February 16, 2018

Book Cleaning | Product Spotlight

There’s a slow fire burning that threatens to destroy our libraries’ irreplaceable materials. Paper-based books and records are in danger of degradation not only because of their construction but also from improper storage, cleaning, and treatment. While acid-, lignin-, and sulfur-free papers have largely replaced their more fragile wood pulp–based predecessors that were subject to cracking, yellowing, and disintegrating, there is still a danger of acid-free materials—mostly those manufactured after the 1990s—experiencing acid migration when they come into contact with high-acid documents, acid inks, pollutants, or other chemicals.

Then there’s the issue of dust. Dust that covers books and other materials gives off more than the appearance of neglect. It absorbs moisture, increases acid hydrolysis, and causes a quicker breakdown of valuable resources.

Preservation and cleaning practices can greatly extend materials’ lives, along with the use of dedusting vacuums and deacidification sprays that help neutralize the acids in paper and create an alkaline buffer by increasing the pH of acidic paper. Deacidification processes can use water (aqueous) or not (nonaqueous or gas/solvent-based), depending on the materials’ construction, makeup, and type of dyes or inks used during printing.

These five deacidification and vacuum companies specialize in preservation of all kinds of materials, from books and newspapers to maps and other unique documents.

Product: Library Book Vacuum System
Company: Ruwac USA


Eric Potorski is the national sales manager for Ruwac USA, an American-made company using American-made components. The firm focuses on all types of industrial vacuum systems including its customizable Library Book Vacuum System.

The unit features a table designed to handle everything from specialty paper to torn pages. Its silo-style vacuum is compact and has a separate filter system and sound-suppressed turbines for quiet operation. It’s currently being used by institutions such as the Library of Congress, Yale University, and Duke University.

Ruwac’s system is unlike those that employ a power-­rotation brush that can easily damage fragile materials.

“Our system uses the power of a vacuum with minimal force from any brush,” Potorski says. “The vacuum producer is powerful enough to provide vacuum from a distance of over 100′ away from the vacuum table and is controlled through a low-voltage relay.” Potorski adds that the system takes less than ten seconds to process a single book.

The Ruwac Micro Clean filter contains submicron particles and has an average lifespan of more than ten years. The unit’s filter can collect and contain materials such as flour, talc, paint pigments, asbestos, lead, and silica dust.

The ergonomic worktable features a stainless steel manifold with multiple vacuum inlets, offering the option either to slide the book across the manifold or pull down a small hand brush for manual cleaning as well as adjust the strength of the vacuum.

“This proves useful when working on rare books or books where the integrity of the binding is already compromised,” Potorski says. There is also a visual filter at the table so the operator can retrieve pieces of a book that might have been sucked away. Find more information at ruwac.com.

Product: Deacidification spray and solution
Company: Wei T’o

Illinois-based Wei T’o currently offers two nonaqueous deacidification products—Aerosol Spray #111 and Solution #115 deacidification liquids. Both are nonpoisonous, nonflammable, and nonexplosive. Aerosol Spray #111 was designed to prevent aging and embrittlement in books and documents and to preserve and protect paper for up to 400 years. The products neutralize acids, sanitize paper, and infuse paper with an alkaline buffer to prevent reacidification.

Wei T’o’s founder and president, Richard Daniel Smith, says the company also has patents pending on an affordable Comprehensive Preservation and Mass Deacidification Treatment (CPMDT) that will stabilize and prevent further deterioration in the kind of acidic-printing paper that was mainly produced from about 1800 to 1990. Smith says the CPMDT treatments make it possible for cultural heritage institutions such as archives, libraries, and museums to stop the deterioration of acidic paper by single-sheet treatments for manuscripts and works of art and by mass treatments for books and documents.

Smith anticipates Wei T’o’s new CPMDT treatments will transform acidic paper into alkaline-permanent, resulting in strong and flexible materials that will withstand exhibiting and scholarly reading for 500 to 1,000 years if stored at 72°F and 50 percent relative humidity. Request more information at weito.com.

