[ RadSafe ] Re Question about Radon

Leo M. Lowe - SENES Consultants Limited llowe at senes.ca
Thu Apr 23 14:00:36 CDT 2009


Continuous indoor exposure (8760 h/y) to 4 pCi/L (148 Bq/m3) of radon 
would result in an approximate effective dose of about 4 mSv/y (0.4 
rem/y).  The dose equivalent to the lungs only would be higher, but 
the cite you give below (scroll down to "at what level is Radon 
dangerous?") compares the dose to an occupational exposure limit of 5 
rem/y (50 mSv/y), which is basically effective dose.  It appears that 
the quote below about the dose being 4 to 14 rem per year is high by 
a factor of 10 or more.

This calculation assumes a typical radon decay product equilibrium 
factor of 0.4 and the ICRP effective dose factor of 4 mSv (400 mrem) 
per WLM for members of the public.

Leo Lowe
Message: 10
Date: Wed, 22 Apr 2009 18:34:11 -0600
From: Steven Dapra <sjd at swcp.com>
Subject: [ RadSafe ] Questions about radon
To: radsafe at radlab.nl
Message-ID: < at mail.swcp.com>
Content-Type: text/plain; charset="us-ascii"; format=flowed

April 22

          Is anything true in this quote?

          "The "action level" recommended by the Environmental Protection
Agency for radon in the air is 4 picocuries/liter of air. It is difficult
to convert air concentrations to actual exposures in rems or sieverts, but
estimates are in the range of 4 to 14 rem per year at that concentration.
That makes it greater that all the other routine environmental exposures

          Okay, I know the first sentence is true.  Is it difficult to
convert air concentrations to exposure in rems?  Does 4 pC/l equal 4 to 14
rem per year?

          I got the quote from this website
<http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radon.html>.  Scroll
down to the "Radon compared to other radiation sources" sub-heading.  Any
comments on the rest of the site?

Steven Dapra

Leo M. Lowe, Ph.D., P.Phys.

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