Newspapers from the mid-19th century onwards are printed on inexpensive, wood pulp paper that is not manufactured for longevity. These newspapers are inherently acidic due to the chemical instabilities of low-quality wood pulp papers. Good storage conditions are critical to the preservation of acidic papers, but the following guidelines apply to all newspapers, including those from before the mid-19th century, which are printed on better quality paper:
- A cool (room temperature or below), relatively dry (about 35% relative humidity), clean, and stable environment (avoid attics, basements, and other locations with high risk of leaks and environmental extremes)
- Minimal exposure to all kinds of light; no exposure to direct or intense light
- Distance from radiators and vents
- Storage of newspapers in flat storage boxes
- Supportive protective enclosures such as: acid-free and lignin-free buffered folders, flat boxes with lids the same depth as the base, and stiff boards for "board-setting" (sandwiching neat stacks between preservation-quality boards).
- Polyester sleeves are not recommended for newspaper storage, as they carry a static charge that can damage brittle newspaper. Polyester sleeves also do not have an alkaline buffer, which could provide a desirable neutralizing effect on acids in paper. They also add considerable weight and bulk to storage.
