Red alert
Red alert, also known as condition red or code red, was the highest alert signal status on Starfleet vessels and starbases.

Usage 

One stage above a yellow alert, this status had weapons systems and shields brought to full , essentially preparing the ship for combat. () 

The Klingon equivalent of this status was defense condition one. ()

The Pakled equivalent of a red alert was called red alarm. ()

Red alert could also be ordered during various other emergency situations, such as a ship being boarded, radiation exposure, a security alert, massive systems failure, an imminent warp core breach, an evacuation order, and a viral medical emergency, among others. (; ; ; ; )

A red alert could either be activated manually by the commanding officer or the officer in charge, or automatically, as when a ship was attacked, entered a dangerous area, et cetera. () 

The raising of shields automatically triggered a red alert. () 

The ability to activate red alert could apparently also be granted even to non-ranking crewmen at discretion, as Seven of Nine had clearance to place the  on red alert. ()

Engaging self-destruct automatically triggers red alert and can only be deactivated by the captain using command codes.  (; ; ; ; ; )

Sections of a starship could be placed on red alert while other sections remained at a lower alert status. ()

Notable uses
In 2152, "condition red" was among several possible names that Lieutenant Malcolm Reed considered for a security protocol that was eventually dubbed "tactical alert". Because of Reed having an obsession with the security protocol,  suggested "Reed Alert", which was also rejected by Reed. ()

In 2266, upon discovering a phaser on overload hidden somewhere in his quarters on the , Captain Kirk announced a "double red alert". ()

In 2287, Commander Chekov placed the  on red alert when Captain Klaa cloaked his Bird-of-Prey. () 

In 2293, while the  was returning from Rura Penthe, an intercom message by Commander Uhura informed the crew that only certain decks should remain on red alert while in Klingon space. ()

During the Battle of Wolf 359, the USS Saratoga went to Red alert before attacking Locutus' cube. {)

In 2369, Commander Benjamin Sisko ordered a red alert for Deep Space 9 when an alien ship from the Gamma Quadrant fired a radiation burst onto the shields, which depolarized them. ()

The same year, Sisko ordered a red alert when a pulse wave torpedo was fired into a subspace rupture. ()

In 2372, Captain Sisko ordered a red alert on the , shortly before the cloaking device was deactivated and the shields raised to prepare for battle with three Klingon Birds-of-Prey. ()

In 2373, the Enterprise-E went to Red Alert before heading to Earth to assist the rest of Star fleet at the Battle of Sector 001. ()

In 2374, Chakotay mentioned that the  would remain on "full" red alert. ()

Later that year, the  went to red alert when it was attacked, and subsequently destroyed, by a Cardassian destroyer unit. ()

Alarm sounds
In addition to dimming of the lights and computer terminals displaying red graphics, an audible alarm would sound. 
 ()
 ()
USS Enterprise (Refit) ()
, and  ()
 ()
Deep Space 9 ()
A  runabout ()
 ()
 and  ()

Appendices

Background information
"Red alert" comes from the naval tradition of general quarters, and, in fact, the command "general quarters" could be used interchangeably to bring the ship into red alert. In , red alert is referred to as both "condition alert" and "general alert". In , Captain Jean-Luc Picard issues both commands.

The uses of red alert were preceded by double red alert being mentioned in . The first produced episode to mention red alert was , which, in airing order, was preceded by a reference to it in . In the final draft script of "Court Martial", double red alert was used extensively instead of red alert, indicating that double red alert developed into this alert status. Scripted references to red alert in the same final draft teleplay were evidently later changed to yellow alert.

In , the red alert lights changed during the show's run. The first time red alert was heard was in , but the lights weren't flashing red. The first time the lights were seen flashing red was in , which had only the top and bottom part of the lights flashing. However, beginning in , all of the lights flashed. The next change in the lights was seen in , in which there was a longer period between when it flashed and when the sound was heard.

External links

de:Roter Alarm
fr:Alerte rouge
ja:非常警報
nl:Rood alarm
Alerts