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March 26, 2009
Surviving a Suicide Bombing
Where you stand matters:
The two researchers have developed accurate physics-based models of a suicide bombing attack, including casualty levels and explosive composition. Their work also describes human shields available in the crowd with partial and full coverage in both two- and three-dimensional environments.
Their virtual simulation tool assesses the impact of crowd formation patterns and their densities on the magnitude of injury and number of casualties of a suicide bombing attack. For a typical attack, the writers suggest that they can reduce the number of fatalities by 12 percent and the number of injuries by 7 percent if their recommendations are followed.
Simulation results were compared and validated by real-life incidents in Iraq. Line-of-sight with the attacker, rushing toward the exit and stampede were found to be the victims' most lethal choices both during and after the attack.
Presumably they also discovered where the attacker should stand to be as lethal as possible, but there's no indication that they published those results.
Posted on March 26, 2009 at 8:08 AM
• 31 Comments
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Is it just me?
If I knew in advance that somebody in a crowd was a suicide bomber-to-be, then I don't think I'd be working out where the best place to stand was, relative to them. I'd be getting the hell out of there.
By the time you've discovered they're about to go pop, you are where you are.
That bit should be obvious to any suicide bomber - you should jump as high as possible right at the point of explosion, as airbursts are the most effective means.
At the very least, jump so high that your explosives are higher than head-height.
If in doubt, jump from a high building before detonation - however, do take note of the length of your fuse or all you'll leave is an impressive crater.
I wear my safety belts whenever I drive. The strategy of recognizing that I'm about to crash, and then putting on the belts, would likely be ineffective.
Perhaps these researchers are proposing patterns that people could follow habitually, to increase their odds of surviving such an attack.
Infantry have been trained for a very long time, when walking on patrol (at least in certain environments), to stay spread out -- if the soldiers cluster together (instinctive when scared), they make an easier ambush target.
More importantly, it might be possible to engineer lines and public spaces to naturally spread people out in the right way to minimize casualties. Architects can direct people pretty well if they think about it ahead of time, and have a goal.
I could not imagine there is a whole lot of time for decision making.
This is what I will call pure junk (and no science).
Why would Bruce give credence to such non-sense is beyond me.
It's probably funded with some us money (directly or indirectly) .. and other than making some worthless researchers secure in their tenure - it would nothing to make anyone else more secure.
Why is this specific to suicide bombings? I would expect these results to apply in any situation where an explosive detonates in a large crowd, whether initiated on the spot by a suicide bomber or remotely by cell-phone.
@ Vaguely baffled,
"By the time you've discovered they're about to go pop, you are where you are."
You are not thinking it through fully.
Apart from the reason MarkH gave. In some cases a sucide bomber is suspected in advance of the act.
If that is the case the LEO's can when the authorities tell them to "pull the plug" on the suspect. On the valid assumption that sucide bombers will use a "dead man's switch" the bomb will explode, and probably (if a thumb or mecury tilt switch) before the bomber falls over.
If the LEO's know the likley blast patern they can chose a time when the casualty count can be lower, before despatching the bomber of to where ever they belive they are going...
"Presumably they also discovered where the attacker should stand to be as lethal as possible"
Part of which is self evident from what they have published as for other positions (like standing in 45degree line in corner) any simple book on physics will give you the answers.
As for jumping up in the air, unless the bomber is a top flight gymnast they are actually likley to reduce the blast radius due to the upper torso being larger and more shock absorbant.
A little early on the April Fools posts there, eh?
"This is what I will call pure junk (and no science)."
Without actually seeing the science that's a little premature, don't you think? Regrettably this sort of thing bears careful study. Careful analysis of suicide bombings should provide insight into attacker behaviour, target selection, device effectiveness, and crowd dynamics. The physics should be just one element of such studies though.
All that said, I like Vaguely Baffled's solution: It's best to be standing several miles away from the bomber when he (or much less frequently, she) presses the byebye button.
You beat me to it.
"Springboards of mass destruction"
Where you are in relation to a bomb affects your survival chances?
We already layout buildings to make fire evacuation easier. Retailers often layout their stores to allow staff to watch for shoplifters. If this is a major threat where you live, then it makes sense to layout markets and other places people congregate to minimize the potential damage. In the U.S. it would probably not be useful because fire, stampede, theft and probably a dozen other things are more likely to occur here. In Iraq the situation may be that attacks like this are the a common enough threat that it does make sense to consider these sorts of findings in the design of places people congregate.
It's the Bomb Kata!
When does the video game come out?
Forget springboards, trampolines are more fun!
> Presumably they also discovered where the attacker should
> stand to be as lethal as possible, but there's no indication that
> they published those results.
I bet you can reverse engineer it from their results...
I wonder if they discovered any altruistic patterns by which a small group could guarantee their own deaths while greatly increasing the expected number of survivors. I think they'd have difficulty getting those recommendations put to practice.
@Ricky: Sure there's time for decision making. You make the decision by not standing in a dangerous spot in the first place.
