Short Stuff: Hisashi Ouchi

**Josh** (0:04)
Hey, and welcome to The Short Stuff. I'm Josh, and there's Chuck and Jerry sitting in for Dave, and this is Short Stuff, a really sad edition.

**Chuck** (0:13)
Yeah, for sure, because this is about a nuclear accident, and one very famous victim of that accident, a man in Japan named Hisashi Ouchi, who at the time was a 35-year-old worker at a nuclear facility, and he got a massive blast of radiation in 1999 It was called a criticality accident. And what was the name of the town?

**Josh** (0:43)
In Takaimura.

**Chuck** (0:45)
Takaimura, okay, great.

**Josh** (0:47)
Yeah. No, Tokaimura, sorry.
And that's called the Tokaimura Nuclear Accident is what it's called. And like you said, it was a criticality because there wasn't a nuclear explosion or anything like that. It was an uncontrolled nuclear fission reaction that these guys accidentally created while they were doing their job processing uranium oxide into usable uranium-235 fuel to be used in an actual nuclear reactor. This is not a nuclear plant. It was the kind of plant that produces fuel for nuclear plants.

**Chuck** (1:23)
That's right. This is the morning of September 30th, 1999
And what they specifically were doing in that moment was they were dissolving that uranium oxide, like you were saying. And this was the procedure.
What I'm describing now is the approved procedure, actually. So they were supposed to have dissolved that uranium oxide in a geometrically safe vessel. And then what you end up with is a urinal nitrite solution. And you put that into a buffer tank, and then transfer little bits of that into a precipitation tank. This company, is it JCO, is the name of the company?

**Josh** (2:05)
Yeah.

**Chuck** (2:06)
They said, all right, we're going to speed this up, and this procedure is not approved. But what we want you guys to do is mix the solution in stainless steel buckets, and then pour it directly into the precipitation tank.

**Josh** (2:20)
And not only pour it directly in the precipitation tank, pour so much in there that we have like five to six times the approved amount in that precipitation tank at once, right?

**Chuck** (2:32)
I think it's like seven times.

**Josh** (2:34)
Okay. A lot, a lot more than was supposed to be in there. And I just want to point out, like you were saying, there was an approved procedure, and JCO said nuts to that, we're going to do this faster one, right? That's just what they were doing with their workers. It's crazy because this is nuclear, uranium-235 fuel that they're making. And so when they put in these three workers, including Hisashi Ouchi, when they put in the seventh bucket of this stuff, into the directly in the precipitation tank, there were 16.6 kilos or 36.6 pounds of uranium in there, which is way more than was allowed to be in there. I think it was 2.4 keys or kilograms that was allowed to be in there. They had 16.6, Chuck.

**Chuck** (3:19)
Yeah, so that reached critical mass pretty quickly and started a self-sustaining nuclear chain reaction. And like you said, it wasn't like an explosion or anything like that, but it was a huge burst of neutron and gamma radiation, like incredible Hulk levels. And it went on and off for about 20 hours until the emergency workers finally drained water from the tank's cooling jacket and then added boric acid to absorb the neutrons.
But very sadly, Ouchi received a dose equivalent of 17 sieverts. It's kind of hard to get an exact calculation, but it was an incredibly large amount of radiation, like so much that he's been called the most radioactive man in history, which is a bit of a misnomer because he had this burst of radiation, but it's not like he was walking around, like radioactive to other people or anything like that.

**Josh** (4:17)
It's a little surprising to me, but okay, I'll take that. I did a little bit of Josh math here, Chuck. Oh, boy. Well, it's not even Josh math, it's more Josh checking.
So you said that Ouchi received 17 sieverts of radiation, right?

**Chuck** (4:35)
Yeah, I'm not laughing at that, I'm laughing at your math by the way.

**Josh** (4:39)
No, I understand.

**Chuck** (4:39)
Yeah.

**Josh** (4:40)
One millirem is equal to 0.0001 sieverts, okay?
You get 20 millirems from a chest x-ray. He got 17 sieverts all at once.

**Chuck** (4:56)
Wow.

**Josh** (4:57)
I mean, that's just such a mind-boggling amount of radiation that I can't believe he didn't die immediately.
I say we take a break and come back and talk about Ouchi's agonizing 83 days of life that followed that radiation exposure. All right.