Narrative:

At approx. 24;800 ft pressurization warning light illuminated. Looking at pressurization panel I noted the cabin altitude was slightly above 10;000 ft. Approx. 4.5 psid; cabin rate approx. 500 fpm. First officer (first officer) and I donned oxygen masks. First officer started pressurization warning check list. We initiated a descent to lower altitude. During descent I was unable to establish communications. I determined that donning my mask the hose tangled with my headset cord and both plugs pulled out. During this time flight attendant (flight attendant) tried to contact the flight deck which created some anxiety with them as later reported. The first officer completed the checklist and claimed to have found both bleed switches off. The cabin began pressurizing some time before leveling at 12;000 ft. After leveling at 12;000 ft center called and reported our altitude was 12;400 ft. We reset altimeters and continued to level at 12;000 ft. The cabin pressurized to a normal level. After further evaluation we both concurred there was no further issues. We climbed back to normal cruise altitude and continued to destination.due to the nature of the malfunction; lack of pilot to pilot communications; and repeated attempted contacts by flight attendant caused an unorganized task saturated situation. The pressurization situation didn't fall into a clearly defined category. We had a slowly depressurizing cabin. A cabin altitude that required or shortly would require supplemental oxygen. Further compounding the problem was once the aircraft was pressurizing again we needed to stay on oxygen until getting down to a cabin [altitude] of 10;000 ft.

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Original NASA ASRS Text

Title: Q400 flight crew reported cabin altitude was climbing slowly above normal levels. Bleed switches were found in the off position.

Narrative: At approx. 24;800 ft Pressurization Warning light illuminated. Looking at pressurization panel I noted the cabin altitude was slightly above 10;000 ft. Approx. 4.5 PSID; cabin rate approx. 500 fpm. F/O (First Officer) and I donned oxygen masks. F/O started Pressurization Warning check list. We initiated a descent to lower altitude. During descent I was unable to establish communications. I determined that donning my mask the hose tangled with my headset cord and both plugs pulled out. During this time FA (Flight Attendant) tried to contact the flight deck which created some anxiety with them as later reported. The F/O completed the checklist and claimed to have found both bleed switches off. The cabin began pressurizing some time before leveling at 12;000 ft. After leveling at 12;000 ft Center called and reported our altitude was 12;400 ft. We reset altimeters and continued to level at 12;000 ft. The cabin pressurized to a normal level. After further evaluation we both concurred there was no further issues. We climbed back to normal cruise altitude and continued to destination.Due to the nature of the malfunction; lack of pilot to pilot communications; and repeated attempted contacts by FA caused an unorganized task saturated situation. The pressurization situation didn't fall into a clearly defined category. We had a slowly depressurizing cabin. A cabin altitude that required or shortly would require supplemental oxygen. Further compounding the problem was once the aircraft was pressurizing again we needed to stay on oxygen until getting down to a cabin [altitude] of 10;000 ft.

Data retrieved from NASA's ASRS site 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.