After 12:00 p.m. September 11, 2001: Oxygen Level Is Found to Be Dangerously Low in the Pentagon Command Center

Officers in the National Military Command Center (NMCC) at the Pentagon are concerned about the air quality in the center and an air quality expert subsequently informs them that the oxygen level there is dangerously low. [George C. Marshall European Center for Security Studies, 8/3/2012; Graff, 2019, pp. 277-278] From around 11:00 a.m., a small number of Pentagon officials, including Secretary of Defense Donald Rumsfeld and General Richard Myers, vice chairman of the Joint Chiefs of Staff, have been in the Joint Chiefs of Staff conference room within the NMCC, participating in a secure video teleconference with other government agencies (see (11:00 a.m.) September 11, 2001). [Historical Office, Office of the Secretary of Defense, 4/9/2003 ; Myers and McConnell, 2009, pp. 155]
Officials Start Feeling Unwell – During this teleconference, Colonel Matthew Klimow, Myers’s executive assistant, starts feeling sick and becomes unable to concentrate. [George C. Marshall European Center for Security Studies, 8/3/2012; Graff, 2019, pp. 277] Others in the room also feel unwell. “Our eyes became red and our throats itchy,” Rumsfeld will later recall. [Rumsfeld, 2011, pp. 340] Meanwhile, Vice Admiral Edmund Giambastiani Jr., Rumsfeld’s senior military assistant, is concerned about the conditions in the small conference room. “It started to get really hot and the air got bad,” he will describe. [Historical Office, Office of the Secretary of Defense, 8/1/2002 ; Graff, 2019, pp. 277-278] Realizing what the problem is, he shakes Klimow and then tells him what is wrong. “I’m a submariner; I know what’s going on,” he says and then explains: “There’s no oxygen in this room. It’s filling up with carbon dioxide.”
Officers Consider Moving to Another Area – “Let’s get everybody out of here,” he says. He suggests they all go to the Navy Command Center. Although Klimow is unaware that the Navy Command Center was destroyed when the Pentagon was hit (see 9:37 a.m. September 11, 2001 and 9:37 a.m. September 11, 2001), he rejects the proposal. “I’ve been trying to get hold of the [Navy Command Center]; I can’t raise him,” he says. He suggests they go to the Army Operations Center in the Pentagon basement instead. Giambastiani says he will do a reconnaissance to the Army Operations Center, and advises Klimow to “go find an air monitor and see how bad it is in here.” Klimow therefore calls Captain Chris Donahue, Myers’s military aide, and instructs him to find an air monitor.
Air Quality Expert Warns of Low Oxygen – Giambastiani subsequently returns from his reconnaissance, shaking his head. He tells Klimow they will be unable to go to the Army Operations Center since the passageways in the outer areas of the Pentagon are impassible due to thick smoke. Donahue then comes in with the Arlington County Fire Department’s air quality specialist. The air quality specialist has taken readings and explains to Klimow that he and the others in the conference room are in a precarious situation. “In some of the corridors in the Pentagon, the air is filled with about 88 percent carbon dioxide—that’s lethal,” he says. “In the outer office here in the NMCC you’re at 33 percent oxygen,” he continues. He says that in the conference room, “you’re at 16 percent oxygen.” If the oxygen level gets down to 13 percent, he says, “you cannot survive.” Therefore, he concludes, “You need to leave.” [George C. Marshall European Center for Security Studies, 8/3/2012; Graff, 2019, pp. 278] Fortunately, Giambastiani subsequently finds a smoke-free area for the group in the conference room to relocate to: the Executive Support Center (ESC) on the third floor of the Pentagon. Rumsfeld, Myers, and their entourage will therefore move to the ESC (see 12:19 p.m. September 11, 2001). [Historical Office, Office of the Secretary of Defense, 8/1/2002 ; Myers and McConnell, 2009, pp. 156-157]
Air Handling Units Have Been Shut Down – The lack of oxygen in the NMCC is apparently the result of a misunderstanding. According to Klimow, the “incident commander”—presumably meaning Assistant Chief James Schwartz of the Arlington County Fire Department—was incorrectly told that the entire Pentagon had been evacuated and, “with the fires raging out of control,” shut down the building’s air handling units. [George C. Marshall European Center for Security Studies, 8/3/2012] Rumsfeld, though, will suggest a different explanation. “The air-conditioning [in the Pentagon] was supposed to have been disabled to avoid circulating the hazardous smoke, but apparently it took some time for it to be shut down,” he will write. [Rumsfeld, 2011, pp. 340]