One can unfortunately find certificates o the Internet which give the appearance that all studs are CE certified.
At present there is no general CE marking of welding elements in accordance with DIN EN ISO 13918,except for the case that the Center of Competence in Civil Engineering (Deutsches Institut für Bautechnik, DIBt) has certified a construction product (e.g., consisting of studs with base material - concrete anchor on a plate)!
The CE marking of construction products (DIN EN 1090 Execution of steel structures and aluminium structures) implies that the conformity verification procedure defined for a given construction product regarding conformity with the technical specification on which the CE marking is based was successfully passed and that the construction product is created in such a way that the structure can fulfil the essential requirements given proper planning and execution.
Thus, a construction product produced in accordance with this harmonised standard requires confirmation of its conformity with this standard.
A CE marking for welding elements as construction products cannot occur until a harmonised standard exists; the current standard for welding elements, DIN EN ISO 13918, has no corresponding Annex ZA, however, and is therefore not harmonised.
As a result, studs designed according to DIN EN ISO 13918 may not be brought to market with a CE marking. As verification for compliance of the geometric, mechanical and chemical properties with the requirements of the standard, the studs are to be delivered with inspection certificate 3.1 acc. to DIN EN 10204:2005-01.
In the event of damage, an incorrect CE marking of construction products can have legal consequences.
Statement DIBt (Deutsches Institut für Bautechnik) dated 12 August 2013 (German).
Downloadlink: DVS-Verband/German Welding Society