Light is very important to conservation labs: the right amount of the right kind of light particularly influences fine detail work and color matching. However, as anyone familiar with preservation issues knows, light is also The Enemy. Damaging UV light may be the part of the spectrum that gets the most attention, but any light causes cumulative damage to paper-based materials over time.

Our lab workspace is mainly lit by overhead fluorescents with UV filters on them. Likewise, our large, lovely window is also covered with UV-filtering film. We store our colored tissues in flat files nearby, so it’s easy to hold them up to the window and take advantage of the natural light when selecting the right color for a repair.

In spite of our precautions regarding UV filters, the lab is still flooded with more light than is safe for paper-based materials over the long term, as the framed poster above regularly reminds us. The colors have faded and shifted over time, simply from being exposed to the ambient light we need to do our daily work.

Aware of light’s insidious and relentless power, we take whatever precautions we can when working with Special Collections and Archives materials in the lab by covering them up with an enclosure, sheet of blotter, or other light-blocker when we are not actively working on them.
As part of our responsibilities as a land grant institution, we are charged with providing education and outreach services to the public. In the lab, this charge manifests as preservation consultations for Iowa residents and institutions. When it comes to light exposure, we strongly encourage our visitors not to display treasured, original photographs or documents from their personal collections in heavily used or brightly lit rooms. Light damage is irreversible, so the precautions are worthwhile. Originals may be stored in enclosures or in dark drawers or cabinets, and displayed only on special occasions. Alternatively, originals may be scanned and a surrogate printed for display purposes, while the original is stored safely out of the light. If originals must be displayed, then we strongly recommend framing with a UV-filtering plexi, with the caveat that this will only partially mitigate one form of light damage.