Talk:Fukushima nuclear accident/Archive 1

deaths
so far, in F dai ichi, one dead crane operator is reported http://www.spiegel.de/international/         --92.227.142.21 (talk) 23:20, 12 March 2011 (UTC)
 * true, thanks for the information. ...and so says the article as well now! L.tak (talk) 23:22, 12 March 2011 (UTC)
 * also reported in the English TEPCO press releases . IIRC cause of death is not given there. --Zippy (talk) 05:22, 13 March 2011 (UTC)


 * The TEPCO press releases have consistently referred to this incident as having taken place at the Daini (not Daiichi) plant. It seems pretty clear that the secondary sources which mention a death are wholly reliant on the TEPCO reports for the information in question - they have simply confused the two locations. —Preceding unsigned comment added by 82.132.248.226 (talk) 06:18, 13 March 2011 (UTC)


 * Sorry, yes, you are correct, anon, the crane operator who died was at Fukushima Daini. TEPCO press release on the matter. --Zippy (talk) 07:08, 13 March 2011 (UTC)

Significance of radiation levels
160 people have been subjected to overdoses of radiation. http://www.spiegel.de/international  --78.55.197.3 (talk) 04:45, 13 March 2011 (UTC)

The IAEA has published guide for the assessment of accidents and the protection of the public

INTERNATIONAL ATOMIC ENERGY AGENCY, Generic Assessment Procedures for Determining Protective Actions during a Reactor Accident, IAEA-TECDOC-955, Vienna (1997). http://www.iaea.org/ns/tutorials/regcontrol/refs/29generic.pdf

The threshold for evacuation is a MEASUREMENT of external gamma dose rate of 1 mSv/h (OIL1 in Procedure B1, p. 162).

So a measurement of 69 nanogray/hour at the main gate = 69 nanosievert/hour = 0.0069% of the evacuation level. 385.5 microGy/h at the main gate = 0.385 mSv/h = 38% of the evacuation level at the main gate. At Fukushima, a few km away, it is probably quite a bit lower. So, the radiation levels OUTSIDE the plant are low to very low. Inside, it's another story... —Preceding unsigned comment added by 80.123.223.150 (talk) 20:56, 12 March 2011 (UTC)

Please stop using PRESENT TENSE
Some parts of the article (especially 'Explosion', which I corrected, but may get reverted by someone) were written in the present tense - which as well as being un-encyclopedic, will look stupid by even tomorrow. — Preceding unsigned comment added by Malau (talk • contribs) 11:05, 12 March 2011 (UTC)
 * Chances are that there are many Japanese attempting to edit, possibly relaying the characteristics of their language into English. -Mardus (talk) 11:53, 12 March 2011 (UTC)
 * I invite you to edit the page to fix problems. —Ben Kovitz (talk) 07:25, 13 March 2011 (UTC)

Disappointing
As someone who is at least marginally qualified to interpret information about the design of the plant, I was extremely disappointed with both the tone and content of the wikipedia article about it. The article is full of the latest information, appropriate for keeping on top of things. The problem, paraphrasing Don Knuth, is that it's not wikipedia's job to keep on top of things: this site is supposed to be an encyclopedia, which is appropriate for getting to the bottom of things. And it has failed at that. The article uses the acronym BWR, implying a single loop design, gives the date 1966 and mentions GE, which built single loop reactors in that era as opposed to the Westinghouse and B&W double loop designs. But it doesn't really say any of this, nor does it even provide references to other articles that would help. Google news helps me keep on top of things better than wikipedia ever will; if wikipedia wants to keep adding value, it needs to get out of this business. —Preceding unsigned comment added by 71.59.236.139 (talk) 05:42, 12 March 2011 (UTC)
 * What would you have us do? --Kiz o r  07:09, 12 March 2011 (UTC)
 * And by not fixing and sourcing it, you are part of the problem. StrangeWill (talk) 07:29, 12 March 2011 (UTC)
 * True, but editing is hard enough for newcomers. He can hardly be faulted for refusing to participate in an article about an ongoing disaster. It's a valid subject, and makes for a doable article, and "getting out of this business" would mean ridiculously counterproductive strong-arm tactics, but it can make editing feel rather like being on the wrong side of a tumble dryer. --Kiz o r  10:37, 12 March 2011 (UTC)

The writer is conflating Boiling Water Reactors (BWRs) manufactured by GE, and Pressurized Water Reactors (PWRs) as manufactured by Westinghouse, B&W and Combustion Engineering. The number of recirculation loops in any of the designs really doesn't have much relevance to the story at hand. It's like fretting about the number of staterooms that the Titanic has, as you see the stern slowly slip below the waves. — Preceding unsigned comment added by Topamo (talk • contribs) 15:30, 12 March 2011 (UTC)

Light Water
Please consider identifying this reactor broadly as a Light Water Reactor at the very beginning of this article (if that is in fact what it is) for neophytes seeking information about the plant. Thanks AnnaZed 16:40, 12 March 2011 (UTC) — Preceding unsigned comment added by AnnaZed (talk • contribs) ✅ L.tak (talk) 16:47, 12 March 2011 (UTC)

Please remove reference to a cesium rod
There is no such thing as a cesium rod in a BWR. There are fuel rods that are hot from the heat generated by the radioactive decay of the fission products (decay heat). Some of the fission products are isotopes of cesium, but there is also a whole range of chemicals inside the rods. —Preceding unsigned comment added by 80.123.223.150 (talk) 07:33, 12 March 2011 (UTC)
 * it's out now... L.tak (talk) 08:29, 12 March 2011 (UTC)

There is another error: "electric power for the cooling turbine" is clearly wrong as the turbine is the passive element and does not generate heat. It is the fuel rods or elements (mostly uranium oxide packed in zirconium capsules that are packed into hollow tubes that are mechanically adjusted to get criticality) that need cooling. Zirconium metal in contact with hot water can release hydrogen and this gets messy. The shutting down is usually done by first disconnecting from the grid, shutting down the turbine/ generator and the raising of the fuel rods to get the rector to a subcritical condition. In an emergency, if the last step fails, the heat need to be removed by just pumping water. A 1000MW reactor needs about 1 cubic meter of water boiling off per second. Hence the need to pump enormous amounts of water...59.93.96.133 (talk) 18:34, 12 March 2011 (UTC)

Removed part
I removed this part (1/2 times now -the first time I think it was wikipedia and a weird sort of edit conflict, but anyway- so I'll stop):


 * In addition to the reactor cores, the storage pool for highly radioactive irradiated nuclear fuel is also at risk. The pool cooling water must be continuously circulated. Without circulation, the still thermally hot irradiated nuclear fuel in the storage pools will begin to boil off the cooling water. Within a day or two, the pool’s water could completely boil away. Without cooling water, the irradiated nuclear fuel could spontaneously combust in an exothermic reaction. Since the storage pools are not located within containment, a catastrophic radioactivity release to the environment could occur. Up to 100 percent of the volatile radioactive Cesium-137 content of the pools could go up in flames and smoke, to blow downwind over large distances. Given the large quantity of irradiated nuclear fuel in the pool, the radioactivity release could be worse than the Chernobyl nuclear reactor catastrophe of 25 years ago.

L.tak (talk) 22:03, 11 March 2011 (UTC)
 * 1 because it is a very long quotation which is not really useful, but
 * secondly because it is a scenario by an anti-nuclear expert.
 * 3: I think we should focus here on the facts and immediate risks rather than discuss risks if events don't unfold positively in the next days in worst case (the name given in the article it cites....). Views welcome!
 * That's perfectly reasonable. -Theanphibian (talk • contribs) 22:07, 11 March 2011 (UTC)
 * I agree with your decision "up to 100%." -- 76.115.3.200 (talk) 23:20, 11 March 2011 (UTC)
 * Agree, particularly also because the claim that the storage pools are located outside the containment is unsourced and possibly false. --Schmassmann (talk) 12:53, 12 March 2011 (UTC)

No, spent fuel pools are indeed outside of containment. While I can't speak to all the consequences of a loss of pool cooling, as cited above, the pool will boil, and water will be lost. Power plants have contingencies for hosing in water in emergencies. If they are flooding containment - as seen in some reports - they have water and the capability to pump it. Part of that capability would logically be used to ensure the spent fuel isn't uncovered. — Preceding unsigned comment added by Topamo (talk • contribs) 15:20, 12 March 2011 (UTC)

You are assuming that the same system that is used to inject seawater into the containment can provide cooling to the fuel storage pool. This is absolutely illogical. I guess it makes sense to you because both involve water and safety at a nuclear plant, but the requirements of both of those safety systems would dictate that separate systems are used. Just because they have the ability to power one set of pumps does not mean that they have the capability yet to restore pool cooling. It is possible that they have restored their local power distribution system sufficiently to provide power to the pool, but it is by no means a logical consequence.98.240.67.27 (talk) 17:40, 12 March 2011 (UTC)

Well, yes, in Design Basis space, where life is nice and organized, you have separate systems with separate functions. From all outward appearances, though, Fukushima is working under Severe Accident Guidelines where, in essence, you do anything and everything to keep the core and fuel pool under water. Systems have emergency cross-ties to help accomplish that. They can bring in diesel-power pumps and hoses. Or schlep in cases of Perrier or Evian. Ultimately, water is water. With your back against the wall, It is absolutely illogical to constrain yourself to the design basis functions of your systems.Topamo (talk) 00:00, 13 March 2011 (UTC)

Dates
The is hour that don't have date with it. For now, we can assume it is march 11 (GMT, march 12 local time). I propose to add date, and to convert all GMT time to local time.

199.89.103.13 (talk) 22:34, 11 March 2011 (UTC)
 * go ahead, but it might be tricky with so many reversions at the moment... L.tak (talk) 22:53, 11 March 2011 (UTC)
 * That will also change the date of many press stories, so I don't recommend it, due to the date you put in not matching the date on the site of, say the New York Times or a London paper, making it difficult to verify or find the reference later. Edison (talk) 23:25, 11 March 2011 (UTC)

I converter time to JST in the article, but not in the reference. 199.89.103.13 (talk) 23:33, 11 March 2011 (UTC)

Useful news resources for today's incident
So far, much of the mainstream media (major newspapers, broadcasters, etc.) coverage of the incident following the earthquake has been garbled and contradictory, perhaps because the reporters don't yet fully understand the technology they're reporting on. World Nuclear News is published by the World Nuclear Association, an international industry trade group; the target audience is the nuclear industry, not the general public. Here's a link to their current coverage: Presumably the mainstream media will improve their coverage in the next day or two as they come to better understand the technical issues, but for now, this is the most reliable article I've found. It appears to be updated every several hours.

-- A. B. (talk • contribs) 23:57, 11 March 2011 (UTC)


 * Here is a link to Tokyo Electric Power Company's news release page, which is issuing more or less hourly updates. Most of the coverage in the mainstream media appears to be based on these releases; as well, the statements by the Japanese government pretty much reflect the same information. Realistically, there are not going to be any other, independent primary sources of information at this point that are not based on information coming from the engineers on site.


