funranium: (Duck 'n' Cover)
[personal profile] funranium
***Cross-posted from Funranium Labs***

While I like to keep my discussions here coffee, beer, and historical science related some things just can’t be ignored especially when people keep poking me for answers. So, I have some thoughts that are quite lacking in insobriety.

First, I am not a nuclear engineer, contrary to how more than a few people have referred to me; I am a health physicist. It is the purpose of my field to keep radiation doses as low as reasonably achievable (ALARA, as the acronym goes) for radiation workers and the public. More often than not, this means protecting the radiation sources from people as humans are rather dangerous when we ignorantly play with fire. So, I cannot definitively speak to the quality of the reactor’s construction or it’s current post-earthquake condition, though I’m pretty sure no one builds reactors with a M9.0 quake in mind (certainly not the outbuildings that held the cooling & filtration systems that have been damaged). The job of a health physicist is now to protect the public from an accident that has gone beyond the confines of the reactor. For that, I can say things:
  1. If you do not live in northern Honshu, you do not have cause for panic. The radiation release from the reactor has been localized to the immediate vicinity. A downwind plume exposure pathway emergency planning zone (~10mi radius) as already been evacuated. A wider 50 mile radius will be drawn for confiscation of foodstuffs to minimize any potential ingestion of radioactive iodine & cesium.
  2. Please be understanding of the fact that thousands are dead from a tsunami and earthquake with associated services badly disrupted. Terrifying as a nuclear reactor having trouble may seem to you via television report, there are much more lethal and immediate problems than the reactor to the people who are still in the middle of this. Just getting there to help is a logistical nightmare. Contamination can be cleaned up, but people can’t be unkilled. Life saving takes precedence over property & environment.
  3. Normal operations of a nuclear reactor involves the operation of air and water monitoring stations in the facility itself and area environmental monitors for many miles around. A tsunami is likely to have broken more than few of those, but many more mobile units were rushed to the scene. This is how we are keeping track of what has been/is being released to the surrounding area from the reactor.
  4. Radioactive materials are being released to the air in the form of radioactive steam and water. Dissolved metals in the water and small particulates are particularly prone to becoming activated and thus radioactive, especially without a functional cooling and filtration loop to clean the water up. The radioactivity is very short lived, in general on the order of minutes to about a week, but rather nasty while it is present.
  5. Reports have indicated the presence of small quantities radioiodine and radiocesium in monitoring. This indicates that some of the nuclear fuel cladding has been damaged due to overheating.
  6. Unless ordered by a medical professional, DO NOT self-administer prophylactic iodine or Prussian blue treatments to protect against radioiodine & radiocesium uptake. These treatments carry some significant metabolic risks at the body saturating doses necessary to offer protection.
  7. Please don’t mob the health professionals. They are badly outnumbered and doing their best. People with burns and crush injuries take precedence over potential radioactive materials uptake every time. Your latency for cancer is 40 years; their latency for a crushed arm may only be minutes. Do not be upset when they press-gang you for assistance at the triage station rather than treat you like victim, because you are still ambulatory and capable.
  8. The symptoms of acute radiation sickness (ARS) begin with vomiting. There’s an awful lot of things that may cause vomiting in a disaster situation like this, not the least of which is stress and psychosomatic response. At this point we will segregate you and watch for further advancement of symptoms. At present, only one person who has presented with symptoms that has had an actual radioactive materials uptake; his dose was less the 1/10th the what is normally associated with associated with ARS.
If you want to help with all of this, please, instead of buying a Stein of Science or Black Blood of the Earth go donate to the Red Cross. You will do far more good than staring at the TV with growing panic. Several colleagues I rather respect are already on their way to Japan to help with the reactor problems and I wish them the best. As endless a supply of caffeine as I can make is going with them.

I also recommend watching for announcements to come through the International Atomic Energy Agency, American Nuclear Society, and World Nuclear News.

Date: 2011-03-14 07:43 am (UTC)
drcuriosity: (Default)
From: [personal profile] drcuriosity
Thank you for posting this. Given some of the unreasoned panic out there, it does help. I've even seen a couple of people here in New Zealand suggesting that people should stock up on iodine pills. Gah.

Date: 2011-03-14 03:50 pm (UTC)
From: [identity profile]
In Seattle, too. I don't know much about human medicine, but we use Potassium and Sodium Iodide in cattle (rarely!) and it is NASTY stuff. I can't believe people recommend taking it "just in case". Then again, I have a hard time wrapping my head around a lot of things people do, so maybe that's just me...

Date: 2011-03-14 06:25 pm (UTC)
From: [identity profile]
It doesn't help that a bunch of these Kiwis have an unreasonable fear of nuclear stuff. Not that I don't understand the whole nuclear-free thing (think it is stupid personally, of course, but hey) but I think in some cases the paranoia really goes too far.

Date: 2011-03-14 07:55 am (UTC)
From: [identity profile]
Thank you.
From: (Anonymous)
Wow, I really hope you're wrong about that. Earthquakes of this magnitude are rare, but definitely not rare enough that they shouldn't be anticipated. Especially when you're building a nuclear reactor.
From: [identity profile]
Anticipated vs. able to build to definitively survive a quake of this magnitude are another matter.

