pe you enjoyed the video this is a plain difficult production all videos on the channel are created common share attributioner like licensed play difficult videos are produced by me john in a sunny southeast and corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got a patreon and youtube membership account if you'd like to support the channel financially and all that's left to say is thank you for watching mining is a dangerous industry for its workers from coal dust inhalation suffocation explosions and the obvious one mine collapse a collapse on the bed of the sesquihana river in pennsylvania united states highlighted the risks to the industry posed by improper execution of safety precautions the whole created would flood an entire mine complex swallowing up 10 billion us gallons of water and take the lives of 12 miners but also would be the parting shot of the ending of the coal industry in the region northwestern pennsylvania thoratics history has been intertwined with coal mining operations and isn't the first time this area has popped up in a plain difficult video of course i'm talking about centralia but today we're over in columbia's next door neighbor lazerne county our story starts back in 1762 with the first discovery of anthracite coal in the region this particular type of coal is sought after as it has the highest carbon content the fewest impurities and the highest density of all types the wyoming valley also known as the anthracite valley is canoe shaped about 25 miles long which extends from the counties of sesquihana and wane in the north to columbia county in the south with you guessed it lazerne slap bang in the middle when you see the township of jenkins on the map in relation to the anthracite valley it's not hard to see why the town had such a strong coal industry focus so much so that a small unincorporated community would be given the name port griffiths named after one of the original stockholders of the pencil vania coal company due to a number of mining disasters in the usa by the 1950s multiple safety regulations were in force in an effort to try and put disasters like the avondale mine disaster in 1870 to the past however the economic forces of lowering coal prices meant that the industry was in a slow decline long gone had the peak output of 100 million tons in 1917 as with most dying industries companies tried to squeeze out the last few drops of profit available by willfully ignoring or bending safety regulations and using old life expired equipment a side effect of this was the safety of those the managers sent to work every day in and around the port griffiths area multiple mine owners and contractor companies operated an intricate connected maze of mine shafts along and under the seshki hannah river incorporating winter moot and monoconic islands the nox coal company was one of these operations cutting costs and responsibilities at every turn the company was a contract mining operation these organizations mined on behalf of the mine owner which allowed shall we say streamlining of operations the nox coal company had begun leasing the riverslope mine from the pennsylvania coal company in may 1954 the company hired 174 men 23 surface workers and 151 underground workers the mining operations were to exploit the pitstone and marsy veins which contained the juicy anthracite production from nox coal was around 700 tons per day which was hand transferred to chain or shaking conveyors the main workings for the company was through two entrances to the mines the riverslope and the main shaft three other shafts operated by other companies were available for emergency exit from the complex the riverslope was dug into the ground 240 feet long at an angle of around 25 degrees where intersected the pitstone vein the main shaft was 332 feet deep and the other three emergency shafts were the halt shaft at 528 feet deep the school east shaft at 579 feet and the eagle air shaft at just 60 feet the mining operations employed the chamber and pillar method which looks like this in order to get the sweet sweet coal out of the pillars a recovery method was used this involved filling the gap with waste material and then mining the pillar but this was only allowed when authorized by the landowners and can be very dangerous the mines were rather close to the sesquihana river and this necessitated some rules and regulations in regards to how close the miners could get to the riverbed the maps of the mines had things called stop lines where mining could not take place because of inadequate roof thickness this not-to-be-pass line gave a 50 feet safety margin between mine wall and river the nox coal company requested a 35 foot margin which government officials approved this wouldn't be enough and eventually the company would keep pushing the boundaries to chase the anthracite veins until the point of no return two illegally dug gangways were extended under the river 125 feet past the officially and clearly designated stop lines the workings then sharply turned up to follow the pitstone vein on january 22nd 1959 the nox coal companies disregard for rules would finally come back to bite them in the morning a team of 81 miners descended down the river slope for another day's work in the dusty mine various teams split off along the various corridors to the different seams management with the backing of the workers union had been asking the workers to dig well beyond the stop lines eventually reaching just 19 inches of the icy cold january sesquihana river some of the workers in the marsy vein were told to put down some loose roof material and put in some timber at around 11 30 a.m a timber prop cracked one of the workers informed the foreman who then went back to check the pitstone vein at 11 42 the roof gave in to the way to the river above the assistant foreman telephoned the colliery who then in turn sent out the emergency warning for everyone to evacuate the mine the call was also sent out to the adjacent mines who withdrew their workers 22 escaped through the may shaft some by the time they had made their escape had to wade through the flooding tunnels 11 men escaped via the hoitz shaft and three left via the river slope 33 made it to safety via the abandoned eagle air shaft in total 12 were trapped behind in the icy cold water below the breach had created a hole in the riverbed with millions of gallons gushing down the power of the water swept away the timber supports of various workings by the afternoon of the 22nd works were underway to fill the hole as the western railway line of the lee valley was broken and diverted to near the breakthrough this was rather strange as not only rubble and waste was to be poured into the hole but the railway carriages themselves anything that could be thrown in was including the aforementioned carriages mine carts boulders hay and any other rubble available a few days later on the 25th of January the water flow was stemmed somewhat which allowed rocks and earth to be placed in the semicircle around the hole two sinking pumps were installed in the mines to try and begin the drying process these would later be joined by another 22 shaft pumps bulkheads were placed inside the mine near the breach and above ground two cofferdams were built starting in March completing in May the same year the dams went from the shoreline to winter me island on the eastern side above and below the breach area a third dam was built on the island to completely divert the water away from the area tons of clay and rock were poured into the hole and a concrete cap was placed on top of the opening a lot of water was pumped from the flooded mines but none of the 12 missing men were ever found but as with any disaster like this we need to look at how the breach could have happened in the first place and spoiler alert it involved corruption federal mine inspections in 1958 had taken a look down the mines but no sign of any wrongdoing was found unfortunately this would be wrong inspections made by the Pennsylvania Coal Company during 1958 had actually highlighted Knox's coals passing of the stop line but no remediation action was taken it was found that Knox Coal had not only passed the line but was also working in an area that needed permission from Pennsylvania Coal which unsurprisingly was not given there was another main factor for the failure and that was the water itself due to the time of year the sesquihanna river was partially frozen over which contributed to an increased water level the higher level increased the weight on the already weakened riverbed during investigations post incident it was found that one of the labor union leaders had shares in the company which is obviously a conflict of interest as well as a blatant violation of american labor law for disaster inquiries eventually led to charges against the 11 top bosses at the Knox Coal Company the Pennsylvania Coal Company and the united mine workers of america the charges varied from manslaughter to bribery but yet again no one would actually serve prison time after numerous trials and appeals three bosses at Knox Coal did eventually serve some time but not for the deaths at the river slope but instead for tax evasion the disaster put a spotlight on the corruption and dodgy dealings with the coal industry in the region resulting in probes into other company's operations and it was found that Knox Coal was not unique but disaster accelerated the end days of deep mining of coal in the anthracite valley not only did it cause significant damage to the mines but attempts to plug the hole used up valuable equipment i kind of imagine it's similar to fixing a flat tire by throwing out the rim and replacing it with the steering wheel which needless to say is a bad idea thanks for watching i hope you enjoyed the video this video is a plainly difficult production all videos on the channel are creative commons share attribution are like licensed plainly cropped videos are produced by me john in a sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints for future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially not that's enough to say is thank you for watching when mary shelly penned frankenstein she envisioned the risks of scientific discovery as a warning for pushing the boundaries beyond what a person can take responsibility for shelly may not have realized but science would almost catch up to her just over 150 years later the experiment in today's video was something that could have been a prototype for frankenstein's monster and that is the transplant of a head from one body to another but as with many experiments involving animals there is an efficacy gray area where the lines are blurred between what is butchery and what is not the experiments covered in this video is essentially the vivisection of multiple animals and can be argued for the good and bad of scientific discovery welcome to a new series of plain difficult videos where we have a look at some of the more ethically rocky scientific experiments head transplants have fascinated doctors for a long time imagine giving a paraplegic person the chance to regain their body independence back being able to make use of a body that would otherwise be buried or cremated to give someone a new chance at a more normal life it's possibly one of the final frontiers of organ transplants a science that has brought back many from death's door today we are looking at the infamous 1917 monkey head transplant conducted by robert joseph white although the experiment sounds like the stuff of nightmares the study did help push forward experience and knowledge in organ transplants and because this is a new series we've got a new scale and that's the ethical scale 10 being legit evil and one being for the greater good of mankind as such i'm going to rate the monkey head transplant a six purely because it's so grim and i'm pretty squeamish our story starts 18 years before robert white was born and the first dog head transplantation by american physiologist dr charles guffrey and french surgeon dr alexis correll the surgery involved attaching a decapitated dog's head to another dog's neck with the blood first flowing via the donor dog's head to the live victim the experiment was a proof of concept as the donor head showed some reaction to stimulus but due to 20 minutes of blood loss during surgery the extra new head deteriorated quickly the test dog was put down shortly after the blood had started to cause brain damage and this would be the biggest hurdle to a head transplant the two doctors although arguably failing at this experiment did use their knowledge to further organ transplant science earning them a noble peace prize a few years later our next journey through the gruesome history of head transplants next stops in the 1950s and not surprisingly the soviet union with a doctor vladimir demikov in 1953 demikov made strides in coronary bypass surgery having successfully completed such experiments on four dogs that lived over two years post surgery which in all books is a success demikov turned his sights on the ultimate in surgery and obviously that's going to be head transplants in 1954 demikov achieved better results in East Germany than guffrey and carol allowing the donor dog head to be able to lap water be more aware of its surroundings and have limited movement the surgery involved grafting the upper body including front legs and head onto the other dog demikov did several experiments with multiple dogs the longest for any subject survived post surgery was 29 days but most died within a few days the process that was used preserved the blood flow to the donor head hence more functionality post surgery the limitations of survival of the dogs was mainly due to immune response of the recipient to the donor causing death the next major challenge of head transplantation involved immunity suppressive agent development enter stage right robert j white the one who would do the infamous monkey head transplant white in 1965 had started to experiment with the concept of head transplants although he focused more on isolated brain transplants and the difficulties in keeping the flow of blood he created vascular loops to preserve blood flow between the internal maxillary and internal carotid arteries of the donor dog this meant that the brain has uninterrupted blood flow even after severing the second cervical vertebrae the method was named by white as auto profusion using this method white was able to successfully graph six canine brains to the cervical vasculature of six other dogs although the surgeries were successful the dogs lived between six hours and two days post experiment using monitoring equipment implanted in the brains showed good oxygen and glucose consumption meaning they had a good metabolic state post surgery the experiment showed the feasibility of short term isolated brain transplant although pretty gruesome the methods learned meant white could attempt a monkey head transplant on the 14th of march 1970 white would conduct his experiment for the experiment white accepted that like all other head transplants to date but the donor body would be paralyzed because of this the isolated body would have to be kept in function by mechanical and chemical stimulation of the heart and lungs this was due to the complexity of re-establishing the nerve stem but the main goal was to keep the brain function to a similar level post op to pre op whites experiment used eight small rhesus monkeys for a total of four experiments each of the four experiments would have monkey a's head attached to monkey b's body the experiment used whites auto profusion technique and reattachment