Class B Fleet Base
The gargantuan organisation that is the United Stars Navy has everything tightly regulated. Everything is quantified, codified and spelled out in so called NAV REGS.
A Class B Fleet Base is the second largest Standard Fleet Base Class means that there is a prepared NAV REG covering everything from construction, to operation and staffing requirements.
A Class B Base must be big enough to service and house the entire crews of an entire Battle Group (hence the B) and be able to service and repair any ship class in the fleet it is supposed to support. The purpose of a Fleet base is to provide supplies, logistics to that fleet. Have staff and offices for Personnel , Administration etc. Medical facilities big enough to service wounded and sick. Provide housing and recreation to Service families including schools, shopping facilities and similar services. It must provide enough landing space to accommodate all ships of that battle group if necessary. In addition to all that a Class B Fleet Base must provide security, intelligence and support for the region it is placed. Further requirements are Laboratories, Holding facilities, Military Police etc.
Since a standard Union Battle Group consists of: five Arsenal ships, five carriers five Dreadnoughts, 20 Ultra Battle Ships , 100 Battle ships, 200 Super cruisers, 200 Space Cruisers, 80 Heavy Frigates, 120 Frigates, 200 Destroyers, 2 Hospital Ships, 200 Fleet Tenders, 1 Mobile Dockyard, 2 Fleet Repair ships, 25 Marine troop ships, 1 Wurgus Solar Enticer Ship,25 Marine troop ships and over 200 other support craft, a Class B Base is usually located on a planet, moon or large asteroid. Personnel and Support Personnel can easily reach 1-2 Million individuals.
Other Classes are : Fleet Base F (Full Fleet) Fleet Base M (Multi) Fleet Base O (Outpost)