[ RadSafe ] A simple, down to earth beta dose rate question

[Olsson Mattias :MSO]

Dear all,

I got a question that is a bit outside of my field since I'm not as much of an RP person as many others here (rather a radiochemist). The question was which type of beta source is most suitable to calibrate a Smart Ion beta dose rate meter. The alternatives are Sr-90/Y-90, Kr-85 and Pm-147. I realize that the nuclides vary in beta Emax more or less from high to low in the order written (500 keV+2.3 MeV; 700 keV; 200 keV).

The instrument will be used in an environment with mostly Co-60 but also some Co-58 and Ni-63 as beta contributors. Most of the beta radiation will then be about Emax 300 keV from Co-60, but Co-58 will contribute with some 1,3 MeV and Ni-63 with some 70 keV.

I would guess myself that Sr/Y would be the most appropriate to make sure that the dose rate response is not underestimated. I have no feeling of how much of a difference it would make, though. Any advice?

All the best,
Mattias Olsson, Sweden