surgery which had been perfected in the lead up to 1970 the operating room team even used marks on the ground to choreograph each and every move of everyone in the theater the rhesus monkey was chosen because the animal would give the most accurate representation of a human like central nervous system the monkeys way between six and seven pounds were initially put under intravenous pentobarbital then each head for transplant was instrumented with EEG's and the recipient bodies were instrumented with ECG once this was completed the monkeys were tracheotomized and was servically transected at the level of the fourth and fifth cerebral vertebrae at the same time preserving the carotid jugular circulations the preservation of blood flow was done through sutured can your loops during previous experiments it was found that just one carotid artery and jugular vein was enough to provide blood flow for the head even after all other circulatory support have been severed this was completed under constant monitoring for the transplant to the new body one the cannula loops was stopped and connected to the body and after blood flow was resumed the second cannula was stopped and connected to the new body this allowed constant blood flow to the brain extra blood had been drawn from other monkeys in case of any hemorrhaging during the surgery antibiotics were under constant supply along with immune suppressive agents to help prevent rejection of the new body head combination three to four hours post surgery the monkey heads would start to show awareness of their surroundings with their eyes following stimulus and would even attempt to eat any food placed in the mouth the EEG records reflected that the establishment of a characteristic consciousness state and in a grim way the faces as seen here look rather scared of the situation which obviously is understandable if blood pressure fell so did the heads awareness a dye was used to mark the blood brain barrier the muscles in the face were active and looked like they were working as they should in fact looking at the footage you wouldn't even think that the head had been amputated the bodies did not show signs of rejection of their new heads probably because the amount of drugs pumped into the bodies each of the four experiments lived between six and 36 hours post surgery eventually the mixture of drugs and blood loss from the amputation area killed off each monkey after the experiment each brain was dissected and showed no signs of brain damage or dye infiltration proving the concept of a head transplant the monkey head surgery showed that cephalic or full body transplant was possible and even though the longest of any of the monkey's lives was just over a day with extra time taken on suturing with modern techniques of today the surgery could have been a much more longer term experiment white became well known after the experiments and took a lot of flak from animal rights groups and even his peers although it did not seem to really affect his accomplishments as a neurosurgeon who within his career perform over 10,000 surgeries albeit on human subjects he would pass away in 2010 at the age of 84 the lessons learned from the experiments helped further transplant science which by the 1990s had more improved mixtures of immunosuppressive agents which had hindered the monkey's life expectancy post surgery in 1970 the new drugs were a key factor when the first human face graft proved successful head transplants did not die with whites however as the mantle was taken up by Xiaoping Ren who grafted the head of a mouse onto another mouse's body which survived the six months post surgery and in 2013 Sergio Canavero published a method that he said would make a human head transplant possible by 2017 but that never happened so take that with a pinch of salt where would you rate the monkey head experiments on my ethical scale one being it's all good and ten being the work of pure nightmares thank you for watching this is a bit of a new subject choice for me and a pilot of sorts of a new series would you like to see more videos like this then let me know in the comments below play the cool videos are creative commons attribution share alike licensed and are made by me john inner not at the moment so sunny corner of southeast in london you can check me out on twitter for odds and sods and for those of you want to give me any money you can at patreon youtube membership or paypal and all that's left to say is thank you for watching before we start i should probably say that this video is based off the joint accident investigation commission's report into the incident there has been subsequent theories into the cause of the disaster stemming from more recent discovery of a hole in the ship's starboard side of its hull and more modern 3d scanning of the vessel's resting place the theories have surmised that the cause could have been an explosion or even a collision with a submarine right without disclaimer out of the way here's the video ships are truly impressive pieces of engineering defiantly navigating the immeasurable power of the sea when you are near one on land the vast size of such machines gives the impression that such a large structure of steel would be unsinkable but as history has proven this is most certainly not the case and a cruel merciless sea can swallow such vessels and hundreds of lives aboard the sinking of the estonia would be the third worst loss of life at sea on board an european ship during peacetime only being beaten by the rms titanic and rms empress of ireland there is one major difference that sets the estonia aside however and that is that she didn't collide with another ship or iceberg but instead the power of the waves themselves caused a major failure of one of her components that allowed her to operate as a car ferry on the 28th of september 1994 within an hour over 15 000 tons and 852 lives would be lost beneath the waves of the Baltic sea today we're going to rate this disaster here five on my patented essentially now arbitrary plainly difficult disaster scale our story may end in 1994 but it began all the way back in 1979 and the need for a new vessel for the rapidly expanding ferry industry in the Baltic sea a contract was signed for a new ferry on the 11th of september 1979 and was set to be built by mayer werft in paperburg germany the ship which had her killed late in october 1979 was to be built to similar specifications of the diana 2 in order to speed up construction by using a similar design her story was turbulent from the start after the original customer a norwegian shipping company led by parley augustin pulled out of the contract luckily ruderi ab sally one of the partners in the viking line consortium was more than happy to take over the project the new ship was recalled the viking sally the name stonia came along later on in her operating life as part of the new owner specifications the length of the ship was extended from 137 meters to 155 meters and along with this came a new superstructure design one such design feature from the diana 2 that was retained was a hinged bow visor that opened upwards enabling vehicle access to the car deck various parts of the ship were built by different contractors however the vital bow visor was installed by mayer von tell ab was the supplier of the visor parts used to lock and operate the machinery the machinery was actually manufactured by another company grimoire's verxtad's ab and all details communication and changes were made through von tell as the middleman the bureau very test rules gave no detailed guidance for calculations for the visor from vertical and longitudinal sea loads and as such von tell and mayer used their own estimations and it is unknown if the two companies compared notes the visor including attachment devices was built of grade a mild carbon steel and was set up in a way that meant the visor couldn't be operated unless the ramp was fully closed the visor pivoted around two hinges on the upper deck and was locked in place by three hydraulically operated devices which were two side mounted and one bottom mounted and it also had two manual locking devices she had a passenger capacity of around 2000 people maximum service speed of 21 knots maximum deadweight draft of 3006 deadweight tons and four man engines creating a combined power of around 23,000 horsepower the ship was built to the rules and regulations of the finished maritime administration the Viking Sally was pressed into service between turku and marinham in finland and stockhome like most ships the Sally had its share of screw-ups including a couple of murders propeller issues and the grounding her owners radiri ab Sally were experiencing financial difficulties towards the end of the 80s and were sold to the Finnish swedish group F John but still operated under the Viking line under her original name she did fully come under the control of her new owners in 1990 when she was painted in Celia lines colors renamed the Celia star but remained on the same route the new name would only last a year or so until she was transferred to the wasa line another subsidiary of the F John group and was placed in the wasa line operation in the Gulf of Bothnia for the new operations she was now called the wasa king in 1991 that was until the 14th of january 1993 when she would change flags from Finland which she was originally delivered to the flag of Estonia this coincided with a new owner the esteline marine company limited and a new name the ms Estonia she was pressed into service on the Tallinn Stockholm route at the time she was the largest ship in the Estonia national fleet and became a symbol somewhat of the country's independence after the dissolution of the eastern block right that leads us to 1994 and the Estonia departing from Tallinn on the 27th of september 1994 at 7 15 p.m for a scheduled voyage to Stockholm and her estimated time arrival was 9 a.m on the 28th of september she carried 989 people 803 of whom were passengers leading to remaining 186 being crew upon clearing the harbour all four engines were powered up for full speed and she began her journey sea conditions along the Estonian coast were moderate but became worse when she joined the open waters the weather continued to worsen with winds increasing to 15 to 20 meters a second causing two to four meter high waves which crashed across the Estonia's bow as the ship got thrashed around some passengers became seasick at around 25 past 12 in the morning and at a speed of about 14 knots the vessel encountered the crashing on her port bow at around one o'clock in the morning a metallic bang from the bow area as the vessel hit a heavy wave was heard from the car deck by a member of the crew the crew member informed the bridge of the strange noise after inspecting the indicator lamps all seemed well the ship did not slow down after the report and the crew on deck didn't make use of a cctv link to the car deck to investigate the area of the loud bang roughly about the same time a shift changeover happened on the bridge and soon after another report of a loud metallic bang from the bow came in at around 105 the seaman of the watch was sent down again to inspect the visor but just 10 minutes later the visor separated from the bow and tilted over the stern the ramp was pulled open allowing water to surge into the car deck the water caused a heavy starboard list and at the same time dramatically slowing the ship down estonia's distress beacons had to be activated manually which the crew failed to release throughout the ship panic set in amongst the passengers with many attempting to rush up the staircases although many were still trapped inside their cabins life jackets were distributed to passengers who managed to reach the boat deck some jumped or were swept into the sea and a few made it onto life rafts that had been launched due to the list of the ship lifeboats can be deployed and at around 1.20 in the morning a fake pa announcement saying alarm alarm there is alarm on the ship was broadcast at 1.22 the first mayday call from estonia was sent and a general alarm to crew for lifeboats was announced by 1.24 multiple radio stations on both ship and land received the calls around the same time the four engines stopped running causing a backup generator to power up but this left much of the ship unlit further adding to the panic flooding of the accommodation happened at an alarming speed and the starboard side of the ship was submerged at around 1.30 as the ship continued to flood the list increased to 90 degrees as she sank beneath the waves the stern went first disappearing from radar in the area at around 1.50 the location was about 22 nautical miles from uto island finland within the hour four passenger ferries had arrived on the scene of the accident and started to search out and rescue survivors it wouldn't be for over an hour before vital helicopter support would arrive the mounting efforts rescued 138 people from the waters throughout the night and early morning of the 28th of september after the living the remaining search efforts found 94 bodies over the next few days with such a tragic loss of life and the sinking of a thought to be reliable and safe vessel investigators were faced with the question how did the estonia sink most of the victims went down with the ship to the seabed she was found in international waters on the 30th of september within finland search and rescue region resting on the seabed at a water depth of around 80 meters it was vital that the cause of the sinking be found as the estonia was one of many similar ships operating in the region with reports of noise from the bow visor hinting at a failure point a remotely operated vehicle survey was decided on to ascertain the ship's general condition and whether the bow visor had become detached during early october the rov made several videotapes of the wreck and the results were shocking during investigation into the sinking it was found that the bow visor and ramp had been torn off as it failed to resist the power of the waves hitting against it the first metallic bang heard around one o'clock in the morning was thought to have been the sound of the visor's lower locking mechanism failing and other reported noises were the visor flapping against a hole as the other locks failed as a cruel twist of fate an amounting bracket for the locking bolt position sensors appeared to be undamaged this meant that even after failure there was no warning to the bridge of the now open visor this was even more compounded by the design of the bridge which was too low to have a line of sight to the visor meaning there was no way of seeing the state of the visor even after the catastrophic failure during investigation another incident a year before was highlighted which would have been a vital warning sign in 1993 the diana 2 of stonia's kind of sister ship had experienced a visor locking failure as the starboard locking device lug was lost the bottom lock was bent with its welds cracked and the port side locking device lug was bent with its weld also cracked she was repaired and the incident was not considered serious enough to need a general notice via the bureau veritas regional office in gothenberg the investigation concluded that the visor was insufficiently designed to withstand realistic load levels this was due to limited experience of the industry to hydrodynamic loads on bale visors because of this both the shipyards and the equipment supply used their own and flawed calculations the full width open car deck contributed to the rapid increase in list when flooded which resulted in the estonia's