It will depend upon what the Contract Documents specify for the governing code and what your specific responsibilities are in the inspections.
If they are built with Alum for the supports and the ramp as well as the railing then more than likely D1.2 will apply. If you are doing the Special Inspections then you may also have to work with IBC: 2012 and even a bit of AISC as to the frequency of inspections as IBC pretty well defers to AISC Chapter N for 'Before', 'During', and 'After' Welding inspections.
He Is In Control, Have a Great Day, Brent