191–200 of 357 posts
Really scary. For those unaware of how badly this kind of situation can end up, read about the horrific Goiânia incident in Brazil. https://en.m.wikipedia.org/wiki/Goi%C3%A2nia_accident
At least Western Australia is incredibly underpopulated and remote.
The northern part of Western Australia, especially away from the coast is some of the most sparsely populated land anywhere.
The highway looks like this for pretty much its entire length: https://www.google.com.au/maps/@-24.8925923,119.4609135,3a,7...
Nobody is stopping regularly by the side of this road to wander around and pick up shiny objects.
The search team has thoroughly checked all of the rest stops where the driver took a break, which was easy enough since the truck had GPS tracking.
Radiation detection is my specialty. This source is Cs-137, few hundred mCi. It's easy to detect within a few seconds at distances of a few tens of meters or more with professional detection equipment if there is direct line of sight. If it was knocked off the road, though, the question will be if it fell into a crack or other such place because then the radiation is somewhat shielded and it would take much more meas…
Let’s hope that some random person doesn’t find it and turn it into a necklace or something. The TNG episode “Thine Own Self” comes to mind.
Oh, reminds me a of a time some students lost a Polonium source in the physics lab while I was a Masters student. The HoD had them crawling around the building for days with a Geiger counter, but they never found it. Luckily it was a small source and Polonium has a relatively short half-life, but the department had to go through a whole song and dance of declaring an incident.
According to Wikipedia, Polonium is 5000 times more radioactive than Radium (just 0.001g of Po emits the same number of particles as 5g of Ra). It has a half life of just 138 days so in only 4.6 years the missing Polonium will be equivalent in radioactivity to Radium, which is known to cause cancer. This doesn't sound like something that should be treated lightly.
Radium, in contrast, emits gamma radiation, which presents more of a threat to casual bystanders. All of which is to say: you can't just compare "radioactivity" levels and extrapolate to "danger".
Earlier quoted context omitted.
Presumably if you care about testing for lead, you'd also care enough to have it dealt with while you are living there.
Is there any reason to care about interior lead paint if it’s under several more recent lead free layers and not chipping off?
In a rising damp, wall wicking water scenario the lead may be leached out from the paint and transported to, say, food being grown near house.
The US had long term issues from lead in the water (being ingested) so there's a similar danger here if the lead isn't stable on the wall behind sealing layers.
Related but off topic question. Why isn't radiation used for food preservation?
[1] https://www.fda.gov/food/buy-store-serve-safe-food/food-irra...
[2] https://en.wikipedia.org/wiki/File:Radura_international.svg
Interview question: can you design a system to safely locate and retrieve the capsule?
I'm kind of surprised that something this radioactive isn't pretty easy to hone in on with a good Geiger counter. Someone with better physics want to enlighten me about ranges and sensitivity?
Now find a road that's about 1400KM (870mi) long and pick some random point on there to drop it.
Wait a week for other passing traffic to disturb it, maybe get caught in a tire and sent even further astray.
Now go find it, remembering that even with sensitive equipment, you might need to be a few tens of meters away to pick it up out of the background radiation.
Radiation detection is my specialty. This source is Cs-137, few hundred mCi. It's easy to detect within a few seconds at distances of a few tens of meters or more with professional detection equipment if there is direct line of sight. If it was knocked off the road, though, the question will be if it fell into a crack or other such place because then the radiation is somewhat shielded and it would take much more meas…
This is an interesting algorithm problem. Given the parameters to maximize detection and minimize time/resources, how would you direct a drone or something to find the capsule? How would that change with 2 drones? 4? 8? As many drones as there are flyable Geiger counters in the country?
Radiation detection is my specialty. This source is Cs-137, few hundred mCi. It's easy to detect within a few seconds at distances of a few tens of meters or more with professional detection equipment if there is direct line of sight. If it was knocked off the road, though, the question will be if it fell into a crack or other such place because then the radiation is somewhat shielded and it would take much more meas…
This is an interesting algorithm problem. Given the parameters to maximize detection and minimize time/resources, how would you direct a drone or something to find the capsule? How would that change with 2 drones? 4? 8? As many drones as there are flyable Geiger counters in the country?
Dunno if there's enough energy expected to set it off at the expected speeds travelled. Obviously they don't go "ding ding ding". Might find some spurious beta-radiation sources?
https://www.uth.edu/safety/radiation-safety/personal-radiati...
