[MW:13610] Applicability of Impact testing for Non pressure parts welded on non pressure parts (inside the vessel)

Dear Expert,   Kindly advise on following;   Suppose I have a vessel with MDMT minus 48deg C, we have support plate (SP1) (inside the vessel) welded with vessels, on which I am going to weld another support plate (Sp2),   My question is whether this (SP1 & SP2) required to have impact tested to minus 46deg C or only SP1?   Similarly would saddle supports of this vessel require matl with impact testing.   Thank you in advance..   Ali Mhaskar UAE