How does a blast wave kill you?

[raketenjagdpanzer]

A friend of a friend was in an MRAP that hit a mine on Route Irish outside of Baghdad. No injuries, nothing. Started having serious emotional problems that were ascribed to PTSD, so they gave him a fistful of xanax to take on a daily basis and a desk job (still in country) and he was still having issues. Got rotated home, VA kept sending him for "talking therapy" and more and more and stronger and stronger antidepressants until finally he went to a civilian hospital and got the full MRI the VA insisted he didn't need and found out lo and behold his pineal gland had gotten detached. It was still there and still connected but it had been pushed around and damaged while nothing else in his skull had been. Left him prone to fits of rage, impotent...just a fucking mess.

So...that's how. Just another mm or so of movement would've left him dead.

[TrailerParkJawa]

Originally Posted by raketenjagdpanzer

A friend of a friend was in an MRAP that hit a mine on Route Irish outside of Baghdad. No injuries, nothing. Started having serious emotional problems that were ascribed to PTSD, so they gave him a fistful of xanax to take on a daily basis and a desk job (still in country) and he was still having issues. Got rotated home, VA kept sending him for "talking therapy" and more and more and stronger and stronger antidepressants until finally he went to a civilian hospital and got the full MRI the VA insisted he didn't need and found out lo and behold his pineal gland had gotten detached. It was still there and still connected but it had been pushed around and damaged while nothing else in his skull had been. Left him prone to fits of rage, impotent...just a fucking mess.

So...that's how. Just another mm or so of movement would've left him dead.

I think it's sad that he didn't get the proper care or check up he needed from the VA.

[Targan]

I was a little bit too close to a few explosions back when I was a shotfirer (aka powder monkey). I know exactly what Grimace says about the "funny feeling" you get in your chest. I suspect he's talking about an explosion that occurred near him in actual combat, and I'll wager that he was somewhat closer to his explosions than I was to mine.

During my explosives training we let off a couple of fairly big ANFO explosions that were detonated virtually on the surface on flat, dirt ground. Mainly to show us what a bigger explosion looks and feels like. Upwards of 50 or 60 kilos, with a half a dozen sticks of Powergel to ensure a good initial detonation (I've seen much more ANFO go up but only with delayed detonations, the individual charges were smaller). We were crouched behind a low berm probably half a football field distant and you could clearly see the shock wave spread out from the epicentre. You feel the "crumph" right through your body. The first couple of times it creeps you out.

[WallShadow]

Originally Posted by Targan

---snip---You feel the "crumph" right through your body. The first couple of times it creeps you out.

Like being in close proximity to a bunch of bagpipers, only much less damaging!
NOTE: I really do love the pipes, but I couldn't resist the free shot.

[Medic]

As one of the resident medics, I believe, I could clarify the effects of pressure waves on people.

Now, explosion is a sudden, rapid combustion. It causes heat and a shockwave, both of which have potential to kill.

Heat causes burns and combusts flammable materials. Clothing protects from the worst of it, but if it is not fire resistant, it might combust. Especially synthetic materials often have a nasty tendency to melt when subjected to great heat.

The shockwave is caused by the overpressure, caused by the air expanding due to the explosion. This has several results.

Depending on the force of the explosion, the shockwave sends things flying. The only problem is, it also leaves a vacuum in the ground zero, and should the explosion be powerful enough, the vacuum takes up to a couple of seconds to fill. This means, with bigger explosions, you need to duck not once but twice, as all the stuff that flew off with the shockwave has the nasty tendency of coming back shortly. Best idea is to sit in a foxhole and keep your head down.

Human body has about 60-70% of water and water is a relatively good conductor for a shockwave. While the bones form a rigid case around the lungs, but it isn't enough to stop the shockwave. While the overpressure from the shockwave simply compresses the gases inside the sinuses of the body, the rapid decompression after the shockwave causes the gases to expand so rapidly, the tissues can not compensate. Particularly vulnerable to damage from this kind of decompression is the bowel, filled with fecal matter and gas. It has been documented that people subjected to explosion shockwaves have had extensive damage to their bowels, up to several meters of bowel splitting open inside the abdominal cavity, which leads to a very nasty infection.

Overpressure in turn can cause damage to ears as the tympanic membrane , though flexible, can stand only up to so much. And it is not only the tympanic membranes in the ears that can be damaged. Hearing works through the tympanic membrane moving two very small and delicate bony structures - the hammer and the anvil, both very vulnerable to damage.

