@Terry
>dirty bomb
The only "dirty" "attack" russians have been subject to has been their moronic attack on Chernobyl, where they ended up digging into radioactive soil.
@Hoss @Terry
Hard to say for sure. To some degree every country is aware of what kind of radioactive material everyone else has at their disposal, what kind of concentrations their bombs should have, what byproducts they'd produce etc. But if we're talking about a dirty bomb, I imagine you could easily mask it by just throwing in random stuff in there to throw off readings.