Narrative:

We pushed back; started both engines. We were approximately number 5; first flight of the day; shut down APU after engine start; taxied to spot 2. We got a call from 'a' flight attendant reporting fumes/odor (dirty socks) in the cabin. With parking brake set; called dispatch/maintenance. Maintenance advised to go back to the gate. Asked ground to return to gate; was approximately number 4 for takeoff; turned south on taxiway Y. Got another call from the 'a' flight attendant expressing increase odor and fumes; asked ground to expedite return to gate; they did. We returned to the gate; customers deplaned; no injuries during deplaning; customers left all belongings on aircraft; medics met the aircraft; took crew's vitals; went to the hospital for further evaluation; tested for tcp's and carbon monoxide. Possible pyrolization of aircraft oil or hydraulic fluid.

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Original NASA ASRS Text

Title: After start and beginning to taxi; the Captain shut down the APU. Shortly thereafter; the 'A' Flight Attendant notified the Captain of a dirty socks odor throughout the cabin so the aircraft was returned to the gate and deplaned. The crew was evaluated at an emergency room.

Narrative: We pushed back; started both engines. We were approximately Number 5; first flight of the day; shut down APU after engine start; taxied to Spot 2. We got a call from 'A' Flight Attendant reporting fumes/odor (dirty socks) in the cabin. With parking brake set; called Dispatch/Maintenance. Maintenance advised to go back to the gate. Asked Ground to return to gate; was approximately Number 4 for takeoff; turned south on Taxiway Y. Got another call from the 'A' Flight Attendant expressing increase odor and fumes; asked Ground to expedite return to gate; they did. We returned to the gate; customers deplaned; no injuries during deplaning; customers left all belongings on aircraft; medics met the aircraft; took crew's vitals; went to the hospital for further evaluation; tested for TCP's and carbon monoxide. Possible pyrolization of aircraft oil or hydraulic fluid.

Data retrieved from NASA's ASRS site 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.