Japan Earthquake

Japan Earthquake | Page 906

Some of Kosako's papers:
T.Kosako， et al.， "Shielding benchmark experiment for spent fuel dry storage facility" Proc. of the 13-th Pacific Basn nuclear conference， p 200 (2002).
T.Kosako， "Safe management of spent radiation source" ***. Journal of Health Physics， Vol.38(2)， pp154-193 (2003).
T.Kosako etal.， "Consideartion on the critical group with respect to radioactive waste management" Nippon Genshiryoku Gakkai Wabun Ronbunnsyuu， Vol.1(4) pp449-461 (2002) in Japanese.
T.Kosako， "Clearance level discussion on solid radioactive waste" IRPA-10: Int. Congress of the Int. Radiation Protection Association， P-9-107 (2000).
by Rob in SF 4/30/2011 10:41:31 AM

I would assume Kosako-san has an asst. screen his emails, so any approach had best be compelling...
by Rob in SF 4/30/2011 10:49:01 AM

Good morning folks. I found this on Physics Forum this morning:

www.forbes.com

"In a tearful news conference, Kosako said he could not stay and allow the government to set what he called improper radiation limits of 20 millisieverts an hour for elementary schools in areas near the plant."

I saw the bit about tearful news conference yesterday but didn't know what the issues were, just that he was disappointed.

If you're looking for a hook, "doing it for the children" might be the way in.
by General Armchair 4/30/2011 11:00:17 AM

BTW, not sure where the 20 mSv/hr figure comes from, I think the kids are supposed to be redlined at something like 8 microSv/hr while in school (?), but supposedly that's to keep kids exposure to 20 mSv/year.
by General Armchair 4/30/2011 11:02:35 AM

@General Armchair 20 mSv/hr seems awfully high. In 13 hours they'd reach the (annual?, lifetime?) limit for a worker at the plant.

[I wuzz just figuring out so, too, in my mental math ... How can they finish the school term (I thought to myself)? - Alblee]
by Rob in SF edited by alblee 4/30/2011 11:07:50 AM

@Rob in SF Agreed. Though it would hardly be the first time millis and micros have been exchanged during this whole affair.

[Thanks, @General_Armchair, but in those areas around Ground Zero, I'm not sure there's any micro readings anymore... - Alblee]
by General Armchair edited by alblee 4/30/2011 11:08:55 AM

I noticed this morning that Fairewinds no longer has the April 26 Prompt-Criticality Cause of #3 explosion up on the initial page, though it can still be found on the site. Instead the April 21 discussion with Stephen Wing is on the home page. Hmmmm.

I'd gone on Fairewinds this morning because of another link found on PhysicsForum:

fairewinds.com

I hadn't seen this before, but assume it has been seen before on here? I was interested in a pic toward the end of the slideshow, that shows a BWR SPF with gate open to reactor well -- had not seen that pic before.
by General Armchair 4/30/2011 11:10:39 AM

@elainekirk I left Linh a comment as well and gave him this link as another option. I fear if he hit the other page at the wrong moment he might be perplexed...
by Rob in SF 4/30/2011 11:16:41 AM

That pic on Fairewinds of SPF with gate open and fuel assembly moving does seem to answer one of my questions yesterday -- do they move the assemblies through gate vertically? I would say based on this pic that probably yes, vertically. Perhaps there is still enough water above ONE assembly at that height to cut the radiation sufficiently, but to cut radiation from the whole load of fuel, they need the extra 4 meters or so of water?
by General Armchair 4/30/2011 11:18:12 AM

@Albee "The dose limit of the permissible effective dose from occupational radiation exposure is 20 mSv per calendar year in all European countries (in the USA 50 mSv/year)."

So school kids in Fukushima prefecture are now legally allowed to receive the kinds of doses that European nuke workers are legally permitted. The maximum hourly rate permitted actually works out to over 30 mSv/year, but was supposedly set to keep kids' exposures under 20 mSv/year, I guess under the assumption that time spent indoors will give them less exposure than being outside, etc.