capsizing and sinking the action of the crew speeded up the ship's demise if they had used the cctv link to the car deck they would have been able to see the water rapidly flooding in this coupled with the slowing down of the speed of the ship after reports of strange sounds could have slowed or even prevented the sinking soundingly alarm aboard the ship and the seemingly lack of direction of the crew was highlighted by the investigators and was thought to be a contributing factor of the panic by the passengers the loss of the estonia held a mirror up to the shipping industry in the region necessitating new vessels from 2010 to be able to withstand their car deck being flooded up to 50 centimeters all ships post accidents had to be modified to release their emergency beacons automatically and life raft regulations for rescue from listing ships in rough water were introduced but that is little consolation to the 852 that lost their lives that september night thanks for watching i hope you enjoyed the video this video is a plain difficult production all videos on the channel are creative commons attribution share like licensed plain difficult videos are produced by me john in a sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially all that's left to say is thank you for watching 1986 is the year that would change everything in the nuclear industry a disaster would burn the concept of atomic fallout into the zeitgeist of the 1980s and the legacy would act as a constant reminder of the risks of improper management of a nuclear reactor the disaster became a testament on how poor design and mismanagement when placed in a venn diagram can equal a radiating most of eastern europe of course today we are looking at the chenobyl disaster of 1986 and this one has earned the magical 10 on my painted plain difficult disaster scale believe it or not this video is actually part of a series of videos on the chenobyl disaster and in a wider context the rbmk reactor type and in light of that it might be worth checking out my video on the leningrad and other chenobyl meltdown don't worry i'll still be here when you get back ah you're back welcome yep i know it was a bit of an overdone trope so let's get back to the main reason why you're here our story starts back in 1970 and in ukraine about 100 kilometers 62 miles from Kiev when ground was broken for a new city that would become known as pripyat an atom grad that was designed to house the workers for a new nuclear plant it should be said that the original plans were to build the city and the plant just 25 kilometers or 16 miles from Kiev but it was thought to be too close to a major city which turned out to be a good decision the concept of an atom grad is similar to say tombsk which were closed cities although pripyat was open later on in its short lifetime as a city these municipalities were designed to be self-contained communities that had a sole purpose and that was keeping the power plant working and by extension the workers that were employed there happy the community at pripyat was developed to be the perfect home for a young family with its amusement park and modern at the time architecture in the same year the ground where the new plant would exist was prepared for construction the chenobal nuclear power plant began construction proper in 1972 after the central government decides on what type of reactors the site would house originally the idea for a pressurized water reactor was thought to suit the new plant but it was overruled by ala tolly alexandrov the chief scientist who was at the time supervisor of the project of rbmk reactor plants the reactor type was preferred due to the design being cheaper to produce and as we found out with leningrad that cost was a pretty high priority some might say even over safety the nuclear power plant had the first of its four reactors ready to operate in 1977 followed by number two in 1978 as a quick side note units one and two were the first generation rbmk 1000 reactors and because of this they had slightly different core loadings and containment structures but the remaining two reactors at chenobal were of a slightly more modern second generation and they were named units three and four which went online in 1981 and 1983 respectively there were plans for another two units but these were abandoned after 1988 when risks of contamination left the project untenable the nameplate capacity of chenobal nuclear power plant was unit one at 800 megawatts of electricity unit two at 1000 megawatts of electricity unit three also had a thousand watts of electricity and the same with unit four in this video i'll be focusing on the second generation rbmk its design and more specifically unit four but i did look into the first generation in the leningrad video the rbmk was a bit of a unique design in the reactor world but it was a product of evolution rather than revolution in that it used graphite to moderate the chain reaction with light water as a coolant this combination allowed it to use low enrichment uranium 235 for fuel which is not surprisingly significantly cheaper than other reactor designs the rbmk had a very large core region consisting of a height of seven meters and a diameter of 11.8 meters which was mounted in a steel cylinder that was placed on top of a biological shield the steel cylinder was 16 millimeters thick and had a diameter of 14.52 meters by a height of 9.75 meters dug into the floor of the reactor building inside a reinforced concrete line pit between the steel wall and the concrete lining a water tank was placed followed by a sand packing below the bottom biological shield there were several basements used for pipe work for the reactor core cooling loops the core consisted of graphite blocks sized 25 by 25 centimeters stacked up with holes drilled through the center for fuel and control channels the size of the core could issues in reactivity control during operation but we will talk about that a bit later on on top of the core another biological shield was placed with a steel cover on top of it which formed the floor of the reactor hall the cover plate was capable of withstanding a pressure buildup resulting from steam released by two simultaneous channel ruptures all of this allowed the design to be refueled whilst in operation which again helped with costs by reducing downtime as a side effect of this the confinement structure of rbmk reactors is less than ideal as the tall refueling machine had to be housed inside the reactor hall because of the large floor space and subsequent roof requirements meant that the vast quantities of heavy concrete wouldn't have been architecturally or more importantly financially viable the rbmk didn't have a prototype and was instead put straight into production with the first reactor being installed in leningrad in 1970 the original designs omitted confinement instead claiming that the fuel being in its own channel with flowing cooling water was an acceptable alternative the main takeaway from this is confinement was poor resulting in disastrous results in the case of efficient product release the coolant was pumped through the core from the bottom common header through high pressure tube that jacketed the fuel elements where the water would boil coolant water also circulated in the control rod channels the primary cooling of the reactor was via two separate cooling circuits one of each for half of the core meaning everything was doubled up leading to four main circulating pumps which were three operating and one standby per loop as the coolant boils it exits the top of the core and is passed through a water steam separator which takes the steam to a high then low pressure turbines which generate electricity the steam is then passed through a condenser that turns it back into water to be pumped back into the core completing the primary cooling circuit the condenser is called by using a separate secondary water cooling circuit meaning the primary cooling circuit is self-contained as mentioned before the reactor employed graphite blocks for its moderator now moderator is used to reduce the speed of fast neutrons released from fission so they can better facilitate a chain reaction getting more use out of the fuel ideally moderators work without capturing any neutrons leaving them as thermal neutrons the way the design has its potential flaw is having a separate coolant that can also absorb neutrons which can make the reactor unstable in certain situations this brings up the big elephant in the room and that is void coefficient you see it wasn't just a graphite that had moderation characteristics but the coolant water as well because h2o naturally slows down and absorbs neutrons this brings a problem for the reactor as with the increase in temperature from fission the coolant boils off into steam known as voids i.e a bubble that does not absorb neutrons with the steam not absorbing neutrons this leads to an increase in the power of the reactor the rbmk did not rely solely on its coolant for moderation because that's what the graphite was for but the water did absorb neutrons meaning that as it boiled off the operators had to compensate for this with the control system if not properly managed an incident of a runaway can happen as the coolant heats up increasing reactivity heating up the coolant more creating more steam leading to greater reactivity and this is called a feedback loop due to its reactor state more and more neutrons are produced and their density grows exponentially fast creating a positive void coefficient the risks of a feedback loop were greater at certain power levels but this will be covered later on the design relied heavily on the void coefficient for its reactivity this is unlike a pwr setup in which the coolant is also the sole moderator meaning the chain reaction can't be sustained if all the coolant has boiled off creating a more stable design but this is also much more expensive now this leads us quite neatly on to reactor control as i said before the core region was rather big and this meant that the rbmk was kind of like multiple smaller reactors in that hot spots could occur which needed to be individually managed and this leads on to the strange design choice for both top loaded and bottom loaded control rods there were 167 top loaded rods and 32 shortened rods loaded via the bottom and another 12 automatic controls inserted from the top the shortened rods were used to manage axial power distribution which was necessary due to the core size to manage hot spots the main control rods had a 4.5 meter long graphite rod termed a displacer attached to the end of the length for the control rods except for the 12 rods that we use in automatic control the displacer connected to its rod via a telescope with a water filled space of 1.25 meters separating the displacer and absorbing rod this was to stop water filling the space left behind by the control rod after it has left the core region which would parasitically absorb neutrons because removing one neutron absorber in the form of a boron control rod to be replaced by another neutron absorber albeit weaker in the form of h2o kind of defeats the point of the control rod thus if there was no displacer then more control rods would be needed as each one would have less of an effect on the reactivity of the core the dimensions of the rod and displacer were that when the control rod was fully extracted the displacer sat centrally within the fueled region of the core with 1.25 meters of water at either end but this set up in certain situations could cause a positive scram effect on receipt of a scram signal causing a fully withdrawn rod to fall water was displaced from the lower part of the channel as the rod moved downwards this caused a localized insertion of positive reactivity in the lower part of the core this was because the rbmk had a high moderated to fuel ratio meaning the lower part of the core would experience a spike in reactivity as the graphite displacer entered it as it replaced the neutron absorbing water with a neutron moderating graphite but this situation was only dangerous at certain power levels of the reactor which was meant to be mitigated by the knowledge and training of the operators and also importantly by their management part of this mitigation was by having an operating reactivity margin the orm is the number of equivalent control rods of nominal worth remaining in the core the total time required for a scram or insertion of the emergency control rods into the core when starting from the upper limit stop switches was around 18 seconds which was relatively slow but this was due to the size of the control rod channels and the fact that the coolant had to be pushed out of the way the scram could be initiated by the control system or manually via the az 5 button the control system employed on the rbmk 1000 utilized ionizing chambers and various sensors both inside the core and outside which were effective from power levels above 10 percent of total power the external detectors were all mounted mid level of the core meaning no low actual power monitoring could be undertaken this meant that low power operation below 10 percent had to be done by the operators relying on experience and feel than monitoring the equipment but manual low power control was only really intended for a cold startup so to speak when the reactor was free of the neutron absorbing poison zenon 135 right i need to mention about neutron poison as it will play a vital part later on and was also a contributory factor in another rbmk incident the meltdown in leningrad in 1975 during fission some products are given off one of which is zenon 135 which has a high neutron absorption rate which is okay when the reactor is in a steady state as it burns off this undesired byproduct as poison burning is proportional to reactor power but when the power of the reactor is decreased the zenon 135 is not burned off and can shut down the chain reaction by absorbing too many neutrons this is known as an iodine pit all is not lost as zenon 135 has a relatively short half-life of around 9.2 hours so reactor core is considered poison free after several half-lives have passed but this is not good from an economic standpoint as the unit would be shut down for a few days which is where good management is meant to come into effect where safety is prioritized over money but in the form of ussr taking a reactor out of action for a few days could have a detrimental effect on one's career longevity our story starts with an issue inherent to all reactors of any type a thing called decay heat you see reactors produce heat from fission which is used to create steam to drive the turbines for electrical power some of this power is taken to drive the electronically operated coolant pumps which keep the coolant flowing through the core the reactor needs around 28 000 litres per hour during full power operation some heat is produced not directly from fission but instead from the products produced from the chain reaction and this is known as decay heat and when the reaction stops this continues at least for a while after shutdown during power operation this is fine as electricity is being produced but after shutdown the pumps need to keep circulating to remove the decay heat usually electricity needed for the pumps can be drawn from the national grid but what about if there is a full power outage then backup is needed this presents a problem if for any reason being scheduled or not a reactor is shut down and there is a power cut how will the pumps keep working well the solution is pretty simple and that is a diesel backup generator each of Chernobyl's