Port Security Act supervisors patrol the port area in Vlissingen and Terneuzen. They also conduct audits and physical checks of ISPS facilities, with a minimum of one visit per year to each port facility. On these audits, a questionnaire is filled in during an interview with the PFSO and/or their deputy. The supervisors have been appointed for these tasks by a decision of the Mayor and alderman (municipal executive) and the the provisions of the General Administration Act apply.
Within the port area in Ghent, the security plans are overseen by the National Authority for Maritime Security (NAMB) as well as the Local Committee for Maritime Security in Ghent (LCMBG). Both agencies may visit the ISPS facility for the purpose of conducting inspections, either announced or unannounced.