Today I've been trying to find a suitable outdoor enclosure for the GM Tube,pcb and UKHASnet node bits...
I think i've figured out that most of the radiation emitted from a piece of Uranium glazed pottery (off ebay!) is beta particles...
Beta absorbers seem to be a lot of plastics, ABS boxes absorb a lot, ceramic tiles absorb most, if not all of the particles.
The clear plastic from 50pk of writable cd's absorbs a little but not too bad.
Next test is to try some fiberglass....