I don't mean this facetiously -- this sort of thing has been common knowledge for a very long time in places like Israel, where suicide bombings are a known hazard. People get fairly good at casing a joint the way that a bomber would, and knowing where not to be. (e.g., don't hang around next to large plate-glass windows in unsecured areas)
While engineering studies like this are very interesting, I think that an even more interesting approach may be an ethnological one -- research into the rules of thumb which people routinely exposed to a threat develop.
"I wonder if they discovered any altruistic patterns by which a small group could guarantee their own deaths while greatly increasing the expected number of survivors."
Hmmn, I'm not so interested in guaranteed death but I'll hold one end of the bomb blanket if you promise to hold the other.
I suppose it's worth calculating if (by inverting the "thinking" of our trampoline/springboard enthusiasts) getting the bomb/bomber on the ground would help. The overpressure wave is still an issue for those within its lethal radius but something like half of the shrapnel goes into the ground and a fraction of it is directed upward (or, if you're the tackle, into you). Of course the bomber then becomes large chunks of shrapnel on the horizontal axis instead of the vertical.
Yup, still better to be at home in the shower when the bus stop goes boom.
"Of course the bomber then becomes large chunks of shrapnel on the horizontal axis instead of the vertical."
And that's a problem...
If you think about where a suicide bomber carries their bomb (lower torso around waist to aid hiding it).
When it explodes in a crowd most of the shrapnel that will harm you will go into those immediatly around the bomber the rest upwards or downwards either way if there are two or more people directly between you and the bomber then direct shrapnel is not going to be much of an issue for you (I'm ignoring indirect shrapnel and the overpreasure wave for now).
However if the bomber is on the ground then it's just peoples legs to stop the direct shrapnel and it will actually go further and probably hurt more people (it is also likley to pickup more indirect shrapnel as well).
That said even in a dispersed crowd a suitable hight will be of benifit to the bomber (say 5-10 people high). As the angle of incidence will pick up more indirect shrapnel whilst also giving a better "people coverage" of the over preasure wave.
However the above is just a thought excersise first aproximatiom. You would need to actualy get a realistic simulation to get a valid answer...
I'm no bomb expert, but going on the tackling/springboard deal, it seems like tackling should work.
I would expect bomb manufacturers to be getting relatively good at their job (we've been fragging people for centures). I would expect the bomb to be designed to minimize vertical shrapnel. An ideal "crowd cutting" bomb would just expand in a ring.
Thus, if they had a well designed bomb, you might be able to do some good by getting the bomber horizontal (i.e. on the ground). Then, instead of a ring, they simply draw a line plus shoot a lot of shrapnel into the air where things like terminal velocity can play a part.
That failing, you could always try to convince him to hula-hoop in those last few moments. Not as effective, but if you can get him to really move those hips...
I am reminded of the "Unclear on the Concept" cartoon of the schoolteacher with her class huddled around her and saying "Very good class, and where would you stand if a nuclear warhead were to land over _there_?"
I also am serious .. I have put a biz plan together to develop an application that you can install on iphone.
It will advise you
a) when suicide bomber is in the vicinity
b) will calculate for you in which direction to run "AFTER" the bomb has exploded
c) you pay only $9.99 for it -- will offer money back guarantee if you don't survive the attack
Serious science .. my foot -- I have CDS's that some serious scientists designed that I can't seem to figure out ... no one can.
I suppose the number-one takeaway from all this, if you want to survive a suicide bombing, is “Don’t be Benazir Bhutto”.
Actually Benazir survived the bomb blast that killed about 200 people "around" her - she had just gone in the truck to take a nap.
What killed her a few months later was a bullet, or a bang on the head, as her government would have you believe.
I would sure like to see the conclusion from a federally funded study that theoretically proves that to survive you shouldn't stick your head out when people are trying to shoot at you.
My grandfather was taught this in the army, so it's been known for at least 65 years. As he put it: "If you ever think there's about to be an explosion, the best thing you can do is hit the ground. Forget about running."
Duck and Cover, was a good idea. Avoid the flash, not look at it. Also it is "fun" to laugh at the propaganda of the duck and cover world.
This research simulation, is also a good idea.
Little things make a big difference.
I'm glad that some are working to handle and make bad scenarios better, rather than just cheap laughs.
I had a chance to attend the presentation of this research recently at Nashville, TN during an IEEE conference. The actual paper is available at http://my.fit.edu/~zusmani/Virtual.pdf
What I learned from the presentation is that this tool can be used for forensics investigation. you can give the tool the number of dead, injured and little description of scenario and tool can predict with +-4% of error margin that what happened, how many bombers were there, how many people were there, where they were standing etc
It is a cool tool and most importantly this is supposed to be the first tool with real human data. Most of the models we have been using in risk assesement for last 6 decades are based on sheeps and pigs or sensors assesement without any real life behavior. if you are interested, have a look at current models like kingrey-bulmash, harold Brode, Paul cooper, Henrych Smith etc
What I am concerned about this research is that it can be landed in the hand of bad guys and by using the same tool, they can find where to hit?
Hm, this simulation is probably interesting for terrorist too, they can calculate bet position to stand when activate bomb...
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