Reply #29: effects of a 1 kiloton ground level detonation

[pokerfan]

Taken from the following site. They also have figures for 10kT and 100kT fission explosions. I included only the figures given for a 1kT device.

I don't know the population density of the area where it was detonated. Twenty miles north of Magic Mountain? I've been all over CA but not south of Monteray or north of Valencia/Santa Clarita. It looked like some kind of industrial park.

http://www.nti.org/e_research/cnwm/overview/technical3.asp

-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

The fireball from a 1-kiloton explosion at ground level would reach a radius of 150 meters. Everything within this radius would be completely destroyed.

A blast-wave overpressure of 5 pounds per square inch, which is associated with winds around 150 miles per hour, is enough to destroy wood-frame buildings and cause severe damage to brick apartment buildings; overpressure of this magnitude would be experienced at about 500 meters from a 1-kiloton surface explosion.

Prompt Ionizing Radiation: The distance from a 1-kiloton surface explosion at which a person in the open could receive a prompt dose of 500 rem from neutrons and gamma rays (the dose that will prove fatal within 30 days to about half the people receiving it) is around 1,100 meters.

A nuclear fireball radiates energy in infrared, visible, and ultraviolet wavelengths with enough intensity to burn exposed skin and char or ignite flammable materials at substantial distances. For a 1-kiloton surface explosion, the radiant intensities on a clear day are sufficient to cause second-degree burns on exposed skin at 600 meters.

Local fallout occurs when a nuclear weapon explodes close enough to the ground to vaporize and entrain in the fireball much larger amounts of solid material than that from which the weapon is made. When this vaporized material later cools and condenses into liquid and solid particles, many of these end up heavy enough to fall to the ground rather than remaining suspended in the atmosphere, and they carry with them a substantial fraction of the radioactive fission products and activation products produced in the explosion. The spatial pattern over which such fallout is deposited depends strongly on the wind patterns and atmospheric stability prevailing at the time. It is possible to make a rough estimate for the area over which a given dose from fallout will typically be equaled or exceeded, however. If the dose at the boundary of the area of interest is taken to be 500 rem within 48 hours to unprotected persons who do not leave the area, the answer comes out around 3 square kilometers per kiloton of fission energy release.