Alpha Labs - Sector 1: Union Aerospace Science Division

Alpha Labs - Sector 1: Union Aerospace Science Division is the fifth level of Doom 3. Built in 2095 and located on Site 2, Alpha is the UAC's center research lab. Sector 1 houses the EPD (Elemental Phase Deconstructor) and the Hydrocon. Maggots are introduced midway through the level in a cutscene.

Summary
Sergeant Kelly radios in again, urging the Player to meet up with Bravo Team as soon as possible. The Player enters Alpha Labs's Reception area and clears out the zombies inside. He then uses a security terminal to open a locked door and proceeds deeper into the facility. He fights his way to the EPD Lab, where he finds that the only way to go further is through the EPD collection chamber. After clearing out the demons and zombies in the EPD control room, he opens a repair gate, giving him access to the collection chamber. The Player crawls into the collection chamber (being sure to avoid the instantly fatal EPD beam) and exits through a maintenance conduit.

The Player heads further through Alpha Labs, until he runs into a fire blocking the way. He finds a monitoring station at the EPD Particle Emulsifier and uses it to extinguish the fire. Upon reaching the EPD Contaminant Purge room, he encounters a new enemy - Maggots. After defeating the Maggots, the Player crawls through a crawl way underneath the floor and arrives near the section responsible for maintaining the Hydrocon. Eventually, he encounters a survivor - George Krietman - who warns him not to shoot the Hydrocon tanks inside the lab. The Player proceeds further into the base, where he uses the PDA of the deceased Bernie Lipsitz to gain access to the Hydrocon itself. Here, he catches a glimpse of Counselor Swann and Jack Campbell heading through Hydrocon Observations. The Player finally reaches the exit elevator, where he defeats another ambush by Maggots, before taking the elevator to the next level.

Walkthrough
After transfer, enter the reception ahead, and head directly to the terminal on the right behind the desk. Activating it will light up the area, making it easier to engage the zombies.

The Blue 16 door leads to the Atomic Stabilization Hub. One shotgun Z-Sec should be near the door and you may be able to attack before he reacts. Two other Z-Secs are to the right, taking cover. Proceed left. Opening the Blue 17 door has a crouching imp ready to attack, and released another zombie from the main room. Two more Z-Secs approach from the Blue 18 door on the opposite side of the EPD Observation Platform.

Enter the EPD Lab. You will be attacked by Imps. Head to the control room, where the screen turns red, after which three imps will attack. Head to the console that allows opening the repair gate. There will be plenty of attackers soon after the screen turns red, especially from dark corners. If you get injured, there's a health station with 73 units. With the repair gate open, you can advance, but be sure to duck under the beam to avoid damage. The chamber has a conduit that can be opened to exit, although there is a Z-Sec waiting outside.

In EPD Junction 2, the way forward is blocked by two flame jets. Head down the corridor opposite these jets to the EPD Particle Emulsifier. A few enemies later, you should reach a console to seal the leak, and head to the EPD Particle Scrubber.

The EPD Particle Scrubber will have one Z-Sec running from the door ahead. Approaching the door opens a storage closet behind with one Imp and one Z-Sec. The platform below has armor, with an imp released from infront of the armor.

Going through the door to the EPD Contaminant Purge will start the cutscene introducing Maggots. They are easily defeated with several bullets. When they're finished, you can go through the floor and into the crawlway. The first exit allows you to proceed, while the second only contains a medikit and a few clips.

Alpha Labs Junction 3 has a few enemies, simply head to the Hydrocon Condenser. In this room, the floor sometimes gives way, only serving as flavor rather than being a threat. In the Oxygenator, watch for two barrels being thrown, and two enemies on the upper floor. Back in the condenser, the stairs will give away - if they do but you're on the wrong side, you can jump and climb its railing.

In Hydrocon Junction 1, you're attacked by two imps, one in front and one from behind. Head to Hydrocon Siphon, and climb the ladder. You will reach G. Kreitman, he tells you not to shoot the glass, but you can continue and collect Bernie's PDA to open the Hydrocon Control door. A few enemies are past the door, with imps in the hydrocon lab. A health station with 44 units is just before the Alpha Labs Main Junction.

Door Blue 19 leads to a dead end, turn right to doors Blue 20 and 21. One maggot appears. Blue 22 is the final door, with several maggots attacking at once, and the elevator being just ahead.

PDAs

 * Kyle Berger: At EPD Lab.
 * Jack Smith: At EPD Particle Emulsifier.
 * Bernie Lipsitz: At Hydrocon Stabiliazation
 * George Krietman

Video disks

 * Elemental phase deconstructor: In EPD Lab, in the control room.
 * Hydrocon: In Hydrocon Control.

Characters

 * Sergeant Kelly
 * UAC announcer
 * George Krietman
 * Elliot Swann
 * Jack Campbell

Enemies
Total enemy count for the Veteran difficulty:

Weapons/Items
There are also 3 health station on the level: one with 100 health in reserve, one with 73 health, and another one with 44 health.

Cabinets

 * Storage Cabinet #009: 752. Found in EPD Lab, code learned from Kyle Berger's audio log.

Trivia

 * In Hydrocon Junction 1 where the player is attacked by two imps, there's a small semi-hidden control panel on the side of one of the columns which can be used to open the armory in that room.
 * The door from EPD Particle Scrubber to EPD Contaminant Purge can be jammed open if a Z-Sec is killed and drops the machinegun in the doorway. After the Maggot introduction cutscene, retreat is still possible through the open door. If the player collects the dropped weapons (by firing a machinegun and reloading) that jammed the door open, the door will close and lock until the necessary maggots are killed.  If they're on the other side of the door, game progress is deadlocked without the use of cheats or reloading a prior save.