Preserving books for posterity

THE Department of Arts and Culture has invested R21million in the preservation of more than 500000 books and other material at the National Library of South Africa's Pretoria and Cape Town campuses.

The library has been collecting books, newspapers, journals, magazines, maps and government publications for the past 200 years.

About 300000 of the priceless materials are in danger because of irreversible paper ageing and acidity.

Over time acid causes paper to become fragile. Atmospheric pollution and chemicals used in paper manufacturing also contribute to paper deterioration. This is why the national library set de-acidification in motion.

De-acidification is the chemical neutralisation of acid in paper, which slows its deterioration, prolonging the life of the paper to up to 150 years. The treatment does not reverse damage nor does it restore the paper to its original state, but it stops further damage.

According to National Library preservation services unit manager Douwe Drijfhout the method provides long-term stability of treated material, processes books without damage to their bindings and provides the highest level of benefit while posing the least amount of risk.

"Several mass de-acidification systems have been developed over the years and are used at national libraries and archives throughout the world," Drijfhout said.

Preservation service production manager Isaac Nkadimeng said they chose the US developed Bookkeeper method because it adhered to safety, environmental and archival requirements.

He said this method took place in a vertical cylinder in which books are placed upright with the spines against a rod in the centre of the cylinder.

"Specially designed holders keep the covers wide open and then de-acidification fluid is pumped into the chamber. Afterwards the fluid is pumped away for reuse and the material is vacuum dried. The books are then placed in a well ventilated room for 24 hours, allowing the material to absorb air until moisture balance is reached," Nkadimeng said.

He said the method was suitable for all paper material, including bound and unbound documents, printed and handwritten materials.

The equipment was installed at the National Library's Pretoria campus in August 2009 and can process more than 30000 items a year. More than 10000 books have been de-acidified so far.

l The Arts and Culture Department is a crucial nation-building partner in the South African Literary Awards, which honours emerging and established authors. Other partners are wRite Associates, Nutrend Publishers, Sowetan and the Aggrey Klaaste Nation Building Foundation.