In Belgium, there is a commission for the arbiters, see in the committees page.
There are 5 categories of arbiter : C, B, A, FIDE and International.
For being arbiter C, you must follow curses of cultural federation (FEFB, VSF or SvDB). There are conditions for be upgraded B and then A.
To be authorised to referee a fide-approved tournament, you must be arbiter C, B or A and have a FIDE licence.
For being FIDE & international arbiter, you must follow FIDE training curses.
You can find here the list of the arbiters in Belgium.
Here is the Fide’s manual of arbiter : english, dutch, french, german