Blast injuries are more common than we take account of. They can come from multiple different reasons, not just a bomb, but also in house fires, in-cylinder fires, where anything explodes, creating a vacuum and a shock wave. What we need to look at is how far away, what was involved, and how severe the blast wave itself was, because we got a primary, a secondary and a tertiary wave in a blast. If we get an explosion, if you go out on bonfire night and people are lighting fireworks off, you can feel the blast wave as the explosion happens from the firework. We’re talking now about explosions that are much closer and much greater than fireworks.
So the first thing that affects anybody will be the blast wave itself because as the explosion goes off, it sends a wave out from the centre or from the epicentre. That wave can be severe enough to rupture eardrums, livers, kidneys. It can do severe damage to your lungs because of that massive, very rapid pressure wave travelling across the surface of the ground. And that actually can be big enough to be fatal on a lot of occasions if we’re talking about large bombs and large explosions.
The next thing we get is the secondary wave. The secondary wave tends to be all of the rubble, the shrapnel, the metal, the particles that that blast wave throws out from the epicentre. So you get hit with the first wave, the shock wave, the second wave, debris fragments, which will come flying through the air, sometimes 1000 miles an hour and will hit you at full speed.
And thirdly, you get the tertiary shock wave. The tertiary shockwave comes from behind you. So two waves hit you from in front as the blast wave leaves the epicentre. But when it leaves the epicentre, it creates a vacuum, and that vacuum has to be filled. So air and particles rush back in to fill up the vacuum at high speed and again can do damage to the liver, lungs in particular. Because again, it is a massive rapid change in air pressure. And we can get things like the paper bag effect, where the lungs burst due to overpressure, or we can actually get the lungs drained of oxygen being sucked at due to the vacuum. And that’s where you get the mushroom cloud from an explosion as all the particles rush back to the centre, and then go up into the air in a tube and then cascade over the top of the tube like a mushroom.
So we get primary, secondary, and tertiary waves. Those in themselves, each separate one can be enough to kill you but put them all together and it puts the body through a massive amount of trauma, which can do damage to all your internal organs, your eyesight, your hearing, your ears, your lungs and can be very, very difficult to manage, because we have multiple damages to multiple organs. And depending on how close you were to the blast, the damage obviously is going to be greater to people closest to the epicentre than the further you are away. But these epicentres and blast sizes can be great enough to do damage in two or three miles distance if there’s nothing there to protect us.