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139-553: 7 World Trade Center ( 7 WTC , WTC-7 , or Tower 7 ), colloquially known as Building 7 or the Salomon Brothers Building , was an office building constructed as part of the original World Trade Center Complex in Lower Manhattan , New York City . The tower was located on a city block bounded by West Broadway , Vesey Street , Washington Street , and Barclay Street on the east, south, west, and north, respectively. It

278-540: A fire-resistance rating . The term "fireproofing" may be used in conjunction with standards, as reflected in common North American construction specifications. An item classed as fireproof is resistant in specified circumstances, and may burn or be rendered inoperable by fire exceeding the intensity or duration that it is designed to withstand. Asbestos was one material historically used for fireproofing, either on its own, or together with binders such as cement , either in sprayed form or in pressed sheets, or as additives to

417-807: A 1970 account was supposed to accommodate 130,000 people. On a typical weekday, an estimated 50,000 people worked in the complex and another 140,000 passed through as visitors. The World Trade Center was so large that it had its own zip code: 10048 . The towers offered expansive views from the observation deck atop the South Tower and the Windows on the World restaurant on top of the North Tower. The Twin Towers became known worldwide, appearing in numerous movies and television shows as well as on postcards and other merchandise. It became

556-463: A 362 foot (110 m) telecommunications antenna or mast that was built on the roof in 1979 (upgraded in 1999 to accommodate DTV broadcasts). With this addition, the highest point of the North Tower reached 1,730 feet (530 m). Chicago's Willis Tower , then called Sears Tower which was finished in May 1973 , reached 1,450 feet (440 m) at the rooftop. When completed in 1973, the South Tower became

695-755: A New York icon, in the same league as the Empire State Building, the Chrysler Building, and the Statue of Liberty . The World Trade Center was compared to Rockefeller Center , which David Rockefeller's brother Nelson Rockefeller had developed in midtown Manhattan. One World Trade Center and Two World Trade Center, commonly referred to as the Twin Towers , were designed by architect Minoru Yamasaki as framed tube structures, which provided tenants with open floor plans, uninterrupted by columns or walls. They were

834-488: A business writer, it also was the origin of the electronic component distribution business. The idea of establishing a World Trade Center in New York City was first proposed in 1943. The New York State Legislature passed a bill authorizing New York Governor Thomas E. Dewey to begin developing plans for the project, but the plans were put on hold in 1949. During the late 1940s and 1950s, economic growth in New York City

973-547: A fire (see the hydrocarbon curves in fire-resistance rating ). Where hydrocarbon transports are permitted in tunnel construction and operations, accidental fires may occur, resulting in the need for fireproofing of traffic tunnels with concrete linings. Concrete cannot, by itself, withstand severe hydrocarbon fires. In the Channel Tunnel that connects the United Kingdom and France , an intense fire broke out and reduced

1112-505: A height of 1,377 ft (420 m). On a clear day, visitors could see up to 50 miles (80 km). An anti-suicide fence was placed on the roof itself, with the viewing platform set back and elevated above it, requiring only an ordinary railing. This left the view unobstructed, unlike the observation deck of the Empire State Building. Windows on the World, the restaurant on the North Tower's 106th and 107th floors, opened in April 1976 . It

1251-420: A key girder off its seat, triggering the floors to fail around column 79 on floors 8 to 14. With a loss of lateral support across nine floors, column 79 buckled – pulling the east penthouse and nearby columns down with it. With the buckling of these critical columns, the collapse then progressed east-to-west across the core, ultimately overloading the perimeter support, which buckled between Floors 7 and 17, causing

1390-640: A more effective insulation at a lower cost. The resulting plaster has qualified to the A2 combustibility rating as per DIN4102. Fibrous plasters, containing either mineral wool , or ceramic fibres tend to simply entrain more air, thus displacing the heavy fibres. Proprietary boards and sheets, made of gypsum , calcium silicate , vermiculite , perlite , mechanically-bonded composite boards made of punched sheet-metal and cellulose-reinforced concrete have all been used to clad items for increased fire resistance. An alternative method to keep building steel temperature below

1529-411: A square plan approximately 208 feet (63 m) in dimension on each side. The buildings were designed with narrow office windows 18 inches (46 cm) wide, which reflected Yamasaki's fear of heights as well as his desire to make building occupants feel secure. His design included building facades clad in aluminum-alloy. The World Trade Center was one of the most striking American implementations of

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1668-410: A strong, rigid wall structure, supporting virtually all lateral loads such as wind loads, and sharing the gravity load with the core columns. The perimeter structure containing 59 columns per side was constructed with extensive use of prefabricated modular pieces, each consisting of three columns, three stories tall, connected by spandrel plates. The spandrel plates were welded to the columns to create

1807-457: A term of 30 years. In December 1986, after the Boesky insider-trading scandal, Drexel Burnham Lambert canceled the lease, leaving Silverstein to find other tenants. Spicer & Oppenheim agreed to lease 14 percent of the space, but for more than a year, as Black Monday and other factors adversely affected the Lower Manhattan real estate market, Silverstein was unable to find tenants for

1946-409: A utility shaft that ran vertically between floors. Areas at the furthest extent of the fire were extinguished almost immediately; the original fire was put out in a few hours. Most of the damage was concentrated on the 11th floor, fueled by cabinets filled with paper, alcohol-based fluid for office machines, and other office equipment. Fireproofing protected the steel and there was no structural damage to

2085-521: A variety of materials and products, including fabrics for protective clothing and building materials. Because the material was later proven to cause cancer, a large removal-and-replacement industry has been established. Endothermic materials have also been used to a large extent and are still in use today, such as gypsum , concrete and other cementitious products. More highly evolved versions of these are used in aerodynamics , intercontinental ballistic missiles (ICBMs) and re-entry vehicles, such as

2224-520: Is closer to the site's eastern border. It was on this shoreline, close to the intersection of Greenwich and the former Dey Street , that Dutch explorer Adriaen Block 's ship, Tyger , burned to the waterline in November 1613, stranding him and his crew and forcing them to overwinter on the island. They built the first European settlement in Manhattan . The remains of the ship were buried under landfill when

2363-505: The 1993 World Trade Center Bombing Memorial fountain. The plaza was pervaded by Muzak background music that came from installed loudspeakers. For many years, the Plaza was often beset by brisk winds at ground level owing to the Venturi effect between the two towers. Some gusts were so strong that pedestrians' travel had to be aided by ropes. In 1997 Tony May opened an Italian restaurant in

