Naked Science Forum

Non Life Sciences => Technology => Topic started by: thedoc on 18/08/2016 14:23:02

Title: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: thedoc on 18/08/2016 14:23:02
A A KAREEM asked the Naked Scientists:
   If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray scanner?
What do you think?
Title: Re: If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray
Post by: alancalverd on 18/08/2016 16:02:24
Why bother? It is not a prohibited substance.
Title: Re: If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray
Post by: Ophiolite on 18/08/2016 16:11:56
Why bother? It is not a prohibited substance.
Tell that to a friend of mine who spent seven years in an Indian jail for gold smuggling!
Title: Re: If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray
Post by: chiralSPO on 18/08/2016 16:12:12
You need to put it in a large gold box.
Title: Re: If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray
Post by: alancalverd on 18/08/2016 16:21:12
But then you'd have to pay for excess baggage.

Better to hollow it out, paint it grey, and say it's a lump of lead. I carry lead blocks through "security" every week, on my way to test x-ray machines.
Title: Re: If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray
Post by: RD on 18/08/2016 17:01:34
Better to hollow it out, paint it grey, and say it's a lump of lead. I carry lead blocks through "security" every week, on my way to test x-ray machines.

No need for paint if they reshape the gold into an Oscar statue (https://en.wikipedia.org/wiki/Academy_Awards), which are only gold-plated worth ~$1K . A solid-gold version would be worth ~$250K
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: chris on 18/08/2016 19:51:00
Do airport security know how much an Oscar statue should weigh? The solid gold equivalent is going to be seriously heavy...

Alan - do you put your lead blocks in hand luggage?
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: Bored chemist on 18/08/2016 20:01:52
Why is this thread continuing to provide information to someone who is trying to break the law.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 18/08/2016 23:12:20
Why is this thread continuing to provide information to someone who is trying to break the law.

It isn't. There is no law against carrying a gold bar onto an aircraft. In fact it's the best way to transport the stuff.

Smuggling is another matter. That's all about taking gold bars (or anything else of value) off an aircraft without telling anyone.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 18/08/2016 23:40:15

Alan - do you put your lead blocks in hand luggage?

In the event of having to abandon ship, I'd rather not have them in my pockets.

I'm not allowed to carry recognisable hand tools like screwdrivers and presumably spanners (I recall spending school holiday journeys assiduously dismantling DeutschBundesBahn toilets, though I can't remember why. Perhaps airport "security" guys went to the same school). If I want a knife I have to steal it from the airside restaurant, buy a Swiss army knife airside at Zurich, or pay for a First Class lunch. But the thing that really excites "security" is paper masking tape. For reasons beyond my comprehension, unemployable zombies at Dublin airport confiscate the stuff on a fortnightly basis (I can't afford to work there much more often!) And the French authorities object to tinned cassoulet unless you put it in hold baggage or buy it airside at inflated prices.     

For those wanting to carry contraband onto an aircraft, the best wheeze I have seen was at Prestwick where a guy handed two vials of what could well have been nitrogylcerine to the "security" officer. He said "they are both less than 100 ml, and they mustn't be x-rayed as they are homeopathic remedies".  Sure enough, they bypassed any form of surveillance.

The 100 ml rule is crucial to the life of zombies. At JFK my girlfriend was told she could not take 120 ml of hair conditioner onto the plane, so she walked back to the pharmacy and bought two 100 ml  bottles. In full view of the "security" officer she decanted the offending liquid into two 60 ml aliquots and presented 2 x 60 ml liquid plus one empty bottle to "security". Then having passed through the pearly gate, she decanted them back into the offending bottle. 

I'm not allowed to promote a named product here, but I sell a really good whole-body x-ray security scanner (no inverted commas!) that you can walk through with your luggage. We have used it to to demonstrate that up to 50% of US prisoners have either mobile phones or knives inside their accessible body cavities. But I'm sure the travelling public would prefer to continue standing in a queue then emptying their personal possessions and sex toys onto a conveyor belt whilst the girl in front tries to remove her thigh boots.

Skeptic, moi? You bet.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: RD on 18/08/2016 23:45:38
.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: Tim the Plumber on 19/08/2016 09:11:27


Now that beats the hand luggage rule.

Yet another reason not to go to goal...
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 19/08/2016 09:28:48
...which is why I said it's an offence to carry gold off the plane without declaring it.

Unless, of course, you are wearing it as jewelry, which seems to escape all scrutiny either as a weapon (I've seen hair slides that would grace a pathologist's bench if not a butcher's slab, and some rings are sharpened knuckledusters) or as cash (the richest man I know is a market trader who wears heavy bracelets, necklaces and a diamond-set watch "so I can keep my money where I can see it" rather than be swindled by banks).

