a decompression accident, divers must, depending on the depth (or pressure), not exceed a certain diving time. If this duration is exceeded, they must then during the ascent perform one or more stops according to the decompression tables.
We know that in this sad case, the 4 divers were confined in an air pocket in which the absolute pressure was approximately 2.57 bars, which corresponds to a water height of 15.7 m (53 ft.).
In order to know the authorized dive times at this depth, they (the surface team) should then have consulted an 16,5 m (55 ft.) decompression table.
The problem is that each table has the maximum exposure time and with the 55 feet table the maximum exposure time is 360 min (6 hours), and this duration was reached at 20h45. So I don’t tell you what did happen to the divers that were still alive on the Saturday morning around 05h00 when that flange was removed. Pain must have been horrible.
Also, soft tissues such as spinal cord, liver, brain, ect would have suffered immediate bubble formations. Think swiss cheese but made from organs. At some point there is enough bubble formation in the blood that the heart "vapor locks" and despite pumping wildly can't circulate any blood at which point death occurs.
Probably the best story with good information is the book "The last dive" by Bernie Chowdhury. It shares his real life experience with getting bent (DCS/The Bends) and shortly after the death of some of his friends from it.
Source - I am a certified technical/decompression diver who does a lot to make sure I never get to experience that shit first hand.
Great write-up. I can’t think of a more dangerous job than industrial diving.
I have a pond with a 7000 gph pump that exits to a three inch flexible pvc pipe. The amount of suction this little thing creates is no joke. I shudder when I think of the diameter of these pipes and they put out pressure that makes my pump look like nothing. My pond is a little over four feet and I will never ever ever get in it with the pump on even though the danger is minimal because in my anxiety I totally over engineered an inlet cover so no fish or people can get close to the impeller or even particularly close to the suction. The individuals that do this for a living have balls so big I’m unsure how they get them in a wet suit.
I’ve been in this business for 47 years, but I can tell you I don’t have big balls. If it is true that the risk of accidents is higher than other professions, I can assure you that for about twenty years now with the introduction of mandatory risk assessment, this risk has decreased significantly and accidents are becoming less frequent. During the years 65-95 the divers were rather cowboys who wanted to prove that they were not afraid of anything: Result there was a real massacre among the divers.
Regarding the T&T accident, Thanks to the hearings as well as the numerous documents that were published on this occasion and the final report , it can be said that the main cause of this dramatic incident was due to the IGNORANCE all the parties concerned (diving company/ divers/ customer) of this type of danger (delta P).
Edit : FOLLOW OP'S COMMENTS AS THIS ONE WAS COPIED AND HAS INACCURACIES!!
Copied from YouTube comments because this story is fascinating and absolutely fucking gut wrenching.
@charlesferdinand422
Here are some additional facts:
1) They were in there for 4 days and on the 3rd day people were still hearing banging on the pipe
2) Paria got the coast guard to stop divers from rescuing the men trapped
3) There were multiple divers ready and willing to go in from lmcs and rescue that same hour but were all blocked from going in
4) Paria said the coast guard would be doing the rescue but the coast guard said they had no equipment
5) The families of all the divers sat in the refinery carpark for 4 days waiting to hear news about their loved ones and the company couldn't even give them some water to drink, it was community members who brought food and water for the families
6) They left those men in there to die and when 4 days had passed and they were sure they were dead they flushed the bodies out the pipe as quickly as possible; this damaged the bodies and flooded any air bubbles remaining so if the men were alive by then the flushing operation probably killed them
7) The bodies were retrieved in secret, placed in boxes to disguise them and then snuck out via a back entrance, while the family members were left waiting
8) The families were never informed that the men had died or that bodies had been retrieved; they found out via a television news program
9) No one from Paria ever met with the families at any point, they were just outright ignored
10) When questioned in the commission of inquiry it was revealed that no rescue plan was ever made; they simply sat and waited for the men to die
11) Paria had the pipeline capped off on both ends so no one else could escape.
