Table E.1 and E.2 in API 650 V13 define Fa and Fv factors as functions of site class A thru F. The values do not align with those in ASCE 7. Anyone knows why API doesn't use the same Fa and Fv as in ASCE 7?
ASCE 7 has updated those factors as they went along, and the API/AWWA factors haven't been updated- I think this is the issue, at least.
In ASCE 7-16, they had an addendum addressing the changed factors.