Narrative:

At FL390 both pilots simultaneously experienced very strong chemical odor/fumes. We both could feel it quickly affecting our lungs. We both went on oxygen; declared an emergency; turned towards a nearby airport and began running the smoke and fume checklist. We notified dispatch via ACARS of a divert; requested fire and rescue meet us. We checked the weather at the divert airport and proceeded direct runway for a visual approach.

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Original NASA ASRS Text

Title: A B767-300 Forward Recirculation Fan failed in flight causing very strong chemical odor/fumes so; after donning oxygen masks; an emergency was declared and the flight diverted to a nearby airport.

Narrative: At FL390 both pilots simultaneously experienced very strong chemical odor/fumes. We both could feel it quickly affecting our lungs. We both went on oxygen; declared an emergency; turned towards a nearby airport and began running the smoke and fume checklist. We notified Dispatch via ACARS of a divert; requested fire and rescue meet us. We checked the weather at the divert airport and proceeded direct runway for a visual approach.

Data retrieved from NASA's ASRS site as of July 2013 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.