So, I was researching about shockwaves and things that can kill you, and after a some time, I found several infos but this is where the info is more detailed. Here show me how I can scale explotion and differents kinds of explosives that maybe could be useful for the wikia.
Types of Explosive[]
Maybe this isn't used so often here, but there is always an especial case; from the link from above, exist the equation We= W*(H/Htnt), where We= weights in tnt (kg), W= weights of the actual explosive (kg), H= explosive heat of detonation, and Htnt= TNT heat detonation. Using the table from the right (found it in from the link from above too), I got that 1 kg of:
- C4= Pentolite 50/50= 1.4005 kg of TNT
- RDX= 1.3527= 1.3527 kg of TNT (used the average value, 5.66)
- PETN= 1.5989 kg of TNT
- Nitroglycerine= 1.5057 kg of TNT
- Nitrometane= 1.5296 kg of TNT
- Nitrocellulose= 2.5334 kg of TNT
- Amon/Nit= 0.38 kg of TNT
The most common is that we use the TNT values especially since I barely know about half of those explosives, but when the explosive is mentioned (common in TV series and action movies), is better use this values.
Scaling TNT[]
When a character is caught in one explosion, we generally scale the image and we use this calculator to find the yield and directly scale it to the character's Durability. But there is another factor and is the distance from the character to the explosion origin; as far is the character from the explosion origin, weaker is the shockwave, so again from the link above, the formula fro the overpressure (explosion shockwave) is: P= 6784*W/R^3+93*sqr[W/R^3], where P= overpressure in bar, W= weights in tons of tnt, and R= distance from the origin in meters.
When the distance from the explosion is significally notable,what we should do is:
- With the radious from the explosion R1 and the yield W1, we find the overpressure P. When we scale, the pressure and speed doesn't change.
- From the equation above, the TNT weights (tons) is: W2^2-R2^3(2.9481*10^(-4)*P+1,8792*10^(-4))*W2+2.1728*10^(-8)*P^2*R2^6= 0, yeah, was a mess found the equation, but I checked it and does work; this time, R2 is the distance from a black-point explosion, we'll use 1 meter, and that simplifies the equation.
- Almost "finishing", we'll find something like W2^2+A*W2+B=0, don't be afraid, we can use this calculator or another similar. Notice that we get two result, but the correct one is with the - (not sure why, but checked several times)
- With that we got the new TNT value for a black-point explosion.
In order to check, I'm going with one example: a guy that tanked an explosion of 200 TNT tons from a distance of 300 m. First step, we use the equation P= 6784*W1/R1^3+93*sqr[W1/R1^3], placing the values, P= 0.3033 Bars.
Second step, we use the equation W2^2-R2^3(2.9481*10^(-4)*P+1,8792*10^(-4))*W2+2.1728*10^(-8)*P^2*R2^6= 0, placing the P and the new R2= 1 meter, simplifying the equation I got W2^2-2.7733*10^(-4)*W2+1.9987*10^(-9)= 0; now with the thirst step, I use this and the result (the one with -) is 7.4046*10^(-6) TNT tons.
In short, a guy tanking an explosion of 200 TNT tons from 300 meters is the same that a guy tanking an explosion of 7.4046 TNT gr from one meter.
NOTE: The formula only applies to explosions in the ground, in a more or less smooth surface, and the building arounds aren't significally big; futhermore, the durability that could be calculed from this only cover the explosion itself (shockwave, fire), splinters nor flying fragments aren't taking into account.
Explosions that can kill you[]
This part is just for reference, this document show us what overpressure is able to spawn-kill, kill, damage or scratch us; I'll try to make my own classification, but feel free to fix it:
- >=20 PSI: Imminent Death (C20)
- 10 PSI: Highly Lethal Injuries, death is most likely (C10)
- 5 PSI: Lethal Injuries (C5)
- 3 PSI: Serious Injuries (CIII)
- 2 PSI: Light Injuries (CII)
- 1 PSI: Minor Injuries (CI)
- <1 PSI: Unaltered (C0)
Use the pic from above for reference, where the Axis Y is Weight in tons and the X is distance in meters; about the color: Red to the left is C20, blue-red is C10, green-blue is C5, purple-green is CIII, yellow-purple is CII, black-yellow is CI and black to right is C0.
Using the example from above, that guy just received Serious Injuries (according to my clasification): despite being and 9-B explosion, an human is able to survive from a black-point explosion, with serious injuries tho. Actually, an average adult human is able to survive that kind of explosions, so, just for reference, I made a "table" for the amount of TNT gr that a human can tank:
- C20: Explosive >= 80.289 gr.
- C10: 80.289 gr > Explosive >= 28.471 gr.
- C5: 28.471 gr > Explosive >= 9.2105 gr.
- CIII: 9.2105 gr > Explosive >= 3.7914 gr.
- CII: 3.7914 gr > Explosive >= 1.8198 gr.
- CI: 1.8198 gr > Explosive >= 0.4965 gr.
- C0: 0.4965 gr > Explosive.
So, if a character after tanked the explosion possesses the same injuries and shows the same tiredness than an average human, the feat itself isn't impressive; if the the character is unharmed or with less injuries than an average human should have, so that character is superhuman and the TNT amount should scale to Durability/Stamina; and if the character possesses the same injuries but isn't tired or but can still fighting, so that should scale to Stamina. Remember that the character is 1 meter from the explosive, not just above it, the 1 meter were used cuz is the minal unit for the equation, below 1 meter, the result become inconsistent.
However, those values are in areas surrounded by building, were the reflected pressure and collapsing walls/splinter is what kill the people; normally, is needed at least 55 PSI to kill a human (from the same document), that is the equivalent of a peak overpressure of 315.5 kg of TNT at black-point (without counting the fire, of couse).
welp, any thoughs or suggestions? If there already numbers for the calification/better names, I'm open to change it.