 * -- A. B. (talk • contribs) 00:13, 12 March 2011 (UTC)


 * Here is the Japanese Nuclear Safety Commission's English language site; as of this point, they are not posting anything on the incident in English:
 * http://www.nsc.go.jp/NSCenglish/index.htm
 * I have no idea what they're posting in Japanese:
 * http://www.nsc.go.jp/index.htm


 * This is the Japanese Prime Minister's web site in English:
 * There is a page on that site with links to the Prime Minister's statements on the 11 March earthquake, including the problems with TEPCO's reactors:
 * As of now (00:30, 12 March 2011), that site's English releases do not yet reflect the most recent events (such as evacuation orders).
 * My sense is that TEPCO and the government have been slow and cautious in releasing information on what's going on.
 * -- A. B. (talk • contribs) 00:39, 12 March 2011 (UTC)
 * The TEPCO 7 AM press update says their "monitoring car" detected elevated levels of radioactive material "Iodine etc." Would there normally be detectable levels of radioactive Iodine? An "elevated level" could be .01% above normal background. A China Syndrome could also produce "elevated radioactive Iodine levels" much higher, so they become a health hazard. Is "elevated" a term of art in nuclear safety, meaning a significantly above normal level? We should restrain anyone's going beyond official statements and reliable press coverage, in the article text. Edison (talk) 00:51, 12 March 2011 (UTC)
 * The English language version of that news release is a little ambiguous -- it refers to monitoring of radiation (Iodine, etc). That could mean radioactive iodine levels have gone up or that radiation levels in general have gone up. The presence of radioactive iodine does not indicate a China syndrome is imminent -- just that the zircalloy cladding somewhere on a fuel element has been damaged, exposing the uranium fuel underneath. Radioactive iodine is a fission product entrapped in the uranium fuel and is released into the coolant when this happens. See our Nuclear fission product article for a good write-up on fission products. Any radioactive iodine would still not reach the environment unless either the reactor piping was breached, inadvertently releasing steam or liquid coolant (water), or (more likely), some steam was deliberately vented to reduce pressure. So the presence of radioactive iodine could indicate anything from a small defect to a big problem.
 * I think the ambiguities here are typical of the early hours of a nuclear incident in a foreign country being reported by a non-technical press corps. The fact that this is going on during a major disaster makes it that much more difficult for the press to focus in on getting themselves up to speed on the problem and asking the right questions. -- A. B. (talk • contribs) 01:48, 12 March 2011 (UTC)
 * The English language version of that news release is a little ambiguous -- it refers to monitoring of radiation (Iodine, etc). That could mean radioactive iodine levels have gone up or that radiation levels in general have gone up. The presence of radioactive iodine does not indicate a China syndrome is imminent -- just that the zircalloy cladding somewhere on a fuel element has been damaged, exposing the uranium fuel underneath. Radioactive iodine is a fission product entrapped in the uranium fuel and is released into the coolant when this happens. See our Nuclear fission product article for a good write-up on fission products. Any radioactive iodine would still not reach the environment unless either the reactor piping was breached, inadvertently releasing steam or liquid coolant (water), or (more likely), some steam was deliberately vented to reduce pressure. So the presence of radioactive iodine could indicate anything from a small defect to a big problem.
 * I think the ambiguities here are typical of the early hours of a nuclear incident in a foreign country being reported by a non-technical press corps. The fact that this is going on during a major disaster makes it that much more difficult for the press to focus in on getting themselves up to speed on the problem and asking the right questions. -- A. B. (talk • contribs) 01:48, 12 March 2011 (UTC)

Ongoing updates on the International Atomic Energy Agency site: The IAEA's updates are based on information from the Japanese safety agency. -- A. B. (talk • contribs) 01:55, 12 March 2011 (UTC)


 * Could we have an actual radiation measurement added to this article please? My back-of-the-envelope calculation is that "1000x background" is approximately 0.5 REM per hour, about 10% of the lifetime dosage acceptable for nuclear power plant workers (5 REM) in the USA but well below immediately dangerous levels (i.e. 70 to 100 REM). 71.198.27.62 (talk) 02:21, 12 March 2011 (UTC)
 * You raise a good question but so far the English sources that I have seen are only ambiguously reporting "1000 times" with no elaboration as to what the actual does is. Are they reporting gamma radiation coming through the shielding? Or airborne contamination levels? And what's the "normal" they're comparing this to? It's unclear at this point. I'm not sure the press really understands the technical details of what they're reporting. Likewise, I'm not sure TEPCO's translators understand the technical details of what they're posting in English. -- A. B. (talk • contribs) 02:40, 12 March 2011 (UTC)


 * A new news article worth reading:
 * I'm going offline now and I think L.tak is also -- it would be helpful to get some other editors watching and updating this article as events unfold.
 * Thanks, -- A. B. (talk • contribs) 03:01, 12 March 2011 (UTC)
 * Thanks, -- A. B. (talk • contribs) 03:01, 12 March 2011 (UTC)


 * Many of the English-language media are quoting Kyodo News agency's reports; you can find English versions of them at:
 * http://english.kyodonews.jp/
 * They appear to basically be rehashing the TEPCO and IAEA information cited above.


 * Various Western media outlets are also calling in technical pundits and academics to fill in the blanks in their coverage; their comments are ranging in style from "there's no real problem" to "this is the Apocalypse". It's all nothing but speculation for now, regardless of the pundits' supposed expertise; we should avoid adding this stuff until further hard information comes out of the Fukushima plants. -- A. B. (talk • contribs) 03:21, 12 March 2011 (UTC)
 * -- A. B. (talk • contribs) 03:21, 12 March 2011 (UTC)

Unit 4?
was in maintenance we thought... But still cooling problems seem to have occurred? http://www.tepco.co.jp/en/press/corp-com/release/11031214-e.html Would that make sense? L.tak (talk) 02:29, 12 March 2011 (UTC)
 * hm, that was Fukushima II Nuclear Power Plant (daini).... L.tak (talk) 02:35, 12 March 2011 (UTC)

Conflicting information
TEPCO press releases indicate core cooling initially occurring with RCIC (Reactor Core Isolation Cooling) and then using the makeup system (non-emergency system). This would be 'normal' following a reactor scram. The indication also is that suppression pool temperature went over 100 degrees, probably indicative of relief valve operation, also somewhat 'normal' in a scram situation of this type. The high suppression pool temperature seems to indicate that the suppression pool cooling mode of Low-Pressure Coolant Injection (LPCI) has not been able to be entered for some reason. Nothing indicative of truly 'major' damage or malfunction. At most a hint of a possible small steam leak inside primary containment. The radiation detected is a mystery. TEPCO press releases indicate no stack or effluent monitoring detection. There is no mention of abnormal containment radiation monitoring system detections. One monitoring station detecting something could be a fluke. Earthquakes have been known to release naturally-occuring radiation, such as radon gas. If there is no abnormal radiation in containment, where would this detected radiation be coming from? —Preceding unsigned comment added by 70.44.68.140 (talk) 03:14, 12 March 2011 (UTC)
 * What exactly is the "makeup system" (referred to in the TEPCO English PR as "Make-up Water Condensate System", which doesn't appear to be a standardized term referring to GE BWR designs)? Where does it take its water from? The suppression pool or from outside the containment? Where can it take pump power from? Also, it appears TEPCO acknowledges (as of March 12th 10 AM JST) release of radioactive gases (or particle contaminats in vented air) and that two different monitoring systems detect elevated radiation levels outside the Daiichi (Fukushima I) plant as follows:
 * Measurement of radioactive material (Iodine, etc.) by monitoring car indicates increasing value compared to normal level. One of the monitoring posts is also indicating higher than normal level. We will continue monitoring discharge of radioactive material from exhaust stack and discharge canal, etc.
 * Considering the increasing pressure with in the reactor containment vessel of Unit 1, the national government has instructed us to implement measures to reduce the pressure of the reactor containment vessel (partial discharge of air containing radioactive materials) in order to fully secure safety.
 * I was under the impression that the suppression pool design (Mark II? for Daiichi/Fukushima I Unit #1) was intended to prevent any need to vent readioactive steam to the outside air. What kind of "containment" is it, if they need to vent outside of it when just 100°C is exceeded? I also thought that the suppression pool had air scrubbers to remove airborne contaminants from the atmosphere inside that structure. Do these need outside power to operate?


 * All considered, these reports are indeed very conflicting, because by IAEA standards any intentional release of radioactive substances from a triple redundant containment is an extremely serious situation, indeed an accident (INES Level 4 at this stage) 85.156.224.62 (talk) 04:43, 12 March 2011 (UTC)
 * Aiui, the pressure chamber is designed to prevent water boil to 148C, and is a closed system. That would be an atmospheric pressure of 66 psi/4.6 bar. If the pressure had risen to 1.5x the normal inside the chamber as reported, 99 psi/6.9 bar, it might increase the risk of a catastrophic failure of the pressure chamber if the temperature continued to climb and achieved a boiling point&mdash;164C (at which point the pressure would presumably increase rapidly.) - Amgine (talk) 05:08, 12 March 2011 (UTC)

"...the Nuclear and Industrial Safety Agency announced that part of a cesium rod appeared to have melted,..." Since cesium melts at 28C (i.e., in your hand) the quality of both information and reporting seems to be really poor. 68.110.169.4 (talk) 06:11, 12 March 2011 (UTC)
 * Obviously there are no such things as "cesium rods" inside the reactor, so I don't see the point in replicating such an error in reporting in the article. What is really meant, is that the detected caesium-137 levels indicate that at least one fuel rod has melted, which is pretty cautious statement. If melting tempertures have been achieved, it would stand to reason that several fuel rods have melted already, at least partially.


