Narrative:

After diverting to ZZZ earlier in day for the same problem; we departed for ZZZ1. During climb we again experienced smoke in the cabin and multiple smoke detector activations. After the problem cleared as we expected we continued to ZZZ1. Everything returned to normal for the next 25 mins. As we arrived in ZZZ1 airspace we were put into holding. As we approached the hold; the cabin was again filling with smoke and smoke detectors activated. I was unwilling to hold and with ZZZ1 backed up; the only way to get priority was to declare an emergency. Again we believe no regulations were violated; but would like to be afforded protection in the safety program.

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Original NASA ASRS Text

Title: B757 REPORTS DIVERTING FOR CABIN SMOKE. SMOKE IS AGAIN EXPERIENCED ON NEXT LEG WITH FLIGHT CONTINUING TO DESTINATION AFTER SMOKE CLEARS. EMERGENCY DECLARED DURING ARRIVAL AFTER SMOKE REAPPEARS.

Narrative: AFTER DIVERTING TO ZZZ EARLIER IN DAY FOR THE SAME PROB; WE DEPARTED FOR ZZZ1. DURING CLB WE AGAIN EXPERIENCED SMOKE IN THE CABIN AND MULTIPLE SMOKE DETECTOR ACTIVATIONS. AFTER THE PROB CLRED AS WE EXPECTED WE CONTINUED TO ZZZ1. EVERYTHING RETURNED TO NORMAL FOR THE NEXT 25 MINS. AS WE ARRIVED IN ZZZ1 AIRSPACE WE WERE PUT INTO HOLDING. AS WE APCHED THE HOLD; THE CABIN WAS AGAIN FILLING WITH SMOKE AND SMOKE DETECTORS ACTIVATED. I WAS UNWILLING TO HOLD AND WITH ZZZ1 BACKED UP; THE ONLY WAY TO GET PRIORITY WAS TO DECLARE AN EMER. AGAIN WE BELIEVE NO REGS WERE VIOLATED; BUT WOULD LIKE TO BE AFFORDED PROTECTION IN THE SAFETY PROGRAM.

Data retrieved from NASA's ASRS site as of May 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.