2502-584: The Space Shuttles . In a building fire, structural steel loses strength as the temperature increases. In order to maintain the structural integrity of the steel frame, several fireproofing measurements are taken: Historically, these masonry encasement methods use large amounts of heavy materials, thus greatly increasing the load to the steel frame. Newer materials and methods have been developed to resolve this issue. The following lists both older and newer methods of fireproofing steel beams ( i-beams ): Among

2641-629: The United States Secret Service (85,343 sq ft/7,900 m). The smallest tenants included the New York City Office of Emergency Management , National Association of Insurance Commissioners , Federal Home Loan Bank of New York, First State Management Group Inc., Provident Financial Management , and the Immigration and Naturalization Service . The Department of Defense (DOD) and Central Intelligence Agency (CIA) shared

2780-551: The World Trade Center site took eight months, during which the remains of the other buildings were demolished. On May 30, 2002, the last piece of WTC steel was ceremonially removed. A new World Trade Center complex is being built with six new skyscrapers and several other buildings, many of which are complete. A memorial and museum to those killed in the attacks, a new rapid transit hub , and an elevated park have opened. The memorial features two square reflecting pools in

2919-468: The framed-tube structural system used in the twin towers. The Port Authority's Engineering Department served as foundation engineers , Joseph R. Loring & Associates as electrical engineers , and Jaros, Baum & Bolles (JB&B) as mechanical engineers . Tishman Realty & Construction Company was the general contractor on the World Trade Center project. Guy F. Tozzoli , director of

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3058-512: The shoreline was extended beginning in 1797 and was discovered during excavation work in 1916. The remains of a second eighteenth-century ship were discovered in 2010 during excavation work at the site. The ship, believed to be a Hudson River sloop , was found just south of where the Twin Towers stood, about 20 feet (6.1 m) below the surface. Later, the area became New York City's Radio Row , which existed from 1921 to 1966. The neighborhood

3197-659: The tallest buildings in the world ; they were also the tallest twin skyscrapers in the world until 1996, when the Petronas Towers opened. Other buildings in the complex included the Marriott World Trade Center (3 WTC), 4 WTC , 5 WTC , 6 WTC , and 7 WTC . The complex contained 13,400,000 square feet (1,240,000 m ) of office space and, prior to its completion, was projected to accommodate an estimated 130,000 people. The core complex cost about $ 400 million (equivalent to $ 2.31 billion in 2023). The idea

3336-477: The 107th floor to the top of the buildings were designed to support a tall communication antenna on top of each building. Only 1 WTC (North Tower) actually had a spire antenna fitted, which was added in May 1979. The truss system consisted of six trusses along the long axis of the core and four along the short axis. This truss system allowed some load redistribution between the perimeter and core columns and supported

3475-432: The 1960s by Bangladeshi-American structural engineer Fazlur Rahman Khan , was a new approach that allowed more open floor plans than the traditional design that distributed columns throughout the interior to support building loads. Each of the World Trade Center towers had 236 high-strength, load-bearing perimeter steel columns which acted as Vierendeel trusses . The perimeter columns were spaced closely together to form

3614-618: The 25th floor with the IRS. (The clandestine CIA office was revealed only after the 9/11 attacks.) Floors 46–47 were mechanical floors , as were the bottom six floors and part of the seventh floor. According to CoStar Group , floors 9 and 10 of 7 WTC were occupied by the Secret Service. The CIA had offices on the 25th floor of 7 WTC, as reported by the Associated Press . The National Institute of Standards and Technology 's 2008 Final Report on

3753-453: The Collapse of World Trade Center Building 7 confirmed that floor 14 was vacant, and updated the news reports of CoStar and Associated Press from 2001 to show that Salomon Smith Barney leased floors 15 to 17. The total amount of space occupied by each tenant was: As the North Tower (1 World Trade Center) collapsed on September 11, 2001, heavy debris hit 7 World Trade Center, damaging

3892-568: The Greatest Bar on Earth and Cellar in the Sky (reopened after Labor Day ) replaced the original restaurant offshoots. In 1999, Cellar in the Sky was changed into an American steakhouse and renamed as Wild Blue. In 2000 (its last full year of operation), Windows on the World reported revenues of $ 37 million, making it the highest-grossing restaurant in the United States. The Skydive Restaurant, which

4031-646: The Hudson River. In a December 1961 meeting between Port Authority director Austin J. Tobin and newly elected New Jersey Governor Richard J. Hughes , the Port Authority offered to take over the H&;M Railroad. They also decided to move the World Trade Center project to the Hudson Terminal building site on the west side of Lower Manhattan, a more convenient location for New Jersey commuters arriving via PATH . With

4170-475: The North Tower within Tobin Plaza for musicians and performers. These series of concerts and events were called "CenterStage at the World Trade Center". At the center of the plaza stood the monumental sculpture The Sphere by German artist Fritz Koenig . The world's largest bronze sculpture of modern times was surrounded by a fountain. The site had other sculptures such as Ideogram , Cloud Fortress , and

4309-447: The Port Authority leased operation of the observatory to Ogden Entertainment, which decided to renovate it. On April 30, 1997, the Top of the World tour reopened after renovations were finished. Attractions added to the observation deck included 24 video monitors, which provided descriptions of 44 points of interest in six languages; a theater showing a film of a simulated helicopter tour around

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4448-512: The Port Authority's approved plans to privatize the World Trade Center in the late 1990s, they sought to lease it to a private entity in 2001. Bids for the lease came from Vornado Realty Trust ; a joint bid between Brookfield Properties Corporation and Boston Properties ; and a joint bid by Silverstein Properties and the Westfield Group . Privatizing the World Trade Center would add it to

4587-409: The Port Authority's chief engineer, John M. Kyle Jr., involved digging a trench, and as excavation proceeded, filling the space with a slurry consisting of a mixture of bentonite and water, which plugged holes and kept groundwater out. When the trench was dug out, a steel cage was inserted and concrete was poured in, forcing the slurry out. It took fourteen months for the slurry wall to be completed. It

4726-494: The Salomon Brothers building. Most of the three existing floors were removed as tenants continued to occupy other stories, and more than 350 tons (U.S.) of steel were added to construct three double-height trading floors. Nine diesel generators were installed on the 5th floor as part of a backup power station. "Essentially, Salomon is constructing a building within a building – and it's an occupied building, which complicates

