Narrative:

During power reduction after level off forward lav smoke alarm went off. There was a burnt oil smell and haze present in the cabin. We ran the checklist and the smell and haze went away. The flight attendant checked the lav and did not find anything. When the power was reduced to descend into ZZZ it came back and an emergency was declared. Upon switching bleeds from the engines to APU; the smell went away. Taxied to the gate with a fire truck following. The aircraft was inspected by maintenance and no problems were found. I flew the aircraft on another 3 hour round trip and had no other problems. The flight attendants were taken to the doctor to be examined but were released to return to work after a 2 hour rest.

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Original NASA ASRS Text

Title: A CRJ700 FLT CREW EXPERIENCED FUMES IN THE CABIN AFTER FWD LAV SMOKE ALARM ACTIVATED. THEY DECLARED AN EMER AND LANDED NORMALLY.

Narrative: DURING POWER REDUCTION AFTER LEVEL OFF FORWARD LAV SMOKE ALARM WENT OFF. THERE WAS A BURNT OIL SMELL AND HAZE PRESENT IN THE CABIN. WE RAN THE CHKLIST AND THE SMELL AND HAZE WENT AWAY. THE FLT ATTENDANT CHECKED THE LAV AND DID NOT FIND ANYTHING. WHEN THE POWER WAS REDUCED TO DESCEND INTO ZZZ IT CAME BACK AND AN EMER WAS DECLARED. UPON SWITCHING BLEEDS FROM THE ENGS TO APU; THE SMELL WENT AWAY. TAXIED TO THE GATE WITH A FIRE TRUCK FOLLOWING. THE ACFT WAS INSPECTED BY MAINT AND NO PROBS WERE FOUND. I FLEW THE ACFT ON ANOTHER 3 HOUR ROUND TRIP AND HAD NO OTHER PROBS. THE FLT ATTENDANTS WERE TAKEN TO THE DOCTOR TO BE EXAMINED BUT WERE RELEASED TO RETURN TO WORK AFTER A 2 HOUR REST.

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.