How Effective Is Your Sunscreen?
How effective is your sunscreen?
Student teams design and conduct quality-control experiments to test the reliability of several ultraviolet protection factors. Students use UV-detecting beads in their experimental designs to test the effectiveness of various types of sunscreens and sunblock. For example, they might examine zinc oxide nanoparticles versus traditional organic sun protection factors. UV intensity is quantitatively measured by UVA and UVB Vernier sensors, and students record and graph their results. By designing and conducting this experiment, students compare various substances, while learning about quality control.
This activity provides students with a lab experience in engineering design for quality control. Also, by working in groups, students learn to acknowledge and implement ideas from all members, much like engineers do in industry. The activity also includes chemical and environmental engineering connections—examining the chemical reactions that are involved when chlorofluorocarbons react to break down the ozone layer and the implications to overall public health when pollution causes this to occur, as well as laboratory-based experimentation as part of the design of new products and processes.
After this activity, students should be able to:
- Explain how to conduct a quality control experimental design.
- Describe how UVA and UVB sensors can be used to measure UV intensity.
- Design a controlled one-variable experiment.
- Test and evaluate previously determined experimental values.