4865-527: The Secret Service's largest field office were lost, with one Secret Service agent saying, "All the evidence that we stored at 7 World Trade, in all our cases, went down with the building." Copies of emails in connection with the WorldCom scandal that were later requested by the SEC from Salomon Brothers , a subsidiary of Citigroup housed in the building, were also destroyed. The NIST report found no evidence supporting

5004-475: The September 11 attacks, mentions of the complex in various media were altered or deleted , and several dozen "memorial films" were created. The World Trade Center experienced several major crime and terrorist incidents, including a fire on February 13 , 1975; a bombing on February 26 , 1993; and a bank robbery on January 14 , 1998. These events preceded the terrorist attacks on September 11, 2001. During

5143-873: The Structural Engineering Institute of the American Society of Civil Engineers (SEI/ASCE); the Society of Fire Protection Engineers (SFPE); the National Fire Protection Association (NFPA); the American Institute of Steel Construction (AISC); the Council on Tall Buildings and Urban Habitat (CTBUH); and the Structural Engineers Association of New York (SEAoNY). The bulk of the investigation of 7 World Trade Center

5282-560: The Twin Towers, the plan for the World Trade Center complex included four other low-rise buildings, which were built in the early 1970s. The 47-story 7 World Trade Center building was added in the 1980s, to the north of the main complex. Altogether, the main World Trade Center complex occupied a 16-acre (65,000 m ) superblock . The World Trade Center complex housed more than 430 companies that were engaged in various commercial activities. The complex hosted 13,400,000 square feet (1,240,000 m ) of office space, which according to

5421-401: The World Trade Center towers could be subjected to and structural response to those forces. Experiments also were done to evaluate how much sway occupants could comfortably tolerate; however, many subjects experienced dizziness and other ill effects. One of the chief engineers Leslie Robertson worked with Canadian engineer Alan G. Davenport to develop viscoelastic dampers to absorb some of

5560-564: The World Trade Department at the Port Authority, and Rino M. Monti, the Port Authority's Chief Engineer, oversaw the project. As an interstate agency, the Port Authority was not subject to the local laws and regulations of the City of New York, including building codes . Nonetheless, the World Trade Center's structural engineers ended up following draft versions of New York City's new 1968 building codes. The framed-tube design, introduced in

5699-442: The afternoon. At approximately 2:00 pm, firefighters noticed a bulge in the southwest corner of 7 World Trade Center between the 10th and 13th floors, a sign that the building was unstable and might collapse. During the afternoon, firefighters also heard creaking sounds coming from the building. Around 3:30 pm, FDNY Chief of Operations Daniel A. Nigro decided to halt rescue operations, surface removal, and searches along

7 World Trade Center (1987–2001) - Misplaced Pages Continue

5838-467: The architectural ethic of Le Corbusier and was the seminal expression of Yamasaki's gothic modernist tendencies. He was also inspired by Islamic architecture , elements of which he incorporated in the building's design, having previously designed Saudi Arabia's Dhahran International Airport with the Saudi Binladin Group . A major limiting factor in building height is the issue of elevators;

5977-619: The area for the World Trade Center by March 1965, and demolition of Radio Row began in March 1966. It was completely demolished by the end of the year. Approval was also needed from New York City Mayor John Lindsay and the New York City Council . Disagreements with the city centered on tax issues, and the New York City Planning Commission wanted the Port Authority to increase its payments in lieu of taxes (PILOT) to

6116-460: The attacks, al-Qaeda -affiliated hijackers flew two Boeing 767 jets, one into each of the Twin Towers, seventeen minutes apart; between 16,400 and 18,000 people were in the Twin Towers when they were struck. The fires from the impacts were intensified by the planes' burning jet fuel, which, along with the initial damage to the buildings' structural columns, ultimately caused both towers to collapse . The attacks killed 2,606 people in and around

6255-440: The attacks, some from smoke inhalation. Sheikh Omar Abdel Rahman and four other individuals were later convicted for their involvement in the bombing, while Yousef and Eyad Ismoil were convicted for carrying out the bombing. According to a presiding judge, the conspirators' chief aim at the time of the attack was to destabilize the North Tower and send it crashing into the South Tower, toppling both skyscrapers. Following

6394-605: The bathtub began in late 1967. Construction work began on the North Tower in August 1968 , and construction on the South Tower was under way by January 1969 . The original Hudson Tubes , which carried PATH trains into Hudson Terminal, remained in service during the construction process until 1971, when a new station opened. The topping out ceremony of 1 WTC (North Tower) took place on December 23 , 1970, while 2 WTC's ceremony (South Tower) occurred on July 19 , 1971. Extensive use of prefabricated components helped to speed up

6533-409: The bombing, floors that were blown out needed to be repaired to restore the structural support they provided to columns. The slurry wall was in peril following the bombing and the loss of the floor slabs that provided lateral support against pressure from Hudson River water on the other side. The refrigeration plant on sublevel B5, which provided air conditioning to the entire World Trade Center complex,

6672-427: The building to the World Trade Center plaza. The building was situated above a Consolidated Edison power substation, which imposed unique structural design constraints. When the building opened in 1987, Silverstein had difficulties attracting tenants. Salomon Brothers signed a long-term lease in 1988 and became the anchor tenant of 7 WTC . On September 11, 2001, the structure was substantially damaged by debris when

6811-518: The building were used by the New York City Office of Emergency Management , Salomon Smith Barney , and other tenants. In order to supply the generators, 24,000 gallons (91,000 L) of diesel fuel were stored below ground level. Diesel fuel distribution components were located at ground level, up to the ninth floor. The roof of the building included a small west penthouse and a larger east mechanical penthouse. Each floor had 47,000 sq ft (4,400 m) of rentable office space, which made

6950-444: The building's floor plans considerably larger than most office buildings in the city. In all, 7 World Trade Center had 1,868,000 sq ft (173,500 m) of office space. Two pedestrian bridges connected the main World Trade Center complex, across Vesey Street, to the third floor of 7 World Trade Center. In addition to several acquired artworks, from artists such as Frank Stella , Roy Lichtenstein , and Ross Bleckner ,

7089-623: The building) which included floors 28–45. Other major tenants included ITT Hartford Insurance Group (122,590 sq ft/11,400 m), American Express Bank International (106,117 sq ft/9,900 m), Standard Chartered Bank (111,398 sq ft/10,350 m), and the Securities and Exchange Commission (106,117 sq ft/9,850 m). Smaller tenants included the Internal Revenue Service Regional Council (90,430 sq ft/8,400 m) and

