Narrative:

[Upon] descent into pit; approach assigned descent to 2;000 ft until established; on heading 080 degrees; cleared for ILS runway 10L. Captain (pilot not flying) read back clearance and first officer (pilot flying) set 2;000 ft in the altitude alerter with verification from pilot not flying. Inbound [on the] localizer at 2;000 ft; approach reconfirmed 2;000 ft assigned and switched us to tower. Pilot not flying contacted tower and was informed tower had a low altitude alert. Tower stated 3;000 ft was altitude for approach segment. Pilot flying climbed to 3;000 ft and continued approach. Normal glide slope intercept; normal landing.

Google
 

Original NASA ASRS Text

Title: Air Carrier inbound to PIT ILS Runway 10L was issued 2;000 FT with approach clearance; but was later advised by the Tower of a low altitude alert.

Narrative: [Upon] descent into PIT; Approach assigned descent to 2;000 FT until established; on heading 080 degrees; cleared for ILS Runway 10L. Captain (pilot not flying) read back clearance and First Officer (pilot flying) set 2;000 FT in the altitude alerter with verification from pilot not flying. Inbound [on the] localizer at 2;000 FT; Approach reconfirmed 2;000 FT assigned and switched us to Tower. Pilot not flying contacted Tower and was informed Tower had a low altitude alert. Tower stated 3;000 FT was altitude for approach segment. Pilot flying climbed to 3;000 FT and continued approach. Normal glide slope intercept; normal landing.

Data retrieved from NASA's ASRS site as of April 2012 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.