 * It's also interesting that only IAEA used to claim that any venting from Daiichi #1 was to be filtered with radioactive elements being retained in containment, while TEPCO never made such a claim. Also, the latest IAEA alert no longer makes this filtration claim. This clarifies the situation somewhat, because unfiltered release of primary containment steam would explain the onsite detections of radiation release. Just to recap, latest TEPCO reports state that Daiichi #1 has released such vapor and Daiichi #2 and Daiichi #3 are preparing for the capability to release. Also, Daini (Fukushima II plant some 10 km south of Daiichi) reactors #2 and #4 have finished preparations for release, while #1 is still preparing and #3 achieved "cold shutdown". 85.156.224.62 (talk) 08:11, 12 March 2011 (UTC)


 * Given the reported explosion and massive cloud of "white smoke" (steam?) surrounding Daiichi #1 that are now filtering in, I expect that we're looking at a meltdown somewhere in the INES Level 5 or Level 6 range at this point. I won't put that into the article, because it would be OR, but in short, things just went to shit.  rdfox 76 (talk) 08:17, 12 March 2011 (UTC)
 * Agreed, things really took a turn for the worse. It might be interesting to look at the 5 day weather forecast for wind directions. Nuclear safety regulator pundits are already speculating with the possible fallout scenarios. 85.156.224.62 (talk) 08:28, 12 March 2011 (UTC)
 * From BBC: Japan's NHK TV showing before and after pictures of the Fukushima-Daiichi plant. It appears to show that the outer structure of one of four buildings at the plant is no longer there. Ouch! I'll try to verify that, but it's unlikely it could be some other building, such as the turbine hall... 85.156.224.62 (talk) 08:32, 12 March 2011 (UTC)
 * If it's a reactor building, like I suspect, then this is at least INES Level 6. The only positive is that it's on the downwind side of the land mass, so most of the fallout will be over open ocean... rdfox 76 (talk) 08:54, 12 March 2011 (UTC)
 * And Reuters is now saying that NHK is reporting the entire outer structure has been blown off the containment building for reactor #1. Holy shit.  rdfox 76 (talk) 09:00, 12 March 2011 (UTC)
 * Yep, it's Chernobyl II, after seeing a video of the actual explosion and how high pieces of thigh concrete structure went up in the air, I now believe only a steam explosion inside the RPV could have caused that. Failure of the torus/pressure suppression pool should not have been able to release that much energy. 1 Sv per hour measured externally so soon after the explosion also confirms that most of the core is dispersed already. Earlier TEPCO reported that one plant operator had dosimetered 100 mSv, but I would expect there to be deaths from direct prompt radiation poisoning after this event.85.156.224.62 (talk) 09:08, 12 March 2011 (UTC)
 * It appears there was a "dot error" in that radiation measurement, now they report 1,015 (one thousand fifteen) microsieverts per hour, in other words 1 mSv, which is the ICRP yearly limit of exposure. This level of radiation is not that significant and doesn not indicate that the core is exposed (but doesn't rule it out either, since we don't know how close that measurement is from). 85.156.224.62 (talk) 09:43, 12 March 2011 (UTC)
 * It's really sad to see this happen again and with the energy/climate change politics situation today, this could have very unfortunate long term effects for people all over the world. One thing is sure though, the Japanese are very good at organizing response to things like this and should avoid the errors made by Ukraine in 1986. Ofcourse, they have a lot of things to worry about in the aftermath of the quake and tsunami, but this reactor accident will surely dominate following days and weeks of disaster recovery. Hopefully the other reactors will hold long enough to be cooled down properly. Daiichi #1 was the oldest (1971) and probably with the weakest containment and emergency system design. 85.156.224.62 (talk) 09:08, 12 March 2011 (UTC)
 * RT has decent live coverage, with attention to Sakhalin and the Kurile Islands; given the Soviet experience with Chernobyl, it's well informed. --Nachthexen (talk) 09:34, 12 March 2011 (UTC)

Formatting
In the first section, "Reactors on site", a graphic called "Aerial view of the plant" obscures the table listing the reactors. MichaelAaronson (talk) 04:53, 12 March 2011 (UTC)
 * that often depends on resolution etc; is it better now? L.tak (talk) 08:25, 12 March 2011 (UTC)
 * Yes, the problem seems to be fixed. Thank you. MichaelAaronson (talk) 00:56, 13 March 2011 (UTC)

Normal operating pressure
The article currently states "At 2:00 JST, the pressure inside the reactor was reported to be 600kPa (6 bar or 87 psi), 200 kPa (2 bar or 29 psi) higher than under normal conditions." Can that be right? Boiling water reactor states that the cooling water of a BWR is normally kept at about 75 bar. 4 bar steam doesn't sound very useful for driving a H.P. turbine. -- 119.31.121.88 (talk) 08:16, 12 March 2011 (UTC)
 * the big question of course is: where in the system are those pressures taken? However it comes from WNN, which look knowledgeble to me... L.tak (talk) 08:27, 12 March 2011 (UTC)
 * The source speaks of the "pressure inside the containment of unit 1", so the pressures are almost certainly of the containment building and not the reactor vessel itself, as currently implied in the article. -- 119.31.121.88 (talk) 10:19, 12 March 2011 (UTC)

Edit request
Please change all GMTs to JST (for consistency). 220.100.15.15 (talk) 08:30, 12 March 2011 (UTC) ✅ (added JST and kept GMT so GMT serves for fact checking with sources as well) L.tak (talk) 12:12, 12 March 2011 (UTC)
 * OK thanks. Perhaps a detail that we can discuss later. 220.100.15.15 (talk) 12:47, 12 March 2011 (UTC)

Please add link which shows "Simplified Reactor Cooling System Flow Diagram" above list of reactors table http://www.icjt.org/plants/uni/e/uni194e.html 70.138.99.110 (talk) 13:28, 12 March 2011 (UTC)

It may have just blown up
This appears to be a video of it blowing up, released 15 mins ago: http://www.twitvid.com/LICNU Any news of this on English-language media yet? Buckethed (talk) 08:33, 12 March 2011 (UTC)
 * NHK World English service has reported the explosion and is showing live video which clearly shows that Daiichi #1 outer containment building has partially collapsed, with only remains of one wall remaining and that 1,050 mSv of radiation level has been measured (per hour?, no mention of time interval). 85.156.224.62 (talk) 08:41, 12 March 2011 (UTC)

All of the news agencies covering live are saying that the plant is possibly undergoing a meltdown. Should this be reported? 198.96.35.248 (talk) 08:37, 12 March 2011 (UTC)
 * Probably not yet. While the damage is self evident and it's difficult to explain it without a steam explosion resulting from a full meltdown, that's something we need "expert confirmation" for. 85.156.224.62 (talk) 08:44, 12 March 2011 (UTC)

Not a viable source, but looking at this more detailed video, it's clear that a major steam explosion destroyed the reactor building, and may well have ruptured the containment vessel. rdfox 76 (talk) 09:09, 12 March 2011 (UTC)
 * Caution advised. One cannot view a video and make aconclusion. Remember "wp:No Original Research" - 220.101 User talk:220.101.28.25\ 09:30, 12 March 2011 (UTC)
 * I can speculate a bit here; I'm not going to use this in the article without a reliable source. rdfox 76 (talk) 09:41, 12 March 2011 (UTC)
 * Concur. Indeed something has exploded on a violent fashion. But was it the "reactor building". We can't assume. That said, viewres pay attention at 00:47 where they replay a zoomed in view. Worrying. - 220.101 User talk:220.101.28.25\ 09:48, 12 March 2011 (UTC)
 * That's what I meant; as this isn't article space, a *little* speculation is acceptable. (I was basing the identification of the reactor building on the before-and-after shots shown by NHK, and reports by other sources.) Since I need sleep, we'll hopefully have a better handle on this in the morning.  It's definitely safe to say that the shit has hit the fan...  rdfox 76 (talk) 09:54, 12 March 2011 (UTC)
 * We just have too keep in mind that there are many causes of 'explosions'. I don't know what volatile chemicals may be used in a Nuclear facility. Adding my own own observation, (OR!) TV news in Sydney showed the structure after the smoke had cleared. It appeared to show the buildings internal frame left after the explosion. Does not seem consistent with a reactor 'containment building'. - 220.101 User talk:220.101.28.25\ 10:11, 12 March 2011 (UTC)
 * GE Mark I BWRs don't have an actual reinforced outer containment building, they have a "reactor hall" of the same type of construction as RBMK (Chernobyl type), so it's not really that strong. But even real outer containment buildings could leave such internal reinforcement structures remaining after a large overpressure event. IOW, the only thing you can determine from the video of the actual explosion with the pieces flying wide and far, and the remains now standing, that a very high energy event occurred, whether that was a hydrogen or steam explosion, major damage has been caused and that the integrity of the RPV is in very serious doubt. 85.156.224.62 (talk) 10:24, 12 March 2011 (UTC)

BBC now has the explosion video and some commentary: http://www.bbc.co.uk/news/world-asia-pacific-12721498 ... Also, here is the jet stream path to North America: http://www.stormsurfing.com/cgi/display_alt.cgi?a=npac_250 ... Here is the Google Maps image of the (previously intact) reactor: http://maps.google.com/maps?t=h&q=37.421389,141.0325&ie=UTF8&ll=37.42135,141.032417&spn=0.005871,0.008948&z=17 --Radical Mallard (talk) 10:16, 12 March 2011 (UTC).


 * Well, based on the aerial photo on this page (position of antennas, mostly) & the video at BBC, i can asume containment building at reactor number one is gone. I just hope the pressure vessel is intact, if the radioactive material exploded, we may be looking at 21st century's Chernobyl. I won't make any edit per WP:NOR, but just wanted to comment this --190.189.11.201 (talk) 10:37, 12 March 2011 (UTC)

Live up to date newscasting from BBC can be watched here: http://www.bbc.co.uk/news/world-asia-pacific-12710020 --Radical Mallard (talk) 10:43, 12 March 2011 (UTC)

Additional info on the explosion can be found in the last few paragraphs here (http://news.sky.com/skynews/Home/World-News/Video-Fukushima-Nuclear-Fallout-How-Bad-Could-It-Get/Article/201103215950994?lpos=World_News_Carousel_Region_2&lid=ARTICLE_15950994_Video%3A_Fukushima_Nuclear_Fallout%3A_How_Bad_Could_It_Get) Somebody find something useful? — Preceding unsigned comment added by Serazahr (talk • contribs) 12:03, 12 March 2011 (UTC)

We really can't assume the containment is gone. If it was a hydrogen gas explosion in the outer building, that could have blown off the metal covering on that building (the frame's clearly still there) without rupturing the very heavy and strong containment vessel within. There's a one frame bright flash in the slow-motion close up video, and a supersonic shockwave, both of which indicate hydrogen explosion. An internal pressure explosion inside the containment dome would not have had a shockwave or bright flash. It might be damaged, but wait for the Japanese to provide some actual information on that, please. The video isn't evidence one way or the other. Georgewilliamherbert (talk) 12:16, 12 March 2011 (UTC)

Article now only says "Unit 1 has blown up", no citations...?
I was just monitoring the article & Talk page (among other places) to see what was going on re: the explosion, and noticed that the article now consists of a photo of a huge black smoke plume along with the note that Unit 1 has "blown up" - no article references or citations. Could someone that knows jack about the article topic please do...fix...er, whatever phrase would be relevant? Thanks... --☥ Xyzzy Avatar ☥ 09:25, 12 March 2011 (UTC) — Preceding unsigned comment added by Xyzzyavatar (talk • contribs)
 * which sentence exactly was not sourced? L.tak (talk) 09:28, 12 March 2011 (UTC)
 * "After the March 11, 2011, earthquake, unit 1 has blown up." -- Wait, no, I just refreshed the article again, and it appears to be restored. That one sentence was pretty much all that was appearing. ☥ Xyzzy Avatar ☥ 09:34, 12 March 2011 (UTC)  — Preceding unsigned comment added by Xyzzyavatar (talk • contribs)

Fair use photo?
There's a fair-use image File:2011-03-12 1800 NHK Sōgō channel news program screen shot.jpg of before-and-after explosion, captured from Japanese television. I think this is able to be used here on this article. A new FUR needs to be written on the file description page to allow this. 184.144.160.156 (talk) 10:01, 12 March 2011 (UTC)


