General Safety Guidelines

UV sensitive beads on a pipe cleaner.

Electromagnetic radiation beyond the visible spectrum cannot be seen by humans. Your mission in this activity is twofold. Your first goal is to find out exactly where ultraviolet radiation is found. That is to say, find out what sources give off UV light. Your second goal is to find out what can and can't block UV radiation.

To know when UV radiation is present, we must find something that is sensitive to UV radiation and that produces a change that we can observe. To do this, you first need some simple equipment, such as a few beads that contain dyes that are sensitive to ultraviolet light, that is, when UV light hits the beads, they will change color. You also need a piece of pipe cleaner to hold the beads. Now you are on your own. With the beads as your ultraviolet light indicator, decide how you might systematically check whether UV is present, and how you might systematically check whether something really screens out ultraviolet light. Think about such things as your UV-blocking sunglasses, window glass, sunscreen, staying in the shade, or anything else you can think of. Be sure to record your plan for each experiment and all your observations. Try to control every variable that could be critical of your experiments so that you can discuss ideas with your classmates of where UV is found, and what works and what does not work to block ultraviolet radiation.