Schneier on Security
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November 21, 2008
Friday Squid Blogging: Preserving Giant Squid
At the Smithsonian:
At the centerof the Smithsonian Institution's National Museum of Natural History's gleaming new Sant Ocean Hall lies a preserved giant female squid -- the arresting, spineless star among the vibrant exhibition's animal specimens. Tentacles menacingly outstretched and seemingly frozen in time, the 24-foot squid embodies humans' fascination with the briny deep. But this squid also symbolizes something else: an ongoing experiment in the chemistry of preservation, without which the Smithsonian's new exhibition would not have been possible.
Also note the terrorism tie-in:
To create the exhibit, the Smithsonian had to work around post-9/11 rules restricting flammable materials, while maximizing the lifelike appearance of the squid for public display. They turned not to formalin or ethanol, but to a new fluorinated chemical called Novec, developed by 3M.
If we give up our preserved giant squids, then surely the terrorists have won.
Posted on November 21, 2008 at 4:20 PM
• 16 Comments
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Nice, Bruce. You managed to find squids and terrorism in the same article. I'm impressed ;)
"If we give up our preserved giant squids, then surely the terrorists have won."
I weep for our once great land that has become a place where such a statement makes way too much sense.
Your prescience including squids in discussions of security has been remarkable.
Those who would give up Giant Squids to purchase a little Fire Safety, deserve neither Squids nor Safety.
Actually given the low boiling point of Novec and it's fire suppression properties a movie plot terrorist would use an incendiary explosive to vaporize the fluid and asphyxiate the people in the hall.
But... Why squids every friday?
It frankly does not seem unreasonable to suggest that if a display containing 10,000 gallons of liquid be separated from the public by a thin transparent barrier, then that liquid should be neither highly flammable nor carcinogenic. If it really took 9/11 to promulgate such a rule (which I frankly doubt), then thank goodness for 9/11 injecting a note of common sense for a change, instead of being an excuse to conceal foolishness.
> Actually given the low boiling point of Novec and it's fire suppression properties a movie plot terrorist would use an incendiary explosive to vaporize the fluid and asphyxiate the people in the hall.
a) Since Novec seems to be almost completely non-toxic, this would require that so much of the material evaporate as to completely exclude oxygen, for long enough to cause asphyxia. This is very unlikely because
b) It's not *that* volatile; the boiling point is 49°C, so it would take immense energy to vapourise a large amount quickly. In fact it will not be all that much different to releasing an immense amount of water, just evaporating somewhat faster, and reaching a somewhat higher equilibrium "humidity." The idea that the terrorist's device could boil off enough to cause asphyxiation is not much more plausible than suggesting that they could asphyxiate people by boiling off a large amount of water. Of course once released, it will all evaporate eventually, but there will be plenty of time to get some ventilation going.
"Actually given the low boiling point of Novec and it's fire suppression properties a movie plot terrorist would use an incendiary explosive to vaporize the fluid and asphyxiate the people in the hall."
Maybe this year's movie plot threat contest should involve giant squid in some way.
Dear Mr. Schneier,
As an Information Security analyst, I follow your blogs regularly, and I found it particularly remarkable as to how you tied a story related to Squids with national security...
... your perspectives are very refreshing and welcome indeed - many thanks!
"a) Since Novec seems to be almost completely non-toxic, this would require that so much of the material evaporate as to completely exclude oxygen, for long enough to cause asphyxia. This is very unlikely ..."
Hmm not sure on that, Halon is non toxic, and in vapour form heaver than air. However a number of people were killed by it.
It got into their lungs and was difficult to cough out, the either passed out or dropped to the floor where they got further halon in their lungs displacing all oxygen at which point their fate was sealed unless rescued by people who knew what to do (just giving oxygen often did not help).
One of the only reasons inhaling "condensing" water vapour (ie fog/mist) does not kill you is that your lungs are lined with it and it quickly condenses out whilst still alowing oxygen to cross over.
Even lighter than air gasses such as hydrogen, helium, methane etc will kill you by asphixiation. Often faster than they will poison you if they are toxic.
There are toxic gassess that will kill you fairly rapidly (anyone for rotten egg stink bombs) but this is usually due to their fatal concentration being measured in parts per million or even billion and having a catalitic or nurological inhibitory toxicity (anyone for bitter almonds or VX).
It's been many years (1/4 C) since I had to "know this stuff for my own safety" so I'm a bit rusty on the details these days 8(
Yes, asphyxiation by displacement of oxygen is possible for any gas or gas mixture (other than one containing adequate oxygen), if it is present at a high enough concentration that the residual oxygen concentration is too low to support life.
This is true of nitrogen, Novec, and the halons. The difference between Novec and halons (any halon, but especially 1211 or 1301) is that Novec is much less volatile. Those halons have boiling points below room temperature, so at equilibrium they can (under the right circumstances) completely displace all air. Novec has a boiling point of 49°C, so at typically room temperatures, even under pessimal ventilation conditions there will still be some air left. Exactly how much depends on the vapour pressure curve, the exact temperature, and just how bad the ventilation is; but it seems pretty unlikely that it will build up to asphyxiating concentrations.
> One of the only reasons inhaling "condensing" water vapour (ie fog/mist) does not kill you is that your lungs are lined with it and it quickly condenses out whilst still alowing oxygen to cross over
Sort of; the key point is that the boiling point of water is much higher than either typical ambient temperatures, or body temperature. Thus it cannot normally be present at concentrations high enough to exclude sufficient oxygen to cause asphyxiation; if it does reach such a high concentration (e.g. by being pre-heated), then the excess will, as you say, condense out. But this is just as true for Novec, with the difference that the STP / b.p. difference is not as large, so it can get somewhat closer.
(Having said that, at sufficiently reduced air pressures, such as the tops of the highest mountains where the boiling point of water approaches human body temperature, it would be possible to asphyxiate someone with water vapour.)
@ roger and clive,
i hope you don't mind me reading your posts in the voice of "comic book guy" of the simpsons. :)
"i hope you don't mind me reading your posts in the voice of "comic book guy" of the simpsons. :)"
If that displaces an equivalent mass of water as your aquatic craft 8)
That's good news for medical students, anatomists and forensic pathologists everywhere: an alternative to formalin/formaldehyde!
Off topic, but security related. The chrome browser has gotten me so used to typing search queries into the address bar that when I was trying to find out more information about this "bbetter.ru" spam* I had hit enter before I realised I was actually going to visit the website. Hit escape madly, but at least some of the page had loaded already.
Serves well to hit home the tradeoff between convenience and security (Is combining the search and address bar actually more convenient? Yesterday I thought yes)
(* I was mostly curious if it was trying to install malware or just selling something)
What's your problem with all these anti-chemical laws?
Remember... we can't be too careful, since the tentacles of Al-Qaeda reach all around the world.
So don't be a sucker. When Mike Chertoff says "jump", say "how high".
(sorry... I couldn't resist).
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