Narrative:

En route at flight level 320 the cabin flow light came on with the pressurization climbing 1500 feet per minute. I pulled out the QRH and followed the steps for flow light on. The procedures lead us to ask for a lower altitude to see if this would help maintain the cabin. I asked for flight level 260 due to a pressurization problem. Center told us to descend to fl 260 and asked if we were declaring an emergency. I said not at this time; we just need lower. We leveled off at fl 260 and the cabin continued to climb. At this point we knew that we needed to get the aircraft down to 10;000. The cabin 10;000 foot alarm then went off and also the master warnings. I told center that we needed to descend to 10;000 due to loss of pressurization. Center gave us 10;000 immediately and we started a quick descent to 10;000. When the cabin hit 10;000 both I and my co pilot put on our oxygen masks. As we leveled off at 10;000 feet the cabin began to descend back down. During the descent the cabin got as high as 12;500. The masks did not deploy in the back of the aircraft. No passengers or flight attendants were injured. I had asked for fl 260 and I had also asked to divert. Center gave us direct to an airport about 140 miles away. When the cabin alarm had stopped and the cabin was back below 10;000 both of us took off our oxygen masks. At this point we were too low to notify dispatch that we were diverting. The weather was clear VFR and we continued without any further problems. Upon landing and parking the aircraft safely on a run up pad I contacted dispatch to inform them of the diversion and why.

Related reports:

Google
 

Original NASA ASRS Text

Title: An MD-80 pressurization system failed at FL 320. Unable to control the system; the crew declared an emergency; descended the aircraft to 10;000' and the diverted to an enroute airport.

Narrative: En route at Flight Level 320 the cabin flow light came on with the pressurization climbing 1500 feet per minute. I pulled out the QRH and followed the steps for flow light on. The procedures lead us to ask for a lower altitude to see if this would help maintain the cabin. I asked for Flight Level 260 due to a pressurization problem. Center told us to descend to FL 260 and asked if we were declaring an emergency. I said not at this time; we just need lower. We leveled off at FL 260 and the cabin continued to climb. At this point we knew that we needed to get the aircraft down to 10;000. The cabin 10;000 foot alarm then went off and also the master warnings. I told center that we needed to descend to 10;000 due to loss of pressurization. Center gave us 10;000 immediately and we started a quick descent to 10;000. When the cabin hit 10;000 both I and my co pilot put on our oxygen masks. As we leveled off at 10;000 feet the cabin began to descend back down. During the descent the cabin got as high as 12;500. The masks did not deploy in the back of the aircraft. No passengers or Flight attendants were injured. I had asked for FL 260 and I had also asked to divert. Center gave us direct to an airport about 140 miles away. When the cabin alarm had stopped and the cabin was back below 10;000 both of us took off our oxygen masks. At this point we were too low to notify dispatch that we were diverting. The weather was clear VFR and we continued without any further problems. Upon landing and parking the aircraft safely on a run up pad I contacted dispatch to inform them of the diversion and why.

Data retrieved from NASA's ASRS site as of April 2012 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.