[ RadSafe ] Radon Daughters on People [was "Salsman warning"]

Brennan, Mike (DOH) Mike.Brennan at DOH.WA.GOV
Mon Apr 12 12:07:04 CDT 2010

Hi, Rick.

Here is a somewhat more fleshed out account:

>From the article:

Meanwhile, the Watras house was found to have 4,400 picocuries of radon
per liter (pCi/L) of air in the cellar, 3,200 pCi/L in the living room,
and about 1,800 pCi/L in each bedroom. (To put these numbers into
context, having 4 picocuries of radon per liter of your indoor air is
roughly equivalent to receiving 200 chest x-rays per year.) 

I have never heard that anyone in the Watras family has developed lung
cancer, and I am fairly sure that the word would have been spread.
Still, I doubt even people who dismiss radon programs as useless would
feel comfortable with 1,800 pCi/l in their bedroom.

As for detecting radon daughters on clothing, it depends on the
concentration, type of clothes, and instrument.  The situation I have
heard of it happening most often was "back in the day" at Hanford.
Polyester apparently develops a nice static charge, which attracts the
charged radon daughters floating in the air.  As I understand it, it was
a source of great humor for somebody being frisked out of a rad area
would have pants taken because of "possible contamination".  If, after a
couple of hours sealed in a plastic bag the levels dropped considerably,
they would get their clothes back, but their work wardrobe would have
been shifted to the denim end of the scale.  

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Hansen,
Sent: Monday, April 12, 2010 9:27 AM
To: radsafe at health.phys.iit.edu
Subject: [ RadSafe ] Radon Daughters on People [was "Salsman warning"]


The incident you mention of the nuclear power plant worker coming to
work contaminated with radon daughter products is briefly described on
the Pennsylvania Department of Environmental Protection web site:

The Saga of the Bureau of Radiation Protection
...Another seminal event for the Bureau occurred on December 19, 1984.
Notification was received from the chief raddie at Limerick that a
worker was coming to work contaminated. The contamination was detected
by a portal monitor. The contamination was natural. The utility had the
worker's home checked, and found extremely high concentrations of radon
there. The Limerick chief raddie reasoned correctly that the problem was
not a utility problem, but rather a state problem. The radon story began
with that phone call.
In the early months of the radon project, attention was confined to the
Boyertown area. A field office was established in Gilbertsville. By the
end of 1985, the project included the entire Reading Prong and adjacent
areas. By late 1986, the program began to go statewide.

I have a question for radsafe:

What are some methods to use in the field to determine if low levels of
radiation detected on a person or clothing is due to radon daughters
rather than radioactive contamination from other sources?

Two situations come to mind. First, during a law enforcement
investigation of possible illegal use of radioactive material, the
persons involved (including the officers) may be checked for radioactive
contamination using handheld survey meters. 
A second situation would be emergency response personnel checking fellow
responders and members of the public for contamination at the scene of a
potential incident involving radioactive material.

Depending on the organization, the personnel may have access to survey
meters with GM pancake detector probes and NaI gamma detector probes
(such as 1-in. diameter by 1-inch long NaI detectors). Hand-held
NaI-based radionuclide identification instruments (or RIIDs) may be
available. Some organizations also have alpha-beta scintillator
contamination probes, but most probably will not. 

Examples of this type of situation include training exercises where
radiation levels exceeded twice background levels on some of the Tyvek
suits worn by responders (especially during winter with low humidity).
Another possible example is workers initially thought to be contaminated
from a leaking sealed radioactive source because radiation (actually
from radon daughters) was detected coming from workers' hands, clothes,
and chairs.

Rick Hansen
Senior Scientist
Counter Terrorism Operations Support Program
National Security Technologies, LLC, for the U.S. Dept of Energy
hansenrg at nv.doe.gov

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