Black Mesa Announcement System

The Black Mesa Announcement System is the public address system used throughout the Black Mesa Research Facility, relaying audible messages and announcements across the facility with a male voice. Additionally, a similar announcement system is mounted on trams to give general information about the facility and mention each stop, with a prerecorded female voice. Judging from its mechanical voice and fragmented, disjointed speech, it is probably a basic AI, similar to the Overwatch Voice.

List of announcements
Note that not all these announcements are heard in-game and sometimes only mentioned in the file "sentences.txt" located in each game's sound folder.

Half-Life

 * Hello. The Automatic Diagnostic and Announcement System welcomes you to the Black Mesa Research Facility. Remember: have a secure day! (from vox_login.wav, an unused sound file)

Hazard Course

 * Access denied
 * Access is forbidden
 * This door is locked
 * Will we do this all day?

Note: The above line indicates one of two things: Either this P.A. network is a sentient Artificially Intelligent computer or a scientist controls it from somewhere, either of whom are irritated by another scientist (in this case Gordon Freeman) attempting to open a locked door himself.

Sector C, before the incident

 * Agent Coomer, report to Topside Tactical Operations Center.
 * Inspection team to Radioactive Materials Handling Bay.
 * Agent 16, report to Administration Sub-Level 2.
 * Dr. Johnson, please call Observation Tank 1.
 * Dr. West, please report to Lambda Reactor Complex.
 * Dr. Cross, call 729 please.
 * Sergeant Bailey to Topside Checkpoint Bravo.
 * Cryogenic Safety Crew, report status at 1100 please.
 * Coded message for Captain Black, Command and Communication Center.
 * Sector C science personnel, report to Anomalous Materials test lab.
 * Dr. Freeman to Anomalous Materials test lab immediately.
 * Attention. Experimental Propulsion Lab test fire in 90 minutes.
 * Hydro Plant now operating at 60%.
 * Black Mesa topside temperature is 93 degrees.
 * Launch officer reports, alpha satellite deploy is nominal.
 * Dr. Birdwell reports superconducting interchange is activated.
 * Attention. Report any security violation to Administration Sub-Level 1.
 * Attention. Service personnel, please clear Helicopter Hangar 1.
 * Shield inspection: crew reports primary reactor nominal.
 * Transportation control reports, all systems on time.
 * Dr. Victor, report to Supercooled Laser Lab please.
 * Sergeant Guthrie, report to Topside Motorpool immediately.
 * Uranium shipment inspection team to Sector D.

Sectors C & B

 * Warning, high energy detonation detected in Materials Lab.
 * Attention, security personnel to Sector C immediately.
 * Warning, unauthorized biological forms detected in Sector C.
 * Warning, unauthorized biological forms detected in Coolant Maintenance Area.
 * Any damage control team to Sector C immediately.
 * Warning, Sector C elevator failure. Do not use.
 * Biohazard warning in Sector B and C.
 * Attention. Sector C science personnel, evacuate area immediately.
 * Warning, flooding detected on Sub-Level 3, Sector B.
 * Warning, anomalous energy field detected in Administration Center.
 * Attention. Any Sector C science personnel, please report status.
 * Attention. Sector C science personnel, please report status immediately.

Sector D Administration

 * Emergency cleanup team to Biological Waste Processing Plant.
 * Attention administration personnel, evacuate Sector D immediately.
 * Attention, security personnel to Sector D.
 * Service team, check Elevator 1, Sector C.
 * Warning, unauthorized biological forms detected in ventilation system.
 * Lieutenant Backman and cleanup team to Sub-Level 3.
 * Danger, turret defense systems activated, Sector D.
 * Security officer reports men down in Sector D, medical help required.
 * Extreme danger, all turret defense systems activated, Sector D.
 * Repair personnel to High Security Materials Storage Area.
 * Attention. Electric shock hazard detected in Administration Center.
 * Security officer reports medical emergency, Administration Center.

