Red Sector - Command and Control
Gold Sector- Security Facilities
Blue Sector- Medical, Science and Diplomatic Facilities
Green Sector- Military Facilities
Brown Sector- Civilian Areas
Grey Sector- Engineering Facilities
This is for security reasons. Every Visitor and occupant is given a level of access. Civilians only have access to Brown and Blue Levels, Visiting Diplomats have access to Brown, Blue and Red levels. Starfleet Personnel have access to all levels except Grey, Command, Engineering, Security and selected Medical and Science Personnel have access to all levels including Grey.
Grey is restricted in this way because it is the location of the Fusion Reactors, which , if tampered with, could destroy the station.
