Every year, schools hold annual science fairs to showcase various students' science projects. Sunscreen science fair projects experiment with sunscreens and sunblocks in relation to the degree of protection they provide against harmful ultraviolet or UV rays. Two kinds of UV rays affect our skin. UV-A which may cause skin cancer and damage, and UV-B which causes tanning and sunburn. By using various materials, methods and sunscreen products, the experiments performed can show if these products are effective and which ones offer the best protection.
SPF Levels in Sunscreens and the Degree of Protection they Provide
Different sunscreens have different SPF or sun protection factor levels. An experiment using the same sunscreen product brands with varying SPF levels can determine whether the different SPF levels correspond to the degree of protection they claim to provide for the skin against UV rays. For this experiment you will need a UV monitor to show and measure the level of protection of sunscreens with different SPF levels. Put sunscreens with different SPF levels on a clear plastic wrap. First, measure the UV levels with no sunscreen protection; this will be your controlled variable. Then measure the UV levels when sunscreens with different SPF levels are spread over the plastic wrap and held against direct sunlight.
Effectivity of Sunscreens or Sunblocks in Spray Form and in Lotion Form
Sunscreens and sunblocks are commonly available in both lotion and spray form. This test aims to show whether one product is better than the other in protecting the skin against harmful UV rays. SPF levels must be the same in the products to be tested against each other. The materials needed are color changing UV beads, clear plastic and a box with the top flaps removed. Put the color changing beads inside the box and cover the top with clear plastic. Put spray sunscreen/sunblock on half of the plastic and sunscreen/sunblock lotion on the the other half. Expose them to sunlight and observe the color changes in the beads. Repeat a number of times for comparison.
Sunscreens vs. Sunblocks
People commonly think that sunscreen and sunblock products are the same. A sunscreen actually just filters ultraviolet rays, while a sunblock acts like tiny little mirrors that reflect and scatter the UV rays, actually blocking them from penetrating the skin. This is an interesting idea for an experiment to show which of the two products is more effective in providing skin protection. For this experiment you can use photo paper, a clear plastic folder and fixer. Put the photo paper in the clear plastic folder and spread the sunscreen and the sunblock on separate but equally sized areas of the clear plastic folder's cover. Expose them under the sun, then use the fixer to see the effects on the photo paper. Do this a number of times to get conclusive results.
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