Macstack.net
A Mac community for over 23 years. No kidding. We started talking in 1999.
TOS wrote:Pithecanthropus wrote:ukimalefu wrote:
I'm embarrassed to say that it took someone to explain this to me. Bad nerd.
and what was that explanation? i'm asking for a friend
dv wrote:TOS wrote:Pithecanthropus wrote:ukimalefu wrote:
I'm embarrassed to say that it took someone to explain this to me. Bad nerd.
and what was that explanation? i'm asking for a friend
The answer to the addition question is "Star Wars."
Episode 4, 5, 6, 1, 2, 3, 7, 3.5 (Release order.)
The metal rods in the top photo are plutonium. Rods can roll. These rods could roll closer to each other and perhaps produce the kind of runaway neutron reaction that killed Slotin and Daghlian. Putting a hand in to separate them could make the reaction worse because the water in a human body reflects the neutrons.
I had formal safety training, informal discussions with more experienced people, and made it a point to internalize rules of thumb. Keep pieces of plutonium separate. Abide by glovebox limitations; every glovebox has a sign with the limits of plutonium allowed in it. For solutions, keep them dilute and in flat containers. Flat/thin is safer; the closer a shape is to spherical, the less material is needed to go critical. IIRC, there were racks to put rods in if you were working with that shape of metal, so that they didn’t accidentally roll together.
That photo is at the center of two articles from the Center for Public Integrity (NMPolitics.net, Washington Post). They are based on an investigation reported here. According to those articles, a technician ignored glovebox limits and arranged the plutonium to take that photo for management. A Los Alamos manager is also quoted in the articles as saying that the criticality safety group was an unnecessary expense. A number of the senior people in the criticality safety group were of my vintage and were expected to retire about when I did. According to the articles, management’s signal was heard loud and clear, and the rest left.
[links not included]
DEyncourt wrote: A creepy pic, according to this article's author:The metal rods in the top photo are plutonium. Rods can roll. These rods could roll closer to each other and perhaps produce the kind of runaway neutron reaction that killed Slotin and Daghlian. Putting a hand in to separate them could make the reaction worse because the water in a human body reflects the neutrons.
I had formal safety training, informal discussions with more experienced people, and made it a point to internalize rules of thumb. Keep pieces of plutonium separate. Abide by glovebox limitations; every glovebox has a sign with the limits of plutonium allowed in it. For solutions, keep them dilute and in flat containers. Flat/thin is safer; the closer a shape is to spherical, the less material is needed to go critical. IIRC, there were racks to put rods in if you were working with that shape of metal, so that they didn’t accidentally roll together.
That photo is at the center of two articles from the Center for Public Integrity (NMPolitics.net, Washington Post). They are based on an investigation reported here. According to those articles, a technician ignored glovebox limits and arranged the plutonium to take that photo for management. A Los Alamos manager is also quoted in the articles as saying that the criticality safety group was an unnecessary expense. A number of the senior people in the criticality safety group were of my vintage and were expected to retire about when I did. According to the articles, management’s signal was heard loud and clear, and the rest left.
[links not included]
Downtown was crowded with people, and comic book nerds were packed everywhere, lining up to get into the Con. I turned the corner into full view and was greeted with open iphones, gaping mouths and spontaneous applause! It was awesome! The gigantic fidget spinner was an absolute hit that the crowds loved!
"OH DAMN! MIKE! LOOK! FIDGET SPINNERRRRR!" x 1000.
I love being stopped for photos, and with the fidget spinner costume I had a special trick: Invariably the photographer would click through and snap a picture, thank me and then slowly realize the whole truth.
"Does it.... spin?"
I would slowly nod. "Yes. It does!" Then I'd back up and give it a big whirl and they would shriek or just shake their heads in amazement. It was incredible!
maurvir wrote:DEyncourt wrote: A creepy pic, according to this article's author:The metal rods in the top photo are plutonium. Rods can roll. These rods could roll closer to each other and perhaps produce the kind of runaway neutron reaction that killed Slotin and Daghlian. Putting a hand in to separate them could make the reaction worse because the water in a human body reflects the neutrons.
I had formal safety training, informal discussions with more experienced people, and made it a point to internalize rules of thumb. Keep pieces of plutonium separate. Abide by glovebox limitations; every glovebox has a sign with the limits of plutonium allowed in it. For solutions, keep them dilute and in flat containers. Flat/thin is safer; the closer a shape is to spherical, the less material is needed to go critical. IIRC, there were racks to put rods in if you were working with that shape of metal, so that they didn’t accidentally roll together.
That photo is at the center of two articles from the Center for Public Integrity (NMPolitics.net, Washington Post). They are based on an investigation reported here. According to those articles, a technician ignored glovebox limits and arranged the plutonium to take that photo for management. A Los Alamos manager is also quoted in the articles as saying that the criticality safety group was an unnecessary expense. A number of the senior people in the criticality safety group were of my vintage and were expected to retire about when I did. According to the articles, management’s signal was heard loud and clear, and the rest left.
[links not included]
It's creepy because some complete dipshit of a manager who doesn't understand, or care, about safety asked someone to pose that picture against the SOP. The article goes into detail about how said uncouth individual convinced all of the other people in the department responsible for criticality safety to quit or retire early, thus practically ensuring that an accident happens in the future.
Fortunately, it seems that there are pegs molded into the metal rods to keep them from rolling far, but it doesn't take much for that stuff to go horribly wrong. It is an example of where you need highly trained personnel, not numbskulls who managed to get their MBA, in charge of things.
ukimalefu wrote:
