High-Level Layout
Think of the airlock as three short zones in a straight line:
Inner Access Corridor – connects to the interior deck/habitat.
Lock Chamber – small sealed compartment with controls and gear.
Outer Access Point – opens to vacuum, a docking tube, or hostile atmosphere.
A typical footprint:
Inner Access: 5 ft deep, 10 ft wide
Lock Chamber: 10 ft deep, 10 ft wide
Outer Access: 5 ft deep, 10 ft wide
Total common size: 20 ft long x 10 ft wide (4 x 2 squares).
Functional Details by Zone
Inner Access Corridor
One heavy inner door (D) rated like a “starship interior” door; usually auto‑sliding but can be sealed and Forced Open at a high DC if power fails.
Interior control panel (C) to cycle the lock, override in emergencies, and show status (pressurization, outer door state, contamination warnings).
Often a small emergency locker (E) with basic med kit, tether line, and manual crank/ratchet for the inner door.
Lock Chamber
Two opposite doors (inner and outer) cannot normally open simultaneously; safety interlocks are software‑enforced unless tampered with.
Primary controls (C) on one wall: full cycle (equalize, open/close), manual repressurize/depressurize, emergency vent/abort, alarm.
Suit lockers (S) or racks for vac‑suits, helmets, mag‑boots, and tool belts along one side.
Emergency gear (E): fire suppressant, rad dosimeter, patch foam, spare filters.
Floor is usually grated for drainage/decontamination; ceiling has strip lights and cameras.
Outer Access Point
One or two outer doors (D): can be flush hatch, iris, or docking‑ring collar.
External control panel (C) on the interior side only, with a ruggedized exterior override at GM discretion (for rescue/sabotage scenes).
Narrow viewport or status strip (V) above the door showing exterior conditions (vacuum/atmosphere, pressure, temp, docking clamp status).
In poorer Outer Sphere or Frontier installs, downgrade inner walls from starship‑grade to patched steel/plastic and show missing suit lockers or improvised decon sprayers.
You can treat this as the “default small lock”; bulk cargo locks are just this pattern scaled up with two parallel chambers and wider doors.