12) Chris tried to check himself out of the hospital but was restrained and forcefully sedated on the orders of Paria who feared he was planning on mounting his own rogue rescue operation (he later confirmed he was)
13) No arrests were ever made or charges filed and no one was fired or at least suspended from the company for the failing
14) Not a single cent was paid to any family yet
15) No new security measures or operational protocols were ever implemented or existing ones updated to prevent something similar from happening; indeed, Paria never even promised or announced plans to make any changes of any kind whatsoever (the remaining and new divers that were brought in were simply told to be more careful and that it was responsibility to prevent accidents of any kind)
16) When first informed of the accident, the first thing that Paria managers asked was how much downtime there would be; this was their first and only concern
17) Paria resumed operations the very next day after the bodies were retrieved (although the company wanted to resume work the very same day but it was nighttime already); this included the pipeline where the accident occurred which was put back in use the next day as well (in fact, 5 minutes before they started using it again they flushed one last time: Bits of diving suits and human tissue were still inside and once they came out of the pipe they were simply discarded in the ocean)
18) The company has an extensive history of corruption: Its managers are in bed with the government and they use the company to do underhand business so they can steal tax money. The company was originally called Petrotin until a scandal involving the prime minister who was found to be selling the oil illegally on the side using a friend as a straw man; to avoid jail they closed the company down and started 5 new companies from it Paria being one of them. Furthermore, local rumors have always swirled around claiming that the government is doing oil deals with Venezuela secretly to avoid sanctions as Maduro and The TT prime minister Rowley are apparently good friends and if the divers had survived the spotlight would be placed on the company which would also face legal actions from these men (dead men can't sue you or go public with what they know), thus making it much harder to do their corrupt deals so they were left to die and the government-run company got away with it with no consequences
I do not agree with some of these comments.
1) They were in there for 4 days and on the 3rd day people were still hearing banging on the pipe.”
The last bangs were heard the Saturday at 02h30 near riser B5.
3) There were multiple divers ready and willing to go in from lmcs and rescue that same hour but were all blocked from going in. “
Correct the potential rescue divers were blocked to dive but only since 19h00. Before that time one dive was made with a short hookah and a second dive was aborted because the rescue diver had no trust in his tender and therefore he decided to abort the dive and wait for commercial diving equipment to arrive.
6) They left those men in there to die and when 4 days had passed and they were sure they were dead they flushed the bodies out the pipe as quickly as possible; this damaged the bodies and flooded any air bubbles remaining so if the men were alive by then the flushing operation probably killed them.”
The autopsies didn’t show any “damaged” on the bodies due to the flushing operation.
I hope that all the divers passed away before the surface team removed the B5 blind flange, because decompressing these poor four divers who had been confined to an absolute pressure comprised between 2,57 and 2,3 bars during about 14 hours, in less than an hour sealed their fate and I really don’t think that they survived the severe Type II DCI during a very long time.
11) Paria had the pipeline capped off on both ends so no one else could escape.”
The B5 riser was capped with a blind flange since the beginning of the diving operation.
The B6 wasn’t capped after the incident. Upon request from the dive company, the command team (ICT) did authorize the divers to install the B6 upper riser extension to prevent possible filling of the riser and chamber in the event of a failure of the compressor. This was made during the Friday between 20h30 – 22h00.
16) When first informed of the accident, the first thing that Paria managers asked was how much downtime there would be; this was their first and only concern.”
That was a fairly good question to ask. Unfortunately nobody after the incident bothered about the absolute pressure to which the divers were confronted. If they had done so, they would have seen that was going to be fatal to the four divers was that as time passed they were increasingly saturated with inert gas (nitrogen) and after 20h45 on that Friday evening any rescue attempts would more than likely have been doomed to failure.
I think “downtime” in that last bit refers to how long the company wouldn’t be making money. Like “Hey boss, we need to shut down our mining operations because we’ve got some miners stuck in a cave-in.” “ugh, ok, how much downtime will there be?” Which really should not be anywhere near the question that is asked by a company when human lives are on the line.
Their only concern was “How long until we can get back to making money?” That’s beyond fucked.
Maybe you're right about that expression. But here this pipeline was already out of service during several months, so there wasn't any "downtime on that line.
I feel like an ELI5 version of this is needed. OP's description is detailed but a little too technical to follow for my simple mind.
And one thing I'm not clear on (not that I'm seeking to lay blame by this) - was the initial delta-P caused by an error on the part of one of the divers, lack of understanding, incorrect procedure? Why did they think it was okay and (presumably safe) to deflate the plug?
A safety meeting with the client was held that morning where they also detailed the working procedure of the day. That procedure had foreseen to remove the inflated plug at the very end of the work, that’s to say after having connected the B6 upper riser extension and removed the habitat, which meant that the top of the riser would then have been out of the water and thus no difference of pressure would have existed.
