Ultraviolet Spectra Information

Your skin is an excellent detector of ultraviolet (UV) radiation. When you expose bar skin to sunlight, your skin will either turn brown (a suntan) or red (a sunburn). These responses by your skin are a signal that the cells under your skin are being assaulted by UV radiation. UV radiation wavelengths are short enough to break chemical bonds in your skin tissue and with over prolonged exposure, your skin may wrinkle or skin cancer may appear.

There is a safer way to detect UV…by using the UV Beads. These plastic beads contain a harmless chemical which changes color when exposed to UV radiation. The colors that develop depend on the wavelength of the UV radiation.

Fun Things You Can Do To Demonstrate UV Exposure

Place a selection of UV beads near a fluorescent light. Do any of the beads change color? Can you get a sunburn or a tan by sitting next to a fluorescent light?

Take the UV beads outside, but not into direct sunlight. Do any beads change color? Is there UV radiation in the shade?

Now place the beads in direct sunlight. What do you notice about the intensity of the beads’ color?

Place the beads in direct sunlight and place a sheet of thin plastic over them and note the colors. Now spread on a layer of a commercial sun block on the plastic and note if any of the bead colors are reduced. Try this experiment with a number of sun blocks with different ratings. Which brand and which ratings block solar UV most effectively?

If you are able, take the beads to a tanning parlor and expose them to the UV radiation from the tanning lamps. How does this UV radiation compare to the direct sun’s UV?

If you take a trip into the mountains, take the beads along and see if there is any difference between colors at high altitudes and at sea level.

These beads contain different pigments that change color when exposed to ultraviolet light from any source – including the sun. The beads are all white in visible light. In UV light, depending on the pigment added to each bead, you will see different colors. Each bead will change color about 50,000 times before the pigment will no longer respond to UV light.

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Here are some additional experiments for upper grade students you can try:

Does the glass in your car shield you from UV radiation? Is the glass in the windshield the same as the glass on the side windows?

Do sunglasses shield you from UV? Do they all work equally well?

Devise experiments to see how well sunscreen works to protect you from UV.

Experiment which different types of materials, like paper, sandwich bags, etc to see what blocks UV and what does not.

Questions you might pose to students for their Lab Notebook:

What colors do the various beads turn when they are exposed to UV radiation?
Which of these colors are most intense? Which are least?
Write a paragraph to describe an experiment you could do with the beads – so we can look at your initial plan. You must demonstrate that you have an initial plan.

Give each student a pipe cleaner and 3-4 beads..they can string their own UV Detection bracelet…wear it around school…take it home over the weekend, experiment and report back!

The UV detection beads (known as) “SUN-BOW Beads” can be purchased from the following source:

Rainbow Symphony, Inc.

6860 Canby Ave Ste 120

Reseda, CA 91335 USA

Tel 800-821-5122

Tel 818-708-8400

Fax 818-708-8470