Narrative:

In route at cruise altitude of FL200; we were alerted via EICAS of a bleed 2 failure. Bleed 1 was already inoperative. I gave the first officer (first officer) the radios; asked him to request a descent; and began to run QRH 2.5 for bleed 2 fail. ATC assigned us an altitude of 16;000 ft. Knowing that this was not low enough; and with the cabin altitude rising; I instructed the first officer to [notify ATC of our situation] due to a pressurization issue and see if we could get a lower altitude. We were assigned 10;000 ft. And the first officer set this as our target altitude.by this time; I had cycled bleed 2; per the QRH; and the bleed had come back online. With the reset successful and pressurization returning; we cancelled the emergency and leveled off at our originally assigned 16;000 ft. After the situation was under control; I contacted the fas and asked if they had noticed anything odd. Neither of them had; and even after I informed them of the momentary loss of pressurization; they informed me that neither they nor the passengers seemed to notice anything. We determined that our fuel was still sufficient to continue; and proceeded without issue.

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Original NASA ASRS Text

Title: EMB-175 Captain reported loss of pressurization during cruise requiring emergency descent.

Narrative: In route at cruise altitude of FL200; we were alerted via EICAS of a Bleed 2 Failure. Bleed 1 was already INOP. I gave the First Officer (FO) the radios; asked him to request a descent; and began to run QRH 2.5 for Bleed 2 FAIL. ATC assigned us an altitude of 16;000 ft. Knowing that this was not low enough; and with the cabin altitude rising; I instructed the FO to [notify ATC of our situation] due to a pressurization issue and see if we could get a lower altitude. We were assigned 10;000 FT. and the FO set this as our target altitude.By this time; I had cycled Bleed 2; per the QRH; and the bleed had come back online. With the reset successful and pressurization returning; we cancelled the emergency and leveled off at our originally assigned 16;000 ft. After the situation was under control; I contacted the FAs and asked if they had noticed anything odd. Neither of them had; and even after I informed them of the momentary loss of pressurization; they informed me that neither they nor the passengers seemed to notice anything. We determined that our fuel was still sufficient to continue; and proceeded without issue.

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.