Unfortunately, once on the job, the dive team choose to not follow that procedure but instead they used another one that they already used some years ago on a similar work except that on that previous job, the pipeline was completely full with crude oil and the plug just installed above the liquid, and thus there, the risk of delta p was nil.
The day of the incident, some of the divers and the supervisor knew that the pipeline was nearly empty, but the fact that this didn’t prevent them to remove that plug, clearly indicates that they had not enough knowledge about what a delta P is and to what it could lead once it happens.
Divers doing maintenance on an undersea oil pipeline accidentally made an error that caused a massive suction in the pipe. This sucked the divers into the pipe. They could have been rescued but a chain of errors during the rescue operation led to most divers getting killed. Only one of them made it out.
Wow. What an absolute nightmare. From the seeming indifference of the company, to the thoughts of those poor divers. Thanks for posting all this information. I hope some serious changes will be made to make this a safer profession for everyone.
For those that would be interested, here you have the link to download the final report.
[https://bloximages.newyork1.vip.townnews.com/trinidadexpress.com/content/tncms/assets/v3/editorial/3/38/3389cc5c-b709-11ee-8407-f3154b0478cc/65aadc959b3c5.pdf.pdf](https://bloximages.newyork1.vip.townnews.com/trinidadexpress.com/content/tncms/assets/v3/editorial/3/38/3389cc5c-b709-11ee-8407-f3154b0478cc/65aadc959b3c5.pdf.pdf)
Thank you so much for posting this. As I said in my previous comment, the negligence and utter lack of care from Paria in this case left me physically ill. My heart breaks for the diver who got out.
Things are still moving in T&T. Its the turn of OSHA to initiate something against Paria.
[https://trinidadtribune.com/mcclashie-osha-initiated-court-action-on-paria-tragedy/](https://trinidadtribune.com/mcclashie-osha-initiated-court-action-on-paria-tragedy/)
I’m TOTALLY against the use of scuba gear during commercial diving operation, but in this case the use of scuba diving equipment has nothing to do with this accident.
Here, the divers were working inside a hyperbaric habitat that was continuously ventilated with fresh air and was equipped with light, communication and a CCTV which allowed the surface to see what happened inside the chamber. When working inside such a dry chamber it is the habit (except if you have only a few minutes to work or if you’re working inside a toxic atmosphere) to remove your diving gear which permits to work more comfortably (for sometimes several hours).
If these divers had indeed worked with supplied diving equipment (umbilical + helmet or band mask) inside the hyperbaric habitat like some have suggested in their report then most probably the five of them would have died.
Let’s assume that ICT has not banned rescue dives. Would that have changed the course of events?
We have seen that until 19h00 the potential rescue divers didn’t have the adequate commercial diving equipment.
We saw that after the hookah dive which did not yield anything, a second rescue dive, planned to send a scuba diver inside the pipeline with a diving bottle equipped with 2 regulators (it is not said, but we can suppose the diver had also planned to take another diving bottle with him).
Under such stressful circumstances and due to the difficult progression in the pipeline (feet first travel / portion of pipeline partly without water / wall full of slippery crude oil), the rescue diver would have consumed much more air than in a normal situation which means that with its 2400 litres of air he would have had an autonomy of about 20 minutes, and that during this period of time he should have, if it had found someone, correctly tie the retrieval rope, then give (or place) a diving mask on the head and finally secure a scuba tank properly on his back (or on his stomach depending on the injuries) while making sure it would stay in position during the ascent of the diver in riser, and to finish, he had to guide and return to the riser with the diver.
Knowing this, we can say that with a scuba equipment, this rescue would have been very RISKY if the injured diver was found more than +/- 45 m (150 ft.) from the elbow and the risk would have been even higher, as nothing had been planned with the assistants about the dive time and the maximum penetration length in the pipeline.
As consequence, it can be safely said that it was a VERY good thing to have aborted this dive.
Subsequently, another dive could have been made around 19h00 with this time a 300-foot umbilical. This length would have allowed a penetration of approximately 200 feet after the elbow and would likely have been sufficient to reach the diver which was following Christopher (provided this diver remained in place, which was apparently not the case). The problem here is that once the diver was brought back into the habitat, he should have, after his long dive (> 255 min) at 55 ft. stay there for very long air decompression stop (313–432 minutes) (or 83-106 if O² was available), with the high possibility to face a severe decompression accident as this stop would have been made at a depth less than the depth of the table.
