There's currently only one pure volume-based scan in the system -- the Volume Surge scan. It identifies stocks which traded more than three times their average daily volume. While it may be used alone it's probably most useful when used in a Combo Scan. However, that's not truly necessary because you can also sort any scan's results by "Volume vs. Average"

The Parabolic Rise and Pocket Pivot scans also take volume into consideration as a factor in their calculations.