The transporter room was part of a starship or space station which was specially outfitted to transport lifeforms and small, inanimate objects. This room included a transporter chamber with a transporter platform.
The number of transporter rooms varied per ship or station, the main criteria being the ability to evacuate all personnel within a specified time. All key components which were needed for transport were fitted in this room and the one just below.
Some starships, such as the NX-class Enterprise NX-01, did not have a transporter room. The area surrounding the transporter was instead situated between two corridors to which the transporter alcove was directly adjoined, on either side. (ENT: "The Andorian Incident")
A transporter room was usually manned by a transporter chief. Miles O'Brien was the senior transporter chief for much of the USS Enterprise-D's service. Transporter room three was O'Brien's preferred room. As he left to take up his post on Deep Space 9, Jean-Luc Picard told him it would not be the same without him. (Star Trek: The Next Generation; DS9: "Emissary")
Although Deep Space 9 was equipped with at least five transporter rooms, Ops had its own transporter. (DS9: "Dramatis Personae", "Things Past") The DS9 Ops transporter was also used, several times, to effect a doorway to the mirror universe. (DS9: "Through the Looking Glass", "Shattered Mirror", "Resurrection")
Rooms and uses
USS Enterprise NCC-1701
USS Enterprise NCC-1701-D
Transporter room 1 was located on deck 6, room 1654. (TNG: "Brothers") It served as a mass evacuation transporter for decks 5 to 10. (TNG: "11001001") For decks 1 to 4, mass evacuation occurred via the cargo transporters. (TNG: "11001001")
In 2364, Lieutenant Natasha Yar requested Commander William T. Riker's presence in transporter room 1. His presence was needed for an inspection of an unidentified item being beamed in from a surface station on Haven. With Riker present, a Betazoid gift box materialized on the transporter pad. Later, Counselor Deanna Troi, when entering the room, expressed dismay at the sight of the gift box. (TNG: "Haven")
In 2366, this transporter room was used in an attempt to transport Roga Danar from the brig to an Angosian police shuttle. He managed to escape the transport attempt while making himself appear to have been lost in an explosion. (TNG: "The Hunted")
Transporter room 2 was located on deck 6. It also served as a mass evacuation transporter for decks 5 to 10. (TNG: "11001001") In 2368, Cadet Wesley Crusher was beamed over to the USS Merrimac from this room. (TNG: "The Game")
Transporter room 3 was located on deck 6, room 2054. It also served as a mass evacuation transporter for decks 5 to 10. This was Chief O'Brien's favorite transporter room on the ship. (TNG: "11001001"; DS9: "Emissary") Propulsion expert Kosinski and his companion, The Traveler, were beamed aboard the Enterprise-D from the USS Fearless into this room. Greeting the visitors were Commander Riker, Counselor Troi, and Chief Engineer Argyle. (TNG: "Where No One Has Gone Before")
After speaking with Doctor Beverly Crusher and Counselor Troi about a brain graph of Captain Jean-Luc Picard in 2364, Commander Riker requested the computer for a location of the captain. The computer located the captain's last position as transporter room 3. Before Riker could order a shutdown of transporter controls, Picard, under the influence of the thought maker, had beamed to his prior command, the USS Stargazer. (TNG: "The Battle")
After a rescue-and-recovery team led by Commander Riker and consisting of Lieutenant Commander Data and Lieutenant Geordi La Forge had located survivors, led by the Klingon officer Korris, aboard the freighter Batris, Captain Picard ordered Lieutenant Yar to this room to greet the away team. For the retrieval of the away team, plus three Klingons, she operated the transporter controls. (TNG: "Heart of Glory")
After Commander Riker was encased in a force field on Minos, Captain Picard asked the transporter chief of this room if he had a lock on the away team. He replied that he had a lock on two members of the team, but not Riker. After conferring with his senior officers, the captain and Doctor Crusher beamed down to the planet's surface from this room. (TNG: "The Arsenal of Freedom")
In early 2365, Data authorized the transporter chief, Miles O'Brien, to transport samples of plasma plague from 'aucdet IX into cargo deck 5, a cargo bay situated in the stardrive section of the Enterprise-D. Later in this room, in orbit of Science Station Tango Sierra, O'Brien transported the samples from the bay into a contained area on the space station. (TNG: "The Child")
After a terrorist bombing at the Lumar Cafe on Rutia IV in 2366, Captain Picard ordered the transporter chief to target Dr. Crusher, Lt. Cmdr. Data, and Lt. Worf, and prepare for an immediate beam-up. However, before the transportation could take effect, Crusher was kidnapped by the Ansata.