Product: Depulvera
Company: Oracle


The Italian-made Depulvera by Oracle is an automatic book cleaning system that dusts about 12 books per minute. It’s compact, simple to use, and can be operated in small spaces—even within stack aisles. The external Hepa filter protects operators from harmful dust, too, and can clean items with maximum dimensions of 5.5″ x 11″ x 15″. An even smaller version, the Pulvisina, can be placed on a desk or cart and, with one-person operation, can clean up to six books per minute with a maximum dimension of roughly 4″ x 13″ x 13″. The L’aura maxi version is a semiautomatic machine that dusts folders, files, and large-format books of up to 8″ x 23″ and requires two passes for cleaning, making its processing time about six items per minute. The Oracle website (depulvera.com) includes a form to request more information.

Product: Bookkeeper
Company: Preservation Technologies

Pennsylvania-based Preservation Technologies, L.P. (PTLP), developed its patented Bookkeeper acid neutralizing process in 1992 and purports to be the only deacidification method to meet the standards of the Library of Congress as well as current and projected OSHA, FTC, and EPA consumer and environmental requirements with a deacidification process that can increase the life expectancy of books and records up to five times.

With facilities worldwide, PTLP receives more than 550,000 assets from library and archival collections annually to be deacidified individually or in small batches, with the final pH ranging from seven to ten. Bookkeeper infuses a nontoxic alkaline buffer into paper to neutralize harmful acids and doesn’t employ solvents or gases that can damage inks, adhesives, paper, or binding fabrics. It leaves no harmful chemical residue in the paper, eliminating the need for after-treatment off-gassing to remove odors or humidification to restore moisture to the paper.

The process is safe for all kinds of paper-based materials, such as newsprint, books, postage stamps, maps, prints, even handwritten documents, and it doesn’t affect inks, adhesives, or covers. Bookkeeper works by suspending microscopic alkaline magnesium oxide buffer particles in an inert blend of nontoxic, waterless, fluorinated liquid material that can be applied through either dipping or spraying. Once applied to paper, the alkaline particles bond with the paper structure, and the inert liquid evaporates without wetting or swelling the paper fibers.

The Bookkeeper Spray System can be used to treat maps, posters, and other large documents and includes a pressure tank and spray gun with nozzle tip and an air compressor to operate the tank’s agitator and disperse the buffer. Bookkeeper is also offered as a stand-alone spray for single items. It’s available in 150g, nonaerosol, refillable bottles, and 900g. refillable bottles that never expire or clog. Preservation Technologies’ website is ptlp.com/en.

Product: Nilfisk GM80
Company: Nilfisk


Nilfisk offers a complete line of industrial vacuum cleaners, and its Nilfisk GM80 is the model most often used by libraries and museums, including the Penn Museum in Philadelphia, which uses the Nilfisk GM80 in its artifact lab to treat the coffin containing the mummy Nespekashuti. It’s a single-phase, variable-speed light industrial vacuum that includes a multistage filtration system with a paper dust bag, main filter, and microfilter. Lightweight, portable, and quiet, GM80 vacuums are known for their durability. Variable speed control allows for cleaning books, shelves, and general purpose cleaning; users can vary the motor speed to adjust the suction by turning a dial to vary the airflow from zero to 87 cfm, or zero to 100% of machine power, and every increment in between. This option is ideal for general upkeep around delicate museum artifacts as well as rare books and manuscripts found in many libraries.

It comes standard with a detachable trolley, a 6’6″ plastic hose, two straight steel wands, paper bags, a 30′ cord, a 3″ round brush, a crevice cone, a 5″ upholstery nozzle, a combination floor nozzle, and the optional museum kit with microtools that can be used to clean small spaces gently. Find out more at nilfiskcfm.com.

Denice Rovira Hazlett (denicehazlett.com; @charmgirl on Twitter) is a feature, profile, and fiction writer

This article was published in Library Journal's November 15, 2016 issue. Subscribe today and save up to 35% off the regular subscription rate.

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