A Brief History of: The Leningrad 1975 & Chernobyl 1982 Meltdowns (Short Documentary)

[@PlainlyDifficult]

If you're interested in Nordpass go to nordpass.com/plainlydifficult to try it out for free

[@AcornElectron]

I mean, I’m not, but I’m happy to click through if it helps the channel?

[@cobeer1768]

RBMK: Regularly Blow up/Melt down, Komrade.

[@bmstylee]

We need that reactor face on a sticker. And have you considered Times Beach for a disaster video? Absolute mess.

[@leftnoname]

According to some, Meltdown in Leningrad NPP could have ended in a similar disaster to Chernobyl, but the reactor fuel was much fresher (and more stable). That saved them that time. But one can go to the same well only so many times.

[@ribik64]

Can you please cover the 2001 Paks NPP incident?

[@rickgrendel1]

I like it that the RBMK reactor is now a character in the Plainly Difficult universe.

[@PlainlyDifficult]

Glowing head rbmk

[@rbmk__1000]

Thanks

[@gateauxq4604]

I feel so bad-he didn’t do anything wrong! He’s basically the USSR’s most abused child (children?)

[@rbmk__1000]

@@gateauxq4604 I just want to be loved, is it getting hot in here or is it me?

[@turtleguy123r3]

So true, I can't hear that name without thinking of this channel anymore!

[@JakusLarkus]

From someone who studies reactor design and operation for a living, I've gotta say your videos are spot on. All the details are correct and you've clearly done a loootttt of background research into the topic. Love the use of the word 'bugger' too... in the real world that word's usually followed by either a spicy blue flash or the complete destruction of some very expensive machinery.

[@PlainlyDifficult]

Thank you 😊

[@Durandal734]

Spicy blue is my least favorite spicy

[@sabrekai8706]

Actually I think that bliat (not sure of the russian spelling ) would be more appropriate. Usually the last word heard on a cockpit voice recorder if a plane crashes... Chit.

[@celeste1879]

“Spicy blue flash” the best thing I’ve read today

[@88manta88]

>reactor design and operation for a living What kind of job do you have?

[@NPrinceling]

"What's your disaster plan?" "Don't have a disaster." "Genius!"

[@Cybonator]

Could do a separate vid on the different types of radiation exposure? milliRem, Roetgens, etc Would be helpful to understand the severity of the accidents

[@anhedonianepiphany5588]

... _OR,_ you could spend a few minutes on Wikipedia learning about these units, and discover why radiological units, and attempting to compare or convert between them, isn't always a simple straightforward task.

[@RJStockton]

@@anhedonianepiphany5588 We can't all be Wikipedia scholars, professor.

[@quinnlevikinder-chase7631]

I would love this!

[@Terri_MacKay]

Great idea!!!

[@j.f.fisher5318]

@@anhedonianepiphany5588 seriously, I've done exactly this multiple times and the units still mean nothing to me.

[@cris_261]

"Easy to build," and "cheap." Two things you never want to hear when building a reactor.

[@neutronalchemist3241]

Fast, cheap and well done. You can have only two.

[@GhostOfDamned]

And that’s how fallout began

[@Draxindustries1]

Expensive, complicated and difficult to build can also equal big booma..

[@cytrynowy_melon6604]

The problem is that you don't want very expensive reactor, either. Modern nuclear reactors are very safe but very expensive, which makes nuclear loose against gas and wind/solar power. Nuclear power is either cheap and dangerous, or safe but too expensive, looking at the experience of last decades. Do research about how much it costs in total to create plans, build power plant, operate it, and fully decommission it after a few decades. Plus training staff and buying insurance for power plant. Crazy money

[@P7777-u7r]

@@neutronalchemist3241 Honestly you can only have one. Fast is never cheap and cheap is only well done if its the first of something

[@Lrr_Of_Omikron]

Disasters are always so inconvenient. Going off during shift change, how rude.

[@PlainlyDifficult]

They should follow the schedule better!

[@Lrr_Of_Omikron]

@@PlainlyDifficult exactly. See, someone els gets it. I say we come up with a committee that will put these free loading disasters in their place and teach them some civility. Or at the very least how to read the schedule.

[@mbryson2899]

When I worked as a Security & Safety officer at a large hospital our shifts overlapped to minimize the risk. Further, whenever we had ongoing emergencies or serious issues we were required to stay on until they were resolved or until the oncoming shift had the incident fully in hand. I earned a fair bit of overtime and we never had anything get out of hand.

[@sarahamira5732]

Ehhhh make it day shifts problem lol

[@lindada1111]

Just put a sign "no disasters allowed after 11pm to 8am on workdays and all day on weekends."

[@_KRose]

Smooth, black mineral - graphite. There's only one place in the entire facility you will find graphite: inside the core. If there's graphite on the ground outside, it means it wasn't a control tank that exploded, it was the reactor core. It's open!

[@TryksterJawbreaker]

Ok but maybe it was burned concrete 🤔

[@desertrose0027]

@@TryksterJawbreaker If there's one thing I know, it's concrete.

[@michaeljames4904]

All I hear is conjecture from someone I don’t know.

[@anhedonianepiphany5588]

HBO "Chernobyl" "jokes" weren't funny the first 412,388 times!

[@michaeljames4904]

Please escort @@anhedonianepiphany5588 to the nearest party headquarters... _(you’ve certainly earned your username’s meaning -the inability to find pleasure or joy in anything: Season’s Greetings! 😘)_

[@nameofthegame9664]

Imagine having procedures and parameters to work by but when the shit hits the fan you are forced to ignore that or you’ll have to go to the unemployment center the next day. The biggest problem wasn’t the RBMK, it was the work mentality of the USSR.