A few days later, in a brazen attack on the Enterprise-D, the Ansata planted a bomb on the main reactor chamber. Captain Picard ordered the transporter chief to lock onto the explosive device and beam it out into space. As the bomb had sensor jamming technology, the chief couldn't complete the order. It was only when Lt. Cmdr. Geordi La Forge removed the bomb from the chamber with a laser cutter and placed his communicator on the bomb that the transportation could take effect. As per the chief engineer's instructions, the bomb materialized five kilometers off the starboard nacelle, where it exploded harmlessly. (TNG: "The High Ground")
Upon the chance discovery of an one-man spaceship crashed on a planet in the Zeta Gelis star cluster, a medical triage team led by Riker, and consisting of Dr. Crusher, Lt. Cmdr. Data, and La Forge, were beamed near to the crash site by the transporter chief in this room. (TNG: "Transfigurations")
While trapped in a temporal fragment in 2369, the Enterprise-D beamed several Romulans on board. The away team, including Captain Picard, Deanna Troi, Data, and Geordi La Forge tried to find out what happened and beamed on board the Enterprise-D. Picard ordered Troi to go to sickbay, Data to main engineering, and himself to transporter room 3, where he found Worf and two security officers who beamed three Romulans on board. (TNG: "Timescape")
Transporter room 4 also served as a mass evacuation transporter for decks 5 to 10. (TNG: "11001001") In late 2364, a rescue-and-recovery team led by Commander Riker and consisting of Dr. Crusher, Data, and Yar beamed from this room to Vagra II in an effort to rescue survivors of a shuttle crash. (TNG: "Skin of Evil") In 2366, this room was also used to beam Roga Danar on board from an escape pod. (TNG: "The Hunted")
Transporter room 5 served as a mass evacuation transporter for decks 6 to 16. (TNG: "11001001") In 2365, Chief Miles O'Brien was assigned to this room. He transported Jean-Luc Picard, Deanna Troi, and Worf to Ramatis III. (TNG: "Loud As A Whisper")
Transporter room 6 also served as a mass evacuation transporter for decks 6 to 16. (TNG: "11001001") In 2364, the transporter chief for this room reported a transporter console malfunction to the bridge. The malfunction was later attributed to an entity found in the Beta Renner cloud. (TNG: "Lonely Among Us")
Transporter room 8 was located on deck 12. (TNG: "Coming of Age") It was used for mass evacuation of decks 6 to 16. (TNG: "11001001") In 2364, Wesley Crusher, on his way to the Starfleet Academy entrance exams, was beamed to Relva VII from this room. Captain Picard, Commander Riker, and Lieutenant Yar wished him well, and his mother, Dr. Crusher, gave him a hug expressing her pride and love. Later, the four officers greeted Admiral Gregory Quinn and Lieutenant Commander Dexter Remmick of the Judge Advocate General as they beamed in from the planet. (TNG: "Coming of Age")
USS Enterprise NCC-1701-E
In 2373, transporter room 3 beamed the crew of the USS Defiant aboard when the ship's life support system failed. Later, the away team including Captain Picard, Data, and Beverly Crusher was beamed from this transporter room to Bozeman, Montana. (Star Trek: First Contact)
The USS Voyager had at least three transporter rooms.