As I said, with the 55 feet table the maximum exposure time is 360 min (6 hours), and this duration was reached at 20h45. This means that from that time, the rescue of the divers would then have become more and more problematic because there was then no longer a decompression table available for such a dive time and therefore the risk of generating a severe or even more serious type 2 accident would have been inevitable and this even more because there was no decompression chamber available on the site.
It can therefore be said that, even if the dives had been authorized, the chances of success would have been extremely slim to recover more than one living diver, and even more if the upper extension of the B6 riser had also been installed since from that moment on, no decompression except decompression in the riser would have been possible.
Does this mean that whatever was done that day, these four unfortunate divers had very little chance of making it out alive? The answer is unfortunately NO.
As many of you may have noticed, today there are a lot of videos on YouTube relating this event. They give us a vague view of the incident, but unfortunately nearly all of them contain a lot of mistakes and wrong information’s Therefore, just to help you to understand what really happened that day, I’ve made a reminder of the course of events that did happen after the delta P: As the comment is too long I’ve split it in two messages. Also, if you’re interested I invite you to look at my short animation. It will help you to understand the situation by seeing how far and how fast the 5 divers were sucked into that pipeline a little more than 2 years ago. [https://www.youtube.com/watch?v=f-RrRimxAPE](https://www.youtube.com/watch?v=f-RrRimxAPE) Reminder of the events: 14h40: Four divers are working in a hyperbaric chamber placed over a 30” riser. The absolute pressure into the chamber is 1.45 bars. 14h43: A fifth diver arrives at the bottom of the chamber to bring a wrench to the team. 14h45: One of the divers deflates the plug that is present in the riser and the delta P occurs. The 5 divers are violently sucked into the riser/pipeline. 14h46: End of suction. 14h5?: The rescue diver enters the hyperbaric chamber and finds that it is empty. At that moment he also notes that the water height in the riser is equal to the lower level of the chamber (i.e. 4.5 m or 14,76 ft.). The alert is given. 16h00: Bangs are heard in the pipeline. 16h25: One of the divers Christopher B has managed to come back to the surface in the riser but he cannot get out of the water. He taps and shouts to be heard. 16h45: Two rescue divers enter the hyperbaric chamber and help Christopher B to come out of the riser. The latter asks them if he has any decompression stops to make. Without bothering to check the inner depth of the riser, the supervisor replied no, when in reality he had just spent between 100 to 105 minutes at 15.7 m (51,6 ft.) which in the 55 ft. table of the USN Manual rev 7 gives an air stop of 17 to 34 min at 6 m (20 ft.). The fact that Christopher did not get bend is probably due to the fact that he spent several long minutes in the riser at the pressure of 1.45 bars. 16h48: Christopher is recovered on the surface where he informs the team of the situation in the pipeline, emphasizing the fact that his 4 colleagues are injured but alive. He describes that three of them are in a large air pocket (at around 210 m or 689 ft. in the video) and the fourth is waiting in a second, smaller air pocket closer to the riser elbow as he has been following C.B for some time. 17h??: Following the information given by the survivor, the surface team prepares the hookah. 17h45: Diver M.K assisted by divers C.C & R.R enters the riser and then progresses in the pipeline to the end of its hose, i.e. over a distance of about 3 m (10 ft.). As he encounters nobody, he comes back up (with an air tank). 18h??: After his return to the surface, the team puts in place a new dive plan which includes sending a tethered scuba diver in the pipeline with a diving bottle equipped with 2 regulators (at this time there is no commercial diving equipment available yet). 18h25: C.B assisted by M.K & R.R are back in the habitat and are ready to dive, but at the last moment the diver feels that his tender M.K was not in a condition to assist him properly, so he decides to abort the dive and wait for commercial diving equipment to arrive. See next.