I can certainly unders
by General Armchair 4/30/2011 11:32:46 AM

Ooops, forgot link to immediately preceding comment: www.bfs.de
by General Armchair 4/30/2011 11:33:22 AM

@General Armchair Interesting image indeed. That is an entire assembly being moved, and it appears there is 4 meters of water above it still. There is a safety margin of course, and when they drop the assembly in the SFP rack there will be far more water above it, no?

Amazing how big the equipment hatch through the containment wall is.
by Rob in SF 4/30/2011 11:34:54 AM

search.japantimes.co.jp

Saturday, April 30, 2011

Tepco pair caught radiation overdose
250 millisievert yearly threshold almost topped
Kyodo
Tokyo Electric Power Co. said Saturday one of its employees was exposed to radiation close to the legal yearly limit of 250 millisieverts at the crisis-hit Fukushima No. 1 nuclear plant and another worker's exposure was just under that threshold.

The two are the workers who were hospitalized for possible radiation burns to their feet March 24 after standing in water that contained radioactive materials 10,000 times the normal level while laying a cable underground at the plant, which was crippled by the March 11 mega-quake and tsunami... ... ...
by ALBLEE 4/30/2011 11:34:57 AM

the end of conformity ?

Kan comments on nuclear advisor's resignation

One of the nuclear advisors to Prime Minister Naoto Kan has resigned to protest what he called the government's impromptu handling of the nuclear crisis.

University of Tokyo Professor Toshiso Kosako, who tendered his resignation on Friday, also said that the government has belittled the law.

Speaking at a Lower House committee meeting on Saturday, Kan said Professor Kosako resigned because of disagreements with other scientists.

Kan said the government responded to the nuclear accident based on advice from the Nuclear Safety Commission and has never taken ad hoc measures.

Kosako also criticized the education ministry for allowing students at primary schools in Fukushima Prefecture to perform outdoor activities if the level of radiation of the school ground does not exceed 20 millisieverts per year.

The nuclear scientist said it's very unlikely that even workers at nuclear reactors could be exposed to such a high level of radiation, and therefore he cannot agree on that figure as an upper limit for children.

Chief Cabinet Secretary Yukio Edano told reporters that the ministry's decision seeks to reduce exposure to radiation and that it does not mean the government will allow the limit of 20 millisieverts per year for children.

Saturday, April 30, 2011 15:10 +0900 (JST)
www3.nhk.or.jp
by Edano 4/30/2011 11:40:26 AM

@Albee Originally TEPCO claimed exposures were in the 170 mSv range for the "bootless workers." Now up to 240. Check back next month for continued revisions?

Not sure what to say about one worker being exposed to radiation "close to the legal yearly limit" while the other's exposure was "just under that threshold." Sounds like a distinction without a difference: your guess is as good as mine whether you'd want to be exposed to levels "close to the legal limit" or "just under that threshold."
by General Armchair 4/30/2011 11:41:51 AM

search.japantimes.co.jp

Hmmm ... Possibly has to do with the IAEA mission this May?

Saturday, April 30, 2011
Panel to probe nuke accident
Kyodo
Prime Minister Naoto Kan will launch an independent panel around mid-May to investigate the causes of the accident at the Fukushima No. 1 nuclear plant.
"By sharing the lessons from the accident with the international community through the International Atomic Energy Agency and other channels, we will take the lead in contributing to safety improvements of nuclear plants around the world," Kan told a Thursday plenary session of the House of Representatives.
by ALBLEE edited by alblee 4/30/2011 11:42:52 AM

fwiw -- via TEPCO press release …
www.tepco.co.jp

"..., we have implemented the
determination of exposure dose by measuring internal exposure of workers
with high external exposure dose….