 * The image has been nominated for speedy deletion. 184.144.160.156 (talk) 11:00, 12 March 2011 (UTC)

Here's a photo on Panarama. Unit 1 is on the left. http://www.panoramio.com/photo/46503912 It is the 3rd oldest and 3rd smallest unit in the country. Here are exact coordinates of unit 1: 37°25'23" N 141°01'58" E

Ywaz (talk) 11:08, 12 March 2011 (UTC)


 * That is an "(C) All rights reserved" photo, so would also need a Fair-Use-Rationale, and a copyright notice. If you upload it, make sure it is tagged properly, and associate it with this article on the FUR. 184.144.160.156 (talk) 11:43, 12 March 2011 (UTC)

Evacuation zone expanded to 20 km
Reuters is reporting that the evacuation zone has been updated to 20 km, please add. Reuters link


 * ✅ L.tak (talk) 12:10, 12 March 2011 (UTC)

International Nuclear Event Scale
Does anyone know what this event's current rating is on the International Nuclear Event Scale? Its listed in the see also section, but I see no indication of where this event currently ranks on their scale. Some input here would be nice - assuming that anyone in authority at the INES monitoring group has issued a statement for this as of now. 75.31.185.120 (talk) 10:38, 12 March 2011 (UTC)
 * INES doesn't work like that. They review events afterwards. Sorry, no ticker-bar, no blinking lights. What you're asking for is speculation anyway. We don't know much. However, it'll be at least a 5, likely a 6, maybe a 7. --91.32.100.122 (talk) 10:48, 12 March 2011 (UTC)
 * INES tracks how much the mess affects its environment, not the severity of the mess in and of itself. (A case of nuclear material falling into squatters' hands has scored higher than some meltdowns.) It seems doubtful that a rating would be announced before things have settled down. Once it is, expect it to be ridiculously easy to find. --Kiz o r  10:51, 12 March 2011 (UTC)
 * Oh, Ok: this is sort of like the Fujita Scale they use in the United States for Tornado strength measurements. Its issued after the tornado, not during the tornado itself. So I guess now we play the waiting game... 75.31.185.120 (talk) 10:54, 12 March 2011 (UTC)
 * Sounds just like it, yeah. --Kiz o r  11:00, 12 March 2011 (UTC)

I believe this is a number 4, based on what BBC said.--Radical Mallard (talk) 18:22, 12 March 2011 (UTC)

Add NISA as source please
Please add http://www.nisa.meti.go.jp/english/ to the external links. That is the website of the Japanese authority concerned with reactor safety and they currently release frequent updates on the state of affairs. 80.216.29.79 (talk) 10:45, 12 March 2011 (UTC)
 * Done. Where do I go to get that nifty green mark that is usually used with fulfilled edit requests? --Kiz o r  11:52, 12 March 2011 (UTC)

✅, like this? ;-) L.tak (talk) 12:08, 12 March 2011 (UTC)
 * Thanks. ✅. --Kiz o r  12:13, 12 March 2011 (UTC)

New Wikinews
There's a new article being written on Wikinews, Explosion at earthquake damaged Fukushima nuclear power plant. 184.144.160.156 (talk) 10:58, 12 March 2011 (UTC)

Proposed move of nuclear incident material
In light of little tour around the site which seems to suggest that nuclear power plants and nuclear incidents should be treated separately, I'm proposing that the bulk of the material in the quake section be broken out into a separate article, something like Fukishima I Nuclear Incident. This will allow for better coverage of what by all rights is at the point a nuclear incident and will allow for a more accurate title of the event. To provide an example, the Chernobyl incident has its own article independent of the power plant, as does the Three Mile Island incident, which has an article separately maintained from the plant article. TomStar81 (Talk) 11:14, 12 March 2011 (UTC)
 * It is clearly a long-term or even middle-term obvious editorial decision. I am not sure this is a good short-term bet : the article about the power plant is not too long, and while the situation evolves very quickly, it is easier to have only one article to watch and make evolve. To say it in a short way, my opinion is not a strident "no", but a "please wait a week or two". French Tourist (talk) 11:22, 12 March 2011 (UTC)
 * More like a "Wait and see", that seems to sum up the general position on events like this. I'm not proposing that we make such a move right this exact second, but perhaps in another two or three days. Its going to happen eventually, since there will be a rather extensive review of this incident at nearly all levels of the government and nuclear control bodies, and that alone will push us to the brink of what can be comfortably accommodated here. At the moment I am more interested in gaining consensus for a move when the time is judged to be right for such a move, though I concede that at the moment this is somewhat in violation of WP:CRYSTAL. TomStar81 (Talk) 11:29, 12 March 2011 (UTC)
 * That will happen, but it should wait until things settle down. Splitting an article takes some time, care, and a good grasp on the subject. Articles on large ongoing events are chaotic enough that a split is prone to causing a loud and pointless edit war. In fact a split was attempted earlier today, and promptly undone. Best to wait, the need isn't pressing. This article is adequate for our current needs, and settling on a title could open a whole new can of worms. --Kiz o r  11:31, 12 March 2011 (UTC)
 * Fukushima I disaster already exists. - 220.101 User talk:220.101.28.25\ 12:28, 12 March 2011 (UTC)

Radiation level before explosion
From recorded video feed of NHK World: "Fukushima Prefecture says a radiation level of 1,015 mircrosieverts [sic] per hour has been measured near the Fukushima Number 1 nuclear power station. One hour of exposure to this amount of radiation is equivalent to the permissible amount of radiation an ordinary person receives in one year" 80.248.244.32 (talk) 11:41, 12 March 2011 (UTC)

An english link: http://www3.nhk.or.jp/daily/english/12_51.html 80.248.244.32 (talk) 11:48, 12 March 2011 (UTC)

I just noticed that this was observed *before* the explosion, not after (see that link above) 80.248.244.32 (talk) 11:57, 12 March 2011 (UTC)

Population
Please notate population in/round the town of okona (sp) and the county/prefecture, etc.--how many people live in the evactuated 20-mile around zone? 149.6.120.130 (talk) 11:41, 12 March 2011 (UTC)
 * done L.tak (talk) 12:04, 12 March 2011 (UTC)

Meltdown
Here is a source for the Meltdown being confirmed (German) http://www.tagesschau.de/nachrichtenticker/ — Preceding unsigned comment added by Serazahr (talk • contribs) 11:39, 12 March 2011 (UTC)
 * Not to get anal here but if you're going to add the material to the english wikipedia could you try and find an english source? If we cite the info without one I fear all we will do is set off an international panic. TomStar81 (Talk) 11:44, 12 March 2011 (UTC)

Remove unsourced material
Remove this stuff ASAP. 220.100.15.15 (talk) 11:40, 12 March 2011 (UTC)
 * done, see discussions below

Confirmation of nuclear meltdown?

 * Japanese authorities have officially confirmed a nuclear meltdown.

I'm not against having this material in the article, but could we at least source it to an English page? Being that its in a foreign language and that this kind of information could/will set off a panic of some sort I;d prefer the people be able to read it in English to confirm the report with their own eyes. WIKI TURNING SIMPLE MINDED? NO FOREIGN LANGUAGE LINKS? SMACKS OF ANGLOPHILE. BAD IDEA.

TomStar81 (Talk) 11:47, 12 March 2011 (UTC)
 * Fully agree. I can also imagine many temp-related things being translatable (incorrectly) as meltdown, so we should be careful... L.tak (talk) 11:50, 12 March 2011 (UTC)

The top of the page says:
 * Eilmeldung
 * Kernschmelze in japanischem AKW bestätigt
 * Die japanischen Behörden haben offiziell bestätigt, dass es im AKW Fukushima eine Kernschmelze gegeben hat. Das berichtet ARD-Korrespondent Hetkämper.

meaning: breaking news. nuclear meltdown in japanese nuclear plant confirmed. The janapenes authorities have confirmed that there has been a nuclear meltdown in the Fukushima nuclear plant. This was reported by ARD correspondent Hetkämper.

It now only readable at http://www.tagesschau.de/nachrichtenticker/ since the main article was updated to reflect the fact of a nuclear meltdown: "Explosion und Kernschmelze in AKW" (explosion and nuclear meltdown in nuclear plant), from before "Explosion in AKW - Kernschmelze befürchtet" (explosion in nuclear plant -- fear of nuclear meltdown) the breaking news box was removed form the top of the page accordingly.

See ARD (broadcaster). This is a reliable source. I am sure other sources will turn up, also English ones. --rtc (talk) 11:53, 12 March 2011 (UTC)

This would be as to say we have to remove japanese sources because you cannot read them. Please reinclude the meltdown happening. 92.194.3.196 (talk) 11:55, 12 March 2011 (UTC)


 * That would be a bad move. Wait until you have at least one good, reliable, English source, then the material can go back in. Until then, hold your horses. All of you. We do not need to blamed for an international panic from this nuclear incident. Wait and see is the best approach to be had here, and its also the one least likely to get users blocked (hint hint to all...) TomStar81 (Talk) 11:58, 12 March 2011 (UTC)
 * You won't be able to censor the information for very long anyway; international media are catching up quickly with the German ones just as we discuss. If the news will cause a panic, it won't be avoidable anymore, anyway if Wikipedia censors it. Poeple will read it on other websites. --rtc (talk) 12:04, 12 March 2011 (UTC)
 * I'm not moving that the info be censored, only that the it be sourced to an English source before it goes up here. This si going to be big news -obviously- so I feel its only right that we wait and site with English sources so folks will be able to read it in their native language. Be patient, if its true then your info should be validated soon, probably within the hour, and then we can in good faith put it up for all to read. TomStar81 (Talk) 12:07, 12 March 2011 (UTC)
 * The problem is not so much the requirement of a source in English that the requirement of several concurring sources. Robert Hetkämpfer is probably an excellent journalist, but he can have misunderstood something. I approve waiting something like an hour. If there is really something coming from the Japanese authorities, it will be on AP or Reuters or the BBC in less than thirty minutes from now. French Tourist (talk) 12:10, 12 March 2011 (UTC)

According to http://www.stern.de/panorama/-liveticker-nach-dem-erdbeben-in-japan-verwirrung-um-kernschmelze-1662763.html japanese authorities now disclaim that a nuclear meltdown took place. --rtc (talk) 13:11, 12 March 2011 (UTC)
 * There seem to be several official sources giving fundamentally conflicting information. See below. --rtc (talk) 13:26, 12 March 2011 (UTC)

New confirming meltdown??
http://translate.google.com/translate?js=n&prev=_t&hl=en&ie=UTF-8&layout=2&eotf=1&sl=auto&tl=en&u=http%3A%2F%2Fwww.n-tv.de%2Fpanorama%2FARD-Kernschmelze-bestaetigt-article2810866.html&act=url