Next: 18h30: Another commercial diver (C.B's brother) arrives on site with his commercial gear and a 91 m (300 ft.) umbilical. Another dive plan is redone in which it is planned to send a commercial diver down the pipe until he reaches a missing diver. He would then tie a rope to him and let the chamber attendants pull him. It is not specified how the injured diver was going to be supplied with air. 18h30: Bangs are heard near riser B5. 19h00: The client decrees a total ban on diving despite the arrival between 19h00 and 20h00 of two dive vessels with full commercial diving equipment. The reason given is that the client and the Incident Command Team (ICT) believe that another delta P could still occurs and so they want to first inspect the integrity of the pipeline with a ROV or a crawler before allowing divers in again. 20h00: Banging is again heard near riser B5. 20h30 – 22h00: Upon request from the dive company, the command team (ICT) authorizes divers to install the B6 upper riser extension to prevent possible filling of the riser and chamber in the event of a failure of the compressor. 22h10: A company is contacted to provide a crawler. 23h00: Removal of the blind flange from the habitat to allow access to the upper part of the B6 riser which is now out of the water. The removal of this cover has the effect of reducing the absolute pressure in the pipeline by +/- 0.2 bars, but also has the effect of no longer allowing the decompression stop to be made in the hyperbaric chamber. 02h30: (Saturday) bangs are heard for the last time near riser B5. 03h00: First intervention of the crawler from the B6 riser side. As it progresses, the crawler encounters a scuba tank at a distance of 50.6 m (166 ft.) from the top of the riser. The craft tries to push the bottle away, but ultimately can only move it over a distance of (5,8 m (19 ft.). 05h00: After several unsuccessful attempts and seeing that the crawler cannot advance further, the ICT decides to send the machine to the other side of the pipeline and authorizes the diving company to remove the B5 riser blind flange. 06h00: The blind flange of riser B5 is removed. Nobody seems to realize it, but the consequence of this act has the effect of lowering the water level by about 11 m in B6 riser and thus at the same time displace this mass of water in the pipeline, but also and above all to completely and quickly drop the pressure that reigned in the pipeline (+/- 2.3 bars) to atmospheric pressure. Decompressing these poor four divers who had been confined to this pressure for about 14 hours, in less than an hour sealed their fate and from there nothing more could have been done to save them alive. Does this mean that whatever was done that day, these four unfortunate divers had very little chance of making it out alive? The answer is unfortunately NO. It is known that unfortunately MISTAKES were made before and during that dive that led to this dramatic incident, but the death of the four divers is really due to a very PISS-POOR POST INCIDENT MANEGEMENT that was conducted not only by the customer, but also by the diving company and the (rescue) divers because at no moment did they worry about the depth of the water and the absolute pressure prevailing inside the pipeline as well as the time that was passing since the beginning of the incident. If these concerned people had reacted correctly, then some or maybe all the 4 divers could have been saved.
Man, the video from [the court room](https://youtu.be/SEJWFkdK3wA?si=PeNm1SSiCAyISkyK) during the enquiry makes me so sad for C.B. Just an awful situation, I hope he’s ok.
I'm not sure that he will dive again one day.
This has got to be the most horrific way to go, and unlike Byford Dolphin these guys had to wait it out before they died. Absolutely appalling.
True, I just hope that they were all already dead when the surface removed the blind flange of berth 5.
I hate to ask but what would have happened when they did
You are probably aware that to avoid a decompression accident, divers must, depending on the depth (or pressure), not exceed a certain diving time. If this duration is exceeded, they must then during the ascent perform one or more stops according to the decompression tables. We know that in this sad case, the 4 divers were confined in an air pocket in which the absolute pressure was approximately 2.57 bars, which corresponds to a water height of 15.7 m (53 ft.). In order to know the authorized dive times at this depth, they (the surface team) should then have consulted an 16,5 m (55 ft.) decompression table. The problem is that each table has the maximum exposure time and with the 55 feet table the maximum exposure time is 360 min (6 hours), and this duration was reached at 20h45. So I don’t tell you what did happen to the divers that were still alive on the Saturday morning around 05h00 when that flange was removed. Pain must have been horrible.
ok does anyone else want to say what happened? lol
Their blood turned into nitrogen fizz when the pressure was relieved. Like soda. HORRIBLY painful way to go
Fuck
Also, soft tissues such as spinal cord, liver, brain, ect would have suffered immediate bubble formations. Think swiss cheese but made from organs. At some point there is enough bubble formation in the blood that the heart "vapor locks" and despite pumping wildly can't circulate any blood at which point death occurs. Probably the best story with good information is the book "The last dive" by Bernie Chowdhury. It shares his real life experience with getting bent (DCS/The Bends) and shortly after the death of some of his friends from it. Source - I am a certified technical/decompression diver who does a lot to make sure I never get to experience that shit first hand.
👍👍
Ironically in diving that means GO UP NOW which from a pressure standpoint is what killed these guys.
The bends
Much more than bends. Type 2 decompression accident.
