Hello Daon!
Hows the weather in Israel/
Have you tried contacting the Netherlands Institute of Welding (NIL) yet? http://www.nil.nl/index_e.htm is their website, and I believe in the Institute's information page, you'll find some e-mail adresses to inquire more about NEN 3650.
I'l give you some of the E-mail addresses listed that are relevant to your concern which could save you some time in your search, and I already joined their newsletter so I might give you more info soon, so here goes:
Bob Boesmans, Director, boesmans@nil.nl
Marcel van Teylingen, Certification, teylingen@nil.nl
Oki Dolfing, Training (Higher Ed.), dolfing@nil.nl
Gerda de Feiter, Vocational Training, Feiter@nil.nl
Riek Schoonenboom, Vocationla Training, schoonenboom@nil.nl
Henk Hendriks, Training, hendriks@nil.nl
Wim Pors, Information Development, pors@nil.nl
Henk Bodt, Information Transfer, bodt@nil.nl
Hope this helps!!! Good Luck and I'll post more when I recieve more info!
Respectfully,
SSBN727 Run Silent... Run Deep!!!