[ RadSafe ] Fwd: Rn-222 from Depleted Uranium
achris1999 at gmail.com
Tue Aug 20 14:25:40 CDT 2013
There is no radon, because there is no radium. If you take a look at
the half-lives of the daughters (sorry, *progeny*) intermediate
between U-238 and Ra-226, you will see that it takes near-geological
time to reach even 50% secular equilibrium, never mind >99%.
---------- Forwarded message ----------
From: Andrew McGechaen <A.McGechaen at buffaloinspection.com>
Date: Tue, Aug 20, 2013 at 2:18 PM
Subject: [ RadSafe ] Rn-222 from Depleted Uranium
To: "radsafe at health.phys.iit.edu" <radsafe at health.phys.iit.edu>
My building stores about 300kg of depleted uranium. I have read that
the indoor radon hazard in buildings originates from decay products of
uranium in soil. Checking the Radium Series, I noted U-234 (245500a)
-> Th-230 (75380a) -> Ra-226 (1602a) -> Rn-222 (3.8235d), with the
attached half-lives. Fetter and von Hippel (1997) give U-234 at a
concentration of 7 ppm in DU.
Is it safe to ignore the decay chain of U-238 to U-234, and consider
only the initial concentration of U-234 ?
Is it realistic to assume that the residue of Ra-226 in the DU would
be zero after chemical refinement?
I assume the U was depleted and chemically refined years or decades
ago. What activity of Rn-222 would exist now?
Might radon escape through cracks or communicating voids in the
Might any appreciable quantity of radon escape from the uranium metal
by Fickian diffusion?
You are currently subscribed to the RadSafe mailing list
Before posting a message to RadSafe be sure to have read and
understood the RadSafe rules. These can be found at:
For information on how to subscribe or unsubscribe and other settings
More information about the RadSafe