Narrative:

After takeoff; we were climbing through 2500 ft; 'lavatory smoke' came on EICAS; and the flight attendant called up to say that there was smoke in the cabin and that she could neither see anything or breathe. I advised her that we would be landing immediately. We declared an emergency with approach; the first officer donned her goggles and oxygen mask and ran the emergency checklist for smoke/fumes. I continued to fly the aircraft and talk on the radio; the first officer made a PA to the passenger advising them that we would be returning to land. We were vectored to the ILS runway 27L and landed. Once on the ground and clear of the runway; we checked with the flight attendant and she said the smoke seemed to clear and she was able to breathe; so we decided to continue to a gate to deplane the passenger. The first officer and flight attendant both did an excellent job; we were only in the air for about 8 or 9 mins total. Callback conversation with reporter revealed the following information: the reporter stated it was initially believed deicing fluid had leaked into the air conditioning system and caused the smoke in the cabin. Later advised by a lead technician the smoke was caused by a failed bleed valve; but no clarification on what stage valve and what engine position.

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Original NASA ASRS Text

Title: AN EMB145 ON TKOF CLB AT 2500 FT DECLARED AN EMER AND RETURNED TO THE DEP ARPT DUE TO CABIN ATTENDANT RPT OF SMOKE IN THE CABIN.

Narrative: AFTER TKOF; WE WERE CLBING THROUGH 2500 FT; 'LAVATORY SMOKE' CAME ON EICAS; AND THE FLT ATTENDANT CALLED UP TO SAY THAT THERE WAS SMOKE IN THE CABIN AND THAT SHE COULD NEITHER SEE ANYTHING OR BREATHE. I ADVISED HER THAT WE WOULD BE LNDG IMMEDIATELY. WE DECLARED AN EMER WITH APCH; THE FO DONNED HER GOGGLES AND OXYGEN MASK AND RAN THE EMER CHKLIST FOR SMOKE/FUMES. I CONTINUED TO FLY THE ACFT AND TALK ON THE RADIO; THE FO MADE A PA TO THE PAX ADVISING THEM THAT WE WOULD BE RETURNING TO LAND. WE WERE VECTORED TO THE ILS RWY 27L AND LANDED. ONCE ON THE GND AND CLR OF THE RWY; WE CHKED WITH THE FLT ATTENDANT AND SHE SAID THE SMOKE SEEMED TO CLR AND SHE WAS ABLE TO BREATHE; SO WE DECIDED TO CONTINUE TO A GATE TO DEPLANE THE PAX. THE FO AND FLT ATTENDANT BOTH DID AN EXCELLENT JOB; WE WERE ONLY IN THE AIR FOR ABOUT 8 OR 9 MINS TOTAL. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED IT WAS INITIALLY BELIEVED DEICING FLUID HAD LEAKED INTO THE AIR CONDITIONING SYS AND CAUSED THE SMOKE IN THE CABIN. LATER ADVISED BY A LEAD TECHNICIAN THE SMOKE WAS CAUSED BY A FAILED BLEED VALVE; BUT NO CLARIFICATION ON WHAT STAGE VALVE AND WHAT ENG POS.

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.