[@PlainlyDifficult]

Unfortunately true

[@nameofthegame9664]

@@PlainlyDifficult excellent video as always! Can’t wait for the next one!

[@sc1338]

They pretend to pay you, you pretend to work lol

[@DAndyLord]

@Richard Vaughn What? Where on earth do you live? I'm in Canada and that's utterly foreign to me.

[@smorris12]

He's probably a conspiracy nut. The Illuminati are taking over the West to inject everyone with microfishandchips yada yada yada

[@petergray2712]

Two precursor accidents involving the RBMK reactor. Soviet technocrats: Two accidents, not great, not terrible.

[@Skullair313]

Comrade, those accidents never happened and any claim stating otherwise is a capitalist plot and therefore high treason. Glory to the Union -Soviet minestery of energy

[@johnathanblackwell9960]

Of their K series Subs the one they kept in service the longest is the one that killed the most people and suffered the most nuclear accidents. I seriously question question the Sanity of both the USSR and the Russian Federation.

[@vonfaustien3957]

@@johnathanblackwell9960 I mean there first military reactor that they used to make weapons material had an open loop feedwater system and just pulled in water from a nearby lake shoved it into the core and dumped it back out. Most cores had a closed loop so contaminated feedwater stayed in the system. They did retrofit it to use tanks but they skimped on cooling and they blew up. Its arguable the area around lake mayak is more contaminated after decades of that shit than the Chynoble exclusion zone

[@thygrrr]

That's not a lot of accidents per fuel channel. Come on. :)

[@pokergroupdigital5290]

Two accidents? Well thats not great, but it's not horrifying.

[@thegoods1r694]

and that is how an rbmk reactor explodes

[@PlainlyDifficult]

Dangerous design for sure

[@michaeljames4904]

_”the same reason we’re the only country to use graphite moderated reactors [using under-enriched fuel] with a Positive Void Coefficient ... it’s cheaper”_

[@Wafflepudding]

lies!

[@EvilTurkeySlices]

@@PlainlyDifficult I think a few are still in use(could be wrong though)

[@leonthepromoreno]

Take him to the infirmary, He's delusional.

[@HyperionGamingTOPKEK]

Last time I clicked this fast the xenon was still iodine

[@PlainlyDifficult]

😂😂

[@waynetemplar2183]

👍

[@TrianglePants]

creative format gettin old though

[@trumpet12345]

Behaving like iodine and BEING iodine are different. I didn't check the radiologic (so to speak) table, and I love the joke - but, you always have to * or something with ongoing elements of shift. There just likely is no common name for the difference, but I would hope my limited chemistry would dictate that anything of shift isn't possible to label correctly based on periodic table. Also before anyone tsk tsks me. Go tell the USDA to retest everything as real science disagrees with the original test vs now. I doubt anyone wants to be the person that signed off on 4 extra calories though.

[@Bagheera2]

I feel like this is a decay joke...

[@agenericaccount3935]

Trainee who later worked at Chernobyl: OH NO NOT AGAIN

[@Iffy350]

Chernobyl veterans! Join Duty! Help us protect the world from the Zone!

[@thatsnodildo1974]

I was gonna make a Joke about how Soviets who worked on nuclear subs would say the same thing but half of them are 6 feet underground and the other half are 600 feet under water

[@timurtheterrible4062]

@@Iffy350 Duty? More like Doody. Join Freedom today!

[@bmstylee]

Later worked at Chernobyl? Anatoly? Is that you?

[@faithjacksondocherty8970]

I hate that I laughed at this

[@johnladuke6475]

I love the way that they FINALLY pressed the SCRAM button in the first incident. Because all those times the reactor tried to SCRAM on its own all night long, that was clearly just a series of annoying false alarms. Great job, Soviet reactor operators.

[@lostmymarbles9151]

I can literally count on my hands how many times I've been to Chernobyl.. 13 times.

[@c0mbo]

Your hands have 13 digits?

[@c0mbo]

@@jazzcat5950 yeah, I understand))

[@raphaeldexel4356]

@@c0mbo this exists...it is called Polydactyly....

[@clarky4213]

@@c0mbo you mean your hands dont? Shame on you for being different 🤣🤣

[@NoahSpurrier]

Two hands with extra fingers or extra hands with five fingers? What kind of mutant are you?

[@drboze6781]

I remember reading about the startup of the B reactor at Hanford. After it successfully went critical, all the big-wigs went home to dinner. Shortly thereafter, it shut down by itself. They later realized it was the xenon poisoning. Fortunately, DuPont had ignored the engineers ideas on the number of fuel rod cavities and had extra ones available to rid the reactor of the poison. Imagine running a machine based on a theory and having to write the operating manual as you go. Fun fact: There was a sign on the main control saying, "Don't bump the control panel!"

[@Falchieyan]

~9:35 mentioning that the only disaster account is from a tech that went on to work at Chernobyl. THAT GUY. I feel like he would end up with a personal vendetta against RBMK reactors. The Batman of RBMK reactors.

[@Stoney3K]

He was probably the guy in the control room that was immediately kicked out when saying "Maybe you shouldn't do that" as the plant manager ordered the fateful AZ-5.

[@savagedk]

In 1983 Ignalina NPP in Lithuania demonstrated the same design flaw. Thankfully the rods did not get stuck this time or disaster could have occoured.

[@anhedonianepiphany5588]

These were 2 x RBMK-1500 reactors that had the same inherent flaws as Chernobyl's RBMK-1000 units, though both have now been decommissioned. By the way, the Chernobyl disaster wasn't _caused_ by stuck control rods, as it was the damaged core - exacerbated by the _entry_ of the rods' graphite extensions - which made further insertion impossible.

