Security alert A security alert was a type of alert signal aboard starship s and space station s , primarily for internal security purposes . It was similar to an intruder alert , and could be initiated explicitly by personnel or triggered by predefined parameters . In the 23rd century , a security alert aboard Federation starships was part of the general quarters alert , and had at least three levels . ( ) By 2285 , security alerts of Federation starship systems such as the were separated from the general quarters alert . ( ) In the 24th century aboard and starships , security alerts had at least five levels of application ( also referred to as conditions ) , each one for different types of situations . On certain space stations , security alerts were distinguished by color . A security alert could be activated with no stated degree . The ship ' s Security Chief was responsible for initiating shipboard security alerts . ( ) Levels / Conditions . Level / Condition 10 . Aboard the , Captain Kathryn Janeway instituted a level 10 security alert after more former Maquis members now part of her crew were subdued by an unknown assailant . The action also confined non - essential personnel to quarters , and the posting of security team s on all deck s . ( ) Level / Condition 4 . Aboard the Federation starship , Captain Jean - Luc Picard ordered a level 4 security alert in 2369 after it became apparent that crew members were mysteriously disappearing from the vessel . ( ) Around stardate 46731 , the " Enterprise - D " was on level 4 security . ( ) Level / Condition 3 . Picard asked Worf to maintain a level 3 security alert after Lieutenant Reginald Barclay reported seeing alien lifeform s while in an extended transporter beam . ( ) Picard once again instituted a condition 3 security alert and told the computer to shut down all transporter systems and shuttlebay s as Wesley Crusher eluded the crew while they were under the influence of the Ktarian game . ( ) Tuvok called a level three security alert aboard " Voyager " and told all hands to report to duty station s in an attempt to apprehend the mutating Tom Paris . ( ) Level / Condition 2 . In 2369 , Picard ordered a level 2 security alert , after it was learned that a faction of the Borg had changed their entire existence and a new objective . They were no longer interested in acquiring cultures and technology . Armed guards were posted on every deck . ( ) " In an alternate timeline created by Q , Picard ordered a level 2 security alert in 2364 after he continued to experience shifting through time . " ( ) Level / Condition 1 . Geordi La Forge , seemingly filling in for Worf as security chief , suggested the " Enterprise " should go to level one security alert while trying to apprehend the devolving Klingon . ( ) Colors . Yellow . Benjamin Sisko told Kira Nerys to go to security alert yellow when the " Norkova " started dock ing . ( ) Full alert . Commander William T . Riker called for a full security alert when criminals inhabiting three of the " Enterprise " crew ' s bodies attempted to gain control of the ship . ( ) Sisko put the entire station at full security alert , and also ordered for all turbolift s secured and to seal off some airlock s . ( ) Captain Janeway told Chakotay to put " Voyager " into full security alert in response to the newly realized threat from the Vaadwaur . ( ) General alerts . Picard called for a security alert to all decks when Ira Graves , who took over the body of Data , attempted to take over the " Enterprise " . ( ) Worf told the bridge to institute a security alert when he found Singh dead in engineering . ( ) Chief Miles O ' Brien was interrupted while attempting to call a security alert by an alien intruder in Transporter Room Three . Worf expanded the alert to all decks after the intruder left the transporter room . ( ) Picard told Worf to be on security alert when he realized the potential danger of Clara Sutter ' s imaginary friend . ( ) Data called for a security alert as a mercenary ship fled from the " Enterprise " . ( ) Riker called a security alert to all decks when alien intruders were expected to transport aboard the " Enterprise " . ( ) Altovar triggered a security alert when he broke into the infirmary of Deep Space 9 . ( ) While Tieran had control over Kes ' body , Janeway called a security alert as Tieran tried to escape from " Voyager " . ( ) When Chakotay realized that the translocation by the Nyrian s to the was most likely a ploy to take control of the ship , he issued a security alert to all hands , though there were only twelve other crewmen on board at the time . ( ) Ensign " Gentry " tried to call a security alert to " Headquarters " . ( )