Anyway apropos the original question, google "Roentgen's wife" to see the earliest anatomical x-ray, with a massive gold ring on her finger. Of all the common metals, it has the highest x-ray attenuation factor!
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: chris on 19/08/2016 11:33:03
Bizarrely, the sequence of numbers 49 - FIVE - 821 in Alan's message is triggering the blacklist!
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: chris on 19/08/2016 11:34:57
Alan - what is the dose from your x-ray machine? Might people object to being blanket scanned at airports on the grounds of ionising radiation exposure?
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 19/08/2016 11:56:39
The design criterion is 0.1 microsievert per scan. This is set so that aircrew (who may undergo 2000 scans per year) do not add significantly to their unavoidable occupational exposure of 4 millisievert per year (more for Concorde and regular polar crew).

It's about the same as one hour's natural background dose in Aberdeen airport, 90 minutes in Newquay, or 15 minutes in Riyadh or Boulder, Co. Of course I wouldn't compel anyone to use my machine when they can have a 15 minute homosexual body search instead. But nobody takes airline "security" seriously anyway - see my previous posts in this thread - or they would have full-body x-ray scanners at every gate, like we supply to diamond mines.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: evan_au on 19/08/2016 11:58:23
Quote from: A A KAREEM
   If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray scanner?
You don't need to do anything to block the X ray scanner - gold does that all by itself.
That's what makes it so easy to spot.
And looks suspicious, because it looks like it is hiding something that you don't want to show up on the X ray machine.

Alan had the best idea - turn it into bling, and flaunt it! And travel First Class!
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: evan_au on 19/08/2016 12:03:46
Quote from: alancalverd
diamond mines
I know that diamonds fluoresce under X-rays. But does that absorb enough energy to attenuate the beam significantly?
After all, humans have a lot of carbon too - but even more water.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 19/08/2016 17:48:21
At high x-ray energy, most biological materials have pretty much the same mass absorption coefficient. Diamond, however, has about 3.2 times the density of human soft tissue - almost the same as bone - so shows up quite well in a 250-kV x-ray of a human body. It also helps to know where to look.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: syhprum on 19/08/2016 22:07:45
What is the effect on the diamond miners of all these X Rays ?, are they expendable ?
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: evan_au on 19/08/2016 23:25:00
Quote
are diamond miners expendable ?
I have visited the Diamond Museum in Antwerp (Belgium), where they show a lot of the history of diamond mining.
Unfortunately, during much of that time, it seems that the native population has been considered a consumable. [:(]
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 19/08/2016 23:52:25
What is the effect on the diamond miners of all these X Rays ?, are they expendable ?

See reply # 15 above. The unit I work with runs at about one twentieth of the dose of some of the competition.
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: chris on 22/08/2016 21:00:24
At high x-ray energy, most biological materials have pretty much the same mass absorption coefficient. Diamond, however, has about 3.2 times the density of human soft tissue - almost the same as bone - so shows up quite well in a 250-kV x-ray of a human body. It also helps to know where to look.

Where's the preferred site then?
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: alancalverd on 22/08/2016 23:51:08
Topologically, the human being is a torus, so whether you swallow the contraband or shove it up your backside makes very little difference to the maths, and not a lot to the radiological physics. In a single anterio-posterior projection we might have some difficulty distinguishing a diamond lodged in the pelvic region but it would show up in the lateral projection.

Your best bet is "hiding in plain sight". Empty the lead shot from a cartridge, refill with Gauge 1 rock ballast, shoot yourself in the belly, try not to bleed to death, and wait for the scars to heal over the pebbles.  Or acquire some hepatic granulomas (toxoplasmosis works well, but takes even longer than shrapnel). Chances are that a small diamond would look like stone shrapnel or a focal calcification of the liver, to the untrained eye*. Now filter your poo for a day or so, and who knows, you might have a couple of dollars' worth of industrial cutting diamonds!

However given that the best kimberlite yields aound 0.5 parts per million of diamond, you will have  to swallow an awful lot of Africa to be certain of bringing  home anything worthwhile.

*we include a training package and some basic radiological anatomy with the kit
Title: Re: Would a gold bar be visible to aircraft security scanners? How can I obscure it?
Post by: JimBob on 26/08/2016 03:36:25
Chris,

You don't have that much money!
Title: Re: If I want to take gold bar or rod concealed in my bag to the airport, how to block baggage xray
Post by: William McC on 26/08/2016 05:48:01
Why bother? It is not a prohibited substance.

Can you mold them into man made plasticized stone and call them drink coasters?

Sincerely,

William McCormick