reactors had three backup diesel generators which took in excess of 70 seconds to reach full power too much time in the event of a full power cut in theory some of this time could be covered by the spool down of the turbo generators which was theorised to cover around 45 seconds not the full time needed but possibly enough to prevent fuel melting to prove that this could work it had to be tested out and in 1982 1984 and 1985 this was attempted but all tests failed to produce the electricity needed to run the pumps the test was to be conducted again in April 1986 strangely the test procedure that was written hadn't taken into account the eccentricities of the rbmk reactor especially at low power outputs the test was to be conducted during a routine shutdown but the test to go ahead some vital systems had to be switched off most notably the active passive emergency cooling system used in a loss of cooling accident this required the chief engineer to sign it off in preparation for the test the following had to be set up the reactor power was to be reduced to between 700 and 1000 megawatts of thermal energy and the steam turbine generator was to be at normal operating speed after all this was sorted the preparations for the electrical test could go ahead the steam supply to the turbine generator would be closed off the turbine generator performance would then be monitored to see if it could bridge the power for coolant pumps until the emergency diesel generators took over when the emergency generators supply electrical power the turbine generator will be allowed to continue freewheeling down the normal plan shutdown procedure of the reactor was then to be completed the date of the test was to be the 25th of April 1986 15 minutes past 2 p.m completed by the day shift as such the operators were briefed on the procedure and a team of electrical engineers was present at around 1 a.m on the 25th of April the reactor was gradually powered down to around 50% in time for the day shift at 105 p.m the turbo generator tg7 was switched off the four main circulating pumps two electrical feed water pumps and other electrical equipment that was connected with this turbo generator were switched over to bus bars for the turbo generator tg8 the eccs was disabled with the correct authorization from the chief engineer but just after 2 p.m the Kiev electrical controller asked for the test to be postponed to cover the evening electrical peak demand the request was due to another power station in the region unexpectedly going offline genobals director agreed and the test was pushed back but the eccs was not reinstated the status of the eccs showed the lack of safety culture at the plant although the system wouldn't really be a factor in the disaster it highlights the management culture at the time the day shift soon gave way to the evening shift which in turn was soon to be replaced by the night shift to oversee the test annatoly dyatlov deputy chief engineer took the helm in the control room due to his seniority he outranked all operational staff on shift at the time alexander akimov was the chief of the night shift and lenid topchnov was the operator responsible for the reactor's operational regimen and the movement of the control rods at around 2300 hours the Kiev electrical controller allowed the continuation of the reactor shutdown and by 10 past 2300 hours the reactor power was brought down to 700 megawatts of thermal energy the night shift operators had to prepare for the test in a short period of time inferior to the test was completed the team would have a straightforward night just monitoring the decay heat until the next crew change over as the power dropped off the high amounts of iodine 135 decayed into the poison xenon 135 as it was not being burned off quick enough this produced the power of the reactor without any operator intervention to 500 megawatts of thermal energy at which point manual intervention was started in order to maintain the level at 28 minutes past 12 on the 26th of april the reactor power had dropped to just 30 megawatts of thermal energy with a near shutdown like state it is not 100% known why but both equipment failure and operator error have been attributed to the reactor state as set out in the operating instructions the reactor should have been powered down to wait for the xenon 135 to decay but shutting down the reactor without doing the test wouldn't have made many friends in management to increase the power the control rods began to be removed to try and overcome the poisoning of the core reduced coolant void and graphite cooldown in the attempts to raise the power the operational reactivity margin was violated by removing more of the absorbing control rods and by 1 a.m around 200 megawatts of thermal energy was reached the reactor was now in a dangerous state not wanting to leave empty handed diatlov insisted that the test be conducted at the current power level in reality the core was heavily poisoned and was in a dangerous state with very few absorbing rods for emergency control during the preparations of the test the operators powered up the two backup coolant pumps leading to all eight working the increase in water flow reduced the voids within the core which would have set off an automatic scram but this was bypassed by the operators as the coolant absorbed the neutrons in the core only eight control rods were left as a safety margin the minimum that the orm stipulated was that around 28 rods should have been in the core the reactor started to experience a feedback loop with not many rods in the core to manage the power the situation was that the water in the reactor found itself being the main neutral absorber and disaster was just waiting to happen at 1.23 in the morning the actual test had now begun the command given to stop the valves for turbine number eight closed and the rundown operation started as the turbines spooled down the power to the feed water pump slowed increasing the temperature of the coolant creating more voids with less water absorbing neutrons the power of the reactor began to rise a feedback loop was beginning to start in the lower part of the reactor core the operators pressed the az5 button in response to the worrying increase in power and the control rods started their travel into the reactor core as the control rod attached graphite displaces moved down to the lower part of the core in their control channels the neutron absorbing water was pushed out of the way creating a momentary spike in power replacing it with neutron moderating graphite during the spike some of the fuel rods ruptured blocking the control columns stopping the control rods at 1.3 insertion this left the graphite water displaces stuck in the lower part of the core increasing the runaway power excursion within three seconds the reactor power rose to 530 megawatts of thermal energy in the control room a few shocks were felt and the control rod indicators showed that the insertion had stopped as the channel pipes began to rupture mass steam generation occurred as a result of depressurization of the reactor cooling circuit bission materials leaked into the coolant and steam pressure grew inside the core as the coolant boiled off creating a greater neutron population the reactor power hit 30 000 megawatts of thermal energy although it is thought that the power could have gone much higher than that during the excursion the steam blew off the top steel cover and top biological shield of the reactor as more than the two design fuel channels failed releasing debris into the reactor building this was what would later be described as the first explosion but it would not be the last a second more powerful explosion occurred between two and three seconds later and this destroyed the roof and ejected super heated pieces of graphite out of the reactor hall peppering the area around the building with shrapnel some red hot material fell onto the roof of the machine hall and started a fire it is thought that around 25 percent of the core material was ejected but now uncovered reactor core mixed with the outside air and ignited a graphite fire a blue glow could be seen outside the reactor building from ionizing radiation emitting from unit four there was nothing left at the reactor confinement structure which meant little stopped the harmful contamination from escaping some of the debris that was ejected started a fire on the roof of reactor 3's building but insanely the unit wasn't shut down straight away instead the operators were told to take iodine tablets and don't respirators at 1.45 in the morning the first responders from the Chernobyl fire team arrived under the command of lieutenant vladimir previc and began trying to extinguish the flames on unit 3's roof all around them laid pieces of unit four's graphite core the firefighters were only aware of the fire and because of this they didn't have any radiological protective clothing on as they worked they breathed in some of the fission material in the form of dust and were exposed to the deadly radiation many would come down with acute radiation sickness shortly after some of the first responders fell to metallic taste in their mouths similar to what others had reported post exposure for example from the victim of the wood river junction criticality the fires on the roofs of units three and four were under control between 10 past two and 20 past two in the morning and the fire was fully put out at five o'clock in the morning having a graphite fire in what was once unit four continue to burn expelling its radioactive plume of dust steam and smoke into the atmosphere the operator started to pump water into the core but this did little to bring the situation under control the estimated dose of five to six runkins per second was experienced around some parts of the reactor building which is equivalent to more than 20,000 runkins per hour which is enough to give you a lethal dose in minutes the effective dose to meter monitoring of the operators was unavailable when the two 1,000 runkin per second capable meters were inoperable the only remaining meters maxed out at 0.001 runkins per second which immediately read off the scale when used meaning that no one in the control room actually knew what they had received the poor awareness of the dangers they were in left the operators believing that the core was still intact crew chief alexandra akimov stayed in the building until the morning ordering staff to try and pump water into the core many of these workers would be dead within a few weeks you see the rbmk core was generally fought by staff to be incapable of becoming uncovered and as such the blatant evidence to the opposite was ignored at 2 pm on the 26th of April an announcement that you would never want to hear was broadcast in the city of propiette for the attention of the residents of propiette the city council informs you that due to the accident at the chenobal power station in the city of propiette the radioactive conditions in the vicinity are deteriorating the communist party its officials and the armed forces are taking necessary steps to combat this nevertheless with the view to keep people safe and as healthy as possible the children being top priority we need to temporarily evacuate the citizens in the nearest towns of Kiev region for those reasons starting from the 27th of April 1986 at 2 pm each apartment block will be able to have a bus at its disposal supervised by police and city officials the first to leave the town was women and children and within three hours the city was empty a ghost town and left to decay but this will be a subject of another video emergency accident management operation began on the 28th of April the first priority was to try and tackle the radioactive material release the first attempts were to try and put out the graphite fire to try and put out the fire multiple items were to be dropped into the core each item that was to be dropped over the core was intended to tackle each different part of the fire and the radioactive release first the radiological side was tackled by dumping a total of 5000 tons including about 40 tons of boron carbide 2400 tons of lead and 1800 tons of sand clay and 800 tons of dolomite the method of deployment was to be via helicopter initially the first pilots received high doses as they hovered above the uncovered core the pilots were then ordered to fly over the core dumping during the flight which reduced pilot exposure but reduced the effectiveness of each sortie and had the side effect of damaging the remaining structures and actually spread the contamination even more in total 1800 sorties were flown they didn't do much and even worked as a thermal insulator increasing the fuel damage Boris Trebina became the soviet crisis management supervisor and Valery Legazov from the Kurchatov Institute of Atomic Energy became a key advisor of the government commission formed to investigate the cause of the disaster and to plan the mitigation of its consequences initially the soviet government wanted to not make the disaster public but that couldn't stay a secret for long radiation alarms were set off all over europe and unsurprisingly questions were beginning to be asked at around the same time as the helicopters were dumping material on the reactor the USSR officially admitted to an incident at Chernobyl at around 9 p.m a 22nd broadcast the first of its type was announced the firefighting efforts and pumping of coolant water left the basement flooded which caused another potential disastrous outcome another steam explosion you see the fuel from the core was melting towards the basement which had flooded but below that was more water from the bubbler pools which was a large water reservoir for the emergency cooling pumps and as a pressure suppression system needed to say that this was the next point of focus for the accident management team engineers Alexei Ananikov and Valery Bezpolov and supervisor Boris Baranov volunteered to empty the bubbler pools this was done by valves controlling sluice gates which were housed in a room that had now become flooded all three men donned protective suits and breathing equipment and made their way down the corridor the men were successful and the bubbler pools began to empty surprisingly all three survived not only the day but continued to live long after the disaster averting the immediate steam explosion but that wasn't the end to the worry of a deadly explosion as described in the film china syndrome the core could continue to melt through the floor of the containment and into the earth eventually hitting the water table meaning another steam explosion the next focus of the accident management team was stopping the molten core from escaping the bottom of the reactor basement a design that was fought up by physicist Leonard Bolshov that involved digging out a cavity below the reactor building basement the concept used coiled formation of pipes cooled with water and covered on top with a thermally conductive graphite layer the graphite cooling plate was to be encapsulated between two sacrificial concrete layers each one a meter thick in theory as the molten uranium oxide hit the graphite it was to rapidly cool down catching the core meltdown thankfully the theory didn't have to be put into practice as the core had finally come to rest in one of the lower basements of the reactor building part of which formed the famous elephants foot which was discovered in December 1986 which had a reactivity of 8,000 runcans or 80 grays per hour for reference a whole body dose of around five grays can be lethal the molten material is known as corium and