Narrative:

At approximately XA40, 75 mi southwest of ZZZ, we received a cabin pressurization and master warning. We noticed the cabin altitude was around 11200 ft. We were then notified by the flight attendant that the masks did drop but no one activated them. We started a descent down to 14000 ft MSL. We complied with all procedures and found that the bleed air switch wasn't to the maximum position. We contacted supervisor of operations control and jointly decided to continue to ZZZ1. I believe the bleed air switch not being at maximum caused the problem.

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Original NASA ASRS Text

Title: A DEHAVILLAND 8-200 AT FL200 EXPERIENCED MASTER WARNING AND CABIN PRESSURE WARNING, WITH PAX MASK DROP. FOUND BLEED SWITCH IN INCORRECT POS.

Narrative: AT APPROX XA40, 75 MI SW OF ZZZ, WE RECEIVED A CABIN PRESSURIZATION AND MASTER WARNING. WE NOTICED THE CABIN ALT WAS AROUND 11200 FT. WE WERE THEN NOTIFIED BY THE FLT ATTENDANT THAT THE MASKS DID DROP BUT NO ONE ACTIVATED THEM. WE STARTED A DSCNT DOWN TO 14000 FT MSL. WE COMPLIED WITH ALL PROCS AND FOUND THAT THE BLEED AIR SWITCH WASN'T TO THE MAX POS. WE CONTACTED SUPVR OF OPS CTL AND JOINTLY DECIDED TO CONTINUE TO ZZZ1. I BELIEVE THE BLEED AIR SWITCH NOT BEING AT MAX CAUSED THE PROB.

Data retrieved from NASA's ASRS site as of July 2007 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.