Pressurization problem dictated descent and diversion to rno. Emergency declared for descent.

Attributes
ACN	181782
Time
Date	199106
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : rno
State Reference	NV
Altitude	msl bound lower : 32000 msl bound upper : 32000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zoa
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : instrument pilot : commercial
Experience	flight time last 90 days : 97 flight time total : 13500 flight time type : 5500
ASRS Report	181782
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : commercial pilot : atp pilot : instrument
Experience	flight time last 90 days : 65 flight time total : 2739 flight time type : 2
ASRS Report	182220
Events
Anomaly	aircraft equipment problem : critical
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : declared emergency flight crew : regained aircraft control other
Consequence	Other
Supplementary
Primary Problem	Aircraft
Air Traffic Incident	other

Narrative:

Flight from sacramento to salt lake city. We were climbing through FL320 for 330 when our cabin altitude warning horn blew indicating a cabin altitude of plus 10000'. After trying our backup systems that did not stop the cabin rise we declared an emergency and asked for a vector to reno, nv, (30 mi away). We performed all of our appropriate checklists, put on oxy masks, descended as soon as possible for our landing. During the descent, we were given several intermediate level off altitudes from oakland center (apparently for traffic). During the descent, cabin altitude rose to above 15000' and the oxy masks automatically deployed. The F/as did a superb job with the passengers (85). The F/a in charge interviewed each passenger personally. Only one woman experienced an ear block that we could tell and she was treated by paramedics. After checking the pressurization system on the ground we could not find an apparent reason for the problem. I suspect a door sel or a stuck pack valve (a/C pack) but there is no way to tell for sure. The entire emergency descent procedure went very well and the passengers remained calm. We landed in reno, I did not request emergency equipment since it was inappropriate.

Original NASA ASRS Text

Title: PRESSURIZATION PROBLEM DICTATED DESCENT AND DIVERSION TO RNO. EMERGENCY DECLARED FOR DESCENT.

Narrative: FLT FROM SACRAMENTO TO SALT LAKE CITY. WE WERE CLBING THROUGH FL320 FOR 330 WHEN OUR CABIN ALT WARNING HORN BLEW INDICATING A CABIN ALT OF PLUS 10000'. AFTER TRYING OUR BACKUP SYSTEMS THAT DID NOT STOP THE CABIN RISE WE DECLARED AN EMER AND ASKED FOR A VECTOR TO RENO, NV, (30 MI AWAY). WE PERFORMED ALL OF OUR APPROPRIATE CHKLISTS, PUT ON OXY MASKS, DSNDED ASAP FOR OUR LNDG. DURING THE DSNT, WE WERE GIVEN SEVERAL INTERMEDIATE LEVEL OFF ALTS FROM OAKLAND CTR (APPARENTLY FOR TFC). DURING THE DSNT, CABIN ALT ROSE TO ABOVE 15000' AND THE OXY MASKS AUTOMATICALLY DEPLOYED. THE F/AS DID A SUPERB JOB WITH THE PAXS (85). THE F/A IN CHARGE INTERVIEWED EACH PAX PERSONALLY. ONLY ONE WOMAN EXPERIENCED AN EAR BLOCK THAT WE COULD TELL AND SHE WAS TREATED BY PARAMEDICS. AFTER CHKING THE PRESSURIZATION SYS ON THE GND WE COULD NOT FIND AN APPARENT REASON FOR THE PROB. I SUSPECT A DOOR SEL OR A STUCK PACK VALVE (A/C PACK) BUT THERE IS NO WAY TO TELL FOR SURE. THE ENTIRE EMER DSNT PROC WENT VERY WELL AND THE PAXS REMAINED CALM. WE LANDED IN RENO, I DID NOT REQUEST EMER EQUIP SINCE IT WAS INAPPROPRIATE.

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.