Date: 201304
Local time of day: 1801-2400
Location: ZZZ.Airport, US
Flight conditions: VMC
Light: Dusk
Aircraft: A319
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Parked; Taxi
ATC / advisory: Ground ZZZ; Ramp ZZZ
Aircraft component: Air Conditioning Distribution System
Component problem: Malfunctioning; Design
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Time Pressure; Physiological - Other; Distraction; Communication Breakdown
Second reporter function: Flight Attendant (On Duty)
Anomaly: Aircraft Equipment Problem Less Severe; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Detector: Person Flight Attendant; Person Flight Crew
When detected: Pre-flight; Taxi
Result: Flight Crew Returned To Gate; Flight Crew Took Evasive Action; General Physical Injury / Incapacitation; General Flight Cancelled / Delayed; General Maintenance Action
Contributing factors: Company Policy; Human Factors; Aircraft
Primary problem: Aircraft

Narrative: [We] had an unidentified odor of an acrid chemical nature that circulated throughout the cabin when the flight was boarding. At this point; the odor was not extremely intense; and the flight attendants; in retrospect; probably misidentified the odor as the body odor of a man sitting in First Class; which they described to me as the absolute worst they have ever smelled in their lives. This was a passenger on the inbound flight; and the flight attendants presumed the odor was still lingering. I wasn't so sure that could be so; but deferred to their judgment and anticipated that it would surely eventually dissipate; especially after running the air conditioning packs for a while; away from the gate; and on engine bleed. After only a brief period of taxi; however; the odor did not dissipate; but became stronger; and I got a call from the flight attendants; who were alarmed at the increased intensity of the odor; and complained of symptoms; including headaches; throat irritation and light headedness. The First Officer also indicated to me symptoms of throat irritation. I returned to the gate; and had the passengers and crew deplaned. I stayed on the aircraft only long enough to take care of duties relating to securing the aircraft; contacting station operations; retrieving paperwork; etc. I was last off the airplane; and did some remaining paperwork on the jetway. I myself had slight throat irritation and mild headache symptoms. All crew members went to the hospital for tests. The company needs to develop a checklist for crew members; detailing how to deal with this kind of event. A plan needs to be in place to take care of the crew members; and station personnel need to be able to implement it immediately. We were delayed in getting to the hospital by; I can't remember; but it was more than an hour and maybe less than 2 hours; because no company person (Chief Pilot; Dispatcher; Systems Crew Scheduling; Station Manager; etc.) could tell us promptly and decisively what to do. Fortunately (in a way) the First Officer had known someone who had a serious exposure over a year ago; and was able to contact this person to get some guidance. The remaining guidance came from sources at the Union. By the time we all left the hospital (we were all oxygenated for two to three hours); we felt improvement and very limited intensities of the symptoms we originally reported. We all hope that this exposure had only limited effects; that is; limited to the symptoms that occurred during and immediately after the exposure. However; because of the unknowns; many of us have some anxiety. I know of one of the flight attendants; who; having felt better upon leaving the hospital; later that night suffered a severe headache and nausea; that persisted for a couple of hours. Without knowing what the source of the odor/fumes was; I don't have a suggestion for future prevention. But I would definitely like to be contacted when Maintenance has determined a source/cause of this event.


Second narrative: I was working the 'C' position during boarding. During the boarding process; the APU was running and the air conditioning system was on and emitting a strange odor; it smelled kind of like stinky socks. Within the first five minutes of smelling the odor I got a headache and irritation in my throat. I asked the 'A' Flight Attendant if she could smell the odor; and she said yes. She also mentioned she was getting a headache. We finished the boarding process and taxied out with the odor continuing the whole time. I then called the 'B' Flight Attendant and asked if she was detecting the same smell. She said she was and that she had gotten a headache. I then called the Captain to tell him we had a persistent odor in the cabin and the cabin crew all had headaches. He said the cockpit crew also smelled the odor and that we would be returning to the gate to have Maintenance evaluate the situation.I think it advisable to make the investigation and solution of each airplane's air quality system a top priority in order to insure the safety of the passengers and crew.


Synopsis: An A319 Flight Attendant detected a dirty socks odor at the gate with the APU running and during taxi all three flight attendants reported headaches so after notifying the Captain; who also detected it; the aircraft returned to the gate. The crew sought medical attention.