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7228-455: The building. They attempted to extinguish small pockets of fire, but low water pressure hindered their efforts. Over the course of the day, fires burned out of control on several floors of 7 World Trade Center, the flames visible on the east side of the building. During the afternoon, the fire was also seen on floors 6–10, 13–14, 19–22, and 29–30. In particular, the fires on floors 7 through 9 and 11 through 13 continued to burn out of control during

7367-544: The buildings would each have to be 110 stories tall. The Port Authority publicly presented a model for the complex on January 18, 1964. The original plans called for two towers rising 1,350 feet (410 m), as well as several six-story buildings surrounding a central plaza (later the Austin J. Tobin Plaza ). These buildings were to include office space, restaurants, a hotel, exhibition space, stores, and an information center about world trade. The agency released its final model of

7506-587: The cause of the collapse and called for further investigation. Subsequently, the National Institute of Standards and Technology (NIST) was authorized to lead an investigation into the structural failure and collapse of the World Trade Center Twin Towers and 7 World Trade Center. The investigation, led by Dr S. Shyam Sunder, drew upon in-house technical expertise as well as the knowledge of several outside private institutions, including

7645-527: The center marking where the Twin Towers stood. One World Trade Center , the tallest building in the Western Hemisphere at 1,776 feet (541 m) and the lead building for the new complex, completed construction in May 2013 and opened in November 2014. The western portion of the World Trade Center site was originally under the Hudson River . The shoreline was in the vicinity of Greenwich Street , which

7784-427: The city called "Manhattan Magic"; a model of Manhattan with 750 buildings; a Kodak photo booth and two gift shops. The 107th-floor also featured a subway -themed food court that featured Sbarro Street Station and Nathan's Famous Hot Dogs with a dining area that simulated Central Park . Weather permitting, visitors could ride two short escalators up from the 107th-floor viewing area to an outdoor platform at

7923-511: The city government. On August 3 , 1966, an agreement was reached whereby the Port Authority would make annual PILOTs for the portion of the World Trade Center leased to private tenants. In subsequent years, the payments would rise as the real estate tax rate increased. In May 1967, the New York City Planning Commission approved several changes to the street grid that would allow the Port Authority to begin acquiring land for

8062-402: The city's tax rolls and provide funds for other Port Authority projects. On February 15 , 2001, the Port Authority announced that Vornado Realty Trust had won the World Trade Center lease, paying $ 3.25 billion for the 99-year lease. Vornado outbid Silverstein by $ 600 million though Silverstein upped his offer to $ 3.22 billion. However, Vornado insisted on last minute changes to

8201-512: The collapse being the result of explosives; it found that a combination of factors including physical damage, fire, and the building's unusual construction set off a chain-reaction collapse. In May 2002, the Federal Emergency Management Agency (FEMA) issued a report on the collapse based on a preliminary investigation conducted jointly with the Structural Engineering Institute of the American Society of Civil Engineers under

8340-510: The completion of the Sears Tower in 1973. They were not surpassed until the construction of the Burj Khalifa , which opened in 2010. The towers were also the world's tallest twin towers until 1996, when the Petronas Towers opened. Each tower had a total mass of around 500,000 tons. The original World Trade Center had a five-acre (two-hectare) plaza around which all of the buildings in

8479-407: The complex in March 1966. Despite public criticism over the height of the 110-story twin towers, Yamasaki & Associates and Emery Roth & Sons made only relatively minor changes to the plans, which were released in May 1966. The revised plans called for the twin towers and four additional low-rise structures to surround the central plaza. Yamasaki's design for the World Trade Center called for

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8618-404: The complex, including the twin towers, were centered. World Trade Center officials had wanted the plaza to be a "contemplative space" or a Zen garden . In 1982, the plaza was renamed after Port Authority's late chairman, Austin J. Tobin, who authorized the construction of the original World Trade Center. During the summer, the Port Authority installed a portable stage, typically backed up against

8757-401: The complex. On September 20 , 1962, the Port Authority announced the selection of Minoru Yamasaki as lead architect and Emery Roth & Sons as associate architects. Yamasaki devised the plan to incorporate twin towers. His original plan called for the towers to be 80 stories tall, but to meet the Port Authority's requirement for 10,000,000 square feet (930,000 m ) of office space,

8896-433: The concrete lining in the undersea tunnel down to about 50 mm. In ordinary building fires, concrete typically achieves excellent fire-resistance ratings, unless it is too wet, which can cause it to crack and explode. For unprotected concrete, the sudden endothermic reaction of the hydrates and unbound humidity inside the concrete generates pressure high enough to spall off the concrete, which falls in small pieces on

9035-400: The concrete or masonry blocks is forced into the vault chamber as steam, which soaks the paper documents to keep them from igniting. This steam also helps keep the temperature inside the vault chamber below the critical 176.7 °C (350 °F) threshold, which is the point at which information on paper documents is destroyed. The paper can later be remediated with a freeze drying process if

9174-406: The conspiracy theories that 7 World Trade Center was brought down by controlled demolition. Specifically, the window breakage pattern and blast sounds that would have resulted from the use of explosives were not observed. The suggestion that an incendiary material such as thermite was used instead of explosives was considered unlikely by NIST because of the building's structural response to the fire,

9313-461: The construction of the World Trade Center took place on August 5 , 1966. The site of the World Trade Center was located on filled land with the bedrock located 65 feet (20 m) below. To construct the World Trade Center, it was necessary to build a " bathtub " with a slurry wall around the West Street side of the site, to keep water from the Hudson River out. The slurry method selected by

9452-513: The construction process, and the first tenants moved into the North Tower on December 15, 1970 , while it was still under construction, while the South Tower began accepting tenants in January 1972 . The complex had 111 tenants with a combined 1,800 employees by late 1971. When the Twin Towers were completed, the total costs to the Port Authority had reached $ 900 million. The ribbon-cutting ceremony took place on April 4 , 1973. In addition to

9591-412: The conventional materials, purpose-designed spray fireproofing plasters have become abundantly available the world over. The inorganic methods include: Gypsum plasters include chemical additives to create bubbles that displace solids, thus reducing the bulk density. Lightweight polystyrene beads may be mixed into the plasters at the factory in an effort to reduce the density, which generally results in

