Applicable requirements (Exclusions)

I'm working in a telecommunications tower manufacturing company. We outsource design and development of self-supporting towers. The designer gives us the drawings and the calculation memories for structure loading, and then we manufacture (we don't approve drawings since we don't have the required competence). Two questions: 1) What kind of controls can we have for this external provider (some kind of license for structural design would be enough)? 2) How can design validation be demonstrated since they only deliver documents?

 

The control for the supplier can be based on the results of the validation performed against their design. A third party can be engaged to perform strength of the structure testing.