This area is mentioned in Black Mesa Announcement System announcements in Sector C and D.

2.2.1 Hazardous Materials Handling Bays.

1 Central Command and Communication Center.

One vent found near the tracks directly links to Level A of Sector F, where Shephard witnesses Freeman's departure to Xen. There Adrian Shephard confronts the Black Ops that have taken hold of the area. Another side is accessed via a Secured Access of the Lambda Sector Transport, located on level B of the Sector E Materials Transport. One side of Sector F is linked to the rest of the facility through the Central Command and Communication Center, accessed through Waste Processing Area 3, and where Gordon Freeman accesses the facility.

The core of the reactor facility consist of four levels (A, B, C, and D) that fuel an extremely powerful interdimensional Portal located on Level A, where Survey Teams are equipped, and sent over to Xen. There can be found the heavily fortified Lambda Reactor Complex, the site of Black Mesa's top secret teleportation labs, mostly made of a huge reactor consisting of the Lambda Reactor Coolant System, and the cylindrical Lambda Reactor Core. It is connected to the Yellow Line of the Black Mesa Transit System. Sector F Lambda Complex is one of the seven main sectors of the Black Mesa Research Facility.

Half life lambda core