The amount of viable released spores is strongly inhibited by solar radiation. The spore load is also reduced by precipitation and by germination .
Survival factor of released spores : set SFRS(t)=(1-(Qo(t)-270)/540)/1,5 - inhibition by radiation
SFRS will be negative when Q0 (solar radiation) is > 810 w/sqm. This means that VRS will be negative, which in turn makes RISK negative. We change the setting of Result objects so that all negative RISK values are converted to 0.0.
