Narrative:

While at FL350 cruise; flight attendants notified flight deck of a suspicious acrid/burning sulphuric type fumes/odor in cabin emanating from row 10 to aft of the aircraft. Passengers were also aware of odor and were voicing complaints and concerns to cabin crew. We responded to cabin crew to keep us informed if it got worse. We first attempted to mitigate/dissipate smell by switching to hi on packs selector with no noticeable results. We then attempted to isolate the source by alternately operating left and right air conditioning packs with no results. Smell continued to get worse according to cabin/passengers (although we had no detection or smell in cockpit). We then elected to accomplish fumes/smoke QRH. Since passengers were complaining and concerned (as well as flight attendants) we elected to divert to a nearby airport.we did not declare emergency to ATC; however; we requested priority handling with a description of cabin fumes/odor issue. We accomplished the 'test' issues with cabin crew and accomplished a normal (but over weight) landing and proceeded to assigned gate. Station personnel were waiting for us. I had the passengers remain on board until conferring with dispatch and maintenance control; then arranged with station personnel to allow passengers into gate area for possible rebooking. I also arranged for medical personnel to be at gate and notified passengers that if anyone was feeling ill that they should inform emt personnel. All 3 flight attendants were feeling ill and after conferring with the emt personnel; elected to go to hospital to be checked out; as well as some of the passengers. Cabin crew was admitted and subsequently discharged. I arranged to have them ron. Captain and first officer suffered no ill effects except for a continuous low-grade head ache for me (captain) that has lasted through the next day. All information documented in the maintenance log as well as cabin air safety report was faxed to maintenance control. There is indeed something that cause the fumes/odor; as they somewhat dissipated when thrust levers/power retarded for descent. I suspect either a seal/o-ring in engines or air cycle machines. At no time was smell/odor detectable on flight deck.

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Original NASA ASRS Text

Title: An A320 diverted because a sulfuric type odor in the cabin made flight attendants and passengers ill. Some required medical attention.

Narrative: While at FL350 cruise; flight attendants notified flight deck of a suspicious acrid/burning sulphuric type fumes/odor in cabin emanating from row 10 to aft of the aircraft. Passengers were also aware of odor and were voicing complaints and concerns to cabin crew. We responded to cabin crew to keep us informed if it got worse. We first attempted to mitigate/dissipate smell by switching to hi on packs selector with no noticeable results. We then attempted to isolate the source by alternately operating left and right air conditioning packs with no results. Smell continued to get worse according to cabin/passengers (although we had no detection or smell in cockpit). We then elected to accomplish fumes/smoke QRH. Since passengers were complaining and concerned (as well as flight attendants) we elected to divert to a nearby airport.We did not declare emergency to ATC; however; we requested priority handling with a description of cabin fumes/odor issue. We accomplished the 'test' issues with cabin crew and accomplished a normal (but over weight) landing and proceeded to assigned gate. Station personnel were waiting for us. I had the passengers remain on board until conferring with dispatch and maintenance control; then arranged with station personnel to allow passengers into gate area for possible rebooking. I also arranged for medical personnel to be at gate and notified passengers that if anyone was feeling ill that they should inform EMT personnel. All 3 flight attendants were feeling ill and after conferring with the EMT personnel; elected to go to hospital to be checked out; as well as some of the passengers. Cabin crew was admitted and subsequently discharged. I arranged to have them RON. Captain and First Officer suffered no ill effects except for a continuous low-grade head ache for me (Captain) that has lasted through the next day. All information documented in the maintenance log as well as cabin air safety report was faxed to Maintenance Control. There is indeed something that cause the fumes/odor; as they somewhat dissipated when thrust levers/power retarded for descent. I suspect either a seal/o-ring in engines or air cycle machines. At no time was smell/odor detectable on flight deck.

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.