Sector D High Security Storage Facility

 * Attention. All science personnel report topside for immediate questioning.
 * All personnel evacuate High Security Materials Storage Facility.
 * Emergency Uranium Containment Team to Sector D.
 * Turret maintenance team to Central Command and Communications Center.
 * Military personnel, prosecute Kilo-India-Lima with extreme force.
 * Attention. This announcement system is now under military command.
 * Search and Destroy Force Bravo reports secondary objective terminated.
 * Bravo Force reports Hotel-Sierra-Mike facility is secured.
 * Attention. All military personnel, atomic-biological-chemical alert.
 * Attention. All military personnel, extreme atomic-biological-chemical alert.
 * Attention. Black Mesa Announcement System is now under military command.

Silo D Experimental Propulsion Labs

 * Attention. Experimental rocket test fire disengaged.
 * Repair crew report to Track Control, Sector E.
 * Maintenance Team Blue, check heat exchange coolant level.
 * Maintenance Team Green, check voltage on Cable 729.
 * Medical Team to Materials Storage Facility, Team Bravo reports men down.
 * Alpha Force move out, science personnel resistance extreme.
 * Attention. All Black Mesa security personnel wanted for immediate questioning.
 * Attention. Gordon Freeman, report to military personnel for immediate security check.
 * Warning, hostile biological forms detected in Track Control, Sector E.

Sector E Track Control

 * Warning. Track power failure. Check lower level power plant.
 * Maintenance team yellow, please service Relay-394.
 * Attention. Gordon Freeman, report to military personnel for immediate security check.
 * Delta team reports Launch Control secured.
 * Danger, turret defense systems activated, Silo E.
 * Sector E Track Control, please report status.
 * Echo force reports perimeter breach, Sector E.
 * Attention, Search and Destroy Force go to Code 3. Eliminate all biological forms.
 * Danger, unauthorized detonation detected in Experimental Propulsion Lab.
 * (only if tram is approached during Gargantua scene) Main power is not on.

Silo E Launch Control

 * Attention, clear Silo E launch area immediately.
 * Containment inspection team to Advanced Biological Research Lab.
 * Medical team to Sector E, Echo Team has men down.
 * Alert military personnel, authorized to prosecute Gordon Freeman with extreme force.
 * Alert military personnel, you are authorized to shoot the renegade on sight.
 * Alert, squad in Silo E, Freeman may be operating inside your perimeter.
 * Launch Control train activity detected.
 * Medical team to Sector E, Echo Team squad failed to reach checkpoint.
 * Satellite Rocket Loading Bay reports status green.
 * (only if exit is walked into) Emergency blast door/shield activated.

Biological Waste Processing Plant & Advanced Biological Research Lab

 * Warning. Emergency containment system activated.
 * Alert! Biological containment breach detected.
 * Warning, biological sterilization system activated.
 * Attention, hostile alien military force detected, Advanced Biological Research Lab.
 * Search and Destroy Force reports backup required, engaged with extreme resistance.
 * Topside Containment Force alert, hostile alien military force detected.
 * High Power Laser status is green.
 * Alien containment system failure, use sterilization chamber.
 * Attention. All topside military personnel, clear Helicopter Hangar 4.
 * Alien breach, Topside Checkpoint Alpha, Checkpoint Delta
 * Alert Topside Containment Force, use any force to prosecute Gordon Freeman. You are authorized to shoot on sight.
 * Alert Topside Containment Force, Freeman may approach your perimeter.
 * Gordon, all science personnel will be terminated until you surrender.

Central Command and Communications Center

 * Warning, Primary Antenna failure detected.
 * Clear Topside Motorpool for emergency medical helicopter.
 * Warning, Topside Armory security bypass detected.
 * Warning, radiation leak detected in Primary Antenna area.
 * Search and Destroy Force Kilo, Central Command reports hostile alien force inside perimeter.
 * Message for Gordon Freeman, you will not escape this time.
 * Attention all units, renegade Freeman is now your primary target.
 * Alert remaining containment force, Freeman may have experimental weapon.
 * All personnel evacuate Lambda Complex, extreme dimensional malfunction detected.
 * Fire Control Team to Topside Armory, Checkpoint Delta, Topside Hydro Plant.