Overpressure also causes (usually small) tears in the lung tissue, due to the pressure differences outside and within the thoracic cavity. Lungs are not the only inthe thoracic cavity, that can be damaged. Heart in itself can be damaged by violent external pressure - for an example the F1 driver, Ayrton Senna, died of cardiac contusion after colliding the track wall in high speed.

In a nutshell, if you encounter someone who has been close to an explosion and that person is bleeding from his ears, it is safe to assume that he has a) perforated eardrums and b) perforated bowel until proved otherwise.

A great deal of injuries in explosions are so called secondary injuries that come not from the debris or the explosion itself but falling over or falling from somewhere. As a rule of fist, falling from higher than your own height is considered to be a high energy injuries.

[Michael Lewis]

Wow. I looked up body cavities. There's quite a lot of them.

[Medic]

I believe, if you put that as a search on the internet, you'd get plenty of porn.

Mostly the problem is there if the cavity is either filled with something compressable (bowel) or is in close connection to the outside (ear). Technically opening one's mouth when the shockwave hits might help with the ears, but the bowel - well, just try to keep out of the way of the blast.

[Grimace]

Originally Posted by Targan

I was a little bit too close to a few explosions back when I was a shotfirer (aka powder monkey). I know exactly what Grimace says about the "funny feeling" you get in your chest. I suspect he's talking about an explosion that occurred near him in actual combat, and I'll wager that he was somewhat closer to his explosions than I was to mine.

No, not combat for me. Underground mining and blasting "rounds". Still, the blasts were fairly sizable, and I while I was "technically" at a safe distance, when close to 700 pounds(around 300 kilos)of explosives went off, it still had quite an impressive effect on me. I could only imagine what it would be like being closer to the blast and within range of the flying debris.

[Cpl. Kalkwarf]

Ummm Guys isnt this already taken into effect using the Concussive damage in the rules already.... in an abstract way of coarse.?

[pmulcahy11b]

Originally Posted by Cpl. Kalkwarf

Ummm Guys isnt this already taken into effect using the Concussive damage in the rules already.... in an abstract way of coarse.?

By necessity, T2K (and most other RPGs) oversimplify complex effects to facilitate game play. But yes, that, at its heart, is what causes most of the damage in an explosion: concussion. What's being compressed is air itself, and it can hit someone or something like a freight train. That's concussion. Imagine being slammed against a brick wall suddenly. (Or more like the brick wall being slammed against you.) Another way to look at compression is as overpressure; momentarily, the atmospheric pressure in the shock wave radiating out from the explosion is much higher (depending upon the force of the explosion).

What's worse is that some concussion injuries aren't immediately obvious. It may be weeks or months before someone realizes, "Dale's been acting more and more strange lately."

Here's something not in the rules: Very large explosions, such as from Daisy Cutters or nuclear explosions, can hit you with a concussive blast wave when the air is pushed out from the explosion, and then the air that got displaced suddenly gets sucked back in, fast enough to cause another damaging concussive wave on the way back in!

[Targan]

Originally Posted by Grimace

No, not combat for me. Underground mining and blasting "rounds". Still, the blasts were fairly sizable, and I while I was "technically" at a safe distance, when close to 700 pounds(around 300 kilos)of explosives went off, it still had quite an impressive effect on me. I could only imagine what it would be like being closer to the blast and within range of the flying debris.

Ah, underground blasting. I've never done any of that. To be honest I don't think I'd want to. Those 300kg of explosives must have been in smaller rounds on delay, surely? That's a hell of a blast all in one go. Don't get me wrong, here in Australia on the iron ore mines they let off tonnes of the stuff at a time but it's in a ripple, quarter-second or so delays between lines of blast holes.

[Grimace]

300 kg of explosive put into 36 holes, detonated in a series. 0.1 ms up to 20 ms delay. Det cord was used to set off the blasting caps. So when you were a long distance away you could hear "pwump-pwump-pwump-pwump" in rapid succession. When you were the distance I was, into one big PWUMPF!

[James Langham]

Another injury often forgotten is cranial compression, caused (in this case) by a bleed inside the skull putting pressure on the brain. Signs and symptoms may not show for up to 48 hrs after the impact and it can be fatal (the actress Natasha Richardson is a good example). It is the reason that children bring home notes from school saying they have bumped their head. Treatment is removing a section of the skull to allow the swelling to expand outwards and relieve pressure on the brain.

[Graebarde]

Originally Posted by TrailerParkJawa

I think it's sad that he didn't get the proper care or check up he needed from the VA.

However the VA was the SECOND ones that failed, the military medical facilities should have checked him out too. Wonder how many other PTSD victims are of a similar nature?