In 2372, transporter room 2 was used to retrieve samples of an irregular comet, only to beam aboard Quinn, a member of the Q Continuum. (VOY: "Death Wish") Later that year, Kathryn Janeway requested that engineering shunt available power to transporter room 2 in order to retrieve Tom Paris. (VOY: "Investigations")
Gallery of transporter rooms
The script of TOS: "The Cage", the first Star Trek pilot episode; described the transporter room by stating, "Completely unlike any other station on the Enterprise, the Transporter Room is heavily shielded." The script then continued by describing several of the room's contents, which were generally far different from those seen in the episode's final version. These included a strange device dominating the room, a "glassed-in" transporter chamber hovering over the device, and a hooded viewing screen that the transporter operator could peer into to determine where the transporter subject was being beamed to.
The first scenes ever shot for Star Trek were originally set to be in the Enterprise's transporter room. The set was on Stage 16 of Desilu's Culver City lot. However, the filming schedule was changed and the very first scene shot was actually in Captain Pike's quarters. (Inside Star Trek: The Real Story, pp. 43-46) 
The TOS transporter room set was situated on Desilu Stage 9. (Star Trek: The Magazine Volume 1, Issue 17, p. 13) According to Star Trek: The Magazine Volume 1, Issue 17, p. 13), the set was never redressed, during production on the series, and Robert Justman noted, "Common sense mandated leaving this one alone." According to The Star Trek Compendium (4th ed., p. 40), however, the set was redressed to serve as the Enterprise's chapel in the episode "Balance of Terror".
The transporter room underwent a slight redesign for the ultimately abandoned series Star Trek: Phase II. In August 1977, while the updated set was due to be constructed on Paramount Stage 9, Joe Jennings began work on re-envisioning the room. (Star Trek Phase II: The Lost Series, p. 37) Some conceptual illustrations of the revised transporter room were created by Mike Minor. (The Art of Star Trek, p. 63) On 8 September 1977, producer Robert Goodwin sent a memo to Gene Roddenberry which included the statement, "The shell for the transporter room is being built. Soon Mike Minor will have sketches ready for you to approve on the look of the new transporter room." (Star Trek Phase II: The Lost Series, pp. 43-44) In a March 1978 interview, Susan Sackett reported the transporter room as having an "orange motif." (Starlog #12) The writers/directors guide for Phase II included the statement, "We assume there are various Transporter Rooms through the vessel," and suggested that the Enterprise's chapel be a redress of the transporter room set. (Star Trek Phase II: The Lost Series, pp. 93 & 94) Similarly, the first-draft script of "In Thy Image" proposed that Phase II's regular transporter room be redressed to serve as the transporter room of another starship in that story, the light cruiser Delphi. (Star Trek Phase II: The Lost Series, pp. 210 & 214)
A wall section of the Enterprise's transporter room that was built for Star Trek: Phase II went on to be used as part of both the starship's sickbay in Star Trek: The Motion Picture, and the ship's transporter room in Star Trek II: The Wrath of Khan. (text commentary, Star Trek: The Motion Picture (The Director's Edition) DVD; Star Trek: The Next Generation - The Continuing Mission, p. 33) Following its reuse in the latter film, the same set piece additionally appeared in the Galaxy-class transporter room of Star Trek: The Next Generation as well as the Intrepid-class transporter room of Star Trek: Voyager. (text commentary, Star Trek: The Motion Picture (The Director's Edition) DVD)
More than any other set in Star Trek: The Motion Picture, the Enterprise transporter room fascinated the film's production designer, Harold Michelson. (The Making of Star Trek: The Motion Picture, p. 91) He designed the revamped appearance of the room for the film, situating the transporter operators in a shielded control compartment in an attempt to convey the extraordinary energies involved in the transporter's operation. (The Art of Star Trek, p. 164; The Making of Star Trek: The Motion Picture, pp. 91-92) The set for The Motion Picture's transporter room was built on Stage 9. (The Making of Star Trek: The Motion Picture, p. 95) The floor of that transporter room included a segment consisting of many complex conduits, which was actually a sheet of vacuum-formed plastic, the shape of which was reused as wall panels in the Enterprise-class Mark IV bridge simulator in Star Trek II: The Wrath of Khan. (text commentary, Star Trek II: The Wrath of Khan (The Director's Edition) DVD) For The Motion Picture, the appearance of the transporter room's complex of machinery was enhanced by cinematographer Richard Kline, using some eerie-looking lighting. (The Making of Star Trek: The Motion Picture, p. 92) Following production on The Motion Picture, the set for the film's transporter room was planned to be stored "indefinitely." (The Making of Star Trek: The Motion Picture, p. 214)
