ASD-STAN prEN 9253 (01/11/2018)

This standard defines a risk-performance based methodology for the surveillance of Design Suppliers compliant with EASA Part 21.A.239 (a) (3) and 21.A.239(c), and equivalent military DOA requirements (EMAR 21). That methodology is applicable to any level of Design Supplier’s (Sub Tier n) position in the supply chain of a DOA Holder.
NOTE: For convenience in this document the Tier n (who can be DOA holder itself or one of the Tier n below) is called ‘purchaser’ when monitoring the subsequent design supplier (sub Tier n+1).
It is assumed in this standard that the purchaser since DOA holder has already an Independent System Monitoring in place and effective