Explosive concentrations of gas at Fukushima Unit 1? Hydrogen and Krypton-85 levels fluctuating since April, says Tepco

Published: October 26th, 2012 at 11:57 pm ET


Title: Status of TEPCO’s Nuclear Power Stations after the Tohoku-Chihou-Taiheiyou-Oki Earthquake (Daily Report as of 3:00 PM, October 23)
Source: TEPCO : Press Release
Date: Oct 23, 2012
Emphasis Added

At 9:37 AM on October 23, continuous nitrogen injection into Unit 1 suppression chamber was started. The nitrogen injection is planned to be continued for about a month until the hydrogen concentration in the suppression chamber is reduced to approx. 2%.

SimplyInfo: “This indicates that the current known level in the torus air gap is over 2% air density. 4% is the point where an explosion becomes possible.”

Mainichi: There is a danger of a hydrogen explosion if hydrogen levels reach 4% with more than 5% oxygen

Title: Progress Status of Mid-and-long Term Roadmap towards the Decommissioning of Units 1-4 of TEPCO Fukushima Daiichi Nuclear Power Station (Outline)
Source: Nuclear Emergency Response Headquarters, Government-TEPCO Mid-and-long Term Response Council, Working Council
Date: August 27, 2012
(Provisional translation)

Nitrogen injection to Unit 1 suppression chamber

As hydrogen concentration and Kr-85 radioactivity density have been changing since April, it is assumed that the hydrogen generated in the early stage of the accident and Kr-85 which remain in the upper part of the suppression chamber are intermittently released into the dry well. In order to investigate whether or not hydrogen and Kr-85 still remain in the suppression chamber, changes in hydrogen concentration and Kr-85 radioactivity density will be measured after injecting nitrogen into the suppression chamber (Early September).

Watch a Japanese television broadcast on the hydrogen levels at Unit 1 here

Published: October 26th, 2012 at 11:57 pm ET


Related Posts

  1. Tepco: Krypton-85 increased at Reactor 1 — Nitrogen injected to reduce explosive hydrogen September 7, 2012
  2. Asahi: Explosive hydrogen may be coming from melted fuel rods and “accumulating near the top of the containment vessel without being driven out” September 25, 2011
  3. Fox: TEPCO releasing hydrogen “to prevent an explosion” at Reactor No. 1 — “Generated by radiation that dissolved water” October 8, 2011
  4. Explosion Danger at Reactor No. 1? Worker says hydrogen levels over 4% in pipe leading to Containment Vessel — Mainichi: “Danger of explosion” if over 4% September 23, 2011
  5. Kyodo: Nitrogen injections stopped for fourth time in recent weeks April 13, 2012

11 comments to Explosive concentrations of gas at Fukushima Unit 1? Hydrogen and Krypton-85 levels fluctuating since April, says Tepco

  • Arizonan Arizonan

    Correct me if wrong, but aren't these fluctuating levels of hydrogen and Krypton-85 more indicative of periodic re-criticalities rather than intermittent releases to the drywell from the early on in the accident?

    • Radio VicFromOregon

      Arizonan, that is a good question and i have no way of answering such a question on that level myself, and, it's one i'd like the answer to now that you bring it up. It should start a lively thread! Arnie Gundersen just started doing a weekly podcast for the week's developments at Fukushima on Sundays. I think i will tune in and see if he addresses this concern. And, he also takes anyone's questions by email and i hear that he is pretty good about getting back with people or referring them on to someone who has a better idea. Btw, he also has a vid up on how to take and preserve rad readings for folks doing this on their own so their work can become part of the public record if they wish.


    • jec jec

      YES! Arizonan..you got it right!

  • "The reactor that is my soul has reached criticality."
    — enenews user johnnyo
    — Date unknown

  • AGreenRoad AGreenRoad

    So many radioactive toys to play with, so little time, what are these boys going to do?

    Radioactive Xenon Gas; Dangerous And Lung Cancer Causing Isotope; via A Green Road

    Depleted Uranium Effects In The Human Body; via A Green Road http://agreenroad.blogspot.com/2012/03/depleted-uranium-effects-in-human-body.html

  • AGreenRoad AGreenRoad

    Actually, radioactive hydrogen is called Tritium…

    That is released by EVERY nuclear power plant, all over the world.

    EVERYONE is drinking and breathing it…

    Velly interesting….

    Wouldn't you like to know more about this????

    • jec jec

      Near Surry Nuclear Plant, Surry Virgina, Tritium events have been noted, but NO ONE does any tests released to the "pubic.". So far local water is tested for floride/lead/bacteria..but NO nuclides. Its "not their job", as the US government is in charge of the drinking water testing for nuclear products..and the State or County can not even MENTION radiation..Not their job. When asked for testing results of wells drilled near the plant. The owner says they follow government regulations or they are "within allowable"..which means they got permission for release or venting of at least ONE nuclides(tritium) without having to worry about legal ramifications. So..sure sounds like TEPCO..doesnt it?

  • razzz razzz

    Certain noble gases and tritium are released constantly (everyday, all day and night) during a nuclear plant's life cycle which includes the reactor and spent fuel pools.

    They are all cancer causing.

    Tritium (3H or radioactive hydrogen) is really nasty stuff because only a dense material like gold can contain it. Tritium molecules pass right through or escape stainless steel, glass, your skin, you name it. That's not so bad but it binds with water (H2O) where you can drink it. Causes brain cancer and stays in the environment for more than 120 years.


    Germany did a study around 2 1/2 miles of their older nuclear plants and found kids less than 5 years old living in this radius were twice as likely to suffer from leukemia and cancers. France did the same test around their plants and confirmed the results. US hasn't done the test, I wonder why? Is it because nuclear plant releases are killing or suffering their own citizens?

    At least move the slider to 31:00 and listen…


    The more you read and hear about nuclear power byproducts the scarier it gets.

  • jec jec

    The USA did test cancer clusters around "powerlines" as it was shown to have a higher number of cases of leukemia..guess what. Powerlines = nuclear plants..Right? Wonder why nothing else was tested..test done..blab blab blab on results..and silence of the lambs…

  • a female faust a female faust

    "Krypton 85 (85Kr) is a radioisotope of krypton….
    … with a half-life of 10.756 years… When uranium-235, or another fissile nucleus fissions, … three atoms of krypton-85 are produced for every 1000 fissions (i.e. it has a fission yield of 0.3%)."

    From Wikipedia.