[ RadSafe ] The use of K-40

[Olsson Mattias :MSO]

There was some talk about potassium on the list recently and I know that K-40 is sometimes used to verify the stability of on-line gamma monitors for for example stack emissions from power plants. It is usually argued that it gives a single, nice peak at such an energy (1,46 MeV) that it is not disturbed by background; neither does it cause much background since the source can be kept very small. (This concerns a shielded detector, of course.)

I don't feel any need to question the past experiences of this nuclide as a verification sample but what I do wonder is:

1) How is K-40 manufactured (if it is...). Separation from K-39? Sounds expensive.
2) If K-40 is manufactured as a reasonably enriched product, who sells it?
3) Is this sort of use of K-40 a common practice?

Have a good day, folks!

-- 
PhD Mattias Olsson, FTKS
Forsmarks Kraftgrupp AB
SE-742 03 Östhammar
Sweden

t. +46(0)173-81952
m. +46(0)705-801952
e. mso at forsmark.vattenfall.se