1.Number of workers subject to the measurement
21 (workers with more than 100 mSv of external exposure dose during the
emergency work at the end of March)

2.Result of measurement (total exposure dose from external and internal
exposure and number of workers)
200-250 mSv: 2
150-200 mSv: 8
100-150 mSv: 11

3.Maximum exposure dose
External exposure dose: 201.80 mSv
Internal exposure dose: 39 mSv
Effective exposure dose: 240.80 mSv(total dose from external and
internal exposure)
by Deirdre 4/30/2011 11:43:41 AM

@Edano As your namesake says in NHK story you posted, allowing kids to be exposed at dose rates up to 20 mSv/year does not mean they will alllow kids to be exposed at dose rates up to 20 mSv/year. (head spinning and eyes going googly) Wha'???
by General Armchair 4/30/2011 11:46:38 AM

Interesting, moderators can archive this entire blog as an Excel spreadsheet, but for: Max Number of Items (max 100,000 items will be returned, use date ranges to split large events)
by Rob in SF 4/30/2011 11:48:54 AM

@General Armchair : "there are no leaks in the leaking pool."
by Edano 4/30/2011 11:51:07 AM

"limit of 20 millisieverts per year for children."

This makes far more sense than 20 mSv/hr I must say...
by Rob in SF 4/30/2011 11:52:58 AM

General Question: How do they measure or determine your "internal dose"? Is there any way to determine internal exposure to alpha emitters like plutonium?
by General Armchair 4/30/2011 11:54:41 AM

@Rob in SF The 20 mSv/hour figure in the Forbes story was obviously mangled somehow, most likely by the reporter.
by General Armchair 4/30/2011 11:56:12 AM

@General Armchair they do bioassay testing on bodily fluids.
by Canadian 4/30/2011 11:58:10 AM

@General Armchair
It's greek to me: en.wikipedia.org

Re: Forbes, lotta Sv errors out there...
by Rob in SF 4/30/2011 11:58:28 AM

www.spiegel.de Tears of rage translate.googleusercontent.com
by Edano via Spiegel.de 4/30/2011 11:59:53 AM

@General Armchair here is a link about internal measuring: www.remm.nlm.gov
by Canadian 4/30/2011 11:59:57 AM

@Edano Yeah, saw a few of these shots of him so upset. He makes me very sad.
by Rob in SF 4/30/2011 12:00:56 PM

@Rob in SF : a nuclear scientist with compassion - hard to find.
by Edano 4/30/2011 12:02:46 PM

'Germany Is on the Right Track'
A Republican Environmentalist Finds Green Nirvana
www.spiegel.de
by Edano 4/30/2011 12:05:11 PM

Switching to Renewables
Germany Explores Using Train Lines as a Power Grid
Germany's increased emphasis on renewable energies requires an all-new power grid. Now, many in Berlin are wondering if the grid powering the country's train system could be used to transport wind power from the north to the south. Some say it could save up to 75 percent of expected costs. www.spiegel.de
by Edano 4/30/2011 12:06:37 PM

@Edano He's the head of the Nuclear Engineering Dept. at Tokyo University, the lab is named after him. We've been wanting to get him over here to chat...

Toshizo Kosako.
kosako＠nuclear.jp
Here's his faculty page:
www.t.u-tokyo.ac.jp
by Rob in SF 4/30/2011 12:09:02 PM

@Rob in SF : wow, cool ! now that he has resigned ......
by Edano 4/30/2011 12:10:07 PM

@Edano Yeah, this is the perfect place for him to leak the truth!
by Rob in SF 4/30/2011 12:11:01 PM

now, this is interesting:
Atomic Deserts
A Survey of the World's Radioactive No-Go Zones
www.spiegel.de
by Edano 4/30/2011 12:11:21 PM

Here goes, so sorry if redundant...
www.tepco.co.jp
Survey map of Fukushima Daiichi Nuclear Power Station(on April,27)
by ALBLEE 4/30/2011 12:13:10 PM

@Canadian or anybody: When TEPCO says (in Dierdre's link below) that:

"3.Maximum exposure dose
External exposure dose: 201.80 mSv
Internal exposure dose: 39 mSv
Effective exposure dose: 240.80 mSv(total dose from external and
internal exposure)"

does this mean the 39 mSv internal dose is to date (to the point where they took the readings and estimated the internal dose)? Or does it mean the expected LIFETIME dose from that internal contamination, taking into account factors such as half-lives of isotopes involved, how fast and whether they get flushed from the body, etc.?
by General Armchair 4/30/2011 12:14:25 PM

by Rob in SF via Disinfo-drop.s3.amazonaws 4/30/2011 12:16:30 PM

@General Armchair I am not totally sure how they are coming to the internal dose but it would be for the monitoring period. I don't know if there is a way to test or if they do a calcultion to get the internal. Either way it sounds extremely bad to get that kind of internal dose. I wonder if the internal dose is the person with the nasty radiation burn on their arm everyone wondered about?
by Nancy 4/30/2011 12:17:22 PM

@Nancy The article said the two with the close to 250 mSv dose were the two workers who stepped in the puddle in turbine building basement without boots on about a month ago or so.
by General Armchair 4/30/2011 12:18:29 PM

In this article it says they were exposed to between 2 and 6 sieverts. (about paragraph 14). www.nytimes.com
by Scilla 4/30/2011 12:27:26 PM

ress Releases
Press Release (Apr 30,2011)
Result of the exposure dose measurement during the emergency work at Fukushima Daiichi Nuclear Power Station

In order to prevent the situation that exposure dose of each worker
exceeds the statutory exposure dose limits*1 during the emergency work at
Fukushima Daiichi Nuclear Power Station, we have implemented the
determination of exposure dose*2 by measuring internal exposure of workers
with high external exposure dose.
We hereby disclose the result of measurement as the determination of
exposure dose for the workers with more than 100 mSv of external exposure
dose at the end of March completed.

1.Number of workers subject to the measurement
21 (workers with more than 100 mSv of external exposure dose during the
emergency work at the end of March)

2.Result of measurement (total exposure dose from external and internal
exposure and number of workers)
200-250 mSv: 2
150-200 mSv: 8
100-150 mSv: 11

3.Maximum exposure dose
External exposure dose: 201.80 mSv
Internal exposure dose: 39 mSv
Effective exposure dose: 240.80 mSv(total dose from external and
internal exposure)

*1: exposure dose limit
The exposure dose limit for the emergency situation in the emergency
response measures implementation area from the day of declaration of
a nuclear emergency situation until the day of cancellation of such
declaration is stipulated to be 250 mSv.

*2: determination of exposure dose
Determining the exposure dose by adding exposure dose during the stay in
Main Anti-Earthquake Building to the exposure dose during the work and
evaluating the committed effective dose of internal exposure.
www.jpubb.com
by elainekirk 4/30/2011 12:27:28 PM

@General Armchair @Nancy dean has talked a lot about how the body flushes certain isotopes. It seems mSv's of what isotope matters?
by Rob in SF 4/30/2011 12:27:48 PM

@Rob in SF I would assume/guess (though it IS TEPCO after all...) that in figuring internal does they would take those factors into consideration? Obviously measuring internal dose is just a tad like trying to figure out what is happening inside a reactor core by looking at what comes out, so it's going to be imprecise, which is why I assume the workers' external dose seems to have more precision than their internal dose (as reported by TEPCO).
by General Armchair 4/30/2011 12:31:56 PM

@Scilla I think they're saying the water itself was 2-6 sieverts, "It said that the amount of radiation the workers were thought to have been exposed to in the water was two to six sieverts."

Otherwise...
1 – 3 Sv (1000 – 3000 mSv): Mild to severe nausea, loss of appetite, infection; more severe bone marrow, lymph node, spleen damage; recovery probable, not assured.
3 – 6 Sv (3000 – 6000 mSv): Severe nausea, loss of appetite; hemorrhaging, infection, diarrhea, peeling of skin, sterility; death if untreated.
by Rob in SF 4/30/2011 12:32:41 PM