Is this really happening? 149.6.120.130 (talk) 11:49, 12 March 2011 (UTC)
 * Its not confirming a meltdown, it is speculating that there may be a meltdown, and those are two radically different things. Until the national Japanese nuclear agencies issues an official release that there has been a meltdown all we have is speculation, and that fails WP:RS. As to whether the nuclear reactor is in trouble: that part is true, but at this point the disaster is shaping up more to the Three Mile Island incident than a Chernobyl Incident. TomStar81 (Talk) 11:55, 12 March 2011 (UTC)
 * No, it is clearly saying that japanese authorities have officially confirmed that there was a nuclear meltdown. --rtc (talk) 11:59, 12 March 2011 (UTC)
 * I just saw it on TV (on ABC News 24 that it's confirmed to be a meltdown, but nothing in writing that we can link to yet. Lets hold off until we have that.  Lankiveil (speak to me) 12:00, 12 March 2011 (UTC).
 * You should keep in mind, German media are clinging for a nuclear meltdown. Nuclear energy is a topic of big controversy in Germany, and most of the media are clearly left-wing. If you compare German TV and news papers with, say, CNN and BBC, you immediately notice they focus on the nuclear power plants, speculating whether there has been a nuclear disaster. -- Hence, I believe, German media are biased and not fully reliable. --131.220.99.58 (talk) 12:19, 12 March 2011 (UTC)
 * Can we please keep politics out of our fucking science and real life matters? Cheers. 149.6.120.130 (talk) 12:21, 12 March 2011 (UTC)
 * This British article seems to call meltdown 'unlikely' http://www.independent.co.uk/news/science/meltdown-unlikely-experts-on-explosion-at-japan-nuclear-plant-2240147.html Serazahr (talk) 12:23, 12 March 2011 (UTC)
 * There we go and update in English: http://www.staradvertiser.com/news/breaking/117843738.html Serazahr (talk) 12:26, 12 March 2011 (UTC)
 * Also just as a note: According to a Japanese speaking friend the minister was mistranslated to German (I know it's not a reliable source, but it helps shed some light) Serazahr (talk) 12:33, 12 March 2011 (UTC)
 * a high level crisis meeting with Chancellor Merkel, Berlin (GER) concludes: indiciations lead us to conclude, that there was a meltdown at F-1 plant. The German ISAR rescue mission aborts and is pulling out of Japan for fear of further nuclear catastrophe. TEPCO was at liberty to let off some steam.   --92.227.142.21 (talk) 17:05, 12 March 2011 (UTC)
 * Source? --joe deckertalk to me 18:33, 12 March 2011 (UTC)
 * source: Deutsche Welle radio, news today —Preceding unsigned comment added by 92.227.142.21 (talk) 19:00, 12 March 2011 (UTC)

Conflicting information on a meltdown
Ok, I'm getting conflicting reports on the matter now; the Japanese seem to be reporting that the situation is under control, the explosion was not a major incident, and that the radiation levels and the nuclear reactor pressure have gone down since the detonation. On the other hand, many news sources are speculating about a possible nuclear meltdown, and according to some sources the military and other experts are only now beginning to get to the site. I think for the time being being, taking all these aspects into account, some mention should be made concerning media speculation about a nuclear meltdown, while also noting what the Japanese govt is saying. TomStar81 (Talk) 12:36, 12 March 2011 (UTC)
 * The cause given by the Japanese government is still very fresh (<half hour I think). I am afraid that the news stations were getting a bit ahead of themselves following the explosion and didn't realize that also "conventional" equipment on site can fail... But, that's just my interpretation. If it stays like this, I think we should add it, but let's wait for 30 minutes to see if the major networks tone down after they could weigh the Japan governemnt info... How does that sound? L.tak (talk) 12:42, 12 March 2011 (UTC)
 * Not sure if we will wait, but let's give it a shot. --Kiz o r  12:44, 12 March 2011 (UTC)
 * "situation is under control, the explosion was not a major incident, and that the radiation levels and the nuclear reactor pressure have gone down since the detonation." is not neccessarily in conflict with a nuclear meltdown. If the melted nuclear matter is still inside the containment of the facility, these two claims are actually compatible with each other. Most people think about Chernobyl when they hear the term "nuclear meltdown". However, Chernobyl was much more than a nuclear meltdown; it was the complete destruction of the containment in addition to nuclear meltdown. Also, most people associate "nuclear meltdown" with the explosion that has happened. That is probably not correct. The explosion may well be completely unrelated to the core of the reactor, yet the core itself may be melting down, completely independent from the explosion. If any information is included in the article, this needs to be made clear. People just hear nuclear meltdown, and seeing the explosion, they start to think "Oh, it's like chernobyl." that misinterpretation needs to be avoided. --rtc (talk) 12:46, 12 March 2011 (UTC)


 * Per above, ARD now has this article as the lead on it's main page, with the first two lines reading "A meltdown has occurred in the damaged nuclear power plant in Fukushima. The National Agency for Nuclear Power Safety confirmed this according to information from ARD Correspondent Robert Hetkämper." ("In dem beschädigten Atomkraftwerk in Fukushima hat es eine Kernschmelze gegeben. Das bestätigte die Nationale Behörde für Kernkraftsicherheit nach Informationen von ARD-Korrespondent Robert Hetkämper in Tokio.") More evidence to suggest something's happened (although I am aware we can't use this site in the article because of the language). -- gtdp (T)/(C) 12:50, 12 March 2011 (UTC)
 * Please be careful with German sources. The Japanese ones - the reactor's operator and the Japanese government - are much closer and more likely to be accurate.  I think there may be a language problem with the German correspondent.  The Japanese mostly know english, and they're either broadcasting in Japanese (naturally) or english.  Georgewilliamherbert (talk) 13:04, 12 March 2011 (UTC)
 * You're right, it certainly does seem that this would have hit the other news agencies by now if there was any validity behind it, and it does look like somebody there mucked up a translation or something along those lines. The source was provided mainly for comparison with the original ARD source posted above: I certainly think this isn't verifiable when looked at in the context of other news reports (and is in the wrong language to be used in the article anyway). -- gtdp (T)/(C) 13:10, 12 March 2011 (UTC)


 * Forget the ARD. Yes, it's a major news source, but all they're doing right now is reporting hearsay. Rumours turn into "facts" due to the lack of actual information. The ARD is German, so am I. Their understanding of English sources is sometimes terrible, not to mention Japanese. Overall, their technical knowledge of the matter isn't that well, either. Journalists here usually study the German language and maybe history. We do have several elections comming up and the Green party is big on abolishing nuclear energy. Our TV coverage has been heavily influenced by that, and most experts cited are from anti-atomic-energy groups like Greenpeace, the Greens and others. During the last press conference the Japanese PM stated that as of back then, no meltdown has taken place to his knowledge. That's better than speculations of a German TV station, don't you think? --91.32.100.122 (talk) 13:13, 12 March 2011 (UTC)
 * The ARD's tagesschau that is currently on air says there are several official sources giving conflicting information on all kinds of aspects. Some seem to say officially that a meltdown is happending, others seem to officially deny this. Some say officially that radioactivity increased by 1000 times, others say officially radioactivity did not increase at all. So it's a very confusing situation with conflicting information. I don't think the ARD is biased because of political reasons. During the tagesschau there was an interview with a German minister from the pro-nuclear right wing government, who said that according to the information they have, a nuclear meltdown is currently happening, as a process, not as a rapid thing (ie, not an explosition or something). --rtc (talk) 13:22, 12 March 2011 (UTC)


 * I am aware of the opinion of the ARD held by a number of Germans, and the political situation regarding nuclear power in Germany, but that doesn't change the fact that the ARD generally is a national broadcaster which meets WP:SOURCES... although I should make clear again that I do not think these sources should be used in the article (for a number of reasons), and that the source was only provided as a follow on to the previous discussion related to the ARD - I'm happy to leave the discussion there as it's starting to get off-topic. -- gtdp (T)/(C) 13:21, 12 March 2011 (UTC)
 * I am not challenging the ARD as a source in general. I'm describing how they're currently acquiring their information and why this doesn't qualify them as a source for this article. Sure, they do have some correspondents in Tokyo, but frankly, I've seen more politicians and Greenpeace people talking on German TV than, let's say, the Japanese PM. Even their correspondents in Tokyo aren't native speakers. And the Japanese language is really hard to understand. Japan isn't North Korea, we do have enough Japanese sources that tell us what is currently considered to be factual. --91.32.100.122 (talk) 13:33, 12 March 2011 (UTC)
 * All this off-topic discussion doesn't help. Did you search for a Japanese source that confirms ARD's reports? --rtc (talk) 13:38, 12 March 2011 (UTC)
 * As stated above, I'm watching NHK. I've seen the press conference of the Japanese PM about an hour ago. The ARD doesn't magically know more than the Japanese Media they're citing. Can we agree on that? (Besides, this isn't offtopic).--91.32.100.122 (talk) 13:43, 12 March 2011 (UTC)
 * What is off-topic is the discussion of political bias of ARD and other sources. NPOV doesn't say a source may not be biased. It says that all relevant conflicting biased views have to be described, not merely one of them. The ARD is not citing Japanese media. It is citing various Japanese authorities, who seem to be giving conflicting information (which is admitted by the ARD). The ARD and a member of the pro-nuclear German government reported in its tagesschau that the Japanese PM seems to say there is no problem at all, no meltdown, no radioactivity leakage, no problem with the containment, but that, on the other hand, the Japanese nuclear authorities and the company that runs the power plant say a meltdown is in process. --rtc (talk) 13:49, 12 March 2011 (UTC)


 * tagesschau just showed video from the press conference where the English translator (as the tagesschau comment emphasized) spoke of a beginning nuclear meltdown. --rtc (talk) 13:55, 12 March 2011 (UTC)


 * http://www.tagesschau.de/ now changed its headline to "Widersprüchliche Angaben über Kernschmelze" -- conflicting information on meltdown --rtc (talk) 13:59, 12 March 2011 (UTC)


 * http://www.tagesschau.de/ausland/fukushima130.html (German) summarizes the various conflicting information. --rtc (talk) 14:06, 12 March 2011 (UTC)


 * Spiegel online reports (17:07 CET) that according to several reports from Japanese media, experts from Tepco and Nisa are on the plant site and found Cesium and Iodine. They concluded that there is a high probability for a meltdown. The wiki article still does not mention anything about the meltdown issue. --rtc (talk) 16:30, 12 March 2011 (UTC)

*A* confirmed leak
The article seems to say only that the vented deliberate radiation was leaked. Sky News UK live on air is reporting that per Japan officials there is a confirmed unintended "leak" of nuclear material. 149.6.120.130 (talk) 12:03, 12 March 2011 (UTC)
 * Let's wait for written sources on that. If you see them, please post them here... L.tak (talk) 12:22, 12 March 2011 (UTC)

Cause for explosion
"The explosion at Japan's Fukushima nuclear plant was not caused by the nuclear reactor but by "water vapor that was part of the cooling process," Chief Cabinet Secretary Yukio Edano said Saturday. He said no harmful gases had been emitted by the explosion." http://news.blogs.cnn.com/2011/03/12/japan-earthquake-live-blog-death-toll-rises-amid-widespread-destruction/?hpt=T1 Can somebody add this please. It seems reliable. — Preceding unsigned comment added by Serazahr (talk • contribs) 12:08, 12 March 2011 (UTC)


