Narrative:

Dispatch; taxi; takeoff; and climb were normal. Shortly after leveloff at FL360; the lead flight attendant called to advise she and passenger around the emergency exit rows smelled an acrid odor similar to burning rubber. She reported no visible smoke. I advised first officer to start thinking diversion in case things got worse. We decided on ZZZ based on proximity and WX. The cabin attendant called again advising she could not recognize the odor but reported it to be getting worse. I advised her that I was declaring an emergency and that we would divert. I advised center of our intentions. I accomplished the QRH procedures. A jumpseating pilot assisted by making PA's to the cabin and informing our company via ACARS. I briefed the cabin attendant on time remaining and our intent to not evacuate/evacuation unless the situation got worse. The first officer flew the approach and landing. We were able to clear the runway and stop between the runway and the parallel taxiway to allow full access to the aircraft by the fire department. They found no trace of fire or anything else and cleared us to taxi to the gate. Taxi in was normal and after deplaning all passenger; no problems were found by either the fire department or our maintenance. Flight was canceled and passenger re-accommodated.

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Original NASA ASRS Text

Title: B757 DECLARES EMER AND DIVERTS WHEN CABIN ATTENDANT RPTS ACRID ODOR OF UNKNOWN ORIGIN NEAR OVERWING EXITS. INSPECTION REVEALS NO EVIDENCE OF FIRE OR SMOKE.

Narrative: DISPATCH; TAXI; TKOF; AND CLB WERE NORMAL. SHORTLY AFTER LEVELOFF AT FL360; THE LEAD FLT ATTENDANT CALLED TO ADVISE SHE AND PAX AROUND THE EMER EXIT ROWS SMELLED AN ACRID ODOR SIMILAR TO BURNING RUBBER. SHE RPTED NO VISIBLE SMOKE. I ADVISED FO TO START THINKING DIVERSION IN CASE THINGS GOT WORSE. WE DECIDED ON ZZZ BASED ON PROX AND WX. THE CABIN ATTENDANT CALLED AGAIN ADVISING SHE COULD NOT RECOGNIZE THE ODOR BUT RPTED IT TO BE GETTING WORSE. I ADVISED HER THAT I WAS DECLARING AN EMER AND THAT WE WOULD DIVERT. I ADVISED CTR OF OUR INTENTIONS. I ACCOMPLISHED THE QRH PROCS. A JUMPSEATING PLT ASSISTED BY MAKING PA'S TO THE CABIN AND INFORMING OUR COMPANY VIA ACARS. I BRIEFED THE CABIN ATTENDANT ON TIME REMAINING AND OUR INTENT TO NOT EVAC UNLESS THE SITUATION GOT WORSE. THE FO FLEW THE APCH AND LNDG. WE WERE ABLE TO CLR THE RWY AND STOP BTWN THE RWY AND THE PARALLEL TXWY TO ALLOW FULL ACCESS TO THE ACFT BY THE FIRE DEPT. THEY FOUND NO TRACE OF FIRE OR ANYTHING ELSE AND CLRED US TO TAXI TO THE GATE. TAXI IN WAS NORMAL AND AFTER DEPLANING ALL PAX; NO PROBS WERE FOUND BY EITHER THE FIRE DEPT OR OUR MAINT. FLT WAS CANCELED AND PAX RE-ACCOMMODATED.

Data retrieved from NASA's ASRS site as of January 2009 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.