Narrative:

We pushed off the gate and started the engines. I noticed that the right pack light was on. We completed the QRH checklist. The pack light did not go out so we returned to the gate. A flight attendant called the cockpit to report that she heard a series of 4 beeps or alarms; possibly coming from the floor beneath the aft galley floor; as we taxied into the gate. Maintenance personnel reported that there were no vehicles in the vicinity of the gate as we taxied in and that there was nothing abnormal in the cargo compartment. No source of the sounds was found. Maintenance performed tests on the right pack and the engine at the gate. No problems were found. I got a new flight plan for FL240 as a precaution against a pack failure or loss of pressurization in flight.we experienced normal engine start; taxi; takeoff and climb. All systems were functioning normally so I chose to climb to FL280. Approximately 15 minutes after level off; flight attendant 1 called the cockpit to report that a flight attendant was feeling faint and was on oxygen. I told her to page for a physician and to call me back with an update. I checked the cabin altitude and the differential pressure. Both were normal; the cabin altitude was approximately 4;800 ft. I set the cruise altitude to FL240 and observed the cabin altitude decreasing. I requested a descent to FL240. A few minutes later; flight attendant 1 called back and that a passenger had become ill. Before completing her report on the ill passenger; she stated that another flight attendant was talking incoherently. I asked her if she had found a physician. I asked her to get me the passenger's seat number and to give an update on their condition. Flight attendant 1 did not reply to my question about a physician and hung up; apparently to attend to the other flight attendant.the first officer and I began to prepare to divert. I observed the cabin altitude decreasing and the differential pressure increasing. I then attempted to contact dispatch via the radio to coordinate a diversion. I was unable to contact dispatch. I informed ATC that we were going to divert. Flight attendant 1 called again to report that another passenger was feeling faint with tingling in her fingers. She also reported that all of the oxygen bottles were being used and they needed to have the passenger oxygen system deployed. At this point; flight attendant 1 sounded hurried and alarmed so I deployed the masks. Deploying the oxygen masks would ensure that everyone had oxygen and that the flight attendants could then use the walk around bottles; if needed. We declared an emergency with ATC. We asked for further descent and a clearance to our divert airport. I made a PA informing the passengers that we were going to divert and would be landing in approximately 10 minutes. First officer and I discussed donning our oxygen masks. We were descending thru approximately FL150 and the cabin altitude was approximately 2;000 ft and decreasing normally. There were no fumes or odors. There was no sign of smoke. The flight attendants did not report any fumes; odors or signs of smoke. I told first officer that I felt fine and asked him how he felt. He replied that he was fine. Due to the fact that we were already in descent and would be below 10;000 ft very quickly; I felt that there would be no benefit to our use of the oxygen masks. Further; we had both been through military high altitude chamber training and are familiar with the effects of high altitude. We were not experiencing any symptoms and the cabin altitude was normal. I did not believe that there was an issue with the air quality in the cockpit or the cabin. From the information I was given by the flight attendants; the symptoms were limited to a couple of passengers and 2 flight attendants. Although unusual; I felt that the problems were caused by cabin altitude and not cabin air quality. We landed without incident and taxied to the gate. Paramedics met the aircraft. Ientered the cabin to assess the situation and coordinate with the paramedics. All passengers and flight attendants were alert and appeared normal. The paramedics entered the aircraft to assess the passengers' condition. The paramedics did not treat anyone. After approximately 10 minutes; the passengers deplaned. All passengers and crew appeared normal and walked off the aircraft under their own power. Several passengers complimented the flight attendants on their performance. Four passengers and one flight attendant went to the hospital. I was told that the passengers and the flight attendant were asthmatic. Two passengers returned and went on the flight to ord. Only a few passengers reported symptoms. A non-revenue air carrier pilot reported that he had no symptoms although he was sitting behind an ill passenger. I have been informed that someone may think that I should have performed a smoke; fire or fumes; smoke or fumes removal; or other checklist during this event. I am submitting this report in response to a possible violation of procedure. There was no report of smoke; or fumes in the cabin. No odors were reported. The first officer and I did not detect smoke; fumes or odors. The first officer and I had discussed the fact that we had both been through military high altitude chamber training. I also discussed a loss of pressurization event I had in while flying an F-4. I am very familiar with the symptoms of hypoxia. The fact that only a few of the passengers were affected led me to conclude that whatever caused the symptoms was not airborne but was related to the cabin altitude and the overall health of those individual passengers and flight attendants. I am told that each affected passenger or crewmember is asthmatic. I also felt is was possible that the flight attendants and some passengers had not eaten that morning due to the early departure and that may have contributed to their symptoms. Deploying the passenger masks appeared to be the best solution to the problem. A rapid or emergency descent would not alleviate the symptoms as quickly as deploying the oxygen masks and were already at a relatively low cabin altitude. Completing the smoke removal or other checklist would have delayed the landing. My intent was to land as soon as possible and get medical attention for the ill passengers and crew. Having no known cause for the problem; I felt that was the best course of action.

Related reports:

Google
 

Original NASA ASRS Text

Title: A B737-800 diverted due to undiagnosed respiratory problems experienced by passengers and flight attendants.

