Flooded with light - studying the effects of light on museum collections

Light has the potential to cause damage to objects in museum collections. The Smithsonian’s Museum Conservation Institute (MCI) Senior Research Scientist Marion Mecklenburg has worked with the Smithsonian American Art Museum, the National Portrait Gallery, and the Hirshhorn Museum and Sculpture Garden to investigate light levels, especially in recently constructed or renovated exhibits and collection spaces that take full advantage of natural lighting via skylights and windows to enhance the visitor’s experience. Although accommodations and preventive measures have been made for controlling the light intensity and spectrum, especially ultraviolet radiation, visible light levels recorded in some galleries and collection storage exceed accepted museum standards. Are these standards valid? Are collections in danger of fading? MCI researchers are experimentally testing the fading of materials under widely different light intensities. With an understanding of fading and its interaction with temperature, relative humidity, and ambient or reduced oxygen levels, we will develop guidelines for acceptable lighting levels. These guidelines complement our recommendations for safe temperature and relative humidity levels in exhibits and collections.