Narrative:

At cruise altitude of 38;000 ft. The master caution and cabin door light illuminated. Took out the emergency checklist; discussed the issue with the captain. Performed the checklist in detail. Didn't [request priority handling] and elected to continue the 45 minutes to destination. On descent the cabin altitude creeped to 10;200 ft. And the master warning light illuminated with the red cabin altitude annunciations illuminated. The pilot flying acted as [if] a rapid depression was imminent and began increasing our descent rate and deployed the cabin oxygen masks for our passengers. I looked immediately to the pressure controller and noted the cabin altitude stable and about 10;200 ft. I toggled the manual control back to 9;500 ft. And the cabin altitude warning light extinguished. We secured and discontinued using oxygen [for] both pilot and passengers [and] continued to ZZZ and wrote up the system malfunctions.two suggestions: 1; add a note to the checklist identifying the need to constantly monitor the cabin altitude and manually adjust accordingly so as to not inadvertently get a master warning and cabin altitude warning annunciator. And 2; perhaps a random check of the fleet to see if the passenger oxygen masks in fact deploy when activated by a cockpit crew member. [Also] upon deploying the passenger oxygen we noted the infant masks did not release and subsequently did not deploy. Also the masks in the lavatory section failed to drop.

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Original NASA ASRS Text

Title: A Citation Excel First Officer reported rising cabin altitude; master caution; and cabin door warnings which resulted in deploying oxygen. Some masks failed to deploy.

Narrative: At cruise altitude of 38;000 ft. the master caution and cabin door light illuminated. Took out the emergency checklist; discussed the issue with the Captain. Performed the checklist in detail. Didn't [request priority handling] and elected to continue the 45 minutes to destination. On descent the cabin altitude creeped to 10;200 ft. and the master warning light illuminated with the red cabin altitude annunciations illuminated. The pilot flying acted as [if] a rapid depression was imminent and began increasing our descent rate and deployed the cabin oxygen masks for our passengers. I looked immediately to the pressure controller and noted the cabin altitude stable and about 10;200 ft. I toggled the manual control back to 9;500 ft. and the cabin altitude warning light extinguished. We secured and discontinued using oxygen [for] both pilot and passengers [and] continued to ZZZ and wrote up the system malfunctions.Two suggestions: 1; add a note to the checklist identifying the need to constantly monitor the cabin altitude and manually adjust accordingly so as to not inadvertently get a master warning and cabin altitude warning annunciator. And 2; perhaps a random check of the fleet to see if the passenger oxygen masks in fact deploy when activated by a cockpit crew member. [Also] upon deploying the passenger oxygen we noted the infant masks did not release and subsequently did not deploy. Also the masks in the lavatory section failed to drop.

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.