Japan, Nuclear Meltdown - Page 3 - PeachParts Mercedes-Benz Forum

whunter · #31 03-21-2011, 11:12 PM

http://dailyplanetdispatch.com/new-radiation-alert-at-fukushima-levels-soar-to-1600-times-normal/856984/

#32 03-22-2011, 07:24 PM

Quote:

Originally Posted by whunter

http://dailyplanetdispatch.com/new-radiation-alert-at-fukushima-levels-soar-to-1600-times-normal/856984/

While these levels of exposure are not good, let me give you some perspective. The measured values of 161 microsievert per hour converts to 16.1 mrem (0.016 rem) per hour. The average dose received by everyone, due to natural/industrial/medical exposure, is about 360 mrem (0.360 rem) per year or about 1 mrem per day. The legal limit for radiation workers in the US is 5000 mrem (5 rem) per year. A lethal acute radiation dose (LD 50/60) is about 400,000 mrem (400 rem).

The bottom line is that I could spend about two full weeks being constantly exposed to the maximum reported dose rate (161 microsievert per hour) without even exceeding my legal annual limit. I'm not saying it's harmless, research indicates that 1000 mrem (1 rem) of exposure increases the instance of fatal cancer by about 0.0004 (about 4/10,000); compared to about 0.2 (2000/10,000) of the general population expected to die from natural instances of cancer. There is a finite risk and exposure should be minimized, but the media really needs to do a better job of explaining these numbers.

SwampYankee · #33 03-22-2011, 07:49 PM

Quote:

Originally Posted by Craig

but the media really needs to do a better job of explaining these numbers.

The odds of that are worse than the ones you stated.

Thanks for bringing some perspective to it!

whunter · #34 03-23-2011, 12:24 AM

http://www.japantoday.com/category/national/view/work-continues-to-restore-nuclear-plant-functions

whunter · #35 03-23-2011, 12:28 AM

Quote:

Originally Posted by Craig

While these levels of exposure are not good, let me give you some perspective. The measured values of 161 microsievert per hour converts to 16.1 mrem (0.016 rem) per hour. The average dose received by everyone, due to natural/industrial/medical exposure, is about 360 mrem (0.360 rem) per year or about 1 mrem per day. The legal limit for radiation workers in the US is 5000 mrem (5 rem) per year. A lethal acute radiation dose (LD 50/60) is about 400,000 mrem (400 rem).

The bottom line is that I could spend about two full weeks being constantly exposed to the maximum reported dose rate (161 microsievert per hour) without even exceeding my legal annual limit. I'm not saying it's harmless, research indicates that 1000 mrem (1 rem) of exposure increases the instance of fatal cancer by about 0.0004 (about 4/10,000); compared to about 0.2 (2000/10,000) of the general population expected to die from natural instances of cancer. There is a finite risk and exposure should be minimized, but the media really needs to do a better job of explaining these numbers.

The media seems to regularly mix up microsievert and millisieverts per hour.
The difference is x1000.........

chilcutt · #36 03-23-2011, 12:45 AM

The latest report I saw, was that power has been attatched to all 3 of the power plants, and after some more testing they can restore power.

In that event, what happens next?

Rahulio1989300E · #37 03-23-2011, 01:23 AM

Well since power is connected, my guess is that they need to now verify the wiring and piping of the cooling system. If they can confirm that the cooling system is ready to be restarted, then they need to fill the pools and vessels back up with water and start pumping... ???

A few sources have said that since they used sea water as a stop gap for cooling, the reactors/pools are now ruined. I have no idea if several days of exposure to salt water will ruin the reactors/pools/piping.

What is worrying is that at least one of the reactor's spent fuel pools is wide open and exposed to the outside. Like a bird can literally fly in and drink water from the pool... lol, not wise for the bird. So I imagine they would want to rebuild a room over that.

Another thing is that it has been more or less confirmed that some of the fuel rods in the reactors have partially melted. I imagine that will be near impossible to remove them from the reactor.

I think reactors 5 & 6 are fine and will probably continue to operate, pending the whole sea water usage thing.

I would imagine, that 1-4 will eventually be cleaned up to be best ability, then encased in a concrete tomb. (Or sarcophagus...

)

JohnM. · #38 03-23-2011, 05:39 AM

http://english.kyodonews.jp/news/2011/03/80462.html

Quote:

The Tokyo metropolitan government warned Wednesday that infants should not drink tap water as radioactive iodine exceeding the limit for them was detected in water at a purification plant.

The advisory covers Tokyo's 23 wards and five cities -- Musashino, Mitaka, Machida, Tama and Inagi.

According to the metropolitan government, 210 becquerels of radioactive iodine were detected per 1 kilogram of water against the limit of 100 becquerels in a survey Tuesday at a water purification plant in the Kanamachi district of Katsushika Ward.

But the amount of the radioactive substance detected at the purification plant is lower than the 300-becquerel limit for people other than infants.

mak · #39 03-23-2011, 05:53 AM

We wish them a quick recovery back to normal life .
A great nation with History,culture and the excellence of products.

#40 03-24-2011, 06:50 PM

The latest IAEA update:

http://www.iaea.org/newscenter/news/tsunamiupdate01.html

pj67coll · #41 03-24-2011, 07:05 PM

Quote:

Originally Posted by Craig

The latest IAEA update:

http://www.iaea.org/newscenter/news/tsunamiupdate01.html

Craig. What the heck is a sievert and where did it come from? I've only ever heard of radiation being measured in rems.

- Peter.

retmil46 · #42 03-24-2011, 07:20 PM

Quote:

Originally Posted by pj67coll

Craig. What the heck is a sievert and where did it come from? I've only ever heard of radiation being measured in rems.

- Peter.

IAEA unit of measurement. If I remember the conversion correctly, 1 sievert equals 100 rem. Don't feel like the lone ranger, this hoorah in Japan is the first I've heard of this unit of measurement as well.