Narrative: We pushed off the gate and started the engines. I noticed that the right pack light was on. We completed the QRH checklist. The pack light did not go out so we returned to the gate. A flight attendant called the cockpit to report that she heard a series of 4 beeps or alarms; possibly coming from the floor beneath the aft galley floor; as we taxied into the gate. Maintenance personnel reported that there were no vehicles in the vicinity of the gate as we taxied in and that there was nothing abnormal in the cargo compartment. No source of the sounds was found. Maintenance performed tests on the right pack and the engine at the gate. No problems were found. I got a new flight plan for FL240 as a precaution against a pack failure or loss of pressurization in flight.We experienced normal engine start; taxi; takeoff and climb. All systems were functioning normally so I chose to climb to FL280. Approximately 15 minutes after level off; Flight Attendant 1 called the cockpit to report that a flight attendant was feeling faint and was on oxygen. I told her to page for a physician and to call me back with an update. I checked the cabin altitude and the differential pressure. Both were normal; the cabin altitude was approximately 4;800 FT. I set the cruise altitude to FL240 and observed the cabin altitude decreasing. I requested a descent to FL240. A few minutes later; Flight Attendant 1 called back and that a passenger had become ill. Before completing her report on the ill passenger; she stated that another flight attendant was talking incoherently. I asked her if she had found a physician. I asked her to get me the passenger's seat number and to give an update on their condition. Flight Attendant 1 did not reply to my question about a physician and hung up; apparently to attend to the other flight attendant.The First Officer and I began to prepare to divert. I observed the cabin altitude decreasing and the differential pressure increasing. I then attempted to contact Dispatch via the radio to coordinate a diversion. I was unable to contact Dispatch. I informed ATC that we were going to divert. Flight Attendant 1 called again to report that another passenger was feeling faint with tingling in her fingers. She also reported that all of the oxygen bottles were being used and they needed to have the passenger oxygen system deployed. At this point; Flight Attendant 1 sounded hurried and alarmed so I deployed the masks. Deploying the oxygen masks would ensure that everyone had oxygen and that the flight attendants could then use the walk around bottles; if needed. We declared an emergency with ATC. We asked for further descent and a clearance to our divert airport. I made a PA informing the passengers that we were going to divert and would be landing in approximately 10 minutes. First Officer and I discussed donning our oxygen masks. We were descending thru approximately FL150 and the cabin altitude was approximately 2;000 FT and decreasing normally. There were no fumes or odors. There was no sign of smoke. The flight attendants did not report any fumes; odors or signs of smoke. I told First Officer that I felt fine and asked him how he felt. He replied that he was fine. Due to the fact that we were already in descent and would be below 10;000 FT very quickly; I felt that there would be no benefit to our use of the oxygen masks. Further; we had both been through military high altitude chamber training and are familiar with the effects of high altitude. We were not experiencing any symptoms and the cabin altitude was normal. I did not believe that there was an issue with the air quality in the cockpit or the cabin. From the information I was given by the flight attendants; the symptoms were limited to a couple of passengers and 2 flight attendants. Although unusual; I felt that the problems were caused by cabin altitude and not cabin air quality. We landed without incident and taxied to the gate. Paramedics met the aircraft. Ientered the cabin to assess the situation and coordinate with the paramedics. All passengers and flight attendants were alert and appeared normal. The paramedics entered the aircraft to assess the passengers' condition. The paramedics did not treat anyone. After approximately 10 minutes; the passengers deplaned. All passengers and crew appeared normal and walked off the aircraft under their own power. Several passengers complimented the flight attendants on their performance. Four passengers and one flight attendant went to the hospital. I was told that the passengers and the flight attendant were asthmatic. Two passengers returned and went on the flight to ORD. Only a few passengers reported symptoms. A non-revenue air carrier pilot reported that he had no symptoms although he was sitting behind an ill passenger. I have been informed that someone may think that I should have performed a Smoke; Fire or Fumes; Smoke or Fumes Removal; or other checklist during this event. I am submitting this report in response to a possible violation of procedure. There was no report of smoke; or fumes in the cabin. No odors were reported. The First Officer and I did not detect smoke; fumes or odors. The First Officer and I had discussed the fact that we had both been through military high altitude chamber training. I also discussed a loss of pressurization event I had in while flying an F-4. I am very familiar with the symptoms of hypoxia. The fact that only a few of the passengers were affected led me to conclude that whatever caused the symptoms was not airborne but was related to the cabin altitude and the overall health of those individual passengers and flight attendants. I am told that each affected passenger or crewmember is asthmatic. I also felt is was possible that the flight attendants and some passengers had not eaten that morning due to the early departure and that may have contributed to their symptoms. Deploying the passenger masks appeared to be the best solution to the problem. A rapid or emergency descent would not alleviate the symptoms as quickly as deploying the oxygen masks and were already at a relatively low cabin altitude. Completing the smoke removal or other checklist would have delayed the landing. My intent was to land as soon as possible and get medical attention for the ill passengers and crew. Having no known cause for the problem; I felt that was the best course of action.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.