soft core fault tolerant

Hi everybody, I've a question...

is there a certification or something that decides if a soft core is fault tolerant or not?

and another question...I've seen that LEON3-FT is radiation tolerant only implementd on RTAX Actel FPGA. Is it right?

Excuse me but I'm confusing about it becuase somebody speaks about LEON3-FT (fault tolerant) for space application where is better to say radiation toleran...mny doubts!!!!!

And, the last question...is there somebody that knows another soft core "radiation tolerant" (for space application)?

Many thanks in advance!!!!

Marco