What You Need to Know
Since 2008, the testing and certification of rockfall catchment fences has been carried out under a European-wide harmonized guideline published by the European Organisation for Technical Approvals entitled
Structure
The primary aspects of ETAG 27 deal with test setup and methodology, certification requirements, and compulsory documentation. Some highlights are:
Certification Process
Testing for systems according to ETAG 27 guidelines is carried out at facilities in Erzberg, Austria by an independent approval body. The body is responsible for the initial type-testing and inspection of the factory and production control. They are also responsible for the on-going supervision and assessment of production control and the issuance of the certificate of conformity.

References
EOTA (2008) ETAG 27: Guideline for European Technical Approval of Falling Rock Kits. 2008. Brussels, Belgium.