is a mixture of the material found inside the core and is mainly made up of silicon dark side with traces of uranium graphite zirconium and titanium the excavated cavity and cooling system now unneeded was filled with concrete to help the structural integrity of the heavily damaged reactor building a plan was conceived to contain the contamination release of unit four in the form of a concrete lid which would come to be known as the sarcophagus construction began in May 1986 24 days after the disaster to encapsulate some 200 tons of radioactive corium 30 tons of highly contaminated dust and 16 tons of uranium and plutonium the construction would last for 206 days between June to late November of the same year but before the core could be enclosed under sarcophagus the next phase of remediation was to remove all the core material that scattered the area and one of the most dangerous places was the roofs of the building surrounding unit four initially robots were thought to be able to undertake the clearing works but due to radiation interference only around 10% of the debris could be recovered this necessitated the use of good old-fashioned people the most basic of equipment was needed for the task which included protective clothing and a shovel a toast of 5000 people known as liquidators were called upon to undertake the cleanup on the roof each only being allowed between 45 to 90 seconds of total working time to reduce the risk of exposure the calculated risk was 25 rem or 250 millisieverts of radiation per person there were many more liquidators also used for other clearing up works in the wider area and finally after this the sarcophagus could be closed over the turbine hall and reactor building the construction was undertaken over eight stages all whilst unit four released contamination and next to unit three was still needed to be operable concrete containment walls were built around unit four and a dividing was erected between it and unit three the sarcophagus was placed on top of the concrete containment walls more than 400 000 cubic meters of concrete and 7300 tons of metal were used during the construction of the sarcophagus the building encapsulated an estimated 740 000 cubic meters of heavily contaminated debris together with contaminated soil holes were installed in the structure to allow pressure release albeit through a filtration system the shelf life of the structure was only thought to be around 20 to 30 years necessitating a new containment structure but this will probably be covered in the next video in this series so with an official death toll of 31 a nuclear power plant essentially unusable and many decades ahead of remediation works how was unit four allowed to be operated in such a dangerous state unsurprisingly it comes down to management the warning signs of the potential for fuel damage in an rbmk 1000 reactor reared their heads several times the reactor types history a partial fuel melting in leningrad over 10 years before in 1975 had been covered up and information was not passed on to other rbmk operational staff at different power plants again the fuel melting incident that happened in 1982 at chenobu unit one no less was also covered up this time by victor brookanov meaning lessons again were not passed on the risks of a positive effect of scram causing a power spike were known in december 1983 at ignalia unit one unlike other incidents involving rbmk's the information from the event was passed on to other plants but were thought to have not been important enough to act on as the control rods didn't get stuck and did continue to stop the reaction the iaa was involved in the investigation into the disaster using the international nuclear safety advisory group which had been created by the iaa in 1985 all of the reports have never been able to categorically say for 100 percent what the cause of the core uncovering was and there is much speculation to whether the power excursion happened pre or post scram but operating the reactor in the state it was in meant that something was going to fail regardless of the inherent floor designs of the rbmk it was operated way out of the agree parameters even set by the lax soviet nuclear industry it can be attributed to the culture of working where failure was not accepted and vital operating incidents were not learned from as well as this the design floors were outright covered up and held back from the operators in 1987 a criminal trial was brought against five plant employees between the 7th and 30th of july in a temporary courtroom set up in the house of culture in the city of chenoble ukraine they were deputy chief engineer anatoly diatlov chenoble plant director victor brookanov the former chief engineer nicolai m fomin the shift director of reactor four boris rogozin and chief of reactor four alexander kovilenko three other men alexander akimov lenid topchenov and velary peber vizienko would have been tried as well but the cases were dropped after their deaths due to radiation exposure they were all found guilty of varying charges from criminal mismanagement of potentially explosive enterprises to negligence receiving between 10 and 2 years amongst them diatlov who was in charge during the test was given 10 years would only serve a fraction of this being released due to bad health he would die in 1995 from complications from his exposure brookanov who had helped cover up the partial meltdown at unit number one in 1982 was also given 10 years but still lives to this day and also served a shorter term in his sentence even though i suppose the perpetrators were punished the culture of the ussr nuclear industry meant that rules were regularly and blatantly broken and overlooked especially when it came to important things like the orm which ultimately put the reactor in such a deadly state this was all highlighted in the 1992 in sag seven reports which also said in its summary the plant fell well short of the safety standards in effect when it was designed and even incorporated unsafe features compounded by inadequate and effective information between both operators and between operators and designers there was an inadequate understanding by operators of the safety aspects of their plant also affected by insufficient respect on the parts of the operators for the formal requirements of operational and test procedures the industry in ussr had an insufficiently effective regulatory regime in place to counter pressures for production the pressures from central government and lack of awareness of the design risks of the reactor meant that management acted dangerously in the false pretense that the rbmk was indestructible pretty much the entire management structure was throwing around a grenade that they didn't know had the pin pulled out of meaning disaster was only a matter of time now i'll be following up this video with another video at some point about the wider impact of the disaster on local and wider population as well as digging deeper into liquidators and their heroic work thanks for watching i hope you enjoyed the video this video is a plain difficult production all videos on the channel are created commons attribution share alike licensed plain difficult videos are produced by me john in a sunny south eastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos nods and sods as well as hit some switcher videos i've got patreon and youtube membership as well so if you fancy checking them out feel free to and all that's left to say is thank you for watching structural failures can usually be categorized into two groups the first being financial for example cutting corners during construction improper maintenance or just outright corruption but the second category is more psychological and that is constructing whilst ignoring any potential warnings large scale projects are always susceptible to a type of thinking resulting in construction completion with a safety compromise structure this is known as completion bias and can create a tunnel vision effect where warning signs are missed due to so much time and money being invested in a project a great example of this is in the private pilot realm where the embarrassment or need to reach a destination results in continuing to fly in poor or outright dangerous weather conditions which has sadly many a time resulted in disaster the effect has been seen several times in the dam construction industry which have resulted in disasters for example like the villon dam where geological warnings were missed resulting in a catastrophic overtopping and flood today we're looking at the titan dam failure which will result in eleven dead thirteen thousand cattle killed a hundred million dollars in construction costs and over three hundred million dollars in claims for remediation our story starts all the way back into the early 1960s and the perceived need for a new dam to be situated three miles north of new dale idaho on the titan river the area had experienced a severe drought in 1961 followed by severe flooding in 1962 and the bureau of reclamation set about to try and tackle this whilst also bringing other benefits of a dam to the region the titan basin project as it was to be known would include a new earth and dam to impound a new reservoir for the generation of electricity flood control irrigation of farmland and recreational activities the reservoir will extend 17 miles upstream holding back around 288 000 acre feet of water with a surface area of 2100 acres the area selected for the new dam was in a canyon that had been carved out by the titan river in the snake river plain the plain was almost entirely underlain by 1.9 million year old balsalt and rhyolite both of which aren't the best foundation material for a new dam due to their high permeability regardless the bureau of reclamation continued on with the project around a hundred core drills were bored at a future dam site between 1961 and 1970 and highlighted the need for further investigation of the site some leakage tests were undertaken on the planned right hand abutment side and showed no water leak from the abutment however the levels of water in the surrounding holes did rise this led to tv camera investigation which showed many cracks and joints of random orientation but a left abutment investigations into its suitability involved grouting into the rock to see the effectiveness of filling the cracks in the foundations initially all seemed acceptable and the information was passed along to the designers of the dam in 1963 the project was authorized and by 1971 after initial planning an environmental impact statement was produced the project would have many objections after this initial statement and this was for many reasons brought by locals and environmental conservationists this was due to the ecological impact on the local areas wildlife as with any feeling of a reservoir a large area now finds itself underwater on the 27th of september 1971 several environmental and conservation groups brought a lawsuit in idaho district court to stop the construction amongst the environmental complaints were also a strong economical one stating that the return on investment from the dam wouldn't be all that great not only that but questions were raised over the geological suitability of the area for a dam the lawsuit and concerns delayed the tender for the construction contract at least for a while but eventually morrison nudson co of boys assisted by pete kewitt and sons of oma har nebraska won the bid in december 1971 with initial construction works to begin in early 1972 the suit would be dismissed in 1974 just two years before the disaster but that would only be the start of the warning signs for the suitability of the project but first let's have a look at the design of the teaton dam the plans for the dam were made under the direction of the office of design and construction at the u.s. bureau of reclamation at their denver federal center it was to be an earthen type field dam using soil dug from the reservoir location the designers were aware of the surveys which highlighted seepage issues and planned for excavation to groutable rock slush grouting under the core outside the key trenches and downstream holes or tunnels a continuous grout curtain along the entire foundation was to be used extending about a thousand feet into the right abutment at about 500 feet into the left abutment the dam centerline was straight for 2000 feet of its length and curved upstream on the right abutment for the last 700 feet also on the right abutment was the spillway which had a gated chute structure with an auxiliary inlet and outlet for each abutment a trench had to be cut into the rock sides of the canyon there was a river outlet underneath the left abutment which took water from the reservoir bed for use at the pumping and power station the dam's embankment consisted of five zones zone one was the center core and was the largest part which took the longest to construct the center of the dam was a mixture of clay silt sand gravel and cobbles tightly compacted by tamping rollers to form a core this was fought by the bureau of reclamation engineers to be impervious to water next came zone two which was placed over the core and composed of sandy gravel compacted to an average relative density greater than 70 percent zone two was extended downstream across the floodplain and on the abutments underlying zone three zone three consisted of miscellaneous fill zone four was similar in construction to zone two and served as the upstream cofferdam zone five was rock fill in the outer parts of the embankment all zones created an overall height of 305 feet above the riverbed right let's get onto the construction which began in february 1972 initially the spillway and key trenches were excavated initially river flow was directed through the middle of the canyon so that excavation could proceed on both abutments after this was completed the river was again diverted into a channel along the right abutment to allow the cutoff trench to the left of the channel to be dug warning signs were found during these initial works as large open fissures were discovered during excavation of the key trench near the right end of the dam several voids were found and had to be filled in with portland cement with some of the fissures actually being caves which resulted in more work than originally thought at this point the structural suitability of the foundation should have come into question but with so much time and money poured into the project so far it just had to be completed the entire embankment foundation was stripped of all unsuitable material including boulders loose rock and topsoil in january 1973 a us geological survey team inspected the site and sent a memo to the bureau of reclamation saying safety of the teaton dam project is of immediate concern and pressures from the filled reservoir and loading could trigger movement that would endanger the dam the bureau's head of design and construction how g alpha rebutted these concerns asserting that the teaton site lay in a favorable area from a seismic standpoint which directly contradicted the us geological survey during the 1973 construction season the cutoff trench in the river channel was completed as was the grouting in the lower part of the foundation the river was diverted once again through the outlet works on the 8th of june 1973 this diversion enabled construction of the cutoff trench on the right side and the placement of the embankment on the trench towards the end of the year the first of the zone one material was placed in the foundation trench on the 3rd of october 1975 the river was diverted again when