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Missing radioactive capsule found in WA outback after frantic search

abc.net.au

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Re: Missing radioactive capsule found in WA outback after frantic search

#11

Post by defrost »

ta_6104829 wrote: post #5
franze wrote: post #3

Anybody has a clue how / what for this is used in mining? And are there alternatives for the future?

I’m not sure about mining, but in dredging it’s used to measure the density of the slurry in a pipe. It’s possibly something similar in mining.

Bang on - it's for density.

You'll also see radioactive sources in household smoke alarms on a smaller scale to estimate smoke load in air, and in mineral exploration in downhole detectors mapping density of surrounding materials, in oil and gas measuring the density profiles of fluids as they flow past, etc.

Flashlights are visible light spectrum sources, gamma emitters are similar in function ( Cs-137 emits a 32 KeV x-ray peak and the 662 keV gamma peak ) as they "shine" through materials opaque in the visible spectrum and can be measured after for absorption.

Re: Missing radioactive capsule found in WA outback after frantic search

#12

Post by ragebol »

wayvey wrote: post #9

If this had been found by the wrong people, what kind of nefarious uses could it have had?

Radiation-poison people? There's not enough material, even if it was Uranium or Plutonium to make any sort of bomb IIRC, you need kilos for that not, (micro)grams.

Re: Missing radioactive capsule found in WA outback after frantic search

#13

Post by ArchD »

jarenmf wrote: post #6

> It was believed the capsule fell through the gap left by a bolt hole, after the bolt was dislodged when a container collapsed as a result of vibrations during the trip. You would imagine someone have thought of this failure mode

Only if their job depended on it. For some people, their jobs mostly depend on following orders, official policy & "best-practices". The job reward is not directly related to the organization's or society's desired outcome. Codified rules and "best-practices" cannot cover everything important. Wisdom & truth are ineffable but sometimes people pretend that everything can be codified, but if that were the case, everything can be done with robots and computers.

Re: Missing radioactive capsule found in WA outback after frantic search

#15

Post by defrost »

bunnie wrote: post #10
lelaurent wrote: post #8

How did they find it?

I'm guessing that even though tho capsule is tiny, its radiation signature could be detected from quite a distance using a Geiger counter.

    Because the output pulse from a Geiger–Müller tube is always of the same magnitude (regardless of the energy of the incident radiation), the tube cannot differentiate between radiation types.
No "signature" detection possible with simple counters I'm afraid.

They used trucks on the road with large doped sodium iodide crystal pack (tubes with a scintallation (flash) detector at the ends) that produce a second by second full spectrum of gamm energies seen.

Processing software is used to filter out cosmic radiation signatures, the ground vehicle signatures, the mean expected background signature of the Western Australian region, and to enhance the target peaks from the Cs-137 source.

Re: Missing radioactive capsule found in WA outback after frantic search

#17

Post by sime2009 »

jarenmf wrote: post #6

> It was believed the capsule fell through the gap left by a bolt hole, after the bolt was dislodged when a container collapsed as a result of vibrations during the trip. You would imagine someone have thought of this failure mode

"Mate, you worry too much. Bazza said he done the bolt real good this time. She'll be right."

Re: Missing radioactive capsule found in WA outback after frantic search

#18

Post by defrost »

jarenmf wrote: post #6

> It was believed the capsule fell through the gap left by a bolt hole, after the bolt was dislodged when a container collapsed as a result of vibrations during the trip. You would imagine someone have thought of this failure mode

These have been used and regularly replaced since the 1970s and this is the first time one has been lost in transit.

Yes, they can do better and hopefully will do so in the future with more rules, regulations and checks.

But, see [1] - you'd imagine someone would have thought about the front of an oil tanker falling off.

[1] https://en.wikipedia.org/wiki/Kirki_(tanker)

Re: Missing radioactive capsule found in WA outback after frantic search

#19

Post by Danieru »

defrost wrote: post #15
bunnie wrote: post #10

Earlier quoted context omitted.

I'm guessing that even though tho capsule is tiny, its radiation signature could be detected from quite a distance using a Geiger counter.

Because the output pulse from a Geiger–Müller tube is always of the same magnitude (regardless of the energy of the incident radiation), the tube cannot differentiate between radiation types. No "signature" detection possible with simple counters I'm afraid. They used trucks on the road with large doped sodium iodide crystal pack (tubes with a scintallation (flash) detector at the ends) that produce a second by secon…

Sounds like the sort of complex setup developed prior for other more exotic use cases...

Re: Missing radioactive capsule found in WA outback after frantic search

#20

Post by [deleted] »

defrost wrote: post #18
jarenmf wrote: post #6

> It was believed the capsule fell through the gap left by a bolt hole, after the bolt was dislodged when a container collapsed as a result of vibrations during the trip. You would imagine someone have thought of this failure mode

These have been used and regularly replaced since the 1970s and this is the first time one has been lost in transit. Yes, they can do better and hopefully will do so in the future with more rules, regulations and checks. But, see [1] - you'd imagine someone would have thought about the front of an oil tanker falling off. [1] https://en.wikipedia.org/wiki/Kirki_(tanker)

[deleted]
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