9730-462: The course. Windows on the World was forced to close following the 1993 World Trade Center bombing as the explosion damaged receiving areas, storage and parking spots used by the restaurant complex. On May 12, 1994, the Joseph Baum & Michael Whiteman Company won the contract to run the restaurants after Windows's former operator, Inhilco , gave up its lease. After its reopening on June 26, 1996,

9869-437: The critical strength limit is to use liquid convection cooling in hollow structural members. This method was patented in the 19th century although the first prominent example was 89 years later. Traffic tunnels may be traversed by vehicles carrying flammable goods, such as petrol, liquefied petroleum gas and other hydrocarbons , which are known to cause a very rapid temperature rise and high ultimate temperatures in case of

10008-443: The deal, including a shorter 39-year lease, which the Port Authority considered nonnegotiable. Vornado later withdrew and Silverstein's bid for the lease to the World Trade Center was accepted on April 26 , 2001, and closed on July 24 , 2001. On September 11, 2001 , Islamist terrorists hijacked two commercial airliners and crashed them into the Twin Towers. One group led by Mohamed Atta crashed American Airlines Flight 11 into

10147-501: The design to stack local elevators within the same elevator shaft. Located on the 44th and 78th floors of each tower, the sky lobbies enabled the elevators to be used efficiently. This increased the amount of usable space on each floor from 62 to 75 percent by reducing the number of elevator shafts. Altogether, the World Trade Center had 95 express and local elevators. The structural engineering firm Worthington, Skilling, Helle & Jackson worked to implement Yamasaki's design, developing

10286-414: The distribution of loads between the new and old caissons. Above the 7th floor, the building's structure was a typical tube-frame design, with columns in the core and on the perimeter, and lateral loads resisted by perimeter moment frames. A shipping and receiving ramp, which served the entire World Trade Center complex, occupied the eastern quarter of the 7 World Trade Center footprint. The building

10425-474: The effects of such fires upon traffic tunnels. Cementitious spray fireproofing must be certification-listed and applied in the field as per that listing , using a hydrocarbon fire test curve such as the one used in UL1709. Fireproof vaults to protect important paper documents are usually built using concrete or masonry blocks as the primary building material. In the event of a fire, the chemically-bound water within

10564-579: The effects of thermal expansion on floor support systems be considered. Recognizing that current building codes are drawn to prevent loss of life rather than building collapse, the main point of NIST's recommendations was that buildings should not collapse from fire even if sprinklers are unavailable. The collapse of 7 WTC sent debris flying into the nearby Borough of Manhattan Community College 's Fiterman Hall building, located at 30 West Broadway, damaging and contaminating it beyond repair. A revised plan called for demolition in 2009 and completion of

10703-447: The emergency command center and associated fuel tanks at 7 World Trade Center. Although this decision was criticized in light of the events of 9/11 , the fuel in the building is not believed to have contributed to the collapse of the building. At the time of the September 11 attacks, Salomon Smith Barney was by far the largest tenant in 7 World Trade Center, occupying 1,202,900 sq ft (111,750 m) (64 percent of

10842-415: The exterior with the crumbling of a rooftop penthouse structure at 5:20:33 pm. This initiated the progressive collapse of the entire building at 5:21:10 pm , according to FEMA , while the 2008 NIST study placed the final collapse time at 5:20:52 pm . The collapse made the old 7 World Trade Center the first steel skyscraper known to have collapsed primarily due to uncontrolled fires. A new building on

10981-465: The facade just before the entire building started to fall. According to FEMA, this collapse started at 5:20:33 pm EDT when the east mechanical penthouse started crumbling. Differing times are given as to what time the building completely collapsed: at 5:21:10 pm EDT according to FEMA, and at 5:20:52 pm EDT according to NIST. There were no casualties associated with the collapse. NIST found no evidence to support conspiracy theories such as

11120-523: The fire and was criminally charged. The first terrorist attack on the World Trade Center occurred on February 26, 1993, at 12:17 p.m. A Ryder truck filled with 1,500 pounds (680 kg) of explosives (planted by Ramzi Yousef ) detonated in the North Tower's underground garage. The blast opened a 100 ft (30 m) hole through five sublevels, with the greatest damage occurring on levels B1 and B2 and significant structural damage on level B3. Six people were killed and 1,042 others were injured in

11259-426: The fire is extinguished before internal temperatures exceed 176.7 °C (350 °F). An alternate less expensive and time-consuming construction method is using dry insulating material. This vault construction method is sufficient for paper documents, but the steam generated by concrete and masonry structures will destroy contents that are more sensitive to heat and moisture. For example, information on microfilm

11398-459: The floor of the tunnel. Humidity probes are inserted into all concrete slabs that undergo fire testing to test for this, even for the less severe building elements curve (DIN4102, ASTM E119, BS476, or ULC-S101). The need for fireproofing was demonstrated, among other fire protection measures, in the European "Eureka" Fire Tunnel Research Project, which gave rise to building codes for the trade to avoid

11537-497: The floors. The trusses connected to the perimeter at alternate columns and were on 6 foot 8 inch (2.03 m) centers. The top chords of the trusses were bolted to seats welded to the spandrels on the exterior side and a channel welded to the core columns on the interior side. The floors were connected to the perimeter spandrel plates with viscoelastic dampers that helped reduce the amount of sway felt by building occupants. Hat trusses (or "outrigger trusses") located from

11676-417: The global response to the initiating events. NIST determined that diesel fuel did not play an important role, nor did the structural damage from the collapse of the Twin Towers or the transfer elements (trusses, girders, and cantilever overhangs). The lack of water to fight the fire was an important factor. The fires burned out of control during the afternoon, causing floor beams near column 79 to expand and push

11815-457: The governors of both New York and New Jersey . New Jersey Governor Robert B. Meyner objected to New York getting a $ 335 million project. Toward the end of 1961, negotiations with outgoing New Jersey Governor Meyner reached a stalemate. At the time, ridership on New Jersey's H&M Railroad had declined substantially—from a high of 113 million riders in 1927, to 26 million in 1958—after new automobile tunnels and bridges had opened across

11954-418: The investigation of the collapse of the Twin Towers. In June 2007, Shyam Sunder explained, We are proceeding as quickly as possible while rigorously testing and evaluating a wide range of scenarios to reach the most definitive conclusion possible. The 7 WTC investigation is in some respects just as challenging, if not more so than the study of the towers. However, the current study does benefit greatly from