[@michaeljames4904]

@@anhedonianepiphany5588 Okay, but that word “caused” is surely doing a lot of heavy lifting: such disasters invariably happen, as PD often recounts, because a litany of disparate causes each end up piled on the previous ones; including deliberately ignoring safety protocols put in place to curtail exactly the sort of disasters that are precipitated. The later Control Room of Chernobyl’s Reactor 4, likewise _knew_ they were similarly in a Xenon pit and that the *prescribed procedure* was therefore a gradual restart over 24hrs. NOT yanking all the control rods out fully, even overriding the automatic safety rods too, leading to graver issues still on subsequent SCRAM reinsertion - _they shouldn’t have all been out in the first place!_

[@johansoderberg9579]

Xenon poisoning was a major contributor to the accident in Chernobyl. Xenon is an effective but hence also burnable poison. Wherever in the large reactor, a local increase in power occured, xenon was burnt and the local k further increased and so on... :-(

[@jefftaylor1186]

The more and more I study this it seems like the whole thing would’ve been avoided if they just told operators about the graphite displaces on the ends of the control rods. That way they would never pull them all the way out. They would pull them all the way until the graphite was still in if they needed to accelerate a reaction instead of pulling it all the way out. That way if they need to scram the reactor, reactivity wouldn’t surge because the graphite was already there.

[@johansoderberg9579]

The graphite displaysers may have contributed but the main cause was the low steam quality / high coolant flow forced them to withdraw rods to an extent far more than enough to run the reactor att 100% with normal steam quality. In addition to that xenon acts as a burnable poison resulting in instable power distribution, especially in a reactor of this type with huge physical dimensions. - The graphite tips is a typical russian way to defend a serious mistake!

[@nicholas_scott]

It is amazing that the flaw that led to the Chernobyl disaster had nearly led to disaster in 82 and 75.

[@xponen]

the deity wasn't cruel, they have been warned, twice.

[@KingOhmni]

Last time I clicked this fast there was twice as much U236 in existence...

[@CraftyF0X]

Presumably about 23480000 years ago ?

[@KingOhmni]

@@CraftyF0X I'll assume the maths is sound but...er... it was a joke, I trust the half life of comedic value exceedes 2.3 x 10 to the power of 7 :P

[@lofthouse23]

I'm glad the problems were sorted out after the incident in the 70s, thus solving the issue once and for all.

[@Killerean]

The graphite "tips" were actually rods of almost equal length to the boron control rods. The idea being that this reactor should run very low enriched fuel, thus needing all the acceleration it could get. However, this design have also proven lethal in 1986, as the scram procedure causes the reactor to briefly accelerate. That occurs due to a design quirk where the graphite moderator rod is purposely slightly shorter than the core itself to maintain equal reaction, using light water as an inhibitor. Unfortunately, as control rods are a two-part rods, the boron inhibitor rods cannot be inserted in to the core unless the graphite moderator rods are pushed out of the reactor. When this happens, water is pushed out of the channel, leaving the bottom of the channel to be accelerated to more than 100%. In 1986 Chernobyl, scram procedure was initiated too late, and the graphite rods jammed themselves in to the bottom of the core, leaving the reactor in full throttle. Hypothetically, identical incident could have happened in 1975 and 1982, however, the operators were, it appears, in "luck" as the insides of the reactor gave up first, triggering the alarm.

[@AthosRac]

The UN report made by physicist of all countries did not mention Scram procedure as the cause of the meltdown. This was speculated by USA side to highlight a POSSIBLE weakness in the soviet designe. Despite being a weakness, there is no proof or the button was pressed and no one in the control room claimed to have pressed it. So the contribution of the tip of the rods is pure speculation. The report is available in the internet and you can READ it by yourself.

[@frozendude707]

The thing I remember the most about Chernobyl is that the meltdown leaked enough radiation to trigger the radiation alarm and subsequent evacuation of a nuclear power plant in Sweden, some time after the winds had taken it over land and sea.

[@MrJokkoma]

What makes the Rbmk reaktors so interesting is how they can act like they have their own life. Notoriously unstable at low power, xenon poison, hot spots, and not to forget that positive void coefficient, all these words we never had heard before, and how that design whit the grafite tiped boron rods made the whole event a complete runaway, so dangerous that no man can control it. It's fascinating in a scary way.

[@88manta88]

If people had been properly trained, it wouldn't have been a problem. Xenon poisoning is a problem in EVERY reactor. Reactivity is usually handled via Boric acid in the primary coolant and thus equalizing automatically any hot spots. If you use only rods (way cheaper), every reactor will develop hot spots. Positive void is present in all the Canadian CANDU reactors and easy to handle with large bandwidth control loops. Light water gives negative void, but makes the reactor "inefficient". A reactor with a high conversion ratio needs a large Core, no light water and a good reflector. Then you get a "nearly breeder". The best right now is the EPR with 0.7 - meaning for every amount of fissile material it "burns", it breeds 70%.

[@SimonBauer7]

the rbmk is like a highly tuned 2 stroke engine with huge resonance exhaust, mixed with a diesel engine that is about to runaway meaning if you go full throttle at low rpm (in this case power) you get no reaction, but once it reaches resonance it goes wild making it shit to control.

[@adrianprince9617]

The thought of having many videos about this topic specifically gives me 3628473928373 years of peak serotonin output. Everything is so well researched, accessable in it's explainations, and absolutely hilarious. Thank you so much for all your hard work!!!

[@PlainlyDifficult]

Thank you!

[@MazeFrame]

Compared to other reactor designs, this one is quite brilliant when you think about it. It runs on whatever you dig up, can be built by normal industrial workshops, makes plutonium (at the time, quite usefull to keep the US of A from getting overconfident) and can be refuled without fully shutting down. Shame there were a hand full of fatal design flaws left in.

