Figure out why books go missing

I have noticed that several of the books (particularly in the QA300s section) I like to use in Hayden have gone missing or on search from the stacks. Some have not been found, even though they went on search last semester. The books that have gone missing were, in my opinion, some of the best references in that section of the library, so I feel it is in the best interest of the library to prevent this from happening in the future.

I think a short investigation might help reveal some issues. My suspicion is that the detectors in Hayden might need maintenance -- I know from experience that I have accidentally placed books in my backpack and walked out with no issue. (I did check them out later once I found out). So it may be possible that more books are accidentally going missing from Hayden for the same reason.

This is all speculative, but I think that a quick investigation of the missing books might either reveal that there is no problem or else point to a solution.