12093-401: The leadership of Dr. W. Gene Corley , P.E. FEMA made preliminary findings that the collapse was not primarily caused by actual impact damage from the collapse of 1 WTC and 2 WTC but by fires on multiple stories ignited by debris from the other two towers that continued burning unabated due to lack of water for sprinklers or manual firefighting. The report did not reach conclusions about

12232-619: The lease to Silverstein Properties in July 2001 . During its existence, the World Trade Center symbolized globalization and the economic prosperity of the U.S. Although its design was initially criticized by New Yorkers and architectural critics, the Twin Towers became an icon of New York City. It had a major role in popular culture , and according to one estimate was depicted in 472 films. The Twin Towers were also used in Philippe Petit 's tightrope-walking performance on August 7, 1974. Following

12371-442: The lobby of 7 World Trade Center housed a large mural by artist Al Held , titled The Third Circle . The groundbreaking ceremony was hosted on October 2, 1984. The building opened in May 1987 as part of the World Trade Center . In June 1986, before construction was completed, developer Larry Silverstein signed Drexel Burnham Lambert as a tenant to lease the entire 7 World Trade Center building for $ 3 billion over

12510-400: The main buildings of the World Trade Center. Construction of the North Tower at One World Trade Center began in 1966 with the South Tower at Two World Trade Center. When completed in 1972, 1 World Trade Center became the tallest building in the world for two years, surpassing the Empire State Building after its 40-year reign. The North Tower stood 1,368 feet (417 m) tall and featured

12649-429: The modular pieces off-site at the fabrication shop. Adjacent modules were bolted together with the splices occurring at mid-span of the columns and spandrels. The spandrel plates were located at each floor, transmitting shear stress between columns, allowing them to work together in resisting lateral loads. The joints between modules were staggered vertically so that the column splices between adjacent modules were not on

12788-461: The morning of August 7, 1974, Philippe Petit performed a high-wire walk between the North and South Towers of the World Trade Center. For his unauthorized feat 1,312 feet (400 m) above the ground, he rigged a 440-pound (200 kg) cable and used a custom-made 30-foot-long (9.1 m), 55-pound (25 kg) balancing pole. He performed for 45 minutes, making eight passes along the wire. Though Petit

12927-414: The nature of the fire, and the unlikelihood that a sufficient amount of thermite could be planted without discovery. Based on its investigation, NIST reiterated several recommendations it had made in its earlier report on the collapse of the Twin Towers. It urged immediate action on a further recommendation: that fire resistance should be evaluated under the assumption that sprinklers are unavailable; and that

13066-435: The nearby North Tower (1 World Trade Center) collapsed . The debris ignited fires on multiple lower floors of the building, which continued to burn uncontrolled throughout the afternoon. The building's internal fire suppression system lacked water pressure to fight the fires. It began to collapse when a critical internal column buckled and triggered cascading failure of nearby columns throughout, which were first visible from

13205-483: The new Fiterman Hall in 2012, at a cost of $ 325 million. The collapse also damaged the eastern facade of the Barclay–Vesey Building , an Art Deco building to the west; it was restored at a cost of US$ 1.4 billion. Construction on the new 7 World Trade Center began in 2002, and the new structure opened in 2006. World Trade Center (1973%E2%80%932001) The original World Trade Center ( WTC )

13344-494: The new location and the Port Authority's acquisition of the H&M Railroad, New Jersey agreed to support the World Trade Center project. As part of the deal, the Port Authority renamed the H&M "Port Authority Trans-Hudson", or PATH for short. To compensate Radio Row business owners for their displacement, the Port Authority gave each business $ 3,000 without regard to how long the business had been there or how prosperous it was. The Port Authority began purchasing properties in

13483-475: The north of the superblock. Beneath the World Trade Center complex was an underground shopping mall . It had connections to various mass transit facilities, including the New York City Subway system and the Port Authority's PATH trains. One of the world's largest gold depositories was located underneath the World Trade Center, owned by a group of commercial banks. The 1993 bombing detonated close to

13622-476: The northern facade of the North Tower at 8:46:40 a.m.; the aircraft struck between the 93rd and 99th floors. Seventeen minutes later, at 9:03:11 a.m., a second group led by Marwan al-Shehhi crashed the similarly hijacked United Airlines Flight 175 into the southern facade of the South Tower, striking it between the 77th and 85th floors. Fireproofing Applying a certification listed fireproofing system to certain structures allows them to have

13761-431: The plaza next to 4 World Trade Center called "Gemelli". The following year, he opened another restaurant in an adjacent place called "Pasta Break". On June 9, 1999, the outdoor plaza reopened after undergoing $ 12 million in renovations. This involved replacing marble pavers with over 40,000 gray and pink granite stones, as well as adding benches, planters, food kiosks, and outdoor dining areas. Although most of

13900-528: The plaza. 6 World Trade Center , at the northwest corner, housed the United States Customs Service . 5 World Trade Center was located at the northeast corner above the PATH station, and 4 World Trade Center , located at the southeast corner, housed the U.S. Commodities Exchange . In 1987, construction was completed on a 47-floor office building, 7 World Trade Center , located to

14039-695: The remaining portion of the building above to fall down as a single unit. The fires, which were fueled by office contents and burned for 7 hours, along with the lack of water, were the key reasons for the collapse. At the time, this made the old 7 WTC the only steel skyscraper to have collapsed from fire, but not the last, with others including Edifício Wilton Paes de Almeida , the Plasco Building , and Windsor Tower . Files relating to numerous federal investigations had been housed at 7 World Trade Center. The Equal Employment Opportunity Commission estimated over 10,000 of its cases were affected. Investigative files in

14178-485: The remaining space. By April 1988, he had lowered the rent and made other concessions. In November 1988, Salomon Brothers withdrew from plans to build a large new complex at Columbus Circle in Midtown , instead agreeing to a 20-year lease for the top 19 floors of 7 World Trade Center. The building was extensively renovated in 1989 to accommodate Salomon Brothers, and 7 World Trade Center alternatively became known as

14317-408: The restaurant two out of four stars, signifying a "very good" quality. In his 2009 book Appetite , William Grimes wrote that, "At Windows, New York was the main course". In 2014, Ryan Sutton of Eater.com compared the now-destroyed restaurant's cuisine to that of its replacement, One World Observatory . He said, "Windows helped usher in a new era of captive audience dining in that the restaurant

14456-400: The same floor. Below the 7th floor to the foundation, there were fewer, wider-spaced perimeter columns to accommodate doorways. The core of the towers housed the elevator and utility shafts, restrooms, three stairwells, and other support spaces. The core of each tower was a rectangular area 87 by 135 feet (27 by 41 m) and contained 47 steel columns running from the bedrock to the top of