The Galaxy-class transporter room was designed by illustrator Andrew Probert and production designer Herman Zimmerman, who deliberately echoed the layout of the TOS transporter room to appease hardcore fans of the original series. (Star Trek Monthly issue 19, p. 40)
In Star Trek V: The Final Frontier and Star Trek VI: The Undiscovered Country, the transporter room was a redress of the Enterprise-D's transporter room from TNG. (text commentary, Star Trek VI: The Undiscovered Country (Special Edition) DVD)
The fact that no transporter rooms were aboard runabouts used on Star Trek: Deep Space Nine was one of multiple factors that led to the conceptual invention of the USS Defiant. At a point when no transporter room had yet been designed for the ship, Herman Zimmerman foresaw that, as story lines warranted them and the producers budgeted for them, transporter facilities would be added to the set for the vessel. (Cinefantastique, pp. 108 & 97) A Defiant-class transporter bay was thereafter introduced in DS9: "Past Tense, Part I".
The Star Trek: Voyager Technical Manual states that the Intrepid-class USS Voyager has only two transporter rooms, as opposed to the three such rooms established in canon.  The Intrepid-class transporter room was built on virtually the same space previously occupied by the equivalent room for TNG's Enterprise; both were on Paramount Stage 9. (The Official Star Trek: Voyager Magazine issue 1, pp. 68-69) Production Designer Richard James kept the floor and ceiling, though he redesigned everything else to conform with the other Intrepid-class interior sets, almost entirely changing the "look" of the transporter room. Commented Michael Okuda, "You can still see the bloodlines... same nose, same ears... the same family genes." A set of construction blueprints for the Intrepid-class transporter room set was illustrated, initially dated 8 June 1994 but revised on four subsequent occasions in that month. The wood had been recycled through usage in sets for various earlier starships. (A Vision of the Future - Star Trek: Voyager, pp. 244 & 245) The set was repainted and redressed to represent a Sovereign-class transporter room in Star Trek: Insurrection. (Star Trek: The Next Generation Companion (3rd ed., p. 341))
For the alternate reality Enterprise, the transporter room was specifically designed to elicit a sense of exit from the ship. "The transporter room has an airlock feeling, it's physically separated in case something goes wrong," concept artist Ryan Church commented. "It felt functional that way." (Star Trek - The Art of the Film, p. 104) For the film Star Trek, the transporter room set was built on Paramount Stage 15. (Star Trek Magazine issue 145, p. 76) The set was one of several which, after production on the Star Trek film wrapped, were disassembled into segments that were stored away until Star Trek Into Darkness entered production, when the set pieces were polished, rebuilt and tweaked. "In the transporter bay, we changed the effect of the glass pieces that ring that bay," said Production Designer Scott Chambliss. "I wasn't terribly happy with how it looked on film in the original one." (Star Trek Magazine issue 172, p. 68) For Star Trek Into Darkness, the transporter room set was built on Sony Stage 15. 
Under the aegis of DIS Season 1 Production Designer Todd Cherniawsky, a concept illustration of the Walker-class transporter room was created for the first season of Star Trek: Discovery, as was a concept drawing of the Crossfield-class transporter room. ("Designing Discovery", DIS Season 1 DVD and Blu-ray special features)
In The Worlds of the Federation (p. 16), the USS Moscow's transporter room is said to have been the site of the first transporting of a Human. The book also describes that transporter room as being located at the UFP Aerospace Museum-Smithsonian Annex and a "recent acquisition" there.