Say there's a massive explosion in a building, like if a bomb goes off next to someone. Entire floors of the building are leveled. What happens to the human body that was nearby, assuming average size?
Is it completely incinerated? Are there body parts to recognize for forensic evidence? Could someone just walk up to the scene and figure out who had died? Scientifically, how does this work?
Typical Hollywood explosions are gasoline based and for the most part only result in a fire ball. If you’re caught in the fireball you’re going to get surface burns but not incinerated as the burn isn’t nearly hot enough or long enough. Translations charred body lots of forensic evidence.
Assuming real explosives (say a grenade or something) the actual explosion is much smaller and faster (much less burn much more force). If you’re in the blast radius you’re basically going to get torn to shreds. Assuming you’re outside the blast radius and just in the area there are two main factors to consider 1) shrapnel everything in the blast radius that isnt nailed down basically becomes a bullet (this is how grenades do most of their damage) and 2) the shockwave.
High explosives on the other hand cause a rapidly expanding pressure front that creates a shockwave. Humans being basically sacks of water don’t do well in there to close to the wave.
For real world examples I recommend watching myth buster’s seasons 4 they blew up a lot of things with a lot of different type of explosives that season. Hope that helps.
The primary factor is whether the volatile substance is incendiary or explosive in nature.
If it's gasoline it's be mostly fire with very little concussive force, so the baddies would just get surface burns or catch fire themselves and maybe be completely incinerated if it's strong enough (but the hero'd be crispy too, if that's the case :weird:).
If the substance is explosive in nature (TNT style) there would be significant concussive force and little fire, so the baddies would be subject to large forces mostly, with heat being a secondary concern. Depending on the size of the explosion, they'd end up from just pushed over to as if a train hit them to nothing but kibble bits if it's strong enough (though again, hero'd be kibble bits too).
Picc's got the right idea, youtube explosions and mythbusters stuff to get a better idea of it all.