49 CFR 173.403 states: "Specific activity of a radionuclide means the activity of the radionuclide per unit mass of that nuclide. The specific activity of a material in which the radionuclide is essentially uniformly distributed is the activity per unit mass of the material." There is some judgment regarding "essentially uniformly distributed". Some examples I would use are: solution of radioactive material in a drum: I would calculate the specific activity as the activity per mass of solution, not counting the mass of the drum radwaste encapsulated in concrete: I would calculate the specific activity as the activity per unit mass of the waste material, not counting the mass of the encapsulating material The opinions expressed are strictly mine. Here's to a risk free world, and other fantasies. Bill Lipton liptonw@detroitedison.com
- To: Multiple,recipients,of,list,radsafe@romulus.ehs.uiuc.edu
- Subject: Question on Specific Activity
- From: "radsafe@romulus.ehs.uiuc.edu" <radsafe@romulus.ehs.uiuc.edu>
- Date: 17 Sep 97 14:30:53
- Reply-to: radsafe@romulus.ehs.uiuc.edu
Hello, I have a question regarding the definition of Radioacive material in 49 CFR Part 173.403. If the specific activity is greater than 2 nCi/g, then it is radioactive. When determining specific activity, what can you average this over? Is it just the source/sources inside or the entire contents and container? Sincerely, Tim Paul, MS, CHP UCLA Radiation Safety Lab A6-060 C CHS Box 957061 Los Angeles, CA 90095-7061 -------------------------------------- e-mail: tjpaul@ucla.edu Tel No.: (310) 794-7365 Fax No.: (310) 206-9051 http://www.facnet.ucla.edu/radsafety/ --------------------------------------