Personnel may be hurled against objects or thrown to the ground. At sea, the shock wave produced by an underwater burst, can produce various secondary injuries. Primary burns are a direct result of the thermal radiation from the bomb. Secondary burns are the result of fires caused by the explosion. Flash burns are likely to occur on a large scale as a result of an air or surface burst of a nuclear weapon.
Thermal radiation travels in straight lines, so it burns primarily on the side facing the explosion.
Under hazy atmospheric conditions a large proportion of the thermal radiation may be scattered, resulting in burns received from all directions. Depending on the size of the weapon, second-degree burns may be received at distances of 25 miles or more. The intense flash of light that accompanies a nuclear blast may produce flash blindness at a range of several miles. Flash blindness is normally of a temporary nature, though, as the eye can recover in about 15 minutes in the daytime and 45 minutes at night. A greater danger lies in receiving permanent damage to the eyes caused by burns from thermal radiation, which may occur 40 miles or more from the nuclear weapon.