Re: Re[2]: mantle

[Charles Willis <caw@nrc.gov>]

Jim,

I suppose we are free to have our words mean whatever we want but for convenience in communication, there is something to be said for using  words to mean what other people think they mean.  Generally, radioactive materials are deemed to be those materials that spontaneously emit ionizing radiation.  With this definition, and other conventional use of the words, there is no question but that essentially all real materials are radioactive.  Lantern mantles tend to contain carbon which includes carbon 14 along with hydrogen containing tritium.  Furthermore, mantles tend to be "contaminated" with radon and radon daughters as well as fallout from the weapons tests, and other things.  (Mantels are commonly made of wood or ceramic materials so they also are radioactive.)  Of course, some things are more radioactive than others.  I too select thoriated lantern mantles for radiation demonstrations.

I do not like to nit-pick, but it is important in the public relations arena to establish that , in dealing with radioactive materials and radiation exposure, the question can never be yes or no but must be about how much is permissible or acceptable.

Charlie Willis
caw@nrc.gov
                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
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