Table A-1. Comparison of Weapons Effects (Radii of Effects in Kilometers—Airburst)
| 1 KT | 20 KT | 100 KT | 1 MT | 10 MT | |
|---|---|---|---|---|---|
| NUCLEAR RADIATION (1,000 cGy) |
| ||||
| BLAST (50% INCIDENCE OF TRANSLATION WITH SUBSEQUENT IMPACT WITH A NON-YIELDING SURFACE) |
| ||||
| THERMAL (50% INCIDENCE OF 2ND-DEGREE BURNS TO BARE SKIN, 10 KM VISIBILITY) |
| ||||
A-3. Physiological Effects of Nuclear Weapons
The physiological effects of nuclear weapons are the result of exposure to the blast; thermal radiation; ionizing radiation (initial or residual) effects; or a combination of these. For smaller weapons (less than 10 KT), ionizing radiation is the primary creator of casualties requiring medical care, while for larger weapons (greater than 10 KT), thermal radiation is the primary creator of casualties.
a. The rapid compression and decompression of blast waves on the human body results in transmission of pressure waves through the tissues. Resulting damage is primarily at junctions between tissues of different densities (bone and muscle), or at the interface between tissue and airspace. Lung tissue and the gastrointestinal system (both contain air) are particularly susceptible to injury. The tissue disruptions can lead to severe hemorrhage or to an air embolism; either can be rapidly fatal. Direct overpressure effects do not extend out as far from the point of detonation as the drag force and are often masked by the drag force effects. A typical range of probability of lethality, with variations in overpressure for a 1 KT weapon, is shown in [Table A-2].
Table A-2. Range of Lethality of Peak Overpressure
| LETHALITY (APPROXIMATE %) | PEAK OVERPRESSURE (ATMOSPHERES) | DISTANCE FROM GROUND ZERO; METERS |
|---|---|---|
| 1 | 2.3-2.9 | 150 |
| 50 | 2.9-4.1 | 123 |
| 100 | 4.1+ | 110 |
(1) The significance of the data is that the human body is relatively resistant to static overpressure compared to rigid structures such as buildings. For example, an unreinforced cinder block panel will shatter at 0.1 to 0.2 atmospheres.
(2) Overpressure lower than those in [Table A-2] can cause nonlethal injuries such as lung damage and eardrum rupture. Lung damage is a relatively serious injury, usually requiring hospitalization, even if not fatal; whereas eardrum rupture is a minor injury, often requiring no treatment at all.