Environment
Environment is crucial to the successful storage of books and
other materials such as audio tapes, cd's, and video tapes. It is
necessary to strive for optimum conditions when possible.
Recommended
standards for temperature and humidity are below.
Additional common sense measures such as keeping books away
from water sources, and sources of food and drink spillage are
important.
In addition, when using or storing these materials it is important to remember:
- Restrict handling by children and keep out of reach of pets who like to chew.
- Mishandling by pets or children can cause irreparable damage.
- Don't store where direct sunlight will fall on the material for an extended period of time.
- If you detect evidence of insect infestation, remove the items, and clean thoroughly.
- If you think eggs have been deposited, place items in a freezer for several weeks.
Temperature and Relative Humidity
Control of temperature and relative humidity is of critical importance in the preservation of library materials because unacceptable levels of these contribute significantly to the breakdown of materials. Heat accelerates deterioration by doubling the rate of chemical reactions with each increase in temperature of 18 degrees Fahrenheit. High relative humidity promotes harmful chemical reactions and , in combination with high temperature, encourages mold growth and insect activity. It has been discovered that wide fluctuations in both temperature and relative humidity prove more harmful than a stable but not ideal temperature/humidity combination. While most authorities disagree upon an ideal temperature/relative humidity settings, it is generally recommended that a stable temperature no higher than 70 degrees F and a relative humidity no lower than 30% but not higher than 50% is acceptable.
Light Levels
Light accelerates the deterioration of library and archival materials. It acts acts as a catalyst in their oxidation, leads to weakening and embrittlement of cellulose fibers and can cause paper to bleach, yellow, or darken. It causes media and dyes to fade or change in color. Any exposure to light, even for a brief time, is damaging, and the damage is cumulative and irreversible. Acceptable light levels for light-sensitive materials, including paper, should not exceed 55 lux (5 foot-candles). For less sensitive materials a maximum of 165 lux (15 foot-candles) is permitted . To reduce light damage, several things can be done. Window glass can be coated with a UV filtering film. Drapes and blinds should be closed whenver possible if windows do not have UV filters. If sunlight falls directly upon materials, they should be moved to a more protected location.
Pest Management and Control
A variety of insects and other pests attack binding materials, adhesives, and other substances found in library and archival collections.
The ideal approach to handling pest control needs is integrated pest management or IPM. This approach relies primarily on non-chemical means (such as controlling climate, food sources, and building entry points) to prevent and manage a pest infestation. Chemical treatments are used only in a crisis situation threatening rapid losses or when pests fail to succumb to more conservative methods. IPM strategies would encourage ongoing maintenance and housekeeping to make the environment inhospitable for pests. Activities include building inspection and maintenance; climate control; restriction of food and plants; regular cleaning; proper storage; control over incoming collections to avoid infestation of existing collections; and routine monitoring of pests.