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Comment by cwal37 | Hacker News Reader

For some reason people have this idea that LNG tankers are a big bomb waiting to go up, but that's not really true. Vapor cloud detonation has never been considered particularly likely, and never documented as far as I know. Mostly it seems the vapors that hit the right mix of oxygen and such would burn pretty rapidly, while the warmer gas began to rise. It would certainly be a large fire for a while, but shouldn't have the lasting impact of an oil spill. Here's a paper[1].

[1] http://www.mhpa.co.uk/uploads/Marine_docs/lng_carriers.pdf

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The scary bit for LNG is a BLEVE (Boiling liquid expanding vapor explosion). Even non-flammable liquids undergoing a BLEVE can be incredibly destructive, for example: https://www.youtube.com/watch?v=fgdfgxLApL4

So it's nothing to do with vapor cloud detonation, that's pretty much irrelevant compared to the destruction of the rapid phase transition from liquid to gas.

I think a tanker ship is pretty safe from a BLEVE. Those explosions usually result from a tank being heated continuously by a very hot fire underneath it. I'm not sure where you would find one of those at sea unless the tanker wrecked on top of an erupting volcano.

And there's my entry for Bruce Schneier's next movie-plot threat contest...

As safe as nuclear power!

Nuclear is incredibly safe

Of course it is! It comprises two of the safest things in the world, radioactive materials and fission! That's never been a recipe for disaster!

If you are suggesting that a nuclear power plant can detonate like a nuclear bomb, you are wrong, they are a completely different design. Sure they can melt down in rare cases, but that's hardly anything on the scale of a nuke. I would suggest you look at some of the stats for death rates of different power sources. Nuclear is near the bottom, coal kills thousands every year through air pollution. If you want to find a truly dangerous power source, look at hydroelectric, when a dam collapses it is more damaging than a power plant meltdown in some cases.

Safer than some of the alternatives != safe.

So why aren't you panicking over dangerousness of wind turbines? This is pretty bad argument.

If only it were not for those meddling humans, he would have got away with it!

How many tankers would you need to noticeably change the explosion power of an average sized volcano eruption?

How about an LNG bunkering facility in Naples, near the Campi Flegrei volcano?

Maybe you start with a minor eruption/earthquake, and the LNG disaster breaches a larger magma chamber to cause a larger eruption? Then you can blanket Europe in ash and start up the typical disaster movie plot, where you follow the Chicken Little and their family as they try to escape the disaster radius.

Is an LNG tanker safe from a bad guy on a fishing boat?

https://youtu.be/C3p96VNXSNQ?t=22

I wonder how thoroughly the various failure scenarios have been modeled and reported on. Something merely of the magnitude of the East Ohio Gas Fire [1] in a crowded port or canal would be awful, and I'm pretty sure a supertanker carries a lot more gas.

[1] https://en.wikipedia.org/wiki/Cleveland_East_Ohio_Gas_explos...

The industry has every incentive to do a careful job with the safety features of these ships and the terminals they unload into, but the trouble with ships is that things sometimes run into them... sometimes really big things.

It's a pretty awesome way to carry around a lot of portable energy, though.

> never documented as far as I know

It happened in Brenham, Texas, in the 90s.

http://www.theeagle.com/blogs/fajitas_for_one/salt-dome-expl...

That was a salt dome holding area, and not a tanker, to be fair.. but yes, it exploded. People in houston (~45m-1h drive away) felt the rumble and thought it was an earthquake..

From your original post:

> Vapor cloud detonation has never been considered particularly likely, and never documented as far as I know

This is an example of a vapor cloud detonation. I'm just pointing out that it's happened, so I'm not sure why you're saying it's never been documented. Unless you just meant in the context of a tanker, but that's not how you phrased it.

As it happened, I lived in the area at the time (about 40 miles away on the back side of Cypress, Texas). I didn't think so much about it being an earthquake, but instead thought a large airplane had crashed nearby. I ran out into the street expecting to see fire and explosions and whatnot within a block or few of my house ... only for there to be _nothing._

Not the same person...

x2. Explosives that used ambient oxygen to burn the fuel need to be finely tuned. Blowing up a propane tank (regardless of size) gets you a big fireball.

I find the fear of flammable gasses to be irrationally excessive. Sure there's more stored potential energy than the batteries under the floor of your Prius or the smartphone in your pocket but by nature of being compressed the storage tank is very robust and unlike batteries they do not include their own ignition source.

They made fun of this, I believe, in 21 Jump Street (the remake).

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