[@TheNavalAviator]

True, it wouldn't have had to be dangerous if they hadn't decided to push the boundaries of economic performance that hard and had higher overall safety standards. ½ the cost of a heavy water reactor would have been enough.

[@88manta88]

I want to emphasize the channel design. Forging and welding a pressure vessel is an insane job. Using a multi channel reactor and having the fuel "outside" is actually really smart. An RBMK is actually quite close to the advanced CANDU

[@laddb5148]

"Think of this as how Hobbit is to Lord Of The Rings... which will be the Chernobyl disaster of 1986" That cracked me up

[@bificommander7472]

"The fellowship of the rods" "The two fuel channels" and "The return of the graphite tips."

[@grmpEqweer]

@@bificommander7472 🤣

[@briancox2721]

I would have been here earlier, but someone was stepping on my foot.

[@YorkshirePirate]

I was in the toilet.

[@Doping1234]

When it comes to the reactor accident in Chernobyl I can recommend 'midnight in Chernobyl' by Adam Higginbotham. Absolutely amazing book going into detail of the history of the plant, the accident, the cleanup, and the soviet beaurocracy.

[@rbmk__1000]

Is no accident, is a okay

[@jackycook64]

Another good one is Chernobyl Notebook by Grigoriy Medvedev.

[@neuralmute]

Both are excellent books! Of course, the trifecta wouldn't be complete without recommending "Voices From Chernobyl" by Svetlana Alexievich. It's not at all technical like the other two, being an investigative journalist's collection of accounts from those affected by the accident; everyone from plant workers, surviving first responders, people who lost their homes to the fallout, children, historians, farmers, poets, soldiers, and the Liquidators who cleaned up the mess. It's a pretty chilling read, but with grim poetry, too. Alexievich won a Nobel Prize with this book, and I think it's well deserved.

[@stajger832]

I prefer prof. Serhii Plokhy Chernobyl book.

[@jackycook64]

@@neuralmute It is difficult to articulate just how much Voices of Chernobyl did for those impacted by the disaster. I hope no one takes my following comment wrong because I have nothing but respect for everyone impacted. For lack of better wording Voices of Chernobyl "humanized" it. It is easy to feel detached when we hear about a disaster as we do not see or hear the scope of the damage and the trauma of those involved and close by. When a picture or voice is given, it decreases the detached feeling and replaces that with empathy. We may have always had empathy but I believe it becomes much more personal when we see and or hear from those involved and not just the "spokesmen. I hope people understand what I am trying to say.

[@catskillwoodgas]

No Saturday is complete without a Plainly Difficult video.

[@PlainlyDifficult]

Thank you!

[@napoleonibonaparte7198]

“...who later worked at Chernobyl.” I pity the man.

[@kinetkraygunn9432]

Last time I clicked this fast I was doing an impression of the Geiger counter they mounted on the truck to measure the open core

[@PlainlyDifficult]

😂😂

[@Tindometari]

😄 When your Geiger counter makes a sound like you just stirred up a nest of rattlers ... it's just possible that you have what is commonly called 'a situation'.

[@AcornElectron]

11:47 immediately reverts to English for ‘bugger’ 😂😂

[@rbmk-1000-g8g]

I'm not bugger! I'm not monster!

[@chief5861]

So glad you decided to cover this series of events. There's a large coverage of Chernobyl but a large majority of it is limited to talk about whether it was steam or a nuclear detonation.

[@pokergroupdigital5290]

Reactor: "my graphite broke" Dyatlov: "you didn't have broken graphite!"

[@amyshaw893]

2 different RBMK meltdowns? But that's imopssible, the RBMK cant fail...

[@EduardoEscarez]

2 meltdowns and almost one big accident on Ignalina Power Plant before Chernobyl.

[@TerryClarkAccordioncrazy]

Actually they were kind of right, if operated within its design parameters it wouldn't fail. But that would have meant a long wait after shutdown before attempting a restart

[@Stoney3K]

Let's just say, the RBMK was a titanic beast of a unit.

[@Aatell764]

@@Stoney3K yes it was

[@tommysdreamhamilton3216]

"It didn't take into account the factor of the human way of Buggering things up ". Lol love it n yr videos tyvm

[@kieranh2005]

Every time that the genius engineers design something that is completely idiotproof, they underestimate the genius of complete idiots.

[@rogercroft3218]

@@kieranh2005 People forget that new, improved idiots are always in development.

[@lewisdoherty7621]

I wonder how many times the reactors may have developed Xenon poisioning and the management decided not to wait for it to clear, decided to try to try to overwhelm it and got away with it? It's OK, we have done this before and nothing really bad happened. The physicists who write these manuals are always worried about theoretical worst case scenarios which never happen. If we don't get this thing back on line, we know what is going to happen.

[@hooviedoovie5220]

One of the biggest misconceptions about RBMK reactors is the positive void coefficient. The issue is not the use of graphite as the moderator, it is the amount of graphite used in relation to the amount of fuel. The RBMK reactors are overmoderated, which means that if moderator is removed(voids in cooling water), reactivity goes up. (i.e. positive void coefficient) The same thing would happen in an overmoderated reactor with the use of any other moderator and using water as coolant Western reactors have a negative void coefficient because they are undermoderated. This means that as moderator is removed, reactivity goes down. Graphite is not necessarily the problem, although when using graphite as a moderator, it is hard to create an undermoderated design.

[@derekp2674]

British CO2 cooled graphite moderated reactors are over-moderated by design. This ensures safety in the event of steam ingress, if water leaks in from boilers tubes. An under-moderated design would be undesirable. But, in theory, wouldn't it be easy to build an under-moderated core, by using less graphite?