 * Additional Source about the explosion not being in the reactor http://mdn.mainichi.jp/mdnnews/news/20110312p2g00m0dm073000c.html Serazahr (talk) 12:14, 12 March 2011 (UTC)

Additional confirmation here: http://www.abc.net.au/news/stories/2011/03/12/3162554.htm?section=justin

"Tokyo Electric later confirmed the reactor's inner container sustained no damage in the explosion." ✅ I added a reference and text; feel free to suggest additions etc... L.tak (talk) 12:21, 12 March 2011 (UTC)
 * Rubbish, remove!! Tokyo Electric is a biased source. 149.6.120.130 (talk) 12:22, 12 March 2011 (UTC)
 * They are the officials and are rel. facual up till now. I will look back if clearly accredited them and not stated it too much as a fact though... L.tak (talk) 12:24, 12 March 2011 (UTC)
 * Just caught a NHK broadcast with the energy minister of Japan confirming that the explosion was in the outer building, and didn't rupture the inner container. Seems well enough sourced.  Georgewilliamherbert (talk) 12:27, 12 March 2011 (UTC)
 * +1 to adding the reference, its from Chief Cabinet Secretary Yukio Edano —Preceding unsigned comment added by 203.122.220.188 (talk) 12:25, 12 March 2011 (UTC)
 * Indeed, I checked again. the Chief is a source we should not ignore (but still stating it is him saying it, not a confirmed fact)... L.tak (talk) 12:28, 12 March 2011 (UTC)
 * Thank you. Just good given the stakes here to be on the up and up and not trust the operator directly. That would be like trusting British Petroleum as the US Gulf of Mexico was being raped in the initial days. 149.6.120.130 (talk) 12:29, 12 March 2011 (UTC)

On causation, also from the same article (http://www.abc.net.au/news/stories/2011/03/12/3162554.htm?section=justin)

"A nuclear industry official says he believes the blast was due to hydrogen igniting, and may not pose a further threat." "'It is obviously an hydrogen explosion... due to hydrogen igniting," Ian Hore-Lacy, communications director at the World Nuclear Association, a London-based industry body, said. If the hydrogen has ignited, then it is gone, it doesn't pose any further threat.'"

My comment: Perhaps due to an inability to operate/control hydrogen recombiners due to lack of control or electricity. See: http://www.nucleartourist.com/systems/rw.htm.

So, meltdown likely did not occur concurrent with the explosion (but could still happen later). Obviously this is a trade group source, but H2 gas is a well-known danger post nuclear accident. It may be neutral to write that "Experts suspect the explosion was due to hydrogen gas released during containment venting operations." 12:43, 12 March 2011 (UTC) 66.65.191.165 (talk)


 * If you have Hydrogen, than you have radioactivity, as I see it. --Chris.urs-o (talk) 12:46, 12 March 2011 (UTC)
 * Thanks for that info. It's just a single comment from an outsider (but an expert). If we have a second source stating this as likely we could put it up, but now it feels too much as speculation to me (and as to what hydrogen is linked to radiation: I am not an expert and have no idea).... L.tak (talk) 12:48, 12 March 2011 (UTC)
 * I am somewhat of an expert, and have reviewed the video and photos available. It's entirely consistent with a gas explosion in the outer building, between atmospheric oxygen and hydrogen vented from the inner containment dome.  There's some radiation venting - they're saying 1,015 usv/hr in the middle of the vent area - but unless you stand inside the building wreckage for a few hours you're fine.  Georgewilliamherbert (talk) 12:57, 12 March 2011 (UTC)

Understood. If you want to add the theory, the source below (the Reuters' article about the using sea water to cool the reactor) reiterates that H2 (in combination with the steam) was the cause of the explosion, citing Chief Cabinet Secretary Edano.

"Edano said due to the falling level of cooling water, hydrogen was generated and that leaked to the space between the building and the container and the explosion happened when the hydrogen mixed with oxygen there." (http://af.reuters.com/article/energyOilNews/idAFTKZ00680620110312)66.65.191.165 (talk) 12:59, 12 March 2011 (UTC)


 * ✅And I have added the info now with the Reuters source.. L.tak (talk) 13:13, 12 March 2011 (UTC)

cause was an earthquake http://www.tepco.co.jp/en/press/corp-com/release/11031223-e.html http://www.tepco.co.jp/en/press/corp-com/release/11031225-e.html Today at approximately 3:36PM, a big quake occurred and there was a big sound around the Unit 1 and white smoke. Our two employees and two subcontract workers working for the safety of the plant were injured and transported to the hospital. In addition, a vertical earthquake hit the site and big explosion has happened near the Unit 1 and smoke breaks out around 3:36PM. Our two employees and two cooperation workers who had been working for the foundation of safety are suffered and they are all sent to the hospital. —Preceding unsigned comment added by 203.122.220.188 (talk) 13:02, 12 March 2011 (UTC)

I read the above press release to say: In addition[: (1) ] a vertical earthquake hit the site and [(2)] big explosion has happened near the Unit 1 and [(3)] smoke breaks out around 3:36PM. That these three things happened, not that they are necessarily linked.66.65.191.165 (talk) 13:11, 12 March 2011 (UTC)

Hydrogen is generated by chemical reaction with the zircalloy fuel cladding. (See, for instance, http://www.arn.gov.ar/MenoriaT/Mt99/Pi-6-99.pdf). Since the containment was being pressurized during the event, there is a presumed breach of the reactor coolant pressure boundary (RCPB). With that breach, any generated hydrogen would be released to the general containment atmosphere. Note that not all plants have post-accident hydrogen recombiners. If Fukushima does have one, it appears there wasn't the time or capacity to address all hydrogen (my speculation). The plant is clearly far outside of its design basis envelope. On the assumption that they were venting an H2-rich atmosphere, then the venting of containment brings the potential for combustion,. If combustion occurred during venting, we can assume that gas treatment system used for venting containment is toast. Topamo (talk) 01:03, 13 March 2011 (UTC)

Meltdown or not, we can safely speculate that fuel cladding has been breached. That, together with the loss of RCPB, makes the containment the last fission product barrier protecting the public. As they flood the containment, there will be further venting of containment. And without the gas treatment system, Fukushima will be an very unpleasant place to be around. Topamo (talk) 01:03, 13 March 2011 (UTC)

Hydrogen is also kept on site for generator cooling and primary chemistry control. These sources are maintained exterior to the primary containment, and could result in a hydrogen explosion in the Turbine building, which is typically designed to withstand expansion pressures less than 100 psig.

[The Turbine building cannot withstand anything close to 100 psig, so I guess that 'less than 100 psig' is technically accurate, but misleading. The pictures that I saw seemed to be the reactor building structure with its siding now gone. That led me to conclude it wasn't the hydrogen for the generator or water chemistry that was our villain. ] Topamo (talk) 01:03, 13 March 2011 (UTC)

TEPCO planning to cool reactor with seawater
This seems to be taken from Reuters: http://www.forexyard.com/en/news/Japan-to-fill-leaking-nuke-reactor-with-sea-water-2011-03-12T123704Z Serazahr (talk) 12:46, 12 March 2011 (UTC)
 * and a better source: Reuters. Will add... L.tak (talk) 12:51, 12 March 2011 (UTC)

filling up the containment vessel with sea water for cooling is a high tech approach to things. It shows, that all the talk about the technological sophistication of nuclear technology is fully deserved. This technology was made possible by the invention of the bucket by Albert Einstein. --92.227.142.21 (talk) 19:07, 12 March 2011 (UTC)
 * well why do you think they build them by the sea?Sandpiper (talk) 20:45, 12 March 2011 (UTC)

Released 2011-03-13 (Sun) 0900 JST: Safety of Japanese Nuclear Reactor Secured after Blast: Regulators Cjs (talk) 02:25, 13 March 2011 (UTC)

Recentism
Folks, please write your propose in historical perspective. Active words like "are" and "is" are present tense and not appropriate for an encyclopedia unless in a quote. As_of says to use language that wont be dated quickly.--v/r - TP 13:16, 12 March 2011 (UTC)
 * Agreed. 220.100.15.15 (talk) 13:27, 12 March 2011 (UTC)
 * Also agreed, started removing some... L.tak (talk) 13:40, 12 March 2011 (UTC)

Look at the section heading...that is what the section is about, the current events...is/are will be adjusted as time elapses...it is a current situation, and isn't past tense.--MONGO 14:22, 12 March 2011 (UTC)
 * Wikipedia is not a news source, it's an encyclopedia. Wikinews will be in present tense.--v/r - TP 14:35, 12 March 2011 (UTC)

Edit request
One more expert saying that another Chernobyl is unlikely, citing the same reasons. http://news.sky.com/skynews/Home/World-News/Video-Fukushima-Nuclear-Fallout-How-Bad-Could-It-Get/Article/201103215950994?lpos=World_News_First_World_News_Article_Teaser_Region_4&lid=ARTICLE_15950994_Video%3A_Fukushima_Nuclear_Fallout%3A_How_Bad_Could_It_Get


 * Professor Robin Grimes, from the Centre for Nuclear Engineering, told Sky News that the Chernobyl plant was an old Russian design which had a completely different structure to Fukushima.
 * "The plants in Japan are light water reactors so they work on a very different principle," he said.
 * "The type of problems that one might anticipate will be quite different to Chernobyl."

220.100.15.15 (talk) 13:25, 12 March 2011 (UTC)
 * Now unprotected; you can make the change yourself. — G FOLEY   F OUR  — 15:15, 12 March 2011 (UTC)

Redundancy
The cause of the Explosion is written twice (first paragraph and last paragraph of 'explosion') Serazahr (talk) 14:21, 12 March 2011 (UTC)

Irradiation of evacuees
3 Evacuees where affected by the nuclear radiation Source:WallStreeJournal Serazahr (talk) 14:49, 12 March 2011 (UTC)
 * I myself can't access the original anymore, but I had it cached:
 * "TOKYO (Dow Jones)--3 people have affected by radiation from Tokyo Electric Power Co.'s (9501.TO) Fukushima Daiichi nuclear power plant, Japanese media reported Saturday.


