Inventory Item History Purge process

We have issues with active items getting purged when we run this purge process.  We need a sql or report to identify which active items will be picked up in this process, so we can prevent them from being purged... and then we would like to find out what we can do to prevent them from being chosen.  Is there a specific process that is not being completed prior to the purge?  Are items at a specific status that allow them to be selected?  Is our Purge criteria not specific enough to prevent this from happening?   Our user stated this