The engine room is mostly circular with one inaccessible door, forcing the player to explore the area in a clockwise fashion. The area inaccessible via the main room is linear, with straight hallways and corridors. Scattered throughout are aliens, support drones, and guardian drones. There are also a few opportunities for the player to sabotage turrets.
If you take Somah into the engine room she will make comments about smelling flammable gas, and wonder aloud 'what a well placed grenade would do to that thing.' There are several places where the flammable gas can be ignited.
pc If exploring the area with the console command tcl, you can find a switch under the ground of the northwest room labeled "Release Control." In the GECK it's labeled DLC05ERoomGasTrapControl, and in the console it's labeled xx007a53. [verified]