14595-404: The second floor, visitors were required to pass through security checks added after the 1993 World Trade Center bombing . They were then sent to the 107th-floor indoor observatory at a height of 1,310 feet (400 m) by a dedicated express elevator, which could be only accessed by entering the core. The exterior columns were narrowed to allow 28 inches of window width between them. In 1995,

14734-400: The second tallest building in the world at 1,362 feet (415 m). Its rooftop observation deck was 1,362 ft (415 m) high and its indoor observation deck was 1,310 ft (400 m) high. Each tower stood over 1,350 feet (410 m) high, and occupied about 1 acre (4,000 m ) of the total 16 acres (65,000 m ) of the site's land. During a press conference in 1973, Yamasaki

14873-576: The significant technological advances achieved and lessons learned from our work on the towers. In November 2008, NIST released its final report on the causes of the collapse of 7 World Trade Center. This followed NIST's August 21, 2008, draft report, which included a period for public comments, and was followed in 2012 by a peer-reviewed summary in the Journal of Structural Engineering . In its investigation, NIST utilized ANSYS to model events leading up to collapse initiation and LS-DYNA models to simulate

15012-403: The site opened in 2006. The original 7 World Trade Center was a 47-story building, designed by Emery Roth & Sons , with a red granite facade. The building was 610 feet (190 m) tall, with a trapezoidal footprint that was 330 ft (100 m) long and 140 ft (43 m) wide. Tishman Realty & Construction managed construction of the building. 7 World Trade Center

15151-432: The situation", said a district manager of Silverstein Properties . According to Larry Silverstein, the unusual task was possible because it could allow "entire portions of floors to be removed without affecting the building's structural integrity, on the assumption that someone might need double-height floors." After the World Trade Center bombing of February 26, 1993, New York City mayor Rudy Giuliani decided to situate

15290-463: The south face of the building and starting fires that continued to burn throughout the afternoon. The collapse also caused damage to the southwest corner between floors 7 and 17 and on the south face between floor 44 and the roof; other possible structural damage included a large vertical gash near the center of the south face between floors 24 and 41. The building was equipped with a sprinkler system , but had many single-point vulnerabilities for failure:

15429-500: The space in the World Trade Center complex was off-limits to the public, the South Tower featured a public glass-enclosed observation deck on the 107th floor called Top of the World and an open-air deck with the height of 110 stories. The observation deck opened in December 1975 and operated from 9:30 a.m. to 11:30 p.m. (June to August) and from 9:30 a.m. – 9:30 p.m. (September to May). After paying an entrance fee in

15568-460: The sprinkler system required manual initiation of the electrical fire pumps instead of being a fully automatic system; the floor-level controls had a single connection to the sprinkler water riser, and the sprinkler system required some power for the fire pump to deliver water. Additionally, water pressure was low, with little or no water to feed sprinklers. After the North Tower collapsed, some firefighters entered 7 World Trade Center to search

15707-441: The surface of the debris near 7 World Trade Center and evacuate the area due to concerns for the safety of personnel. The fire expanded the girders of the building, causing some to collapse. This led to the northeast corner core column (Column 79), which was especially large, to buckle below the 13th floor. This caused the floors above it to collapse to the transfer floor at the fifth level. The structure also developed cracks in

15846-524: The sways. These viscoelastic dampers, used throughout the structures at the joints between floor trusses and perimeter columns along with some other structural modifications, reduced the building sway to an acceptable level. In March 1965, the Port Authority began acquiring property at the World Trade Center site. Demolition work began on March 21 , 1966, to clear thirteen square blocks of low rise buildings in Radio Row for its construction. Groundbreaking for

15985-434: The taller the building, the more elevators are needed to service it, requiring more space-consuming elevator banks. Yamasaki and the engineers decided to use a new system with two " sky lobbies "—floors where people could switch from a large-capacity express elevator to a local elevator that goes to each floor in a section. This system, inspired by the local-express train operation used in New York City's subway system, allowed

16124-438: The tower. In addition to fire damage on the 9th through the 14th floors, the water used to extinguish the fire damaged a few of the floors below. At that time, the World Trade Center had no fire sprinkler systems . On March 12, 1981, the Port Authority announced a $ 45 million plan to install sprinklers throughout the World Trade Center. A disgruntled custodian, 19 year old Oswald Adorno, was discovered to have deliberately started

16263-454: The tower. The large, column-free space between the perimeter and core was bridged by prefabricated floor trusses. The floors supported their own weight as well as live loads , providing lateral stability to the exterior walls and distributing wind loads among the exterior walls. The floors consisted of 4-inch (10 cm) thick lightweight concrete slabs laid on a fluted steel deck. A grid of lightweight bridging trusses and main trusses supported

16402-463: The towers, as well as all 157 on board the two aircraft. Falling debris from the towers, combined with fires in several surrounding buildings that were initiated by falling debris, led to the partial or complete collapse of all the WTC complex's buildings, including 7 World Trade Center , and caused catastrophic damage to 10 other large structures in the surrounding area. The cleanup and recovery process at

16541-540: The transmission tower. The framed-tube design, using steel core and perimeter columns protected with sprayed-on fire-resistant material, created a relatively lightweight structure that would sway more in response to the wind compared to traditional structures, such as the Empire State Building that has thick, heavy masonry for fireproofing of steel structural elements. During the design process, wind tunnel tests were done to establish design wind pressures that

16680-454: The vault. Seven weeks after the September 11 attacks, $ 230 million in precious metals was removed from basement vaults of 4 WTC. This included 3,800 100-Troy-ounce 24 carat gold bars and 30,000 1,000-ounce silver bars. On February 13, 1975, a three-alarm fire broke out on the North Tower's 11th floor. It spread to the 9th and 14th floors after igniting telephone cable insulation in

16819-577: The world's first world trade center . They had two choices: the east side of Lower Manhattan , near the South Street Seaport ; or the west side, near the Hudson and Manhattan Railroad (H&M) station, Hudson Terminal . Initial plans, made public in 1961, identified a site along the East River for the World Trade Center. As a bi-state agency, the Port Authority required approval for new projects from