[@michaeljames4904]

But, surely, this is all interconnected? There is the excessive graphite, as you say, and the (imho inherently dangerous) PVC... the element you’ve left out, however, quite literally, is the under-enriched fuel -from which it is infinitely cheaper to fabricate fuel rods. It is precisely because RBMKs utilised such inferior fuel _that they were over (graphite) moderated, no?_ Lower Enrichment = fewer fission events = more need to slow down neutrons to enable collision = more (excess) moderation. With such poor fuel had they used less graphite reactor efficiency would likewise have sunk, hence why they used more.

[@derekp2674]

@@michaeljames4904 I don't think the fact that RBMK designs use lower fuel enrichments than PWR's means they had to be over-moderated. As Hoovie Doovie said, it is necessary for PWR's to be under-moderated by design. This is needed to ensure passive safety by means of negative void coefficients and negative temperature coefficients of reactivity. As I mentioned above, AGR's are designed to be over-moderated because that ensures negative reactivity feedback in the event of steam ingress. In theory, it would have been possible to design RBMK type reactors with under-moderated cores. That would have given a negative void coefficient but would have given positive reactivity coefficients for faults like water or steam ingress (as might be caused by coolant leaks). So I guess that one design flaw in RBMK type reactors is that designing in fault tolerance to water ingress inevitably gives the penalty of a PVC under low power operation.

[@drewgehringer7813]

Yeah, CANDU heavy water reactor design has a pretty good safety record even though its slightly overmoderated, the positive void coefficient is slight enough operators or automated systems have time to notice and respond

[@MissMyMusicAddiction]

@@drewgehringer7813as we have seen from these two events, reliance on the operators to do the right thing is a design flaw, apparently. it's so annoying, to me, every time that we talk about these two events (and many others), we say "design flaw". Really? If a human had followed the manual, would the event have happened?

[@matteckert7541]

Probably my favorite KZbinr, I don't know much on these subjects but they've always fascinated me. Thank you sir.

[@off_mah_lawn2074]

This is what happens when managers are given power not from their education or experience in the field, but on political connections.

[@jennteal5265]

And humanity never learns. Case in point: Venezuela's oil industry

[@off_mah_lawn2074]

@@jennteal5265 true story

[@nicostenfors5690]

I live in Finland across the water from Sosnovyj Bor. Im quite glad they shut down the RBMK a few years ago. Rumours say when it was still in use they just put a note over AZ-5 which said "Do not use"

[@Phredreeke]

Nico Stenfors two of the RBMKs there are still running, they only shut down the first two.

[@Stoney3K]

Imagine having a very big red emergency stop button in you control room, and then having a locked box with "DO NOT PRESS UNDER ANY CIRCUMSTANCES" put over it.

[@nicostenfors5690]

@@Phredreeke Oh crap, i tought all of the RBMK's were shut down but apoarently not.

[@RobBoss757]

"Sir the reactor is showing faults!" Sir "Eh accelerate to 1000mw output. What can go wrong?"

[@djohn4904]

mccfly?

[@mojoblues66]

The reactor is more stable at higher output. That's inherent to it"s design and would play a major role in the Chernobyl desaster later, where the accident started when they tried to operate the reactor at lower output.

[@CesarinPillinGaming]

@@mojoblues66 I think he means that the culture of the time was remove all rods to try to boost the power as fast they could while the reactor was heavily poisoned.

[@daszieher]

@@CesarinPillinGaming as if an engine clogged up when running below a certain load/rpm and declogged itself when under load. So when below minimum rpm with the engine coughing, of course you let'er rip! That'll free 'er up.

[@amberblyledge7859]

@@daszieher I did that to a car once. It didn’t like it. Turned out to be a sparkplug dying.

[@TheNuckinFoob]

You should do the Texas City Refinery Explosion of 2005. It was a case of runaway diesel which is insane to think about.

[@TerryClarkAccordioncrazy]

This pre-Chernobyl is a fascinating story that is little known. Thank you for informing us. It's exactly like the 737 max where all the signs were there in the first accident that could have prevented the second, but were covered up.

[@NexVoidGaming]

Alright. Saturday's over. Time to go back to bed and wait for next Saturday.

[@PlainlyDifficult]

😂😂

[@onlyonewhyphy]

I only found your channel a few months back and I'm confused by my desire to learn about these awful fuster clucks! I watch everything you upload 😣

[@PlainlyDifficult]

Welcome aboard!

[@EduardoEscarez]

It's a good channel. If you want more industrial fuster clucks, you can check the channel of the US Chemical Safety Board, or USCSB.

[@acemobile9806]

@@EduardoEscarez that USCSB is a real eye-opener. Brings into perspective the hidden fury that lurks around many industrial settings just waiting to be unleashed

[@thatsnodildo1974]

When people point to Chernobyl as a example to be anti Nuclear but its actually a prime example of how a toxic work mentality and inferior parts can lead to disaster

[@Skullair313]

Yes, but even western plants are not immune to this kind of fault. However, the main problem with noclear power these days is the aquisition of uranium and safe and permanent disposial of the waste.

[@moabitrockt]

It's unbelievably expensive once u calculate all the cost. Stupidity or ignorance are well displayed in every culture.

[@gothempress]

I have OCD and I really appreciate you doing a fundraiser to help people like me. It's a really tough mental condition to fight through on a day to day basis. Healing is possible, and the better quality treatment and care people like me can get, the better chances at regaining agency over our lives are.

[@jefftaylor1186]

The biggest flaw in the RBMK was the inability to measure the thermal rating at the bottom of the reactor.

