Narrative:

Shortly after takeoff we received a duct mon fault status message. In cruise at 36;000 feet; a left bleed duct warning message appeared with associated closure of the left bleed valve. I transferred the controls to my first officer and began working the applicable QRH procedure. The right bleed valve closed automatically and cabin altitude rose quickly. We began an emergency descent. At 10;000 feet; I completed the QRH unpressurized flight procedure and immediately noticed a smoke smell. The smell did not worsen and I discussed it with the flight attendants; we concluded that it did not warrant an immediate landing. However; I elected to land at the nearest suitable airport. Fire rescue was on scene during our normal landing and a gate was immediately available; where we quickly parked. The cause was mechanical.I would like to see the bleed duct QRH procedure included on the qrc. We would be much more likely to select the unaffected bleed source before they both automatically close and cause a depressurization. In this case; we had extra fuel and we likely would have been able to continue at FL300 or FL310 single pack with no further incident.

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Original NASA ASRS Text

Title: CRJ-700 Captain reported diverting to an alternate airport after receiving a pneumatic bleed duct warning message.

Narrative: Shortly after takeoff we received a Duct Mon Fault status message. In cruise at 36;000 feet; a L Bleed Duct warning message appeared with associated closure of the left bleed valve. I transferred the controls to my first officer and began working the applicable QRH procedure. The right bleed valve closed automatically and cabin altitude rose quickly. We began an emergency descent. At 10;000 feet; I completed the QRH Unpressurized Flight procedure and immediately noticed a smoke smell. The smell did not worsen and I discussed it with the flight attendants; we concluded that it did not warrant an immediate landing. However; I elected to land at the nearest suitable airport. Fire rescue was on scene during our normal landing and a gate was immediately available; where we quickly parked. The cause was mechanical.I would like to see the Bleed Duct QRH procedure included on the QRC. We would be much more likely to select the unaffected bleed source before they both automatically close and cause a depressurization. In this case; we had extra fuel and we likely would have been able to continue at FL300 or FL310 single pack with no further incident.

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.