Brett We have the same equipment ( Alpha Ionograph) we use 1.5ug/cm2 as our pass / fail criteria based on Def Stan 00-10. This is 9.7 ug/in2 regards Chris Evans MBD UK _____ _|___|_ [(*) (*)] ¬¬¬/|\¬¬¬¬¬¬¬¬/|\¬¬¬