[@LEVI040910]

That illustration at 10:10 has me dying 😂😂😂😂

[@Ferretsnarf]

The worst design feature of the RBMK reactors wasn't necessarily the corners cut, but a refusal by the ministry in charge to allow operators and engineers in charge of the facilities to truly understand *why* the regulations were the way they were. Rather than cut the corners and acknowledge the issues the cut corners raise to at least mitigate the risk and effects, the choice was made to cut the corners and make the procedures contradict the management initiatives and culture without a clear explanation to why the procedures were created. It was this choice that maximized the risk that these reactors posed.

[@MinSredMash]

Agree. Even with the appalling risks inherent in the RBMK's design, two short sentences added to the regulations would have sufficed to avoid the disaster.

[@derekp2674]

That said, any high hazard plant that depends on operator controls for its safety is a poor design. In the UK we recognise a design hierarchy, with inherently safe plant at the top, then passively safe plant, then automatically safe plant and finally administratively safe plant at the bottom. Here: Inherently safe - won't ever develop faults. Passively safe - become safer if faults develop. Automatically safe - are made safe by automatic system if faults develop. Administratively safe - require operator actions to keep them safe if faults develop.

[@93ophr3ak]

I swear I have "watched" this entire series ten plus times but I have seen it in its entirety. 😂 I love watching most everything you put out but I always fall asleep watching the episodes that peak my interest. I don't mean to say it puts me to sleep, but I enjoy falling to sleep listening to intriguing and educational videos

[@dfresh93086]

It’s so frustrating knowing that the writing was plainly (no pun intended) written on the wall about RBMK reactors, yet nothing was done to keep something like Chernobyl from happening. It all became a sick inevitability on April 26, 1986. Damn the USSR for allowing this to happen, especially with all the warning signs. They will always have blood on their hands for this.

[@meghanhause9435]

This was the point that the Chernobyl mini series was all about, the lying and covering up stuff, that in the end will come out and bite you in the butt. One of my favorite quotes from the mini series pretty much sums up the USSR's mentality at that time. "When the truth offends, we lie and lie, until we can longer recognize the truth, but it still there. Every lie we tell, owes a debt the truth, and sooner or later that debt must be paid."

[@michaeljames4904]

It was inevitable the moment they constructed finely balanced reactors *without containment vessels* for the convenience of refuelling while operational! (it was _disbelief_ that an RBMK might ever explode that I found the most far-fetched part of the otherwise superlative HBO miniseries)

[@misham6547]

​@@michaeljames4904to be fair the RBMK was far from the only reactor to be without a containment

[@maddoxXL101]

Finally a video on Chernobyl!!!!! is this first time you've uploaded a video on this subject cause i thought i had seen a video by you on the subject before but i could never go back and find it lol

[@n4sc3ntbrother]

Really appreciate what you do

[@PlainlyDifficult]

Thank you

[@sabrekai8706]

The problems caused by the secrecy were shown at some length in the Chernobyl TV series. Left hand had no clue about the right hand's screw ups.

[@jenniferbaldini3527]

Loved your reactor face!

[@hypercomms2001]

This scenario at Leningrad, sounds you eerily like what occurred at Chernobyl.....

[@mkbarber65]

John you have an awesome channel. Your research is very interesting and it’s surprising how much detail you are able to obtain. Thank you for some great information, I’ll be watching for a long time! Take care of yourself and stay safe. Merry Christmas and a very happy New Year.

[@PlainlyDifficult]

Thank you! Happy holidays to you too!

[@PapaThiccc]

You're one of the few channels that I've got notifications on for. I love the videos and I always watch them with my mom. I'm up in Alaska and we're both blue collar workers. So this is the stuff that we love.

[@PlainlyDifficult]

Thank you I really appreciate it!

[@freontec]

A shirt with your two dudes in chem suits and a speak bubble with "bugger" would be amazing

[@Raymonkey77]

Thanks for this video. I've always been curious about this since it has been referenced in many chernobyl documentaries I've seen. It would be cool to see a full length video documentary about this one, I've seen references that suggested more than a few accidents happened here

[@uzaiyaro]

Its kind of sad that the RBMK was such an unstable beast, because it was kind of genius in its design. Although I guess the closest Western analogue is the CANDU, which if I'm not mistaken, has a perfect safety record, and can be refuelled without shutting down.

[@swokatsamsiyu3590]

A CANDU is one of the safest, most robust reactors out there with an impeccable safety/ service record. And yes, a CANDU really does look like an RBMK, but then put on its side. For all intends and purposes it is what an RBMK could have been if they had sat on the design a bit more and give the RBMK the things it should have had from the start. The two reactors share the same pressure tube design and on-power refuelling capability. The CANDU even shares the same, albeit way smaller, positive void coefficient. However, the CANDU has two fast-acting separate shutdown systems which can shut the reactor down within 2 seconds without operator intervention where before the accident it took the poor RBMK between 18 and 21 seconds(!) to accomplish that feat. That might as well be 18 days in nuclear physics time when the chips are down. The CANDU also doesn't have the graphite moderator which only exacerbates the positive void problem. So yes, you are quite correct that one can see the CANDU as a Western analogue to the RBMK, but done extremely well.

[@mml100pink]

The closest Western analog is actually the (now defunct) B Reactor at Hanford in Washington State. It's literally a water-cooled, graphite-moderated reactor.