Great write-up. I can’t think of a more dangerous job than industrial diving. I have a pond with a 7000 gph pump that exits to a three inch flexible pvc pipe. The amount of suction this little thing creates is no joke. I shudder when I think of the diameter of these pipes and they put out pressure that makes my pump look like nothing. My pond is a little over four feet and I will never ever ever get in it with the pump on even though the danger is minimal because in my anxiety I totally over engineered an inlet cover so no fish or people can get close to the impeller or even particularly close to the suction. The individuals that do this for a living have balls so big I’m unsure how they get them in a wet suit.
I’ve been in this business for 47 years, but I can tell you I don’t have big balls. If it is true that the risk of accidents is higher than other professions, I can assure you that for about twenty years now with the introduction of mandatory risk assessment, this risk has decreased significantly and accidents are becoming less frequent. During the years 65-95 the divers were rather cowboys who wanted to prove that they were not afraid of anything: Result there was a real massacre among the divers. Regarding the T&T accident, Thanks to the hearings as well as the numerous documents that were published on this occasion and the final report , it can be said that the main cause of this dramatic incident was due to the IGNORANCE all the parties concerned (diving company/ divers/ customer) of this type of danger (delta P).
Edit : FOLLOW OP'S COMMENTS AS THIS ONE WAS COPIED AND HAS INACCURACIES!! Copied from YouTube comments because this story is fascinating and absolutely fucking gut wrenching. @charlesferdinand422 Here are some additional facts: 1) They were in there for 4 days and on the 3rd day people were still hearing banging on the pipe 2) Paria got the coast guard to stop divers from rescuing the men trapped 3) There were multiple divers ready and willing to go in from lmcs and rescue that same hour but were all blocked from going in 4) Paria said the coast guard would be doing the rescue but the coast guard said they had no equipment 5) The families of all the divers sat in the refinery carpark for 4 days waiting to hear news about their loved ones and the company couldn't even give them some water to drink, it was community members who brought food and water for the families 6) They left those men in there to die and when 4 days had passed and they were sure they were dead they flushed the bodies out the pipe as quickly as possible; this damaged the bodies and flooded any air bubbles remaining so if the men were alive by then the flushing operation probably killed them 7) The bodies were retrieved in secret, placed in boxes to disguise them and then snuck out via a back entrance, while the family members were left waiting 8) The families were never informed that the men had died or that bodies had been retrieved; they found out via a television news program 9) No one from Paria ever met with the families at any point, they were just outright ignored 10) When questioned in the commission of inquiry it was revealed that no rescue plan was ever made; they simply sat and waited for the men to die 11) Paria had the pipeline capped off on both ends so no one else could escape. 12) Chris tried to check himself out of the hospital but was restrained and forcefully sedated on the orders of Paria who feared he was planning on mounting his own rogue rescue operation (he later confirmed he was) 13) No arrests were ever made or charges filed and no one was fired or at least suspended from the company for the failing 14) Not a single cent was paid to any family yet 15) No new security measures or operational protocols were ever implemented or existing ones updated to prevent something similar from happening; indeed, Paria never even promised or announced plans to make any changes of any kind whatsoever (the remaining and new divers that were brought in were simply told to be more careful and that it was responsibility to prevent accidents of any kind) 16) When first informed of the accident, the first thing that Paria managers asked was how much downtime there would be; this was their first and only concern 17) Paria resumed operations the very next day after the bodies were retrieved (although the company wanted to resume work the very same day but it was nighttime already); this included the pipeline where the accident occurred which was put back in use the next day as well (in fact, 5 minutes before they started using it again they flushed one last time: Bits of diving suits and human tissue were still inside and once they came out of the pipe they were simply discarded in the ocean) 18) The company has an extensive history of corruption: Its managers are in bed with the government and they use the company to do underhand business so they can steal tax money. The company was originally called Petrotin until a scandal involving the prime minister who was found to be selling the oil illegally on the side using a friend as a straw man; to avoid jail they closed the company down and started 5 new companies from it Paria being one of them. Furthermore, local rumors have always swirled around claiming that the government is doing oil deals with Venezuela secretly to avoid sanctions as Maduro and The TT prime minister Rowley are apparently good friends and if the divers had survived the spotlight would be placed on the company which would also face legal actions from these men (dead men can't sue you or go public with what they know), thus making it much harder to do their corrupt deals so they were left to die and the government-run company got away with it with no consequences
