Worker registered in the merchant navy pool
If the non-European worker is registered as a seaman in the Belgian merchant navy pool, the type of authorisation depends on the duration of the employment in Belgium.
(art. 2.8 royal decree 09/06/1999)
The seaman will be working in Belgium for more than 90 days.Apply for a single permit "in the frame of an exemption"
The seaman will be working in Belgium for maximum 90 days.
You do not need to ask Brussels Economy and Employment for employment authorisation in order to work in Belgium. (automatic exemption by virtue of article 2.8 of the royal decree dated 9 June 1999)