For what it’s worth the nuclear power plant I worked at ran mostly on LabView. We compiled the code on PCs onto dedicated LabView boxes. No Fortran was ever used.
I say that as someone who has worked in nuclear safeguards.
In essence, that means the simplest approach is to use dedicated and or standardized systems (i.e.: in measurement/accounting) wherever possible then there's little or no argument when the inspectorate arrives. (From my comment you'll know my background.)
Jesus wept!
-Signed, a physicist with 20 years LabView and Fortran experience.