Lambda Reactor Complex, Main Reactor Facility & Hazardous Materials Handling Bays

 * Warning, cross-dimensional power field activity detected
 * Warning, unauthorized biological force detected in cross-dimensional power field.
 * All personnel evacuate Lambda Complex, extreme dimensional malfunction detected.
 * Unauthorized activity detected in Main Reactor Core.
 * Danger, high energy exchange detected in Radioactive Materials Handling Bay.
 * Biological force detected in Primary Coolant System.
 * Lambda Complex reports dimensional contamination.
 * Lambda Complex reports dimensional containment system failure.
 * Warning, Cross-Dimensional Portal Device power level is 120%.
 * Attention Lambda Complex personnel, Primary Core activated.
 * (if supply door near level A ladder is touched) 1. Sorry, this door is inoperative. 2. Door damage detected. Please call service personnel.

Opposing Force

 * Immediate medical attention required in Sector 27.
 * Operations personnel report to Emergency Control Zone for contamination cleanup, Alpha-7 access required.
 * Attention, Supply Team required in Lower Maintenance Chamber Sub-Sector B.
 * Security breach detected in Silo 32.
 * Warning, extreme radiation leak detected in Reactor core 8. Time to reach minimum safe distance: 14 minutes.
 * Dr. Guthrie, report to Inspection Lab 6 immediately.
 * Attention, Dr. Freeman report to Research Administration Center for questioning.
 * Remaining science personnel, report to Medical Lab 6 for radiation exposure inspection.
 * Warning, severe damage detected in ventilation systems under Research Lab 2, evacuate area immediately.

Blue Shift

 * Warning, main power failure in Levels 3, 5 and 8.
 * Warning, extreme electromagnetic field hazard in Sector C.

Decay

 * Attention. Dr. Freeman, report to Anomalous Materials lab.
 * Dr. Cross and Dr. Green, you are required in the Anomalous Materials operations center.
 * All security personnel, check clearance with Inspector White.
 * Attention Science Team, decontamination required in Anomalous Materials lab.
 * Attention. Topside leave has not been authorized with administration.
 * Warning. Do not deactivate containment field systems.
 * Announcement. Topside satellite communication dish has been disengaged.
 * Laser containment system access is forbidden to inspection personnel.
 * Announcement. Waste disposal control will proceed at 135.
 * Anomalous Materials test not open to unauthorized personnel.
 * Attention. All science personnel evacuate Level 3 immediately.
 * Attention. This announcement system now under military command.
 * Attention. Black Mesa Announcement System now under military command.
 * Attention. Science Team, report to nearest security checkpoint immediately.
 * Attention all military personnel, intruder detected in Level 3.
 * Attention. All science personnel report to north transportation platform immediately.
 * Warning. Unauthorized biological forms detected in ventillation system.
 * Charlie Team reports Bravo Foxtrot Johnson facility is secured.
 * Search and destroy squad alpha, reports secondary objective terminated.

Half-Life
''Good morning and welcome to the Black Mesa Transit System. This automated train is provided for the security and convenience of the Black Mesa Research Facility personnel. The time is 8:47 AM. Current topside temperature is 93 degrees with an estimated high of 105. The Black Mesa Compound is maintained at a pleasant 68 degrees at all times. This train is inbound from Level 3 Dormitories to Sector C Test Labs and Control Facilities. If your intended destination is a high-security area beyond Sector C, you will need to return to the central transit hub in Area 9 and board a high-security train. If you have not yet submitted your identity to the retinal clearance system, you must report to Black Mesa personnel for processing before you will be permitted into the high-security branch of the transit system. A reminder that the Black Mesa Hazard Course Decathlon will commence this evening at 1900 hours in the Level 3 facility. The semi-finals for high-security personnel will be announced in a separate, secure-access transmission. Remember: more lives than your own may depend on your fitness. A reminder to all Black Mesa personnel: regular radiation and biohazard screenings are a requirement of continued employment in the Black Mesa Research Facility. Missing a scheduled urinalysis or radiation checkup grounds for immediate termination. If you feel you have been exposed to radioactive or other hazardous materials in the course of your duties, contact your Radiation Safety Officer immediately! Work safe. Work smart. Your future depends on it. Due to the high toxicity of material routinely handled in the Black Mesa Compound, no smoking, eating or drinking are permitted within the Black Mesa transit system. Please keep your limbs inside the train at all times. Do not attempt to open the doors until the train has come to a complete halt at the station platform. In the event of an emergency, passengers are to remain seated and await further instruction. If it is necessary to exit the train, disabled personnel should be evacuated first. Please stay away from electrified rails and proceed to an emergency station until assistance arrives. Do you have a friend or relative who would make a valuable addition to the Black Mesa team? Immediate openings are available in the areas of Materials Handling and low-clearance security. Please contact Black Mesa personnel for further information. If you have an associate in the background of Theoretical Physics, Biotechnology or other high-tech disciplines, please contact our Civilian Recruitment Division. The Black Mesa Research Facility is an equal opportunity employer. Now arriving at Sector C Test Labs and Control Facilities. Please stand back from the automated door and wait for the security officer to verify your identity. Before exiting the train, be sure to check your area for personal belongings. Thank you and have a very safe and productive day.'' (Note: the order of the sound clips may be incorrect, since it is not written)

