Environmental Control

Practical measures to improve the environment
In many places heating, ventilating, and air conditioning systems (HVAC) may be too costly to install and maintain or may have to be restricted to specific collections. Nevertheless, there are many rudimentary measures and precautions that can improve a library’s environment and protect collections.

A first step in all efforts to improve the environment should be sealing the structure. This step alone will improve the physical condition of the building by reducing air infiltration, pest access, heating loss or heat gain, and air and particulate pollution. Making the building watertight will also reduce the sources of moisture within the structure and may significantly reduce relative humidity levels.

• Use draft excluders and weatherstripping to make the building weathertight.
• Ensure windows and doors fit securely.
• Ensure good air circulation by appropriate use of fans and windows.
• Use dehumidifiers and humidifiers to reduce or increase relative humidity.
• Use insulation methods to reduce heat gain or loss.
• Use UV-filters on windows and fluorescent lighting.
• Use screens, blinds, shutters (preferably outside the windows, as this reduces solar heat gain), and heavy curtains to keep out direct sunlight.
• Ensure storage facilities are dark.
• Ensure buildings are properly maintained to keep out dampness during rainy periods.
• Use close-fitting enclosures (boxes and envelopes) wherever possible to protect important and valuable library material. These can create a microclimate around the object, which delays the effects of changes in temperature and relative humidity. They also shield the item from light, and can act as a buVer against atmospheric pollutants and prevent particulate deposits.
• Be aware that while trees and vegetation near buildings can reduce heat gain, they can also encourage insect and pest activity.
• Locate plumbing and heating pipes outside storage areas.
• Locate sanitary premises and sinks outside storage areas.