4 ms·

> the sudden drop in radioactivity when the capsule left the truck should have triggered an alarm and GPS log Shouldn't a radioactive source should be shielded

> the sudden drop in radioactivity when the capsule left the truck should have triggered an alarm and GPS log Shouldn't a radioactive source should be shielded when not in use, especially when it's being transported? If so there shouldn't be significant radiation coming from the shielded source inside the truck...

eternityforest 4y ago
The Geiger counter doesn't have to be in the truck. It can even be integrated with the equipment being carried, so it can raise the alarm no matter where it is, as long as it has battery. It could even use a low power solid state sensor since the radioactivity is so strong, and when it detects radiation, start dead reckoning until it gets a GPS lock, so you could potentially still get good info with a coin cell level device, although you'd want more, because ideally you'd have a satellite signal. I wonder if there's any way to use the EPIRB satellites for that, or if the data is too limited to add a "Watch out, there's nuclear stuff here, this isn't a stranded hiker" flag?
- noir_lord 4y ago
  Do we have a Gieger Counter Sensor for when the Gieger Counter falls of the truck as well and does that need a Gieger Counter Sensor Sensor? (tongue in cheek). Seems like a simpler solution would be to prioritise checking some shipments over others at departure and arrival. My partner works in shipping/logistics and hazardous chemicals/products are treat completely differently to regular bulk cargo.
  - hgomersall 4y ago
    Having active monitoring with fail-safes seems like a perfectly reasonable thing to me. A short range battery powered system that continuously reports the presence of the source would seem like a good start.
  - cshimmin 4y ago
    It actually could work pretty well. A Geiger counter is essentially a current gain device. Ionizing radiation passes through the chamber and excites free electrons which travel towards high voltage plates. The gain comes when the drifting positive ions collide with other gas particles and knock additional electrons free, starting the process again. Rad source goes missing? Current stops flowing in the GC. HV power failure? Current stops flowing. GC falls out of the vehicle? Current stops flowing. In any of these cases, you make the system shout an annoying beep that everyone within 250m of the vehicle can hear and somebody checks on it.
8organicbits 4y ago
I think it depends on how much radiation leaks through the shielding and how sensitive the Geiger counter is. I'd expect that the goal of the shielding would be to reduce radiation to safe levels, which may still be high enough to detect. But honestly, I have no idea if that's the case.

eternityforest 4y ago

The Geiger counter doesn't have to be in the truck. It can even be integrated with the equipment being carried, so it can raise the alarm no matter where it is, as long as it has battery. It could even use a low power solid state sensor since the radioactivity is so strong, and when it detects radiation, start dead reckoning until it gets a GPS lock, so you could potentially still get good info with a coin cell level device, although you'd want more, because ideally you'd have a satellite signal. I wonder if there's any way to use the EPIRB satellites for that, or if the data is too limited to add a "Watch out, there's nuclear stuff here, this isn't a stranded hiker" flag?

noir_lord 4y ago
Do we have a Gieger Counter Sensor for when the Gieger Counter falls of the truck as well and does that need a Gieger Counter Sensor Sensor? (tongue in cheek). Seems like a simpler solution would be to prioritise checking some shipments over others at departure and arrival. My partner works in shipping/logistics and hazardous chemicals/products are treat completely differently to regular bulk cargo.
- hgomersall 4y ago
  Having active monitoring with fail-safes seems like a perfectly reasonable thing to me. A short range battery powered system that continuously reports the presence of the source would seem like a good start.
- cshimmin 4y ago
  It actually could work pretty well. A Geiger counter is essentially a current gain device. Ionizing radiation passes through the chamber and excites free electrons which travel towards high voltage plates. The gain comes when the drifting positive ions collide with other gas particles and knock additional electrons free, starting the process again. Rad source goes missing? Current stops flowing in the GC. HV power failure? Current stops flowing. GC falls out of the vehicle? Current stops flowing. In any of these cases, you make the system shout an annoying beep that everyone within 250m of the vehicle can hear and somebody checks on it.

8organicbits 4y ago

I think it depends on how much radiation leaks through the shielding and how sensitive the Geiger counter is. I'd expect that the goal of the shielding would be to reduce radiation to safe levels, which may still be high enough to detect. But honestly, I have no idea if that's the case.