Blue Shift
''Good morning and welcome to the Black Mesa transit system. This automated train is provided for the comfort and convenience of Black Mesa residents and visitors to the Black Mesa Research Facility. The time is 8:42 AM. Current topside temperature is 91 degrees with an estimated high today of 105. The Black Mesa Compound is maintained at 68 degrees at all times. This train is inbound from the Area 8 Topside Dormitories to the Central Transit Hub in Area 9. Please keep your limbs inside the train at all times. Do not attempt to open the doors until the train has come to a complete halt at the station platform. In the event of an emergency, passengers are to remain seated and await further instruction. If it is necessary to exit the train, disabled passengers should be evacuated first. Please stay away from electrified rails and proceed to an emergency station until assistance arrives. If your intended destination is a high-security area beyond Sector C, you will need to board a high-security train in the Central Transit Hub. If you have not yet submitted your identity for the retinal clearance system, you must report to Black Mesa personnel for processing before you will be admitted to the high-security branch of the transit system. If you wish to transfer to the Sector B or C medium-security lines, you may do so before you reach the Central Transit Hub, at the Area 9 Security Checkpoint. Access to the medium-security branch of the transit system is for employees of the Black Mesa Research Facility and authorized visitors ONLY and requires that you wear your security badge at all times... This train is now transferring to the Sector C line of the transit system. This is a medium security area of the Black Mesa Facility. Be sure to wear your identification badge at all times. Now arriving at Area 3 Security Facilities. Please stand back from the automated door until it has fully opened. Before exiting the train, be sure to check your area for personal belongings. Thank you, and have a safe and productive day!''

Note: This announcement is not heard every time. It may be skipped as the next map loads.

Opposing Force
[sparks, randomly changing speed and pitch through the whole clip] This train is inininbound from frorom [garbled] Seccttorr Cccc... Please keep your legs ininiinside the train at all times. [garbled] ''have an associate with a background in the areas of theothethetheoretical physicssss, biotecchhnology, or other high tech didididisciplines? Please contact our Civilian Recruitment Di-didivision. A rerere- [spark] reminder to all Black Mesa personnenel. [garbled] Regular radiation and biohazard s-ss-sc-screenings are a requirement of continued employment in the in the in thethe- in the Black Mesa Research Facility. Dododo not- do not attempt to open the dodoors until the trai-i-i-i-in has come to a complete halt at the attheattheatthe- [garbled] station platform. Now arriving a-a-at'' [garbled]

Behind the scenes

 * While referred to several times as "Black Mesa Announcement System", it was originally known as "Automatic Diagnostic and Announcement System", as heard in an unused sound file, "vox_login.wav".
 * Kathy Levin, who provided the female voice for the Black Mesa Announcement System, also voiced Gina Cross. This suggests Cross herself might have recorded it, although this might just be related to game limitations.

Trivia

 * Half-Life 2’s equivalent is the Breencast, and informally the Overwatch Voice.
 * Portal’s equivalent is the Aperture Science Speaker System.