IPC-A-22 - Gerber Files UL Recognition Test Pattern Document #: IPC-A-22 Revision Original Version Product Type Gerber Files Released: 02/01/1996 Language English Current Revision Recognition vehicle for UL-796 and UL-746. Tests for conductor width plating quality-PTH, flammability, etc. (1 pc. 41 x 57 cm 1:1). Gerber Format.