the auxiliary outlet was put into operation to enable placement of second stage concrete in the intake and gate chamber of the river outlet and to install outlet gates pipe penstock manifold and metal work and equipment the zone one area was completed in 1975 allowing the remaining material for the dam's embankment to be placed on top throughout the rest of the year were construction completed in november 1975 with this newly constructed dam the next thing was to fill the reservoir behind it the us bureau of reclamation set out to monitor the performance of the foundations and structure during the filling process this was to ensure that the dam was safe for operation part of his monitoring was checking the face of the dam for seepage as well as checking the waterboard downstream for any abnormal rises the plan was to have the reservoir productive for irrigation in 1976 and open to the public by 1977 with the initial filling rate to begin at one foot per day the reservoir bed was at around five thousand and fifty feet in elevation that as the water level rose the reservoir surface elevation would also rise by march the reservoir water surface was at an elevation of five thousand one hundred and sixty seven feet the auxiliary outlet was releasing water at 295 cubic feet per second the director of design received a memorandum from the construction engineer that would be worrying wells that have been dug for water table observation had shown a significant rise but it was felt that it wasn't anything to worry about as the dam had been inspected and no leaks were found on the 23rd of march the allowable filling rate was increased from one to two feet per day because the river outlet work was still incomplete and the runoff from the Teton river was abnormally high the reason for the high runoff was due to increase snowfall in January that had melted increasing the flow rate the reservoir was allowed to rise in height as the spillway was thought to have been able to handle any flooding from the eleventh of may until june the fifth the average rate of rise was at three feet per day with a maximum of four point three feet on the 18th of may the redwire level continued to rise up to the maximum depth of 240 feet on the third of june 1976 seepage was discovered in small springs in the right abutment on the downstream toe of the dam they were flowing water at approximately 40 to 60 us gallons per minute what was strange was that the flow of liquid was clear and not brown in color which was more common of erosion on the fourth more leaks were found on the right abutment again flowing clear water at approximately 20 us gallons per minute more seepage was discovered on the fifth of june around 730 in the morning but this time the water color was that dreaded brownish but due to the clear water before the engineers did not believe there was a problem a wet spot on the downstream face began eroding its way into the abutment on the right side of the dam two bulldozers were sent down to try and fill the leak which is this really small dot on this photo at around 10 14 the morning an emergency call to prepare for flooding was made to the madison and fremont county sheriff's office at around 11 a.m one the bulldozers started sliding into the opening the other bulldozer attempted to pull it out between 11 and 11 30 a.m the project office called the sheriffs again and told them to evacuate the region immediately something that definitely can't be a good thing to see appeared at around 11 30 a.m and that was an increasingly big whirlpool in the reservoir near the right hand side of the dam the two bulldozers on the abutment started to sink into the opening and both operators abandoned their machines in the meantime two more bulldozers attempted to block the whirlpool by dumping material but this yielded no results the flow for the opening continued to increase until 11 55 a.m when the dam began to breach at the crest just two minutes later total failure had begun as the reservoir waters broke through the teat and dam and rolled downstream the water carried away about four million cubic yards of the embankment bearing the power and pumping plant beneath over two million cubic feet per second of water emptied through the breach into the last six miles of the teat and canyon from there the flood spread out into the snake river plain a 15 feet high wall of water sped along at around 10 to 15 miles an hour hitting and decimating the towns of wilford and sugar city the water then swept through a log mill which added debris to the flow resulting in the city of rexburg being battered by 8 p.m the reservoir had completely emptied leaving around two-thirds of the main dam structure remaining on the 6th of june president gerald ford declared bingham bonville fremont madison and jefferson counties a federal disaster area 11 people were dead with five of which being wilford residents luckily a higher death toll was averted by the evacuation warning but regardless the property damage was immense which leaves us a question how did this multimillion dollar brand new dam fail immediately after the failure reclamation commissioner gilbert g stan an assistant secretary of the interior arrived in idaho to inspect the site two investigation panels were set up but like most dam failures eyewitness testimony had to be relied upon due to most of the evidence being washed away during the breach however excavations of the remaining parts of the dam did yield some hints at the failure mode a house of representative subcommittee was also set up headed by leo ryan the same man that would tragically be killed in gianna in 1978 by jim jones followers the hearing and investigations highlighted the dubious selection of the dam site due to the permeability and porousness of the rock in the valley the likely cause of failure as stated in the independent panel to review the cause of the teaton dam failure theorized that piping was caused by erosion of the dam via the porous nature and open joints of the rock at the dam site stating it was recognized by the usbr early in design and confirmed by the panel's investigation that zone one material placed in the key trench and against the abutments was highly erodible as a reservoir level rose the hydrostatic pressures in the upstream jointed rock increased to a point that would have been sufficient to cause hydraulic fracturing resulting in main structure erosion congressman ryan was concerned with a thing he called momentum theory which is similar to completion bias which was endemic in the government organization where the bureau of reclamation had never stopped a project after construction had begun this was especially true for teaton where the us geological survey had highlighted key faults with the site selection in 1973 but a project already in construction went ahead regardless the speed at which the reservoir was filled became a point of criticism as if the filling had been slower than the near three to four feet per day at its peak then the project employees could have highlighted and fixed any issues but the bureau eager to complete the project allowed for a higher fill rate even though not all the outlets were finished the grout curtain came under criticism as well saying that it was inadequate for its purpose as well as the use of a narrow foundation main trench after excavation of the remains of the dam more wet spots were discovered showing that defences built into the design to prevent water penetration were inadequate all the investigations came across similar conclusions it is best summed up in the independent panel investigation summary stating the fundamental cause of the failure may be regarded as a combination of geological factors and design decisions that taken together permitted the failure to develop finally saying in final summary under difficult conditions that called for the best judgment and experience of engineering profession an unfortunate choice of design measures together with less than conventional precautions was taken to ensure the adequate functioning of the teaton dam and these conditions ultimately led to its failure if the bureau had stepped back not focused on the end point and taken in the whole picture during construction then maybe they would have seen the dangerous situation they were creating but unfortunately they focused on the destination and not the journey the financial ramifications of the disaster would run into billions and unsurprisingly a number of suits would be brought against the bureau of reclamation before responsibility for the teaton dam's failure was decided a week after the disaster president Gerald Ford requested $200 million for initial payments for damages the cleanup works began almost immediately but the long-term effects were disastrous the ecosystem downstream from the dam was wiped out affecting trout populations the bureau of reclamation set up offices in rexburg idaho falls and blackfoot for the purpose of people to make financial claims from the government by the end of the process in 1987 over 7500 claims were made totaling $322 million the dam was never rebuilt and remained a ruin which became a testament to the pitfalls of completion at all costs this video is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me john in a kind of sunny south eastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching the bond between mother and child can be unbreakable the complex relationship is difficult to quantify as when does it begin in the womb postpartum regardless the relationship in nature is vital for the life expectancy of the infant as without a caregiver food and security are not secured but what if we could boil the mother child relationship down to its basic components perceive security comfort and nourishment that is what today's topic sought out to explore the nature of love although the experiments did not test the human mother child bond it did try out on one of our closest cousins i must warn you of the subject matter in this video although a fascinating dive into the psychology of motherhood it does involve despair sadness and arguably horrific results for the test animals taking this into account i'm going to rate it here four on my ethical scale the reference one is completely fine and 10 being just outright evil i've given this number due to the experiment not being as detrimental to the monkey's health as say the head trance plants were although in some cases severe psychological trauma was inflicted on the test subjects of course this video is about the controversial monkey mother studies by harry harlow welcome to the dark side of science in 1981 the scientific community mourned the passing of a psychologist whose studies became a fascinating and sometimes controversial dive into animal psychology before we get into the experiments in the late 1950s our story starts in fairfield iowa in 1905 with the birth of harry israel the third or four brothers in 1924 he began to study psychology at stanford university being taught by a couple of notable scientists one of whom would shape the young psychologist's future career during his university career israel was under the watchful eye of louis terman developer of the stanford binna iq test he received his phd in 1930 and under the advice of his mentor harry changed his last name from israel to harlow harlow started working at the university of wisconsin madison he had asked for the laboratory space but this was denied this was due to the university's animal testing laboratory being torn down initially wanting to study on rats harlow then gained access to henry villas zoo where he discovered the primates there would be preferable to rodents for his studies in 1944 he left the university and worked various different jobs in the scientific community including being the president of division of experimental psychology at the american psychological association and head of division of anthropology and psychology at the national research council he returned to madison university in 1956 and took the role of director of the primate lab he was offered an abandoned building on the campus for his studies this old rundown structure would be the location of his controversial studies into monkeys during his work using monkeys he devised several problem solving and intelligence tests proving that by mere curiosity alone the subjects would want to solve the puzzle his studies would develop into different intelligence tests for a whole range of age groups but he had a problem and that was a reliable source of infant and developing monkeys harlow set up a rhesus macaque monkey breeding colony to gain access to developing primates for his experiments by doing so his experiments would take a different course part of his program employed rearing the monkeys in a nursery away from their mothers which is a controversial method but harlow had found it hard to do intelligence tests on infant monkeys with their mother around he noticed a staggering difference between his reared infants compared to their mother reared peers most notably their behaviour as they were reclusive had little in the form of social skills and took comfort from holding onto their cloth diaper cage linings they also found that the subjects would experience severe stress and anxiety when the diapers were removed from their cages during routine cleaning harlow and his students were fulfilling the infant's physical needs but the team soon noticed the psychological deficiencies from nursery rearing he also noticed that the infants that were mother reared but socially isolated from other monkeys also showed strange behaviour either being introverted or aggressive when introduced to others were the infants taking comfort from their cloth diaper cage linings harlow thought that this was due to the lack of a maternal figure and would become the basis of a new experiment the concept of the monkey mother would begin to form in 1957 when harlow covered a wire frame in a rough shape of a monkey with a diaper cloth the new test apparatus was thought to be the minimum requirement for a recess monkey in terms of contact comfort now this leads us on to the monkey mother experiment and harlow's famous paper the nature of love harlow set out to study the development of affectional responses of neonatal and infant monkeys to an artificial inanimate mother the study would create two types of monkey mother surrogates boiled down to the basic components that a monkey infant would want warmth and nourishment in the form of radiant heat from a light bulb and a single teat for milk dispensing the first mother was a wire frame formed in a way to be adequate to provide postural support and nursing capability the second was made from a wooden block with a sponge rubber covering which was then itself wrapped in a tan coloured terry cough both were capable of providing milk and were warm the only difference was the comfort element of the mother's one being able to be cuddled up to and the other not both were designed with maintenance efficiency in mind thus only had one teat per monkey and were able to have their warming light bulb replaced easily with little interaction between the test subjects and the technicians for the initial experiment both surrogates were placed inside cages of eight newborn monkeys four had the cloth mother lactate and the wire one not and the other four had the opposite so the wire mother could lactate and the cloth one could not initially during the first few days of the newborn's life they were hand reared until they're able to explore the surrogates for milk after which for a few more days supplementary hand feeding was done