Read a little. Learn a lot. • Tightly-written news, views and stuff • Follow us on TwitterBe a Facebook FanTumble us!

15 Mar 2011 10:56

tags

World: Tracking radiation levels in Tokyo: A minorly scary photo

  • Photo of the day: “A radiation detector marks 0.6 micro-sieverts, exceeding normal levels Tuesday, near Shibuya train station in Tokyo. Concern over possible radiation exposure has increased after a fourth reactor released radiation, Tuesday.” To compare – this level is higher than average, but only a tiny percentage of what’s happening at the plant. 1,000 micro-sieverts per hour equals one milli-sievert per hour. So this is high, but still minor. (Kyodo News/AP) source

15 Mar 2011 10:28

tags

World: UPDATE: Fukushima’s radiation levels drop significantly

  • 11.9 the current peak radiation count, in milli-sieverts per hour
  • 400 the peak radiation count in milli-sieverts per hour – which was hit last night
  • 300k the peak mSv/hour count at Chernobyl – to keep things in check source
  • » It’s no longer at its peak, and that’s a good thing: The International Atomic Energy Agency says that the decrease happened over a six-hour period. And the IAEA makes a good point that you should keep in mind. “This is a high dose-level value, but it is a local value at a single location and at a certain point in time,” they say. In other words, even if you’re within the 20-mile radius where radiation is likely to hit, the level will most assuredly be far lower than these peak levels. It’s still high, though – one milli-sievert per hour is equal to the yearly legal limit of radiation you’re supposed to get. (see our earlier posts about this topic here and here)

14 Mar 2011 23:40

tags

World: UPDATE: What does “400 times annual legal limit” mean?

  • 400 the amount of radiation in the air, in milli-sieverts per hour, according to the given estimate
  • 40 the amount of radiation that is, in roentgen per hour – which, don’t get us wrong, is very high
  • 30k the amount of radiation in Chernnobyl had – which Fukushima doesn’t touch source
  • » This is an extremely large jump: One milli-sievert per hour is the legal annual limit for radiation in a year. Our earlier estimate showed a level of 8,217 micro-sieverts. 1,000 micro-sieverts equals 1 milli-sievert. So we went from 8,000 to 400,000 in a couple of hours. This is still no Chernobyl, but this is a huge jump. If it jumps to 1,000,000 micro-sieverts, it leads to radiation sickness – and then we’re in trouble.

14 Mar 2011 21:13

tags

World: Some quick math: How does Fukushima compare to Chernobyl?

  • » To explain: This number comparison is to emphasize the difference between an actual going-to-kill-us-all meltdown and what’s happening in Fukushima. While things could get worse from here, right now, the worst of what’s happening in Fukushima is 0.002739 percent as bad as the worst of the Chernobyl disaster. 400 rontgen is enough radiation to kill you. 10,000 micro-sievert equals 1 rontgen. Chernobyl was pushing out 30,000 rontgen per hour at its core – enough to kill someone in 48 seconds. This is an important point to make – while levels are higher than normal, this is extremely minor on the scale of a real disaster. Oh, and one more thing – Fukushima only hit its 8,217 micro-sievert peak for a very short period. Chernobyl’s level was sustained.

14 Mar 2011 11:07

tags

World: U.S. Navy: Officers helping in Japan exposed to radiation

  • 17 U.S. Navy personnel treated for low levels of radiation source
  • » But how … ? Apparently the officials were in Navy helicopters and flew through a plume of radioactive material let into the atmosphere by the Fukushima reactors. Yikes.

14 Mar 2011 10:48

tags

World: Fukushima evacuees: Reactor trouble completely unexpected

  • It said we had to go to the town hall to evacuate because there was trouble at reactor No. 1. I left with just my purse and the clothes I was wearing.
  • Fukushima nuclear plant employee Yoshiko Watanabe • Describing what happened when she found out the plant was first having trouble on Saturday. Since then, she and others have been sleeping on the floor at a school in the city of Iwaki.  She and other residents of Narahama are among the 200,000 people who have been forced from their homes by the situation at Fukushima. The town had no plan for anything like this and was caught off-guard. That’s because the reactor was made to withstand a quake, but not a tsunami. source

13 Mar 2011 18:37

tags

World: Quick rundown: What happened at Fukushima’s Unit 1 reactor?

  • 1st Normal cooling measures failed at Fukushima’s Unit 1 reactor, so officials resorted to using seawater to cool the reactor vessel.
  • 2nd Pressure rose within the vessel, so operators released steam from the reactor in order to prevent an explosion.
  • 3rd Due to rising temperatures, the fuel rod casings reacted with the seawater, creating zirconium oxide and hydrogen.
  • 4th The hydrogen-rich steam then reacted with oxygen in the environment, which then caused a hydrogen explosion. source
  • » So, where are we at now? First of all, it’s important to note that this is only one of six reactors in Japan currently placed under states of emergency. That being said: operators at Fukushima’s unit 1 reactor are still frantically trying to cool the unit. The fuel rod casings and the seawater reacted with one another when the temperature reached around 2,200 degrees Fahrenheit; things could get really bad if and when the temperature hits 4,000 degrees. This would cause the uranium fuel pellets to melt, at which point they’d eat through the floor of the reactor vessel, then that of the building, and begin to escape into the environment. At the same time, the walls of the reactor vessel would melt into a “lava-like pile,” react with the remaining seawater, and cause an explosion bigger than the one that already occurred. This explosion would spread the radiation around the environment, and…well, yeah. That would be very bad. We’ll keep you posted as more developments come out.
 

13 Mar 2011 11:53

tags

World: Laymen’s terms: Fukushima withstood the quake, not the tsunami

  • Reactors have been designed with such [earthquake] concerns in mind, but preliminary assessments of the Fukushima Daiichi accidents suggested that too little attention was paid to the threat of tsunami. It appeared that the reactors withstood the powerful earthquake, but the ocean waves damaged generators and backup systems, harming the ability to cool the reactors.
  • A piece from the New York Times • Explaining what appears to have happened, calmly and simply, with the current nuclear crisis. Overall, the effect is that Japan’s precautionary methods for nuclear plants were successful in what they were designed to do. The problem is, the design of the Fukushima Daiichi nuclear plant didn’t anticipate something far different. Which is why the current situation has escalated. source

12 Mar 2011 22:19

tags

World: Fukushima meltdown: Low level radiation leaks, iodine distributed to locals

  • All right, everyone, here’s where we’re at. Radiation has leaked from the Fukushima nuclear power plant in Japan. This is bad. However, it’s apparently not as bad as it could be, because the reactor core container itself wasn’t damaged. Furthermore, the mist hovering above the plant implies that radiation levels are low-ish. Officials are ranking it as less serious than both the Three Mile Island meltdown and the Chernobyl disaster. Nuclear meltdowns are ranked on a scale of 1-7; Three Mile Island was a 5, Chernobyl was a 7, and this one is currently being pegged as a 4. However, they’re nevertheless distributing iodine to the locals, which helps prevent the thyroid cancer that can result from radiation exposure. We’ll keep you posted as more news comes. source

12 Mar 2011 18:37

tags

U.S.: Fukushima: Dozens of people could’ve been exposed to radiation

  • 160 people are at risk of radiation according to the Japan Nuclear and Industrial Safety Agency
  • nine people have shown signs of radiation so far, based on early tests by multiple authorities source