[@rbmk-1000-g8g]

​@@swokatsamsiyu3590hello, swoka! Are you ok?🥺

[@swokatsamsiyu3590]

@@rbmk-1000-g8g Yes, I'm fine, thank you😄

[@rbmk-1000-g8g]

@@swokatsamsiyu3590 пожалуйста, ответьте мне на последний комментарий к видео, где останавливали реактор, я за вас переживаю, вы такой добрый человек(((🥹🥹🥹😭😭

[@nicholasmarch3519]

Water does not boil into steam in a PWR as is incorrectly stated around 3 minutes, it's kept at pressure specifically to avoid that. The boiling occurs in the steam generators, so the only voids in a PWR are from nucleate boiling on cladding/surfaces at saturation temperature which has a negligible influence on reactivity for normal operating conditions. During accidents is when voids and boiling of coolant in the core is important/possible for a PWR

[@SicklyWindows]

thank you

[@Phil-D83]

These reactors were big, powerful, cheap to make, and created a lot of weapons grade material. Amazing how badly it was managed.

[@a_man_from_nn]

"and created a lot of weapons grade material" These reactors were not used for the production of plutonium, and were not even designed for this. It's just that their design was _partially_ copied from military industrial reactors. For example, the mechanism for loading and unloading fuel during operation.

[@korealaaya1826]

The amb reactor was Made for making, weapons grade plutonioum.. the rbmk where Made to make tons and i mean A FUCK ton of steam, they Even used to heat cities, power a bio gas plant, and heat a farm to grow crops in winter

[@veroxid]

Just remember: their computers tried to yell at them to stop multiple times. *_MULTIPLE_* times. This was 100% human error.

[@DefconMaster]

Hmm, a mistake by operators leads an RBMK to fall to low power levels and succumb to Xenon poisoning and pressure from management to get it back online leads to most of the control rods being pulled out which results in a power surge and core damage? Where have I heard this before?

[@TheIcyWizard705]

I've got to say having seen your videos over time you're always getting better at your presentations, especially with the illustrations and how they seem to gain details with every video

[@SasquatchTrevor]

"Think of this as the Hobbit is to The Lord of the Rings." You can title this as, "The RBMK: an Unexpected Meltdown."

[@TheNasaDude]

The Comrades of the RMBK The two cooling stacks The return of the Röntgen

[@Aaron-zu3xn]

still my go to video to cure insomnia i've got a playlist of your videos i put on loop and lay down to listen

[@soundspire360]

“Warning: there has been a balls up” is an alert I think all nuclear reactors should have

[@Tek_777]

Got me with the title! I thought we were finally about to get the full PD breakdown of the infamous 1986 disaster. Well done anyway, love the videos

[@thejudgmentalcat]

Mrs. PD deserves some love from the PD fanbase. She obviously keeps the subcritical mass of the family demon core from going critical, thereby ensuring PD will be able to make new videos and rate them with fridge magnets 😁 Btw I'm so scientifically ignorant I had to Google the terms used above 🤯 Love your stuff PD, hope I made someone smile 😆

[@PlainlyDifficult]

Thank you! She definitely needs more love!!

[@roderickwilliams67]

Finally I've been waiting for you to cover this topic

[@Syclone0044]

6:50 Sorry it was our fault

[@bellatrixoficialaverdadedo1031]

How.

[@Syclone0044]

@@bellatrixoficialaverdadedo1031 I’m a Plainly Difficult KZbin member, just tap the Join button next to Subscribe. I pay $1 a month to support this channel and I get these special nuclear ☢️ emojis lol!

[@fiatpandaman999]

Wanted to take a moment just to say how much I enjoy your content. It's so refreshing to not get clickbate content that's well researched, weel presented and enjoyable. You do an awesome job.

[@LongPeter]

3:42 My new favourite Plainly Difficult face.

[@rbmk-1000-g8g]

Cute

[@ralphhyre4973]

There was a St. Petersburg nuclear incident in the 1991 which is hard to find documentation on, but also involve the release of radiation to the public.

[@justjohn1461]

FINALLY, the video EVERYONE has been waiting for lol. ("Love the content btw")

[@PlainlyDifficult]

Thank you!

[@CTXSLPR]

The Graphite Moderated, Light Water Cooled reactor is not a design seen solely in the RBMK. The US Hanford Pu production reactors, including N reactor which was connected to the power grid, were all of this design as well. N reactor did have a vastly different design which did have a negative feedback loop for the coolant boiling (void coefficient).

[@mml100pink]

Thank you! Came here to comment this! I live here in Washington State and had the honor of visiting B Reactor in October 2019. It was water cooled, graphite moderated, and when Chernobyl happened, US officials said we'd never had a reactor with that danger in the US. It also had the dubious honor of producing the plutonium for the Fat Man bomb dropped on Nagasaki.

[@bryonjackson3209]

Hey have you ever thought about having a short video about the difference between all the measures of radiation? You know, nothing too involved but perhaps a brief discussion for us boneheads who appreciate your work but don't know enough about radiation?

[@FinalManaTrigger]

www.nrc.gov/about-nrc/radiation/health-effects/measuring-radiation.html Bequerels and Curies deal with the radioactivity of a substance, while Roentgen is dealing specifically with the amount of ionizing radiation in the air. 1 Bq = 1 decay/sec 1 Ci = 37,000,000,000 Bq rads/Greys, and rem/Sieverts are about radiation absorption. Grays and Sieverts are equivalent when dealing with Beta and Gamma radiation, however Alpha and Neutron radiation absorption is much more dangerous, so the Sv count will be higher than the Gy. For practical purposes, 1 R (Roentgen) = 1 rad (absorbed dose) = 1 rem or 1000 mrem (dose equivalent). 1 Gy = 100 rad 1 Sv = 100 rem Absorbing ~5 Gy or Sv is almost certainly fatal. Just to show how bad the Chernobyl disaster was, they were measuring 15,000 Roentgen on the roof, which is certain death 30x over with just an hour's exposure.

[@anhedonianepiphany5588]

@@FinalManaTrigger I believe what much of the audience is _truly_ seeking is an _oversimplification._ They require a simple scale, so we should just reduce all radiological measurements to okay/worrying/dangerous/deadly/catastrophic (that’ll keep them happy).