until the newborn could fully feed off the surrogate for the first 14 days of life the cage floor was warmed and had a cloth lining on the 15th day the comfort flooring was removed and the proper experiment began with the amount of time on each mother recorded the monkeys were free to go to either mother if they so chose with the lactating cloth mother unsurprisingly spent most of the time on their surrogate using her as a source of affection and comfort what was interesting though was the group that had the lactating wire mother as the monkeys got older they spent less and less time on their feeding surrogate and instead went to the cloth mother for comfort during the experiment he was seen in the long term that the monkeys with the wire mother that could feed would increasingly spend more time up to 18 hours a day on their cloth surrogate spending on average under one hour per day on the one that could give them food this meant that the infant monkeys were preparing the contact comfort and perceived affection in all cases regardless of which one provided the milk the monkey would prefer the cloth mother for cuddling proving that at least in the study that the mother baby bond wasn't just created from nursing but instead the capability for love and that it overwhelmed any other variable another eight monkeys were used as controls for the experiment with each not having a choice of wire or cloth instead for having a lactating wire mother and the other four having a lactating cloth mother only both control groups were roughly the same weight by the end of the study meaning the wire monkey was said by harlow himself biologically adequate but psychologically inept but there is one difference and that was in their poo you see the control wire only mother group had softer stools hinting at psychosomatic issues harlow now sought out to test the bond between infants and surrogate by introducing the element of fear in all cases of dual surrogate the subjects preferred to go to the cloth mother when something scary happened what was interesting was after a little bit of time to cling on to their cloth mother the infants actually became confident enough to confront the scary object this wouldn't happen if they were clinging to the wire surrogate next came the open field test where each monkey was placed inside a six foot by six foot room with various items placed within it initially the room had various toys and interesting objects but no mother when confronted by the strange and scary environments the infant would curl up in a ball in a notable amount of distress when a wire mother was introduced no change was seen but when the cloth mother regardless if it had really infant was introduced the monkey would go to her for comfort and after a while would then have the confidence to explore even if an obstacle was placed between the monkey and the cloth mother the infant would make a beeline for her a control group that had not had any contact with a cloth mother before was used in the open field test and the monkeys would be paralyzed with fear regardless of the presence of a surrogate but would eventually get some comfort from the cloth mother after several sessions in the test room the test developed further by placing the cloth mother behind a glass wall with a scary object in between again like before the infant that being raised with the surrogates would run to her Harlow then went to test how long the bond could last between surrogate and infant some of the monkeys were removed from their cloth mother after six months and placed in a cage of their own after another six months had passed the monkeys were around their first birthday they were placed inside the original dual surrogate cage and the infant would go straight to the cloth mother the same results were also shown in the open field test when a monkey would still run to its cloth mother for comfort in a scary and new environment this meant that the test subjects remembered the comfort that they got from their mother and reverted back to their pre-isolated state to further test the bond difference between control and surrogate monkey groups another machine was devised called the flight box the test rig had a scary object placed in one end behind a removable wall the monkey would be placed in the middle of the box with two passages in front of it one to a cloth mother and another to a hiding spot out of view from the fear stimulus the results were rather predictable when the scary object was revealed the surrogate raised subjects would seek comfort from their cloth mother whereas the control monkeys would run and hide down the other passage now the monkey mother experiments helped to prove the link between comfort and security and infants and how it was preferred over nourishment which feels today like an obvious statement but if it wasn't for the experiments like this then we would still have a slightly view towards child rearing the studies did have a dark side and that was the socially and emotionally deprived test subjects which by modern standards feels wrong just looking at the fear in the monkey's faces makes me sad as a parent I can see the sadness similar to a human child and it makes me want to go pick up the monkeys give them a cuddle and tell them everything is going to be okay the studies came under severe criticism at the time and in the eyes of history have not come off well one major mistake of the experiments was that the link in behavior between human babies and rhesus babies was a bit tenuous this was because although human infants grab to their primary caregivers they do not rely on contact comfort as much as a monkey does you see this in young children that are happy to play on their own and be pushed around in prams whereas monkey babies are transported by clinging on to their mothers relying more heavily on contact for survival there are many more variables which are not addressed in Harlow's work especially when it comes to human child caregiver bonds for example financial societal and cultural variables which some of these elements are not factors in the society of the rhesus monkey the social and maternal deprivation of the test subjects cause panic and anxiety disorders which further added to the suffering of the heavily social based rhesus monkeys when introduced to other monkeys that had a more maternal upbringing were socially stunted and showed signs of severe distress when in contact with their peers Harlow's studies and others like it are cited as being a fuel in part of the animal rights movement in the United States Harlow went on to continue to use rhesus monkeys in his studies which would go down a much darker path in the exploration of loneliness isolation and depression including a study apparatus called the pit of despair which is most probably going to be a subject for a future video where would you rate this experiment on my new epic scale let me know in the comments below this video is a plain difficult production all videos on the channel are creative commons attribution share alike licensed my difficult videos are produced by me john in a semi sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching criticality accidents are a technician's worst nightmare although a rare occurrence they can and do happen and can result in severe radiological exposure and an expensive cleanup process an event would unfold in the russian federation in 1997 and would have some similarities to two of the most infamous criticality accidents those being the deaths linked to the demon core although not identical the accidental prompt criticality of some fissile material due to accidental dropping of a reflector does sound familiar to louis slotton's exposure the accident would result in a dead very experienced technician and a six and a half day excursion i'm going to rate this event here four on my painted plain difficult disaster scale this is due to the event being relatively localized and didn't result in significant contamination sarov is a city in nishne Novgorod oblast russia originally founded in 1691 but our story starts quite a while after that in 1946 the town became a closed city and it was removed from all unclassified maps the reason was well but it found itself the center of the soviet nuclear weapons industry the all union scientific research institute of experimental physics was set up in the town which was a nuclear weapons design facility the institute over the years had set up testing grounds and hundreds of experimental facilities leading it to become the country's largest research and development organization as a quick side note the city became twinned with lost animos in the early 90s post collapse of the ussr the nuclear center was still the heartbeat to the russian nuclear industry conducting experimental studies in the fields of physics radiobiology and the health effects of radiation set over 12 facilities one of the purpose built facilities was the critical assembly which was designed to be an experimental tool to study fission reactions relevant for design and development of power research and impulse reactors the assembly was placed on a cart on tracks inside a room surrounded by concrete walls with a separate control room there were also other rooms for storage and workshops and each room had air samplers and detectors for measuring gamma radiation the critical assembly was essentially a piece of fissile material surrounded by two reflectors although the actual implementation was a little more complicated the assembly had the ability to move the fissile material inside a half sphere reflector up and down through the use of hydraulic pressure towards or further away from a fixed upper half sphere reflector for the construction of the assembly our calculations are used to ensure the fissile material remains subcritical the construction process involves excessive layering of various materials including copper steel and uranium which are prepared in the form of sets of machined hemispherical shells of standard sizes which the technician can assemble into various configurations the process was broken into two parts first constructing the lower half of the critical assembly then the second top half the lower half of the research assembly is constructed on a table that can move vertically up and down using hydraulics but the first part the table had to be in the up position during construction of the assembly but the second part the lower assembly is lowered and the upper part is placed on a stand consisting of a ring where it can be positioned horizontally over the lower part of the system once the whole assembly is constructed the operator is then meant to go to the control room to undertake the experiment also I should say that during the construction process it's meant to be a two-person job the operator and a supervisor who should be double checking all of the work during the experiments the assembly was essentially a small fast reactor that can regulate itself in a rather clever way if the mathematics are correct then as the assembly heats up the materials expand reducing the effect of the reflectors and as it cools down the components return to their previous position the behavior is seen as sharp fluctuations of the measured neutron flux which stabilizes after several cycles after which the critical assembly operates at a constant level of neutron yield sensors placed inside the assembly room tell the operators the state of the materials which allows them to move up and down the lowest sphere to change the power levels if the assembly went out of control it would melt thus ending the chain reaction and was an important safety feature all experiments using the assembly were strictly controlled by a regulatory and technical framework set out by the russian federation ministry for atomic energy the procedures precisely outlined the management requirements for work with critical assemblies they require that this type of work be conducted only by a group of trained technicians with each person being responsible for strictly defined actions within a sequence of operations which are closely supervised obviously this is important as a mistake can result in a criticality event which you know is not great but we can probably predict what is going to happen next roll on the morning of the 17th of june 1997 a 41 year old male named alexander zhakarov set to recreate a 1972 experiment using uranium with a copper reflector assembly a technician was a very experienced worker with several hundred experiments under his belt he was familiar with the process for the particular assembly but contrary to the rules he was working alone in the hall zhakarov had also broken another rule and that was by not properly filling out the appropriate paperwork for the experiment he had taken the dimensions for all of the components from the original 1972 log book but he had mistakenly written down the wrong outside diameter instead of 205 millimeters he noted 265 millimeters at 10 50 a.m whilst placing the upper reflector on its stand above the fissile material it slipped from the technician's rubber-gloved hand and fell onto the lower part of the assembly this sent the subcritical assembly prompt critical and a blue flash of light and a heat wave was experienced the lower part of the assembly was ejected downwards into the bottom of the stand knowing his mistake zhakarov fled the room and reported to his superiors explaining the situation he claimed to have received more than a fatal dose initially he was conscious but within minutes his exposure began to take its effect the radiation protection personnel performed an initial radiological survey of the technician this detected the neutron induced gamma radiation emitted by radionucliides in his body it was estimated that he had received a whole body dose of 10 gray for comparison between four and six gray whole body dose has been lethal before zhakarov was sent to hospital for treatment arriving at sarov occupational medical service at 11 45 in the morning on the 17th of june by this time he was experiencing nausea and he began to vomit increasing in frequency over the following two hours the sickness was lessened by 2 p.m. by antibiotic drugs the situation was looking pretty dire as his condition deteriorated it was decided in the evening that he be transferred for specialist care in moscow he was admitted to the clinical department of the institute of biophysics in the ministry of health at 9 p.m. he was fully conscious but his fatigue and headache were persistent his hands showed signs of severe exposure they would become severely swollen during the first night between the 17th and the 18th of june on the morning of the 18th of june the patient's general state was evaluated as critical and getting worse by the hour his hand injuries continued to worsen with the spreading of the swelling over more areas of the forearms on the 19th of june the condition of zhakarov was dire by 2 p.m x-rays showed fluid on the lungs and his arms were deteriorating rapidly later on in the day the decision to amputate both arms was taken and the surgery was performed around 4 p.m. initially his condition was stable but sadly not for long at 2 45 in the morning of the 20th of june 1997 his blood pressure dropped dramatically and at 3 20 in the morning around 66 hours after exposure the patient died but what happened to the critical assembly after zhakarov left the room and was taken to hospital as the technician passed away in the early hours of the 20th of june the chain reaction would still be ongoing back to 10 50 in the morning on the 17th of june the specialists arriving at the accident