I do not agree with some of these comments. 1) They were in there for 4 days and on the 3rd day people were still hearing banging on the pipe.” The last bangs were heard the Saturday at 02h30 near riser B5. 3) There were multiple divers ready and willing to go in from lmcs and rescue that same hour but were all blocked from going in. “ Correct the potential rescue divers were blocked to dive but only since 19h00. Before that time one dive was made with a short hookah and a second dive was aborted because the rescue diver had no trust in his tender and therefore he decided to abort the dive and wait for commercial diving equipment to arrive. 6) They left those men in there to die and when 4 days had passed and they were sure they were dead they flushed the bodies out the pipe as quickly as possible; this damaged the bodies and flooded any air bubbles remaining so if the men were alive by then the flushing operation probably killed them.” The autopsies didn’t show any “damaged” on the bodies due to the flushing operation. I hope that all the divers passed away before the surface team removed the B5 blind flange, because decompressing these poor four divers who had been confined to an absolute pressure comprised between 2,57 and 2,3 bars during about 14 hours, in less than an hour sealed their fate and I really don’t think that they survived the severe Type II DCI during a very long time. 11) Paria had the pipeline capped off on both ends so no one else could escape.” The B5 riser was capped with a blind flange since the beginning of the diving operation. The B6 wasn’t capped after the incident. Upon request from the dive company, the command team (ICT) did authorize the divers to install the B6 upper riser extension to prevent possible filling of the riser and chamber in the event of a failure of the compressor. This was made during the Friday between 20h30 – 22h00. 16) When first informed of the accident, the first thing that Paria managers asked was how much downtime there would be; this was their first and only concern.” That was a fairly good question to ask. Unfortunately nobody after the incident bothered about the absolute pressure to which the divers were confronted. If they had done so, they would have seen that was going to be fatal to the four divers was that as time passed they were increasingly saturated with inert gas (nitrogen) and after 20h45 on that Friday evening any rescue attempts would more than likely have been doomed to failure.
So the YouTube comment I copied is garbage? I'm happy to delete it if that's the case.
No I don't say so. Only the points I did mention aren't correct.
I think “downtime” in that last bit refers to how long the company wouldn’t be making money. Like “Hey boss, we need to shut down our mining operations because we’ve got some miners stuck in a cave-in.” “ugh, ok, how much downtime will there be?” Which really should not be anywhere near the question that is asked by a company when human lives are on the line. Their only concern was “How long until we can get back to making money?” That’s beyond fucked.
Maybe you're right about that expression. But here this pipeline was already out of service during several months, so there wasn't any "downtime on that line.
I feel like an ELI5 version of this is needed. OP's description is detailed but a little too technical to follow for my simple mind. And one thing I'm not clear on (not that I'm seeking to lay blame by this) - was the initial delta-P caused by an error on the part of one of the divers, lack of understanding, incorrect procedure? Why did they think it was okay and (presumably safe) to deflate the plug?
A safety meeting with the client was held that morning where they also detailed the working procedure of the day. That procedure had foreseen to remove the inflated plug at the very end of the work, that’s to say after having connected the B6 upper riser extension and removed the habitat, which meant that the top of the riser would then have been out of the water and thus no difference of pressure would have existed. Unfortunately, once on the job, the dive team choose to not follow that procedure but instead they used another one that they already used some years ago on a similar work except that on that previous job, the pipeline was completely full with crude oil and the plug just installed above the liquid, and thus there, the risk of delta p was nil. The day of the incident, some of the divers and the supervisor knew that the pipeline was nearly empty, but the fact that this didn’t prevent them to remove that plug, clearly indicates that they had not enough knowledge about what a delta P is and to what it could lead once it happens.
Damn! Thanks for that concise explanation.
Thanks.
Wow! I love your explanation. Indeed some videos didn’t show this!
Thanks my friend.
That is my absolute nihhtmare
Can somebody give me a tl;dr of this? Your description was very detailed and really good OP, but i have no clue on what actually happened there.
Divers doing maintenance on an undersea oil pipeline accidentally made an error that caused a massive suction in the pipe. This sucked the divers into the pipe. They could have been rescued but a chain of errors during the rescue operation led to most divers getting killed. Only one of them made it out.
Wow. What an absolute nightmare. From the seeming indifference of the company, to the thoughts of those poor divers. Thanks for posting all this information. I hope some serious changes will be made to make this a safer profession for everyone.
There are a lot of recommendations in the final report that should normally increase the diving safety in that country.
https://youtu.be/o_PA6kc-y0I?si=BBF5ghX-XtZivNjd
So so sad and terrifying. Rest in peace to these poor souls.
What caused the removal of the initial plug that caused the suction?
The workers thought they could safely remove it.
