Emb-135 flight crew reported a GPWS event during approach to oak airport.

Attributes
ACN	1630116
Time
Date	201903
Local Time Of Day	0601-1200
Place
Locale Reference	OAK.Airport
State Reference	CA
Aircraft 1
Make Model Name	EMB ERJ 135 ER/LR
Operating Under FAR Part	Part 135
Flight Phase	Initial Approach
Flight Plan	IFR
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Multiengine Flight Crew Instrument Flight Crew Private Flight Crew Commercial
Person 2
Function	Pilot Not Flying First Officer
Qualification	Flight Crew Commercial Flight Crew Private Flight Crew Instrument Flight Crew Multiengine
Events
Anomaly	Deviation - Procedural Clearance Inflight Event / Encounter CFTT / CFIT

Narrative:

Aircraft X was being vectored to the west for the ILS 12 and was level at 3;200 [feet] and instructed to descend to 3;000 [feet]. This engaged the aircraft GPWS and an aural warning sounded. I began a climb from the assigned altitude of 3;000 [feet] to 3;200 [feet] and informed oak approach. I descended from there; continuing the approach without conflict.

Original NASA ASRS Text

Title: EMB-135 flight crew reported a GPWS event during approach to OAK airport.

Narrative: Aircraft X was being vectored to the west for the ILS 12 and was level at 3;200 [feet] and instructed to descend to 3;000 [feet]. This engaged the aircraft GPWS and an aural warning sounded. I began a climb from the assigned altitude of 3;000 [feet] to 3;200 [feet] and informed OAK approach. I descended from there; continuing the approach without conflict.

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.