facility had to determine the status of the critical assembly and the possible consequences of the accident at 11 a.m evacuation of all staff from the building where the accident had occurred and the radiation survey outside the building was carried out by the early afternoon it was confirmed that there was no airborne or surface contamination but the assembly was still emitting significant neutron and gamma radiation which would preclude anyone from entering the room all but the dosimeter furthest away from the experiment showed readings off the scale another meter was entered into the room and showed the neutron flux was stable hinting at the chain reaction being self-regulating obviously the chain reaction had to be stopped and this necessitated altering the assembly remotely the first step taken was to remove containers of nuclear materials which had not been used in the construction of the assembly this was conducted by using a robot once complete the same robot was used to alter the assembly at 12 45 in the morning of the 24th of june 1997 when a vacuum gripper was used to remove most of the assembly from the sand leaving only the outermost lower copper hemicell in place the remainder of the assembly was disassembled bringing an end to the incident due to the excursion the radiation monitors in other rooms of the facility showed normal levels but the technicians personal dosimeter read a neutron exposure of 45 gray and a gamma dose of 3.5 gray it was thought that the uranium had reached temperatures of up to 865 degree centigrade during the excursion because the accident was solely down to zhakarov and his infringement of the rules set out by the facility although his death is a tragic accident some comfort can be taken of that no one else received elevated radiation doses although the IAA found the rules of the facility to be adequate they still did not prevent the accident after the accident experiments with the test rig were stopped to implement safety upgrades to the research operations this is a plain difficult production all videos on the channel are creative commons attribution share alike licensed playing difficult videos are produced by me john in a not so sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well so you can check them out if you fancy supporting the channel financially and always have to say yes thank you for watching phobias are a fascinating part of the psyche some are completely understandable and possibly even evolutionary as being scared of dangerous things and creatures is pretty beneficial for survival but a question has eluded psychologists how are phobias present in some people but not others and can you condition a fear in a human test subject this question would lead psychologist john b watson and his assistant graduate student rozzolene reyna down a very ethically questionable path not only was experimenting on a human controversial but the test subject would be a nine month old baby today we're looking at the controversial heartbreaking and morally questionable baby albert experiments welcome to the dark side of science nothing about the statement experimenting on a nine month old baby sounds good and the idea to deliberately scare an infant is very off-putting the experiment is even more controversial than the monkey mother studies as the long-term effects could be scarring for an otherwise healthy human child as such i'm going to rate the experiment here eight on my ethical scale as a subject had no say in becoming part of the study and to the alleged sourcing of the child was not shall we say in the most praiseworthy way but before we get to baby albert we need a little background to the person behind the experiment john b watson john broadus watson was born in travellers rest south carolina on the ninth of january 1878 he was brought up in a strict christian family but things would change in a teenager's home life when his alcoholic father left the family this would cause john to become apathetic towards religion the family later moved to greenville south carolina where watson would get a chance to meet people of different backgrounds igniting his interest into psychology his secondary education was marred with run-ins with the law for fighting and bizarrely discharging a firearm within city limits however he was still able to gain a place at greenville's firman university at the age of 16 his time at university was difficult having to work several jobs he didn't excel and did not create many social bonds which left people to think of him as lazy and antisocial but he persisted and at the age of 21 gained a master's degree he managed to get into chicago university a couple of years later and finally his career started to take a more positive turn studying under some notable professors including jong dui and james roland angel watson began to develop an interest in behavioralism during his time at chicago he read up on the work of ivan pavlov known for his classic conditioning a discipline which would directly influence watson's later experiments as a side note this is the same pavlov with the dribbling dog i should say that during this time watson had got married and was the father of two children but his marriage would break down but this will come a bit later on in our story in 1902 watson gained his phd whilst working as a research professor at the university of chicago in 1908 watson accepted a faculty position at john hopkins university being promoted to chair of the psychology department not long after starting he continued to study behavioralism releasing a paper in 1913 named psychology as the behaviorists views it a manifesto of sorts laying out the goals of the new discipline behaviorism as watson saw it sought to understand behavior by only measuring observable behaviors and events and that these actions were influenced from external stimuli as a consequence of that individual's history and learned behavior from reinforcement punishment this new form of psychological study wasn't initially accepted by the wider scientific community but gradually the new discipline would make inroads to be a recognized field the discipline would be expanded upon by scientists like bf skinner aka the guy who made a pigeon guided bomb which i made a video about a long time ago check it out if you want to see a even worse produced plain difficult video in 1915 watson served as the president of the american psychological association watson would continue to produce papers expanding on his views into behaviorism which would reject the study of consciousness with his important later career 1924 book behavioralism but before that we need to look at a couple of very turbulent years for watson which brought about the baby albert experiment in 1919 watson released a paper called a schematic outline of the emotions during this study he observed a number of infants which revealed three fundamental motions fear rage and love each caused by a set of conditions watson used various animals to observe the reaction from the test subjects in most cases especially when introduced to dogs and cats the infant showed a neutral or an inquisitive reaction but when introduced to a pigeon flapping its wings most subjects showed surprise or even fear of the motion and sound to induce fear some of the test subjects were placed in a dark room or in a room on their own needless to say the children became distressed now these tests are pretty mild and generally yielded predictable results but what if you can get an infant to fear something that had initially yielded a neutral response for example one of the cuddly animals from his 1919 study this would be done by introducing a neutral stimulus like a rabbit with a scary stimulus for example from a loud banging sound they tried to answer the following questions that if a fear stimulus could be transferred to other animals or other inanimate objects once a fear of being conditioned to in the test subject they also went to find out for how long right this is where the study in my opinion crosses the line as the sourcing of the test subject and finding a parent willing to allow their child to be given a phobia would be understandably difficult baby albert was a child of a wet nurse at the harriet lane home a pediatric facility on the john hopkins campus now it's not 100 known how albert was found clearly a major contributory factor was the convenience as harriet lane was adjacent to the fifth clinic where watson's infant laboratory was housed there are three possible ways watson got hold of albert that have been considered the first is for a paid study the second is by using his connections at the hospital to coerce and allow access to the infant and the final is from doing the experiment without the mother's knowledge but we will never know a hundred percent how albert was found by watson and we don't even know if that is his real name what we do know is that he was selected due to being healthy unemotional child who rarely cried the experiment wasn't just conducted by watson alone but also one of his graduate students rosaline reyna i should say that his relationship with her had caused issues with his breaking down marriage by late 1919 at the start of 1920 and at eight months and 26 days of age baby albert was entered into the study albert was observed reacting to a number of live animals for example a rat a dog a rabbit and a monkey and various inanimate objects including human masks cotton and a burning newspaper during the initial phase albert showed no elevated signs of distress or major reaction to the stimuli what watson and rosaline did see was elevated distress when a metal bar was hit with a hammer which created a large amount of noise sending little albert into a burst of tears two months would go by after albert's baseline observations before the experimental conditioning would begin watson and reyna attempted to condition him to fear one of the items that had previously garnered a neutral response a white rat was chosen to be an item to condition albert's fear response this was done by presenting the animal to the infant and every time he touched it the metal pole was hit with the hammer creating the scary noise it wouldn't take long for albert to start to fear the cuddly animal after seven pairings of the rat and the noise in two sessions one week apart albert reacted with crying when the rat was presented subsequently with no loud noise although he didn't seem as distressed when he was allowed to suck his thumb which hints at a phobia not actually being created a couple of weeks after the conditioning albert started to fear other similar items that shared similar characteristics with the rat the generalized fear manifested whenever the family dog a fur coat some cotton wool and even a father christmas mask was presented to the infant a couple of weeks after that albert's fear of the rat had died down including the response to the other similar items this prompted watson to recondition the infant by presenting the rat again with the loud noise each reconditioning would only take a few rounds of the scary noises but what are the questions set out by the pair before the experiment how long does the condition last 31 days after no exposure to the test items albert was shown a rat a coat and santa mask he again showed a fear response not long after the final experiment albert's mother withdrew her child from the study and left the hospital for good leaving little trace of what happened to the test subject this had two downsides the first was that albert was unable to be reconditioned to not fear the rat and the linked fear producing things and the other issue was that the study was incomplete right well taking into account that the experiment happened over 100 years ago we do have to look at it in the context of the time when experimental psychology was in its infant hood and the study was even one of the first to be filmed at a great cost to the university by today's standards the experiment was morally ethically and even scientifically on shaky ground the first two reasons are pretty obvious as well experimenting on children is just wrong at least in my eyes but the scientific failures are very important to consider the study did not have a control subject involving only one infant which makes the data hard to properly interpret as one result does not make a conclusion it's almost impossible to know longer-term effects on baby albert as we may never know if the phobias if any created during the experiment were long-lasting we will never know for sure what happened to albert or even if it was his real identity researchers into the experiment have a couple of potential identities with one dying at the age of six and another living until 2007 but we will never know for sure some doubts present as to whether or not the conditioned fear response was actually a phobia this was due to a reduced response when the infant was allowed to suck his thumb which almost made him be able to ignore the loud sound the experiment was responsible in part for destroying Watson's working career but not how you might think what came out later in 1920 was that the psychologist was having an affair with his assistant Rosalind Rayner the scandal would result in Watson's dismissal from his job at john hopkins university the affair became front page news during the divorce proceedings in the Baltimore newspapers destroying the psychologist's reputation and with it his university career not that that was the complete end for him as he released his behaviorism book in 1924 and also psychological care of infant and child in 1928 he would have another two children and would work for an advertising company from late 1920 he would raise both children to his and Rosalind's behaviorist principles and sadly both sons would attempt suicide with one of them being successful in 1954 Rayner died on the 18th of June 1935 in Norfolk Hospital in Connecticut she had unexpectedly contracted dysentery from eating tainted fruit Watson would never remarry and pass away himself in 1958 at the age of 80 this is a playful production all videos on the channel are creative commons attribution share alike licensed playing difficult videos are produced by me john in a kind of sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership if you fancy supporting the channel financially and always have to say yes thank you for watching damn failures are catastrophic events the sheer magnitude of the destruction they reap is unimaginable one such disaster in 1963 caught live on tv would show the world the potential havoc that can be inflicted on a community a failure to recognize the risks of poor site selection would show that the los angeles department of water and power had not learned the lessons from the st francis dam nearly 30 years earlier the event did however show the benefits of regular inspections as even though failure would destroy hundreds of homes and run into the costs of millions the death toll was a relatively modest five it was saying that the Baldwin Hills dam failure was assured when the project was green lit but heroic actions on the day limited the potential for tragedy as such i'm going to rate it here four on my disaster scale but here on the legacy scale as it was one of the first dam failures caught on live tv welcome to a brief history of the Baldwin Hills dam and reservoir failure our story starts just before the second world war and the plan to build a reservoir to supply the south la neighborhood of Baldwin Hills with safe and reliable drinking water la throughout its life has been plagued by droughts which was the original reason for the la aqueduct sys