[@Quagmire1428Gaming]

looking forward to the rest of this series. keep 'em coming mate :) 👍👍👍

[@pawelcitak83]

Got interested in nuclear fission once RBMK blew and we had to take the lugol's iodine back then in 1986 (Poland) I was pissed off cause mom kept us home under really hot superb weather. Later on parents and books explained the thing to me. Your channel rocks like graphite blocks at the top of the reactor at 01:23:03 if you know what I mean :)

[@jamestracey2006]

Paweł - I see what you did there lol 😂

[@Exploited89]

The appetizer was great, now it’s time for the main course! Can’t wait 😊

[@DavidCurryFilms]

Wow, new RBMK vid 👍

[@BOBAH-HA]

The USSR scientists weren't that reckless to leave safety to a "balancing act". It was considered safe, and it had negative void coefficient, it was achieved by installing additional absorbers when the reactor is loaded with fresh fuel. They had to prove that the reactor will be safe in case of DU-800 ruprute, which is the main water pipe. Additional absorbers are being removed as fuel burns out, and when there's little to no of them, the void coefficient shifts from - to +. That was unknown at the time. Not enough study. The steam doesn't get passed to the separators, it's a water-steam mixture with ~10% of steam. They're called separators for a reason. The gas in between graphite block didn't help with heat conduction, the reactor space was filled with inert gas to prevent graphite oxidation in high temperatures. The doctrine of RBMK was that it was safe enough. They didn't consider containment because in their minds every accident that could happed could've been handeled by the reactor building structure, they had several rooms with thick walls designed to contain the radioactivity in case of piping or channel rapture. That makes sense considering it didn't had a vessel and HUGE pipings like PWR. "Massive concrete dome" simply wasn't considered as a necessary thing. And cost cutting isn't a bad thing. Why would you use something more complex and expensive, when you already have what you need now and for a cheaper price? Xenon poisoning... So many people get it wrong. Xenon is ALWAYS inside the reactor. And the level is *only starting to grow* after lowering the power, it's not just "bam, poisoned". It takes HOURS for xeon poisoning to reach its peak. The poisoning wasn't the cause of 1975 accident. The operator was able to bring the power up, but with only part of the reactor. He tried to counter hotspot, but the automatic controller negated his efforts. That's why second gen of RBMKs got more sophisticated local automatic controller. It wasn't kept secret as such. The Leningrad NPP was operated by the Ministry of Medium Machinery, when all others by the Ministry of Energy. They simply didn't cooperate, didn't have experience exchange. In Chernobyl 1 one fuel channel was raptured, parts of fuel assembly were pushed outside the channel in between the graphite blocks, deforming nearby masonry and channels. The water regulating valve of this channel was clugged by metal debris. It didn't take "almost a year", unless your year span is close to 77 days.

[@Alexander_Sepulveda]

I'm addicted to your channel

[@PlainlyDifficult]

Thank you!

[@MultiSciGeek]

My god I never even knew about this. Can you cover more near nuclear disaster incidents?

[@BlackPill-pu4vi]

Engineered ignorance of important things is a uniquely American problem. I'll wager you are compelled to know LOTS about personal pronouns, feminism, the Rainbow-Alphabet Mafia, Biden vs Trump, pro sports, and the holy never-to-be-questioned mantras against Hitler.

[@Diogenes-totes]

Haha, within a minute of posting I get to watch. Thanks m8

[@PlainlyDifficult]

Thank you!

[@burtony3]

@Richard Wagner You win the internet today for that comment!

[@pimptronic]

Great vid mate!

[@PlainlyDifficult]

Thank you

[@gateauxq4604]

‘May come ip again later’ *cackles in 1986*

[@bificommander7472]

Shut up, Fomin!

[@abc-coleaks-info]

The RBMK reactors were emphatically called “Fast Breeders”. While they took advantage of the power generation potential, the creation of plutonium was the primary purpose.

[@fixedguitar47]

Everything man has made is flawed. If it’s designed by an imperfect person it’s an imperfect machine.

[@dewittbourchier7169]

The designers of the RBMK were aware of the positive void coefficient potential. They were not idiots, which is why they had boron control rods as the other half to the graphite moderators so that lowering the control rods could slow down reactivity.

[@ExperimentIV]

oh, PD, prepare yourself for everyone posting the same 5 lines from HBO's Chernobyl ad infinitum during this series. godspeed

[@NeneExists]

The control rods weren't so much tipped with graphite as a rod of solid graphite the entire depth of the reactor, that was replaced by the control rod when it was inserted.

[@MinSredMash]

The graphite displacer was not the full length of the reactor. There was a 1.5 meter water gap at the bottom, which was why it was dangerous.

[@FerrowTheFox]

Ok, ngl that RBMK reactor face creeps me tf out xD On a more serious note: It amazes me that they had three accidents (Leningrad in 75, Chernobyl in 82 and Ignalia in 83) with RBMK reactors that showed serious design flaws and still refused to learn from or tell other operators about them.

[@PlainlyDifficult]

Unfortunately that would have involved the higher up managers admitting there was a problem!

[@bmstylee]

They were on a need to know basis. And obviously the KGB and others believed they didn't need to know.

[@HalfgildWynac]

Sort of. They did sent out a message to all RBMK power plants in 1984, three or four pages of text describing the potential danger of operation at low energy output. It is just that such correspondence was completely inadequate. That is, unless you really believe executives carefully read dozens of documents they receive every day. None of the management even remembered seeing that notice by 1986.

[@grantrennie]

Thanks for another great video 👍

[@PlainlyDifficult]

Thank you!

[@I_SuperHiro_I]

RBMK reactors do not explode....often.