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A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

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Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#81

Post by bombcar »

dTal wrote: post #25
anonu wrote: post #15

Today I learned: don't bring radioactive material close together... I know about criticality. But I always thought you needed a conventional explosive to kickstart the chain reaction.

You don't need the conventional explosive to kickstart the reaction - you need it to bring the material close together quickly , otherwise the early stages of the reaction blow the material apart before the chain reaction really gets going. That is, if you want to build a bomb.

Build a high yield bomb - you could probably build a relatively effective dirty bomb with the right materials and some auto springs.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#82

Post by bombcar »

credit_guy wrote: post #64
joshuamorton wrote: post #41

Earlier quoted context omitted.

I mean no, it's completely correct. Criticality happens when there's enough plutonium in a small enough space (or not enough plutonium, but in a space with a high density of neutron reflectors). The demon core incident(s), the Cecil Kelley criticality incident, and others don't involve explosives. Just read through the wikipedia list[0], and you'll see that causes included dropping a tungsten brick, an unexpected poo…

Those examples, especially the Demon Core, had much higher quantities of plutonium. The Demon Core [1] was a sphere of 6.2 kg of plutonium surrounded by neutron reflecting tungsten carbide. The photo in this article shows a few small sticks of plutonium. They are not in contact with each other. They are not surrounded by neutron reflecting materials. The chance of criticality in that configuration was insignificant.…

Somewhere between known incidents with 6.2 kg of plutonium and nothing happened incidents with some sticks there’s a point at which something could happen.

And modeling exactly where that point is is difficult, hence the rules and restrictions.

The reaction of those involved lends much more credence to the “stop being idiots and clean this up Homer” reading.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#84

Post by midoridensha »

hit8run wrote: post #43

Maybe just stop building nuclear weapons!? The last thing the world needs is more of this shit.

That would be great, but only if you could get everyone else in the world to also stop and destroy the ones they have.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#85

Post by bombcar »

kragen wrote: post #17

The BLS says: > There were 4,764 fatal work injuries recorded in the United States in 2020, a 10.7-percent decrease from 5,333 in 2019. We should diligently work to reduce work injuries, especially fatal ones. It appears that LANL is a safer workplace than average and its three criticality-accident fatalities in 80 years are not a significant contributor to its overall workplace accident risk. However, it sounds like…

A safety incident that results in the unsafe worker or someone with him dying is usually considered a regrettable occurrence. A safety issue that could irradiate a portion of the city is a bit higher.

Same reason we investigate air and rail incidents much more than we investigate most car crashes.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#86

Post by bumby »

eru wrote: post #65
chadcmulligan wrote: post #53

Earlier quoted context omitted.

You can have it cheap, good or fast pick two.

Pick two or less.. Sure, but I don't see how that relates to the topic at hand? This constraint exists for all organisations. As do budget constraints.

I think the idea is that a for-profit motive forces you to choose "cheap". And if your contract has productivity targets, it constrains you to also select "fast".

These types of contracts are often selected for lowest bidder. I know of one such example where the contractor was pressed during the bid process about how they could be so competitive with their quote. The retort was to the effect of "Our secret is we do more with less." Unless there really is a vast difference in capability of the competing contractors, this naturally puts downward pressure on just doing less (in the form of following certain requirements).

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#87

Post by nerdponx »

xattt wrote: post #52
Arainach wrote: post #6

The photo didn't shut things down. A culture of disregard for safety over years, and a failure by management to take the issue seriously, shut down the lab.

You’re right, but eyeballs want to peek at plutonium and secretly want to see the stuff glow as green rods.

I admit it's alluring. It's just a chunk of greyish metal, how dangerous could it be?

Radioactivity is already a mysterious and fascinating and alluring phenomenon, and somehow radioactive things not looking particularly dangerous only adds to that effect.

There's something strange about ionizing radiation: it's extremely dangerous, yet we have never evolved the ability to detect it and have no intuition for it.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#88

Post by eru »

tjs8rj wrote: post #79
eru wrote: post #28

Earlier quoted context omitted.

> Putting a profit motive anywhere near anything that is safety critical is almost never a good idea. Why? And exactly how do you mean that? Is the safety track record of private industry worse than that of eg non-profit or state owned industry.

It seems theoretically sound: the profitably threshold for accidents is lower than the threshold most people are comfortable risking their lives for a job for, so a for-profit company is pressured to lower standards to the most profitable level (eg having people continue to work around a safety accident). You can always ensure the profitable accident level stays above this with steeper penalties from regulation thoug…

Well, either steeper penalties via regulation, or via competition for labour:

> [...] the threshold most people are comfortable risking their lives for a job for [...]

This suggests that employers with a reputation for danger would have higher labour costs.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#89

Post by eru »

bumby wrote: post #86
eru wrote: post #65

Earlier quoted context omitted.

Pick two or less.. Sure, but I don't see how that relates to the topic at hand? This constraint exists for all organisations. As do budget constraints.

I think the idea is that a for-profit motive forces you to choose "cheap". And if your contract has productivity targets, it constrains you to also select "fast". These types of contracts are often selected for lowest bidder. I know of one such example where the contractor was pressed during the bid process about how they could be so competitive with their quote. The retort was to the effect of "Our secret is we do m…

That seems to be a feature of lowest-bid procurement, no matter whether the bidders are non-profits or whatever.

Re: A near-disaster at a nuclear weapons lab takes toll on America’s arsenal (2017)

#90

Post by wahern »

xwdv wrote: post #76
ineedasername wrote: post #10

I would have though the decision tree for placement of concentrated plutonium was firmly established after the demon core incidents, set roughly in stone as the following: Should I bring high purity plutonium samples together? | V Do you want to die a horrible radiated death taught in textbooks for decades? | | V V No. Yes | | V V Then don’t you’re fired. It seems like Los Alamos may be in need of a fresh printout of…

If a scientist wanted to commit suicide, couldn’t he trigger the criticality event just to see what it’s like and then promptly kill himself off afterward before radiation effects set in? Or is the agony instant?

By all the accounts I've read, there should be some lag time sufficient to commit suicide, unless you're knocked out (they usually wake before the worst of it, though not always), and excepting temperature burns.

But somewhat like quantum suicide, it may be the type of experiment where even a tiny chance of the corner case is still a complete turn-off. Your insides slowly liquifying seems to be one of the worst ways--possibly the worst way--to meet your end.

EDIT: In retrospect, if you're the Los Alamos version of the Hold-my-beer type--judging by the article and especially the photo, such people apparently exist--I suppose it might not be a complete turn-off. (I'm imagining the guy handing his beer and a bullet to his buddy, instructing to give him one or the other depending on the outcome.)

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