Aside from sticky fingers, rogue highlighters, and careless readers, a library’s biggest enemy is dust. The fine particles lead to deterioration, as they absorb and hold moisture—meaning in addition to checking out books and cataloging items, library workers are required to give some dirty tomes the occasional wipe-down.

At the Boston Public Library, The Huffington Post reports, employees give books a bath using a contraption called the Depulvera book cleaning machine. Described as a “mini car wash for books,” it can clean around 12 books per minute. Luckily for library workers, the machine isn’t difficult to use or cumbersome: “It’s compact, simple to use, and can be operated in small spaces—even within stack aisles,” Library Journal explains.

The BPL recently shared a video of the Depulvera on Twitter, explaining that the only books of theirs that receive a deep cleaning are ones from the closed stacks, which typically don’t have dust jackets once they’re requested or digitized. Rare books are fragile, so they require more specialized attention.

Watch the BPL’s “car wash for books” in action below.

— BostonPublicLibrary (@BPLBoston) April 20, 2017

[h/t The Huffington Post]