The reactor building appeared to have survived fine with seismic SCRAM systems slamming the control rods into place exactly as they should have. Sadly, it is the supporting systems buildings that bore the brunt which are causing the reactor to have trouble. And their condition, and the inability to fix them, are a function of how badly damaged the rest of the region is. The moment the reactor SCRAMs you have X amount of time to evaluate all the supporting systems and set everything running again. A M9.0 quake badly impairs your ability to do that.

This is more than design basis for a reactor, this is regional infrastructure and disaster response. You can only spend so much planning for disasters.
From: (Anonymous)
I understand the economic reality of preparing for this sort of thing and the unpredictable outcomes of an earthquake of that size. But I think at some point you have to say, if we can't successfully prepare for this sort of thing we just shouldn't be doing this. Accdg. to this list,, there have been 6 or 7 earthquakes magnitude 8.8 or greater in the last 50 years alone. At that frequency it seems to me one ought to be able to definitively say they can survive such an event with minimal harm, or else you just shouldn't be building the thing.

Granted, at this point there hasn't really been any serious damage done and it looks like it will probably stay that way, which is great; so I think the emergency plans and backup systems have been largely successful in avoiding a serious incident.

I just have a difficult time with the idea that somebody would approach building a nuclear reactor with the attitude that they can't have a certainty about surviving a 9.0 quake without having a serious incident, but hey, let's go ahead and do it anyway. If we were talking about a 10.0 quake, maybe, because that's really crazy unlikely. But quakes of 9.0 or so don't really seem to be that uncommon.
From: [identity profile]
Designing for earthquakes has nothing to do with earthquake magnitude, and everything to do with earthquake induced ground acceleration. The reactors concerned were designed to withstand the same response spectra as that produced in a 1952 7.3 magnitude quake in Kern County, US. So their design spec was to resist up to .18 g accelerations. They did this quite well in earlier quakes.

The Sendai quake produced .2 to .3 g accelerations. There has been no catastrophic failure of the reactor buildings or chambers, so although their design accelerations were exceeded, it was the supporting infrastructure that failed.

The point to think about is that much smaller quakes (the 6.3 we just had in Christchurch, NZ, two and a bit weeks ago) can produce much higher accelerations than some much larger quakes - we recorded .5 to 2.2g ranges of accelerations, with some of our stations exceeding 1 g in all three directions. NZ has design standards requiring most new buildings to be capable of surviving .5 g, and older buildings are slowly, but not always, being upgraded to withstand .2 or .3 g, depending on engineering type. Japan has similar. In both countries, some of our new infrastructure is built to withstand 1 g in any direction.

The other question when designing this sort of thing is _how_ often does it need to withstand these accelerations? Given that the recent NZ quake exceeded the return period for not just the 500 year acceleration event, but also the 2000 year event return period, and was probably the sort of event that only happens once every ten thousand years, do we really have to design for it?

From: (Anonymous)
Hmmm, well I'm not an expert on earthquakes or architecture so I was just going by the richter magnitude. I don't know much about the probabilities of reaching various ground accelerations. Certainly if you have an event that is likely to happen only once every 10k years you wouldn't necessarily design for that. OTOH, if you have an event that happens 6-7 times over a 50 year span I would certainly hope that the combination of structural design, failsafe systems, and emergency recovery plans would have a high degree of certainty of avoiding a catastrophic release of radiation.
From: (Anonymous)
You're right. If it happened every 10 years or so in Japan alone, not designing for it would constitute egregious criminal negligence. Not designing for something that happens every 10 years or so along *some* fault line *somewhere*, well yeah I guess that would be marginally less negligent. Except maybe if you were building in a location that was like, RIGHT ON TOP OF THE INTERSECTION OF TWO MAJOR FAULT LINES.

Date: 2011-03-14 08:49 pm (UTC)
From: [identity profile]
Thank you! This is the sort of information that should be disseminated by the professional news media. Unfortunately, they are in the business of selling fear, not information, and in stead we get eye-candy maps of horror showing radiation plumes scouring the Western Pacific Rim and coast of North America and headlines like "Meltdown" and "Nuclear Disaster."

Nuclear power plants (excluding those built by the USSR)are built to extraordinary safety standards. The containment buildings can withstand direct hits from cruise missiles powerful enough to destroy an entire city block. Their fail-safe systems have triple redundancy. The Three Mile Island incident, oft cited by opponents of nuclear power was in fact an example of how well the safety systems work. Were you standing atop the reactor building at the time, you would have received far more harmful radiation from the sun than from the power plant.

I will be amazed if, when the dust settles and the health and science professionals are able to make a final assessment on radiation exposure, anyone will be noticeably affected by it.

Date: 2011-03-24 03:10 am (UTC)
From: [identity profile]
Thanks, friend. It is nice to have someone working to spread sanity.

Date: 2011-03-25 08:17 pm (UTC)
From: [identity profile]
Thank you. It ain't easy.

The desire to actually drop what I'm doing and joining the decon crews is rather high. Certainly more appealing than trying to fight unreasoned panic of others.

December 2012

234 5678

Most Popular Tags

Style Credit

Expand Cut Tags

No cut tags
Page generated Sep. 24th, 2017 11:05 pm
Powered by Dreamwidth Studios