Up to one mile "knocks people over". Up to 1.7 miles "kills people".

Huh. It's almost like a bull just shit around here or something.

It's time for everyone's favorite game show: EXAMINE THAT CLAIM!

The subject of the effects of explosions on the human body and the subsequent desire to protect them has been one of interest for decades since the end of World War 2, not only to learn the mechanisms by which bombs effect targets, but how they can be better defended against and what measures of preparedness one should plan for, both to maximize human life expectancy via safety and to ensure infrastructure can (at the least) withstand the effects of explosives.

To this end the Department of Defense spent years developing the Unified Facility Code for the design of all military buildings. Per the UFC, we can know the exact pressure at which certain effects become apparent on the human body. These are tabulated in UFC 340-02 T1-1, and are listed under increasing severity with pressure. 5 psi is the threshold that the average human eardrum may rupture and 15 psi is the pressure at which 50% of individuals exposed to that pressure will experience ear drum rupture. At 30-40 psi, human lungs may be damaged, with 80+ being the 50% exposure. 100-120 psi is the threshold for a pressure wave outright killing someone (via all of the previous effects and some less savory ones that I will leave to your imagination), with 130-180 being 50% fatal, and 200+ being in the 90% fatal range.

Knowing our criteria for pressure, we can then begin to resolve at what distance from a blast will the pressure be at the shockfront of the blastwave. Given the blast location conditions, air-burst, unobstructed ground detonation, etc, we can determine the exact pressure at a given distance for a given bomb size per UFC 340-02 Figure 2-15, which gives the peak incident pressure (Pso [psi]), for a given scaled distance (Z), which is a function of the actual distance (R [ft]), and the explosive charge size (W [lb]). Thusly: Z = R / W^(1/3)

Now we know that the blast charge weight of the MOAB is 18700 lb (which makes the rest of this exercise trival). We don't know exactly what the filling composition is, but it is likely a standard tritonal, PBX, or Comp H6 filling which is typically used in the rest of the military's general purpose bombs. The actual blast material has a variance in TNT equivalency (due to chemistry) which permits them to release more or less energy given their Relative Effectiveness compared to TNT (1.05, 1.6, or 1.35 respectively). For the sake of this evendor we'll assume that H6 is used per this report, and since its midway between the other two. As such that means our effective charge weight is approximately 25245 lb TNT.

For eardrum rupture 5 to 15 psi, we can see from Figure 2-15 that the scaled distance must be 15 to 9. Ergo, for a 19635 lb TNT charge, the distance at which eardrum rupture begins is roughly 440 to 264 ft. Lung damage will occur at 176 to 147 ft, 50% at 111 ft. Lethal threshold is 103 to 95 ft, 50% at 94 to 81 ft, and most everyone within 73 ft will be in less than one piece.

The effect it will have on structures is far a more complex situation involving structural dynamics and requires variables to be defined for the structural system in question, something sadly we lack the time for. However within the aforementioned blast ranges, an adequate estimate can be made from previous experiences, such as the Oklahoma City Bombing of 1995. Most resilient structures can be reasonably expected to fail at a magnitude of 100 psi, and for the MOAB, this pressure range is reached within 103 ft, so most robust structures can be expected to fail at that range. Lesser structures such as wood houses and some poorly constructed masonry buildings can be expected to fail at much lower values and some damaged up to the 3000 foot mark, as the pressure falls to a paltry .3 psi, the rough equivalent of a 130 mph wind. Outside that value, not so much. Some objects might be pushed over, but there certainly won't be too much going down, as pressure waves dissipate exponentially over distance.

Not quite the 1000 yard Hiroshima like conditions expected, let alone killing people at almost 2 miles away.

Almost doesn't sound impressive, until you understand that most bombs rely on shrapnel rather than pressure to inflict casualties. The typical 2000 lb GPB looks something like this when used and that the diminutive effects our heaviest artillery looks even more laughable in comparison.

This begs the question, what kind of shrapnel is it going to throw out?

And my answer is fuck this I'm tired I'm going to bed because it's 2am. I might pick it back up if I feel like it.

Edit: So many spelling mistakes.

I like how "tents" needs to be listed as something that gets affected by this.

I have such a throbbing freedom-boner right now.

You'll only make me want it more, baby

So, don't let ISIS establish anything closer than 30 miles to anyone I give a shit about. Got it.

What does the MOAB do that the British 'Grand Slam' bomb, designed by Barnes Wallis, didn't do in WW2? The objective of the Grand Slam was to cause a localised earthquake and destroy any buildings from underneath. it just seems to be an incredibly expensive way to do the same job.