Conventional Warfare: Ballistic, Blast, and Burn Injuries [pdf]

> Personnel oriented end - on to the blast wave (that is, lying down with either their head or feet pointed toward the blast) offer little resistance to the dynamic pressure component of the wave, and the incident shock (or side-on pressure) constitutes their air blast dose (Figure 7-8). The end - on orientation also gives the best protection against being displaced by the blast wind.

For persons side-onto the approachingblast wave, the dynamic pressure and incident pressure are additive (Figure 7-9). In the region of short - duration blast waves (a positive phase of 3 msec or less), there is a twofold difference in magnitude between the curves for the end-on and side -on orientations.

Individuals positioned against a large reflecting surface and normal to the incident shock would have the peak reflected pressure as their effective blast dose (Figure 7-10).

For example, the threshold (that is, the lowest overpressure at which trivial lesions are first detected) for lung injury is about 12psi for blast waves of greater than 20-30 msec duration; scattered pleural petechiae are the threshold injury. Subjects end-on to the blast would require an incident shock of 12 psi static pressure to cause this lesion. If the subjects are oriented side-on,an incident shock of 10 psi (with an associated dynamic pressure of 2psi) would cause equal damage. If the subject is against a reflector, an incident shock of just over 5 psi (reflecting to 12 psi) would cause the same injury. Although all three examples have different incident blast waves, the biologically effective blast loading is the same.

Page 256 (241 in the page print) for "The Physics and Mechanisms of Primary Blast Injury"; I was trying to find information about the effect of lying flat on the ground for surviving a blast, there's some graphs on page 269.

Here is that chapter as a standalone PDF - https://ckapfwstor001.blob.core.usgovcloudapi.net/pfw-images...

This would be relevant information to those living in Ukraine right now.