Friday, May 24, 2013

#Radioactive Materials Leak at Japan Proton Accelerator Research Complex (J-PARC) in Ibaraki, Researchers Accidentally Inhaled Radioactive Gold

(UPDATE 2) For the latest, see my posts here and here.

(UPDATE) From Jiji Tsushin (5/25/2013):


When the radiation level inside the facility rose, the person in charge turned on the ventilating fan and released radioactive materials outside the facility. Professor Taichi Miura at High Energy Accelerator Research Organization, who authorized the ventilation, apologized in the press conference, saying "Radiation level rises even in the normal operation because of radioactive materials with short half life, so we thought they would decay quickly. But it turned out to be imprudent."


Japan Atomic Energy Agency (JAEA), who operates J-PARC, didn't bother to notify the Nuclear Regulatory Agency (secretariat of the Nuclear Regulatory Authority, mostly made of people from NISA) for 2 days, because they did not think there was any leak of radioactive materials.

According to Asahi, the researchers suffer internal radiation of exposure of 1.7 millisievert, and the contamination of the facility is 40 becquerels per square centimeter.

Apparently, the Ibaraki prefectural government was not too happy about the incident and the fact that JAEA didn't bother to notify the authority and the prefectural government, and held an angry press conference at 2AM on May 25.

The official story of the accident, from Asahi Shinbun (5/25/2013, 1:37AM):

原子力機構で放射性物質漏れ 研究者ら4人が内部被曝

Radioactive materials leak at JAEA facility, 4 researchers suffer internal radiation exposure


Japan Atomic Energy Agency disclosed on May 25 that there was a leak of radioactive materials outside the nuclear and particle research facility at J-PARC in Tokai-mura in Ibaraki Prefecture. At least 4 researchers inside the facility suffered internal radiation exposure. The leak has stopped, and there is no danger of the leak spreading further. The maximum radiation exposure was 1.7 millisievert, according to JAEA. JAEA is currently investigating how much radioactive materials have leaked outside the facility.


According to JAEA and the Nuclear Regulatory Authority, the leak took place at 11:55AM on May 23. They were conducting an experiment of generating elementary particles by hitting gold with proton beam. The equipment malfunctioned, and the output of the proton beam increased to 400 times the normal strength, and gold was vaporized. Radioactive materials [radioactive gold vapor] leaked [from the equipment], and were inhaled by the researchers. There were about 30 researchers when the accident happened.


Contamination of the facility is about 40 becquerels per square centimeter maximum. Currently the facility is off-limit. At the time of the accident, JAEA didn't think there was a leak of radioactive materials, and did not report to the government. J-PARC is a facility to study elementary particles with large accelerators.

Equipment malfunctioned. That's the official story.

Let us now turn to "baseless rumors" among knowledgeable researchers (like this one, from Professor Hayano of Tokyo University) for what may really have happened. According to the unverified rumors, it was not the equipment that malfunctioned. Researchers made a mistake, and instead of hitting the target (gold) with low, continuous proton beam over a long period of time they accidentally hit it with high-intensity proton pulses.

According to NHK quoting the Ibaraki prefectural government, the monitoring post outside the facility showed a slight increase in radiation level between 3PM and 6PM on May 23. The radiation level is normally between 70 to 130 nanogray/hour, but it rose by 10 nanogray/hour on May 23.

Never trust the Japanese with a gigantic facility like a proton accelerator. Or a nuclear reactor. They are not only incapable of operating them properly, but when an accident happens they don't tell you.

(How do you get rid of radioactive gold in the body? Does anyone know?)


Anonymous said...

40 Bq/cm2 is 400,000 Bq/m2, in the high range of zone 3 at Chernobyl, whereby people are not allowed to live.


Anonymous said...

40 Bq/cm2 is for the contamination detected inside the facility and the Chernobyl number you mention is for surface contamination on larger areas.

Also, that Chernobyl number is for Cesium-137 alone, and we still don't know what kind of isotopes they have detected at J-PARC. Probably there are many short lived isotopes involved which would decay quite fast.

Anonymous said...

"The radiation level is normally between 70 to 130 nanogray/hour, but it rose by 10 nanogray/hour on May 23."

That doesn't make much sense. I checked the source on NHK and it is the same.
Hard to understand. Does it means it rose from 70 to 80 ? or from 130 to 140 ? or it rose 10 nanogray every hour, if so for how many hours ?

Does anyone know what was the absolute highest reading ?

arevamirpal::laprimavera said...

Anon at 5:26PM, it is irradiated gold.

Anonymous said...

Anon at 6:35pm, the RATE increased from 70-130 nGy/hr to 80-140 nGy/hr.

OP, the statement "Never trust the Japanese with a gigantic facility like a proton accelerator. Or a nuclear reactor." is quite prejudice. First of all, these are two very different technologies requiring very different operational procedures. Secondly, this is an international laboratory, with many non-Japanese collaborators.

Also, putting the two incidents together to make a judgement on the Japanese capability is a fallacy. It just so happens you are monitoring Japan because of Fukushima and came across one of many accidents in particle accelerators. Are you aware of the accidents that have occurred at other particle accelerators around the world, including the LHC?

arevamirpal::laprimavera said...

Anon at 10:29PM, yes I am aware. But probably only in Japan where a manager in charge turned on the fan to change air when they noticed the radiation level was increasing inside the room, thus leaking the radioactive gold vapor outside the facility.

Anonymous said...

Abe apologist again. Good grief.

By the way, Japan is set to implement another gigantic system of numbering every single citizen and create a database of all vital information of every single citizen, to be managed by the central government. Good luck with that.

Anonymous said...

laprimavera, where do they say that it was radioactive gold? During the experiment, they bombarded gold with protons, but I'm not sure if the contamination leaked is radioactive gold.

arevamirpal::laprimavera said...

See the latest post. J-PARC/JAEA haven't tested the nuclides yet, but researchers are saying they were probably radioactive gold, and tritium.

Anonymous said...

@5:26 we do not know how the JAEA boys measured those 400,000 Bq/m2 so we do not know what isotopes are included and what are not. Regardless, they evacuated the facility, so the figure is obviously high enough not to stay there. Also, we do not know what isotopes we are talking about, so assuming they are short lived is guesswork.
Finally, iodine is short lived too, but you do not want to breath it anyways.

Besides, it seems that they were aware of the nuclear contamination when they turned on the fan but they forgot about the same when deciding whether to notify external entities. This looks pretty much similar to Tepco behaviour to me.


Anonymous said...

"Never trust the Japanese with a gigantic facility like a proton accelerator. Or a nuclear reactor. They are not only incapable of operating them properly, but when an accident happens they don't tell you." ehem, that is not in the original Japanese, at least not the part you posted. While it's clear that certain Japanese operators are incapable of operating any of these facilities safely, I don't think anyone has been able to make the case that this is genetic.

arevamirpal::laprimavera said...

Anon at 5:40PM, can't you tell that it is MY comment? Translated articles are always indented. Who said it's genetic? Not me.

Anonymous said...

People in general are fail. Same shit would happen anywhere. I doubt any authority would seriously tell us if they screwed up on anything. That's the kind of thing you only see in movies.

They're all worried about their personal career and having to take the fall. Humans are so simple they think everything's fine if you can just find a scapegoat to dump all the blame on. Public forgets easily.

If there's ever a major disaster, the first we'll hear of it is when it's literally on top of us and there's no escape.

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