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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)

#91

Post by 01100011 »

dralley wrote: post #31
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.

It's not necessary. You just need to increase the neutron density to a point where the fission reaction can take place. You can do that by: * Reflecting neutrons (as in the demon core incidents) * Bringing too much fissile material together in the same place (the cause of other accidents, the "little boy" nuclear weapon) * Compressing a subcritical mass of fissile material with explosives such that the increased dens…

Don't forget about neutron moderators like water or graphite. Pouring water on a pile of fissile material can be enough to induce criticality. The fast neutrons interact with hydrogen atoms in water to produce thermal neutrons which are much more likely to participate in a chain reaction.

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

#92

Post by bumby »

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…

It appears that LANL is a safer workplace than average

"Average workplace" probably isn't the appropriate comparison.

Some industries (like construction) probably wouldn't be a good comparison. By contrast, the article states LANL had more incidents than all other 23 DOE combined.

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

#93

Post by bumby »

eru wrote: post #89
bumby wrote: post #86

Earlier quoted context omitted.

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.

Agreed. But "going to bid" will almost certainly constrain to a profit motive.

Even if there was a case where a bidder is non-profit, I can't fathom how they would bid on a project with the intent to be in the red. Maybe there are more exotic ways to run a lab, but it seems like the choice is to either figure out how to work with a profit motive or be a primarily civil servant lab.

The govt can sometimes try a "best value" award instead of low bidder, but that tends to make lawyers skittish because it opens up avenues for the losing bidders to protest the award.

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

#94

Post by iab »

credit_guy wrote: post #22
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're absolutely right. The idea that bringing a few bars of plutonium next to each other for a photo could result in a criticality event is completely bogus. The real issue of course, is that you want people at a facility that handles plutonium to adhere very strictly to procedures. If you don't freak out when they take some selfies, next day they'll do something else. And one day, one of these things will be stupi…

History is replete with examples of this

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

#95

Post by Nekhrimah »

thret wrote: post #67

Reading what happened to Ouchi makes me think two things: 1. Anyone who has not gotten that far, skip the "Ghastly deaths after the blue glow" part. 2. Euthanasia for someone exposed to lethal radiation should be the recommended treatment. Give the patient a choice, but also the option.

> Euthanasia for someone exposed to lethal radiation should be the recommended treatment.

That was my thinking too. The poster child for humane avoidance of suffering.

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

#96

Post by [deleted] »

jahewson wrote: post #62
bmc7505 wrote: post #60

Earlier quoted context omitted.

Your flowchart neglects to mention the potential upside: Do you want to experience the results of runaway nuclear chain reaction firsthand? Become a Wikipedia entry? Impress the labmates with your prowess at tickling the dragon's tail?

Hey, there’s a first time for everything!

[deleted]

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

#97

Post by leetrout »

justinator wrote: post #63
bumby wrote: post #47

Earlier quoted context omitted.

I’m not sure why you’ve been downvoted but this is a very prevalent attitude at hazardous facilities that are run by contractors. In particular, when the hazards are relatively low probability events and there are perverse incentives to roll the dice in the name of productivity. In a previous job in a hazardous facility, I’ve had very senior managers sit me down to tell me I don’t want to get the reputation for slowi…

> I’m not sure why you’ve been downvoted Because "Covid 19 was engineered in a lab, then released" is nothing but a conspiracy theory.

You jumped to some conclusions.

OP said a lab accident. This could have been from an animal sample.

Everyone seems to conflate lab leak with lab manufacture (or jump further to purposeful leak).

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

#98

Post by kragen »

bombcar wrote: post #85
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.

It's true, but the risk of that is fairly small. There were 60 publicly disclosed criticality accidents from 01945 to 01999 https://en.wikipedia.org/wiki/Criticality_accident#Known_inc... causing a total of 21 deaths, though for some reason that list doesn't include Chernobyl, which killed 31 people directly and about 6000 people over the years.

But you aren't going to get a Chernobyl-style disaster from a criticality accident in a glovebox; Chernobyl happened inside a containment vessel that harnessed 3 gigawatts of thermal energy in normal operation, along with massive quantities of graphite moderator which caught fire and distributed radioactive material all across Europe.

Also, Los Alamos has a population of 13'200; the nearest city is 93 km away with about 930'000. Those people are very important but evacuating Los Alamos would not be nearly as difficult as evaluating Pripyat (population 49'360) — unless strict official controls on information dissemination delayed the news until it was too late, anyway.

Basically I think people are worried about nuclear fuel processing not because of its real dangers (which are significant but of a smaller order of magnitude than the dangers of fertilizer shipping, pesticide manufacture, and inadequate building codes in earthquake zones) but because of a well-justified belief that the government lies about them, along with the well-documented fact that nuclear energy was originally developed for mass killing.

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

#99

Post by kragen »

bumby wrote: post #92
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…

It appears that LANL is a safer workplace than average "Average workplace" probably isn't the appropriate comparison. Some industries (like construction) probably wouldn't be a good comparison. By contrast, the article states LANL had more incidents than all other 23 DOE combined.

Maybe they're all being counterproductively paranoid.

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

#100

Post by quickthrower2 »

crooked-v wrote: post #3

So I guess it turns out that Homer Simpson was more realistic than we thought... all the way through to only avoiding nuclear accidents through sheer luck.

Homer is safer. He chucks a single rod out on the street in the opening scene, keeping it separate from the rest. At work he is lazy, so by doing nothing, he is not combining rods together.
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