16958-511: Was a warehouse district in what is now Tribeca and the Financial District . Harry Schneck opened City Radio on Cortlandt Street in 1921, and eventually, the area held several blocks of electronics stores, with Cortlandt Street as its central axis. The used radios, war surplus electronics (e.g., AN/ARC-5 radios), junk, and parts were often piled so high they would spill out onto the street, attracting collectors and scroungers. According to

17097-452: Was a 180-seat cafeteria on the 44th floor of 1 WTC conceived for office workers, was also operated by Windows on the World. In its last iteration, Windows on the World received mixed reviews. Ruth Reichl , a New York Times food critic, said in December 1996 that "nobody will ever go to Windows on the World just to eat, but even the fussiest food person can now be content dining at one of New York's favorite tourist destinations". She gave

17236-640: Was a complex of seven buildings in the Financial District of Lower Manhattan in New York City . Built primarily between 1966 and 1975, it was dedicated on April 4, 1973, and was destroyed during the September 11 attacks in 2001. At the time of their completion, the 110-story-tall Twin Towers , including the original 1 World Trade Center (the North Tower) at 1,368 feet (417 m), and 2 World Trade Center (the South Tower) at 1,362 feet (415.1 m), were

17375-527: Was a destination in itself, rather than a lazy by-product of the vital institution it resided in." Five smaller buildings stood on the 16-acre (65,000 m ) block. One was the 22-floor hotel, which opened at the southwest corner of the site in 1981 as the Vista Hotel ; in 1995, it became the Marriott World Trade Center (3 WTC). Three low-rise buildings (4 WTC, 5 WTC, and 6 WTC), which were steel-framed office buildings, also stood around

17514-438: Was asked, "Why two 110-story buildings? Why not one 220-story building?" His tongue-in-cheek response was: "I didn't want to lose the human scale." Architectural critic Ada Louise Huxtable criticized the design of the twin towers when they were first announced, saying: "Here we have the world's daintiest architecture for the world's biggest buildings." The twin towers had more floors (at 110) than any other building before

17653-400: Was built. The structural design of 7 World Trade Center therefore included a system of gravity column transfer trusses and girders, located between floors 5 and 7, to transfer loads to the smaller foundation. Existing caissons installed in 1967 were used, along with new ones, to accommodate the building. The 5th floor functioned as a structural diaphragm, providing lateral stability and

17792-544: Was charged with criminal trespass and disorderly conduct, he was later freed in exchange for performing for children in Central Park . On February 20, 1981, an Aerolíneas Argentinas airliner was guided away by air traffic controllers after radar signals indicated it was on a collision course with the North Tower (1 WTC). The aircraft, which departed from José Joaquín de Olmedo International Airport in Guayaquil , Ecuador, and

17931-578: Was concentrated in Midtown Manhattan . To help stimulate urban renewal in Lower Manhattan, David Rockefeller suggested that the Port Authority build a World Trade Center there. Plans for the use of eminent domain to remove the shops in Radio Row bounded by Vesey , Church , Liberty , and West Streets began in 1961 when the Port Authority of New York and New Jersey was deciding to build

18070-399: Was constructed above a two-story Con Edison substation that had been located on the site since 1967. The substation had a caisson foundation designed to carry the weight of a future building of 25 stories containing 600,000 sq ft (56,000 m). However, the final design for 7 World Trade Center was for a much larger building than originally planned when the substation

18209-503: Was delayed until after reports were completed on the Twin Towers. In the meantime, NIST provided a preliminary report about 7 WTC in June 2004, and thereafter released occasional updates on the investigation. According to NIST, the investigation of 7 World Trade Center was delayed for a number of reasons, including that NIST staff who had been working on 7 World Trade Center were assigned full-time from June 2004 to September 2005 to work on

18348-407: Was developed by Larry Silverstein , who held a ground lease for the site from the Port Authority of New York and New Jersey , and designed by Emery Roth & Sons . It was destroyed during the September 11 attacks . The original 7 World Trade Center was 47 stories tall, clad in red granite masonry, and occupied a trapezoidal footprint. An elevated walkway spanning Vesey Street connected

18487-515: Was developed by restaurateur Joe Baum at a cost of more than $ 17 million. As well as the main restaurant, two offshoots were located at the top of the North Tower: Hors d'Oeuvrerie (offered a Danish smorgasbord during the day and sushi in the evening) and Cellar in the Sky (a small wine bar ). Windows on the World also had a wine school program run by Kevin Zraly , who published a book on

18626-407: Was heavily damaged. After the bombing, the Port Authority installed photoluminescent pathway markings in the stairwells. The fire alarm system for the entire complex needed to be replaced because critical wiring and signaling in the original system were destroyed. A memorial to the victims of the bombing, a reflecting pool , was installed with the names of those who were killed in the blast. It

18765-484: Was later destroyed following the September 11 attacks. The names of the victims of the 1993 bombing are included in the National September 11 Memorial & Museum . In January 1998, a DeCavalcante crime family member Ralph Guarino gained maintenance access to the World Trade Center. He arranged a three-man crew for a heist that netted over $ 2 million from a Brinks delivery to the North Tower's 11th floor. On

18904-519: Was necessary before the excavation of material from the interior of the site could begin. The 1,200,000 cubic yards (920,000 m ) of excavated material were used (along with other fill and dredge material) to expand the Manhattan shoreline across West Street to form Battery Park City . The Port Authority awarded $ 74 million in contracts to various steel suppliers in January 1967, and excavation of

19043-447: Was open below the 3rd floor, providing space for truck clearance on the shipping ramp. The spray-on fireproofing for structural steel elements was gypsum -based Monokote , which had a two-hour fire rating for steel beams, girders, and trusses, and a three-hour rating for columns. Mechanical equipment was installed on floors four through seven, including 12  transformers on the 5th floor. Several emergency generators installed in

19182-508: Was scheduled to land at nearby JFK Airport , was flying at a much lower altitude than regulations recommended. The 1995 PCA world chess championship was played on the 107th floor of the South Tower. On February 8, 2000, a worker was crushed to death and another was injured by an industrial cooling unit. Slow leasing was a hallmark of the old World Trade Center complex. The Twin Towers suffered high vacancy rates for decades. The complex achieved 95% occupancy only in mid-2001. Following

19321-400: Was suggested by David Rockefeller to help stimulate urban renewal in Lower Manhattan, and his brother Nelson , then New York's 49th governor, signed the legislation to build it. The buildings at the complex were designed by Minoru Yamasaki . In 1998, the Port Authority of New York and New Jersey decided to privatize it by leasing the buildings to a private company to manage. It awarded

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