Library Walk-Through Scanners: Understanding the Technology and Security Measures
Have you ever wondered how libraries are able to detect when someone is trying to leave the premises with an unchecked-out book? This article delves into the inner workings of walk-through scanners used in libraries, explaining the various technologies employed to ensure that only properly checked-out items leave the premises.
How Walk-Through Scanners Work in Libraries
Walk-through scanners in libraries primarily rely on RFID (Radio Frequency Identification) technology and barcode systems to detect when a book has been incorrectly removed without being checked out.
RFID Systems
Tags: Each book is equipped with a small RFID tag embedded inside, containing a unique identifier for the book.
Scanners: When a person walks through the exit scanner, the scanner emits radio waves that interact with the RFID tags.
Detection: If the scanner detects an RFID tag that has not been checked out (i.e., it is not registered in the system), it triggers an alarm.
Barcode Systems
Barcodes: Each book is assigned a barcode that is scanned when the item is checked out.
Scanners: Library exit scanners can read these barcodes.
Detection: If a book is not checked out and someone attempts to leave with it, the scanner will recognize that the barcode is not associated with an active loan, thus triggering an alarm.
Deactivating Library Materials
When a book is checked out, there is usually an act of deactivation that occurs. If the book is not deactivated, the scanners will detect it, similar to shoplifting. This process ensures that only properly borrowed items can leave the library.
Some libraries use inserts, often referred to as "telltails," which are typically a white rectangular bandage inside the back cover or slid along the spine of the book. These telltails can be demagnetized by the librarian's machine, disabling the alarm when the book is checked out. When you check out a book, the demagnetization process effectively renders the telltail harmless, allowing you to pass through the exit scanners without triggering an alarm.
Tattle Tape and Other Security Measures
In addition to RFID tags and telltails, tattle tape is another common security measure used in books and magazines. These thin strips are easily placed inside books and can trigger the scanners when they haven't been desensitized. For instance, placing tattle tape in toilet paper rolls is a creative method that has proven effective in certain libraries. These strips are typically impossible to find and demagnetize, making it impossible to bypass the security systems.
Some libraries have also implemented more advanced security measures. For example, DVDs are often stored in locked cases. When a patron checks out a DVD, the case is unlocked. If someone takes a DVD off the shelf without checking it out, the case is automatically locked and inaccessible.
Modern RFID Technology in Libraries
The most up-to-date technology includes placing RFID tags in books, akin to tags on expensive store items. This facilitates efficient inventory management and makes it easier to locate books. In the future, library patrons could place a stack of books on an RFID-enabled pallet and check them all out in a single scan, significantly reducing the labor involved in returning library materials.
Security Proportional to Material Value
Security measures in libraries are directly proportional to the value of the materials involved. Academic libraries often have stronger security measures due to the high value of their collections. At the Rutgers main branch, a security guard was sometimes stationed at the exit, where patrons could be asked to open their bags for inspection as they left.
Conclusion
Walk-through scanners and various security measures used in libraries help prevent theft and ensure that only properly borrowed items leave the premises. Whether through RFID tags, telltails, tattle tape, or other advanced technologies, these systems are designed to maintain the integrity of the library’s collections and uphold the borrowing process.
References and Further Reading
- RFID Systems: 3M Covert Tattle-Tape - Barcode Systems: Bibliotheca Barcode Systems - Academic Library Security: Rutgers Library Security - RFID in Libraries: Duke University Library RFID Technology