Assuming your data starts in A1, enter this formula:

=IF(ISERROR(INDEX($B$1:$B$7,SMALL(IF($E$1:$E$7=30, ROW($E$1:$E$7)),ROW(1:1)))),"",INDEX($B$1:$B$7,SMA LL(IF($E$1:$E$7=30,ROW($E$1:$E$7)),ROW(1:1))))

Enter it as an array formula, using Conrol Shift and Enter. Copy down as
far as your data goes.