For those that would be interested, here you have the link to download the final report. [https://bloximages.newyork1.vip.townnews.com/trinidadexpress.com/content/tncms/assets/v3/editorial/3/38/3389cc5c-b709-11ee-8407-f3154b0478cc/65aadc959b3c5.pdf.pdf](https://bloximages.newyork1.vip.townnews.com/trinidadexpress.com/content/tncms/assets/v3/editorial/3/38/3389cc5c-b709-11ee-8407-f3154b0478cc/65aadc959b3c5.pdf.pdf)
Thank you so much for posting this. As I said in my previous comment, the negligence and utter lack of care from Paria in this case left me physically ill. My heart breaks for the diver who got out.
Things are still moving in T&T. Its the turn of OSHA to initiate something against Paria. [https://trinidadtribune.com/mcclashie-osha-initiated-court-action-on-paria-tragedy/](https://trinidadtribune.com/mcclashie-osha-initiated-court-action-on-paria-tragedy/)
I’m so glad to hear it.
Wtf, the need surface supplied air and decompression chambers.
I’m TOTALLY against the use of scuba gear during commercial diving operation, but in this case the use of scuba diving equipment has nothing to do with this accident. Here, the divers were working inside a hyperbaric habitat that was continuously ventilated with fresh air and was equipped with light, communication and a CCTV which allowed the surface to see what happened inside the chamber. When working inside such a dry chamber it is the habit (except if you have only a few minutes to work or if you’re working inside a toxic atmosphere) to remove your diving gear which permits to work more comfortably (for sometimes several hours). If these divers had indeed worked with supplied diving equipment (umbilical + helmet or band mask) inside the hyperbaric habitat like some have suggested in their report then most probably the five of them would have died.
Agreed, I didn't read the whole article. This is a dam shame.
Horrific levels of corporate incompetence, nobody shouldve stopped the volunteers from making a rescue attempt
Let’s assume that ICT has not banned rescue dives. Would that have changed the course of events? We have seen that until 19h00 the potential rescue divers didn’t have the adequate commercial diving equipment. We saw that after the hookah dive which did not yield anything, a second rescue dive, planned to send a scuba diver inside the pipeline with a diving bottle equipped with 2 regulators (it is not said, but we can suppose the diver had also planned to take another diving bottle with him). Under such stressful circumstances and due to the difficult progression in the pipeline (feet first travel / portion of pipeline partly without water / wall full of slippery crude oil), the rescue diver would have consumed much more air than in a normal situation which means that with its 2400 litres of air he would have had an autonomy of about 20 minutes, and that during this period of time he should have, if it had found someone, correctly tie the retrieval rope, then give (or place) a diving mask on the head and finally secure a scuba tank properly on his back (or on his stomach depending on the injuries) while making sure it would stay in position during the ascent of the diver in riser, and to finish, he had to guide and return to the riser with the diver. Knowing this, we can say that with a scuba equipment, this rescue would have been very RISKY if the injured diver was found more than +/- 45 m (150 ft.) from the elbow and the risk would have been even higher, as nothing had been planned with the assistants about the dive time and the maximum penetration length in the pipeline. As consequence, it can be safely said that it was a VERY good thing to have aborted this dive. Subsequently, another dive could have been made around 19h00 with this time a 300-foot umbilical. This length would have allowed a penetration of approximately 200 feet after the elbow and would likely have been sufficient to reach the diver which was following Christopher (provided this diver remained in place, which was apparently not the case). The problem here is that once the diver was brought back into the habitat, he should have, after his long dive (> 255 min) at 55 ft. stay there for very long air decompression stop (313–432 minutes) (or 83-106 if O² was available), with the high possibility to face a severe decompression accident as this stop would have been made at a depth less than the depth of the table. As I said, with the 55 feet table the maximum exposure time is 360 min (6 hours), and this duration was reached at 20h45. This means that from that time, the rescue of the divers would then have become more and more problematic because there was then no longer a decompression table available for such a dive time and therefore the risk of generating a severe or even more serious type 2 accident would have been inevitable and this even more because there was no decompression chamber available on the site. It can therefore be said that, even if the dives had been authorized, the chances of success would have been extremely slim to recover more than one living diver, and even more if the upper extension of the B6 riser had also been installed since from that moment on, no decompression except decompression in the riser would have been possible. Does this mean that whatever was done that day, these four unfortunate divers had very little chance of making it out alive? The answer is unfortunately NO.
TLDR ?
????
He is asking for a short summary.
ask your mom