Re: background vs man-made emmissions - fallout

[GlennACarlson@aol.com]

_From http://www.city.hiroshima.jp/C/City/ABombDamage/07.html

"7.2 Residual Radiation 

High levels of residual radiation were present on the ground for a certain 
period of
time starting one minute after the explosion.  Residual radiation came in the 
form of
induced radioactivity produced secondarily as a result of the nuclear 
reaction of
neutrons when initial radiation collided with the soil and building 
materials, and it
also came from nuclear fission products and unfissioned uranium scattered by 
the
bomb. 

It is quite likely that anyone entering the area within 1 km of the 
hypocenter within
100 hours after the explosion to search for people or help with relief 
efforts was
affected by radiation coming from the soil and other such places due to 
induced 
radioactivity. In addition, soot and dust saturated with induced radiation 
from nuclear fission products and unfissioned uranium scattered at the time 
of the bombing were carried high into the atmosphere and later fell to the 
ground as radioactive fallout, giving rise to further possibilities for 
contamination. 

7.3 Black Rain

As the downtown area erupted in huge fires after the explosion, intense 
firestorms
and whirlwinds developed. After 20-30 minutes, black rain began to fall in a 
wide area
stretching from downtown to the northwest.

Large amounts of fallout, referred to as "Ashes of Death" were contained in 
the rain
in the form of radioactive soot and dust and caused contamination even in 
areas
remote from the hypocenter.

According to a study after the bombing, heavy rain fell in a 19km x 11 km 
area and
light rain fell in a 29km x 15km area, but there have been testimonies that 
black rain
fell in places outside these areas as well."

Glenn A. Carlson, P.E.
glennacarlson@aol.com

> Subj:  RE: background vs man-made emmissions - fallout
>  Date:    4/30/2000 7:18:00 AM Central Daylight Time  
>  >  
>  > Regarding your comment, what about exposure from fallout?
>  > 
>  > Glenn A. Carlson, P.E.
>  > glennacarlson@aol.com
>  > ************************************************************************
>  > 
>  Reply :  as far as I know, there wasn't any, since in both cases it was a
>  high-altitude explosion. This was confirmed by radiation surveyors on the
>  ground there soon after the explosions.
>  
>  Jaro
>  frantaj@aecl.ca
>  *************************************
>  
************************************************************************
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