Path: utzoo!utgpu!watserv1!watmath!att!cbnews!military
From: oconnor@disney.crd.ge.com (Dennis O'Connor)
Newsgroups: sci.military
Subject: Re: Depleted Uranium Ammo
Message-ID: <15571@cbnews.ATT.COM>
Date: 14 Apr 90 04:10:58 GMT
Sender: military@cbnews.ATT.COM
Organization: GE Corporate R&D Center
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Approved: military@att.att.com



From: oconnor@disney.crd.ge.com (Dennis O'Connor)
drickter@BRL.MIL writes :
] ...  gamma radiation is considered the most harmful as it is able
] to penetrate the skin and would most likely affect internal organs after
] long term exposure. ...
] ( beta radiation is a non-penetrating radiation and therefore presents 
]   only minimal concern to those exposed.) 

This directly contradicts my own knowledge of radiation from
physics classes and from working as a technician on gamma-ray camera
image processors in nuclear medicine clinics in the NYC area :

Alpha particles are the least dangerous form of radiation. Composed
of two protons and two neutrons, an alpha "particle" is essentially
an energetic helium nucleus. Because of it mass and charge, it is
stopped quickly : a layer of clothing stops most alpha particles.

Gamma radiation is the next least dangerous radiation, for exactly
the opposite reason as alpha particles. Gamma rays are energetic
photons (i.e. "light") between X-rayas and cosmic rays in the spectrum.
Most gamma rays will go right thru a human being without interacting
with him or her : this is a vital principle to gamma-ray cameras.
Gamma ray cameras work like this : a gamma-ray emitting isotope
( usually technicium ) in a selected compund is injected into a patient.
The compound is selected based on what is to be imaged. Different
compounds bind to different parts of the body ( like blood or bone ).
Imaging the location of the gamma-emitter provides diagnostic info.

Beta radiation consists of energetic electrons. These can be quite dangerous
since depending on the energy level, they will penetrate anywhere from
a centimeter to several centimeters. By way of contrast : no shielding
or restriction on personel where needed when gamma-ray imaging was
done, but patients recieving beta radiation therapy where isolated
in a room by themselves. Beta radiation can be stopped by an inch
of wood or so, and does not travel very far in air.

Last, Neutrons are very dangerous. They have no charge but are
relatively massive. Plus they seem to have an affinity for
stopping in organic material. More on them I don't know.

Remember : the most common radiation-related injury is sunburn.
Hard-UV is pretty nasty stuff.
-- 
--
  Dennis O'Connor      OCONNORDM@CRD.GE.COM      UUNET!CRD.GE.COM!OCONNOR
  "Let's take a little off the top ... a bit off the sides ...
    trim the back a bit ... Surprise ! You've been bald-ed !"