What are UV Rays?
Before you say, “Omigod, I don’t want to read about science,” this will be quicker than putting on sunscreen to block those pesky UV rays. The above chart of the electromagnetic spectrum (remember high school science?) shows that UV rays are to the left of visible violet light, hence the name ultraviolet, and are in the direction of increasing energy. That’s why UV rays are dangerous for sunburn and for fading of artwork even though they are only 3% of the sun’s rays that reach the Earth.
If you’re wondering if your art is safe in indirect daylight, there are two ways to measure UV rays. We have a UV meter to measure UV rays at a given moment. But another useful tool is the blue card which records the cumulative effects of fading over a period of time. This card was placed at the Annex on April 23, 2010. It has several strips of fabric dyed with a range of light sensitive blue dyes. The card is attached halfway behind a picture frame and the photo shows how the lowest blue strip has faded since its placement in April. Remember, art is meant to be viewed and the final judgment about art placement is balancing the factors of your desire to view the art, the type of art, value of art and environmental conditions.
Different artworks have various levels of UV sensitivity to fading. For example, we’ve all seen color photographs that have grown pale with age. Watercolors are sensitive to fading because the layer of paint and pigment is so thin. Oil paintings are fairly robust but are ultimately subject to fading as well.
1. UV rays are not just in direct sun but also in indirect light.
2. Protect artwork with UV resistant glass. This is 98% to 99% filtering so there is still 1% causing fading.
3. Keep artwork out of direct sunlight and high light situations