 * However, Kyodo News cited Fukushima Prefecture as saying that because the radiation was detected on their clothes, there was no immediate need to decontaminate the three people who were evacuated from within a three mile radius around the plant. " Serazahr (talk) 15:02, 12 March 2011 (UTC)

Hydrogen explosion
"that the concrete outer structure had collapsed as a result of a hydrogen explosion triggered by falling water levels."This makes no sense when the reactor vessel is assumed to be whole a few sentences later. That would be so unlikely that a building of that magnitude is reduced while a steel reactor vessel asemble and penetrated a hundred times survives? Especially since it was the source of the exposion. No Way! Please omit speculation about the buildings status, since there is no image backing this up. Deepsean666 (talk) 19:08, 12 March 2011 (UTC)
 * The status came from a source, (reuters), but I have tried to explain their rationale a bit more in depth now. Is that better? L.tak (talk) 19:16, 12 March 2011 (UTC)
 * de.wikipedia cites japanese media that the uranium stabs are 4 m long and the water level was 1.7 m at the all time low (Spiegel online live ticker/Asahi newspaper). Because the cooling system was without electricity and the pressure was too high, they let vapor out to cool the reactor down. Chemical analysis found Cesium and Iodine, implying on some rod exposure to air and some melting, and breaking of water to a hydrogen/ oxygen mixture. --Chris.urs-o (talk) 19:53, 12 March 2011 (UTC)
 * Do these Japanese ref. help? and . Oda Mari (talk) 20:06, 12 March 2011 (UTC)

I dont know exactly how this reactor is constructed and I agree the article is confusing. The reactor itself will have a very strong steel shell and be contained inside a further probably airtight concrete building. The outer building has blown up because of gas vented from the inner vessel. The inner vessell would not necessarily be damaged by large quantities of concrete falling on it, it is designed to withstand this sort of thing, but I dont know how the various pipe connections are doing. The use of the word 'container' is confusing in the article. I know it is in the source, but that just means they dont know what they mean either. I suspect a translation issue.

They would have let gas out to reduce pressure. The water inside the reactor would have boiled because heat could not escape and the pressure had to be released because otherwise it would have exploded frm the pressure. Far worse of the reactor vessel blew up, though I expect it is designed to fail at designed weak point to minimise damage. Once pressure was released, then the core would be uncovered and I heard elsewhere, the fuel elements would then start a chemical reaction giving off hydrogen gas. This also had to be vented, but is explosive. Something ignited it. The concrete outer building was blown to pieces. This is quite serious. Anyway, someone needs to figure out a bit better the reactor design so it can be explained more clearly. Sandpiper (talk) 20:08, 12 March 2011 (UTC)
 * You see on the video that the explosion blew the outer shell away from the building. They are pumping see water now, they should have done that before red hot rods began to split up water into hydrogen and oxygen. --Chris.urs-o (talk) 20:12, 12 March 2011 (UTC)
 * But you would need pumps to pump. I am a bit concerned what is happening to reactors 2 and 3. Are they also short of cooling water, albeit no explosions yet? Sandpiper (talk) 20:49, 12 March 2011 (UTC)
 * Emergency pumps don t need electricity. Seems that 5 reactors are having difficulties with the cooling. --Chris.urs-o (talk) 21:09, 12 March 2011 (UTC)
 * Emergency cooling systemm pumps indeed need electricity, especially shortly following shutdown. Some reactor designs may allow passive cooling after much of the residual heat had decayed. —Preceding unsigned comment added by 91.127.190.232 (talk) 23:08, 12 March 2011 (UTC)
 * You do need electricity to control some functions. That was/is the main problem. No offsite power, failure of backup generators, only battery power left. --91.32.100.122 (talk) 22:09, 12 March 2011 (UTC)
 * The wiki article on these reactors safety measures talks about diesel driven pumps as well as backup generators, not that I know where that fact might fit in.Sandpiper (talk) 22:20, 12 March 2011 (UTC)
 * The diesel generators were taken out by the tsunami. Apparently, this particular setup included backup batteries, which lasted ten hours, and had a form of steam engine that could be used to drive the coolant pumps at a low power level as long as there was still steam in the system, which, last I knew, was the only source of cooling they had left.  rdfox 76 (talk) 00:25, 13 March 2011 (UTC)
 * The writeup of safety measures seems to suggest steam from the reactor is used to drive first stage emergency cooling, but if pressure is lost it then moves on to further measures. Sounded as though the last step might be gravity fed emergency cooling water. Sandpiper (talk) 01:01, 13 March 2011 (UTC)
 * My imperfect understanding is that there are no strictly passive systems on Fukushima-1 Unit-1. There is a steam driven system, I think, that does not need electricity. However the valves to deliver coolant do need electricity. The battery backup is not to drive the pumps but to supply DC electricity to operate the valves (they can be operated manually, but I think there have been some difficulties attempting manual operation) Newer designs (ABWRs, I believe) have passive systems in place should the active systems fail, but this old GE design does not. Again, this is only what I've picked up in the last day, I am not a nuclear engineer. --Zippy (talk) 05:34, 13 March 2011 (UTC)

"Fukushima nuclear disaster"
Someone created Fukushima nuclear disaster... it doesn't contain much information, much less than here. Should we redirect it here, or are we splitting off the earthquake section? So we would then redirect it to where it splits to... 184.144.160.156 (talk) 20:04, 12 March 2011 (UTC)
 * I redirected here for now - we can't have two ongoing articles about the same event. First we should get consensus here for a split and then do it properly.--Pontificalibus (talk) 20:08, 12 March 2011 (UTC)
 * I redirected to the article, but I agree we should wait to determine if a split is appropriate. VQuakr (talk) 20:09, 12 March 2011 (UTC)
 * Thanks, that's what I meant to do, instead of redirecting to this talk page! --Pontificalibus (talk) 20:12, 12 March 2011 (UTC)


 * There is also a possibility of making it a disambiguation page, since there are also the incidents at Fukushima II Nuclear Power Plant. 184.144.160.156 (talk) 20:13, 12 March 2011 (UTC)
 * Oops! I tagged the article for speedy delete. Oda Mari (talk) 20:16, 12 March 2011 (UTC)
 * So far no mass casualties, so "disaster" seems premature, and Wikipedia must not be sensationalistic compared to what terminology the mainstream news media are using for the event. Edison (talk) 20:36, 12 March 2011 (UTC)


 * I'd like to suggest we keep the information here. We have a well-written article and update, and splitting it off into a different article seems counter-productive. Agree that it is too early for the word "disaster" at this time.  Jus  da  fax   22:20, 12 March 2011 (UTC)

Tsunami
The article says the plant was hit by an earthquake. Was it also hit by a tsunami, which is implied later? Any clarity on damage caused by one or by the other? Sandpiper (talk) 20:30, 12 March 2011 (UTC)
 * de.wikipedia tells the emergency generators stopped producing electricity after the tsunami hit the coast. The timeline is not clear, agree with u. --Chris.urs-o (talk) 20:37, 12 March 2011 (UTC)
 * timeline, local time:
 * 14:46 11 March, earthquake
 * after one hour tsunami hits and emergency generators stop
 * generators are delivered but the connecting cable is the wrong one
 * 13:30 12 March, radioactive caesium was detected
 * 15:36 12 March, outer shell is blown away
 * Some details Here see NUCLEAR THREAT'section. ☢ - 220.101 User talk:220.101.28.25\ 20:46, 12 March 2011 (UTC)
 * It doesnt really explain what happened. An expert saying he thinks an explosion is unlikely. Got that wrong. Sandpiper (talk) 20:59, 12 March 2011 (UTC)

0.18 grams acceleration
This is clearly wrong, I dunno how to get the convert template to show g-force or other units (m/s^2, ft/s^2 ...) 129.97.246.125 (talk) 20:59, 12 March 2011 (UTC)


 * Forget the Convert template. It causes more problems than it solves in many cases.  1 g = 9.8 m/s2, so 0.18 g = 1.74  m/s2.  Dead simple. &mdash;QuicksilverT @ 21:10, 12 March 2011 (UTC)
 * And the most recent pending revision shows just that. Until a reviewer approves it, however, we'll not see that go live.  rdfox 76 (talk) 21:12, 12 March 2011 (UTC)

Scheduled shutdown date
The article currently says "scheduled for shutdown on March 26, 2011" however that appears to be a rough estimate based on 30 years of operation. The original source just says March 2011. Are there any other sources saying it was actually scheduled to be shut down before the disaster? - unsigned by 98.234.112.7 21:22, 12 March 2011
 * agree this is a bit worrying. We have a report that units 7 and 8 are delayed by a year. I wonder what that means for the schedule dates of taking things out of operation... L.tak (talk) 22:26, 12 March 2011 (UTC)
 * Uhm, while this is purely speculative, you can assume that I will be out of business for good. It was supposed to be taken off very soon. It's not reasonable under any circumstances to repair it. --91.32.100.122 (talk) 22:52, 12 March 2011 (UTC)


 * The source for the shut down date is here: http://www.icjt.org/npp/podrobnosti.php?drzava=14&lokacija=818


 * This should be added as a reference.


 * I had asked earlier (in the Discussion - Built vs. designed. vs. constructed section) if anyone know if the the scheduled shutdown date shown in this reference (26 Mar 11, only a couple weeks before the accident) is really an accurate "decommissioning" date? Each of the shutdown dates shown in the source are exactly 40 years after the commercial operation date. Do operational licenses run 40 years in Japan, with no extensions? But there was no response.


 * Obviously, Unit 1 isn't going to return to operation, however, if this is was an accurate shutdown date, it is worth noting.66.65.191.165 (talk) 23:41, 12 March 2011 (UTC)

According to http://www.msnbc.msn.com/id/42044156/ns/world_news-asiapacific/, "Japanese regulators decided in February to allow it to run another 10 years." 70.225.190.27 (talk) 05:59, 13 March 2011 (UTC)

BBC Live Blog as source
This should really be removed as any source of information in the article proper. The BBC is very specific about their live blogging events not being independently verified and should not be considered as fact, and often discusses speculation/conjecture.

If that blog is claiming a certain source gave a particular piece of information, then that needs to be what's sourced, not the blog. Moreover, the url is likely to change, and with no cache of a live blog there will be no way to later verify any information cited.

Basically, it needs to be removed. A live blog, even if from a reliable source, is not considered reliable as continuous content. Datheisen (talk) 21:23, 12 March 2011 (UTC)
 * Ok, but give one - three days until we have some good overviews/sources published. --Chris.urs-o (talk) 21:27, 12 March 2011 (UTC)
 * You mean we should continue to add information from unverified blog posts until better sources publish verified information? Sorry, but no. --Pontificalibus (talk) 21:54, 12 March 2011 (UTC)
 * I was only thinking about not to erase BBC live blog and Spiegel online live ticker, until we get tomorrow a better source. Nothing about adding more. --Chris.urs-o (talk) 21:59, 12 March 2011 (UTC)
 * If anything, the BBC are one of the more conservative news reporting network and only report fact if its verified as true. In other words they avoid "guesswork" like tabloids and other news networks who frequently use "sources" Stevo1000 (talk) 03:17, 13 March 2011 (UTC)
 * I agree those refs should go now. Unverifiable does not mean that those blog entries are not verified by the publisher, but that today readers cannot verify yesterday's posts because they are gone from the blog. In other words, for example, can you now find anywhere on a BBC-hosted website that "The explosion was officially confirmed at 18:43 JST (9:43 GMT)."? It's definitely not in this URL any more. 113.197.242.129 (talk) 05:50, 13 March 2011 (UTC)
 * The BBC has archived its live Japan updates. Those for Saturday (UTC) can be found here: http://news.bbc.co.uk/1/hi/programmes/9423417.stm . They reveal a surprising and somewhat disappointing dependence on AFP for information that could just as easily have been gathered directly from English-language Japanese sources such as Kyodo. —Preceding unsigned comment added by 82.132.248.86 (talk)

Basis of design
I have a question on this sentence: I like the expansion of the section a lot as it really finally describes the reactors well; but it is still a bit technical/unclear to a earthquake-layman like me. Hope I am not too cryptical! L.tak (talk) 21:54, 12 March 2011 (UTC)
 * Unit 1 was designed for a peak ground acceleration of 0.18 g (1.74 m/s2) and a response spectrum based on the 1952 Kern County earthquake.
 * When I think of a design basis I would think about equipment sizing based on required power production, not the safety structure design. How is that rephrasable. Does "The earthquake engineering design parameters were based on (..) for example makes sence?
 * What does "designed based on" mean? Should at least be able to withstand at least the 1952 earthquake? Or were the values of 0.18 g derived from a) the safety required, which was b) calibrated for this specific spot with as the input the response of the 1952 earthquake?
 * I have read the source now and propose:

Unit 1 was seismic design was based on a peak ground acceleration of 0.18 g (1.74 m/s2) and a response spectrum based on the 1952 Kern County earthquake. During the 1978 Miyagi earthquake all 6 units withstood a 30 s ground exceleration of 0.125 g (1.22 m/s2). </br but would appreciate a heads up from someone who has worked with these things before! L.tak (talk) 22:23, 12 March 2011 (UTC)

Boron and sea water
Anyone know why they are adding boron to the reactor? Having read the wiki article on safety measures (not that i understood it), it doesnt mention boron anywhere in the entire list of cast iron guaranteed worse case scenario fixes. Boron absorbs neutrons, and there arent supposed to be any because all the control rods will have been inserted automatically. The reactors would seem to be designed to be self sufficient in shutting down and maintaining cooling even in the case of power failure and damage. Reports from the company would seem to suggest that the several reactors at both power plants affected are in different conditions though it is hard to follow which stage of emergency shutdown they are at.

Similarly, what is the sea water for? It might be because the explosion has caused damage to the cooling water supplies for the damaged reactor. I am not clear if the seawater is being flushed through the reactor, or simply is running through a heat exchanger to cool the liquid contained in the reactor. This would perhaps make more sense. Sandpiper (talk) 22:17, 12 March 2011 (UTC)


 * Boron slows down the reactions. That's for later. For now, the seawater is to bathe the reactor vessel from the outside, to cool it down. AFAIK. -Colfer2 (talk) 22:48, 12 March 2011 (UTC)


 * It is into the core, not outside, according to the latest KEPCO press release: "We have been injecting sea water and boric acid which absorbs neutron into the reactor core." i.e. replacing the normal coolant flow it seems. I'd like to know what they are doing with the sea water outflow; into a pond, or out to sea contaminated? Rwendland (talk) 23:41, 12 March 2011 (UTC)


 * Water acts as a neutron moderator - promoting chain reaction. Boron is added to prevent this. Also it has been used to get Chernobyl disaster under control. Control rods being inserted do not mean much because core damage (meltdown) is dead cert already, even before an explosion, possibly immediately after cooling was lost in the wake of eartquake (hint: caesium detected outside the reactor, which can be released only when fuel is exposed to air). This whole story is heavily controlled and huge cover up of the scale of an incident is underway, so thinking about details of released information does not make much sense at this moment. —Preceding unsigned comment added by 91.127.190.232 (talk) 22:58, 12 March 2011 (UTC)
 * If you (or someone else) finds a reliable source citing that caesium is only released when fuel is exposed to air and referring to Fukushima, referring to the time when caesium was first detected, then this would make the article more accurate. -Mardus (talk) 00:25, 13 March 2011 (UTC)

With respect to Boron, that's a constituent of the Standby Liquid Control (SLC) System, which is a tank of borated (sodium pentaborate, or some similar chemical) water and pumps that get it to the core. Its design function is to mitigate an "Anticipated Transient without Scram", otherwise known as ATWS. It's an event where you want to insert your control rods (to stop the core's reaction) but, for some reason, the rods don't insert. The SLC injection serves as an alternate, if messier way to stop the reaction.

Since the major constituent of SLC is water, it becomes another source of water for the core if you really need it. The sodium pentaborate also has the secondary benefit of keeping radioactive iodine in solution, if you have failed fuel. That's beneficial for minimized dose release, as occurs when you vent containment. For that to be truly effective, however, you need to have pumps that can spray it into the containment atmosphere.Topamo (talk) 00:48, 13 March 2011 (UTC)

Page protection
Is there a protection mode that automatically accepts all edits from logged in users? I believe the current level of page protection is a turn off for editors and definitely a turn off for new users. I'd rather deal with the vandalism. So my suggestion is to: What is your opinion? Thanks! Daniel.Cardenas (talk) 23:35, 12 March 2011 (UTC)
 * 1) Remove page protection for logged in accounts
 * 2) If that can't happen then remove all page protection.
 * This is part of a test called wp:pending changes. In principle all autoconfirmed accounts (incl you) can edit automatically; however, if you edit after an IP made an edit, a reviewer has to accept the version of the IP first. The pending changes is very controversial and it is not yet clear if it wil be implemented fully. [I personally only today obtained the reviewer permission while struggling with the same problem...] Cheers! L.tak (talk) 23:39, 12 March 2011 (UTC)
 * I still feel this type of page protection does more harm than good. Daniel.Cardenas (talk) 01:40, 13 March 2011 (UTC)

Good update as of 2344 UTC, 12 March 2011
World Nuclear News has the best written, best informed news update I've seen in many hours: -- A. B. (talk • contribs) 00:19, 13 March 2011 (UTC)

Please do not state every single news source
It is not necessary to add the news source of every new information coming in, as long as the source is mentioned in the reference tag. It only dilutes the real information and makes the article harder to read.--spitzl (talk) 00:20, 13 March 2011 (UTC)
 * Agreed. At some point when things cool down we will also need to review all those timestamps, not sure how many of those will still be relevant from a historical perspective. 220.100.15.15 (talk) 00:42, 13 March 2011 (UTC)

Layman's terms
While there may be experts in the field that would understand ""100,000 counts per minute" (about 45 nCi)" or "385.5 microgray/hour (1 μGy = 1000 nGy) " many people cannot comprehend what those numbers mean, if they are bad, or good, or whatever. Maybe there can be a comparison between counts per minute and how many of those units people are generally allowed per minute/day/year when there isn't a nuclear disaster. i just feel that all those numbers to someone who has no idea what they mean, such as myself, might worry some people without something to compare it to. JBDRanger (talk) 00:42, 13 March 2011 (UTC)


 * I'm trying to fix the unit conversion but am continually reverted by Coffeepusher. Please comment on his talk page where the paragraph is reproduced! SamuelRiv (talk) 01:11, 13 March 2011 (UTC)


 * or we could talk on this page. Just a thought since that would let everyone have a say.  so here is what is on my talk page so far:

fyi: importance of this page: viewed 306K times on Saturday March 12th
http://stats.grok.se/en/201103/Fukushima%20I%20Nuclear%20Power%20Plant  Daniel.Cardenas (talk) 01:39, 13 March 2011 (UTC)

BBC Live Blog
I removed a reference to the BBC "live blog", since I think it's unverifiable. I notive 5 more references to it. Thoughts? 220.100.15.15 (talk) 02:47, 13 March 2011 (UTC)
 * BBC is always reliable —Preceding unsigned comment added by 24.18.132.80 (talk) 04:33, 13 March 2011 (UTC)
 * Unverifiable is different from unreliable. That link is unverifiable, because it is dynamically updated. 113.197.242.129 (talk) 05:25, 13 March 2011 (UTC)

Sea Water //
According to the last press conference, aired on NHK, sea water is not being used (and thus has likely not been used anyway), instead, they are using "normal" water. Could not find a written source about this new information yet. --91.32.119.142 (talk) 02:52, 13 March 2011 (UTC)
 * tepco website says " We started injection of sea water into the reactor core of Unit 1 at 8:20PM, Mar 12 and then boric acid subsequently." Sandpiper (talk) 03:22, 13 March 2011 (UTC)

News media overview links
I added these links that have a good overview of what is happening. What do you think? Thanks, Daniel.Cardenas (talk) 03:24, 13 March 2011 (UTC)
 * Overview from AlJazeera news - March 12
 * Explanation from ABC news and Physicist Dr. Michio Kaku - March 12
 * I think Dr kaku was enjoying himself greatly discussing worst case scenarios.Sandpiper (talk) 03:41, 13 March 2011 (UTC)
 * Are you suggesting that link be removed? Daniel.Cardenas (talk)

Kaku was sensationalizing. Conjuring visions of "China Syndrome" and "Chernobyl". He has no better information than we do. Filter out the wild speculations made by media "experts" who don't have any better than we do and Kaku's prognostications are revealed to have no particular evidential basis.

The reason I moved to WP as my news source for these kinds of events was specifically *because* of the way it filters the wild speculation. I do not favor including this Kaku link. Sbergman27 (talk) 04:32, 13 March 2011 (UTC)

Japan confirms meltdown
http://www.cnn.com/2011/WORLD/asiapcf/03/12/japan.quake/index.html?hpt=T1&iref=BN1 —Preceding unsigned comment added by 24.18.132.80 (talk) 04:31, 13 March 2011 (UTC)
 * That's NOT what the article says. Flatterworld (talk) 05:11, 13 March 2011 (UTC)
 * The article says authorities are assuming the possibility of a meltdown. (That said, in the cases prior where authorities have said "possible X" that seems to have been a soft way to introduce a later annoucement that "X has occurred". Obv. we can't use this kind of interpretation in the article, but I thought it would be useful context for the talk page.) --Zippy (talk) 05:41, 13 March 2011 (UTC)

File:2011-03-12 1800 NHK Sōgō channel news program screen shot.jpg
Someone uploaded a different file on top of this filename, from a different source. It is no longer the screenshot as indicated in the filename. This seems like a bad idea, since it is a different source, with a different image, and is unrelated to the original copyrighted source. 184.144.160.156 (talk) 05:20, 13 March 2011 (UTC)

Illogic
"NHK Sōgō channel TV screen shot of the Fukushima power plant before and after the explosion"

Someone explain to me how one image can capture two events in time? 98.176.12.43 (talk) 05:41, 13 March 2011 (UTC)
 * From the page on the image itself it looks like the caption is talking about a previous version of the image, which was a split-screen shot showing both before and after the explosion. I'd adjust the caption, but I can't figure out how to edit it. Wabbott9 (talk) 05:49, 13 March 2011 (UTC)
 * I suggest just reverting the file. The new image should be in a different filename. 184.144.160.156 (talk) 06:02, 13 March 2011 (UTC)

Secondary containment
According to the image supplied in the outside link http://allthingsnuclear.org/post/3824043948/update-on-fukushima-reactor the sentence "This building had not been designed as containment:..." is not correct. The outer walls have been designed to keep radiation inside, but not to withstand high pressures. Thfledrich (talk) 17:20, 13 March 2011 (UTC)