Does Clothing Made From Sun-ProtectiveMaterial Provide
More Effective Protection From the Sun's Harmful Rays Than Clothing That Is Not Made Specifically As Sun-Protective Clothing?

Bernie C.
5th Grade, Indian Harbor Montessori, Indian Harbor Beach Florida
Teacher: Sabrina Bethurum

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Hypothesis:
I predict that clothing made from sun-protective material will provide more effective protection from the sun’s harmful rays than material that is not made specifically as sun-protective clothing. The sun-protective material has an ultraviolet protection factor (UPF) rating of 25, while the regular material has a UPF rating of 5. The sun-protective material will have 25 times more protection against UV radiation than unprotected skin, whereas the non sun-protective material will provide only 5 times more protection against UV radiation than unprotected skin.

I think that repeated washings may have an effect on the sun-protective quality of fabric; I think that even after the non sun-protective fabric and the sun-protective fabric are washed 19 times each, the sun-protective fabric will still provide more effective protection against the sun’s harmful rays.

I think that after both types of material are washed 25 times each, the sun-protective fabric will still provide more effective protection from the sun’s harmful rays than clothing that is not made specifically as sun-protective clothing.

I predict that the non sun-protective fabric with sun protective laundry additive (or optical brightener) will provide more effective protection from the sun’s harmful rays than the clothing made specifically from sun-protective material. The sun-protective laundry detergent boosts the protection level of the clothing to a UPF rating of 30, whereas the sun-protective clothing has a UPF rating of only 25.

I think that the sun-protective fabric will provide more effective protection against exposure to the sun’s harmful rays than the non sun-protective fabric with laundry additive when washed 19 times each. The sun-protective laundry detergent proclaims that one treatment lasts 20 washings, but I predict that, by 19 washings, the sun-protective effects of the laundry additive will slowly wear off and make the fabric less sun-protective than the fabric manufactured as sun-protective.

When the materials are washed 25 times each, and additional optical brightener is added to the non sun-protective fabric with laundry additive at 20th wash, I predict that the non sun-protective fabric with the laundry additive material will offer more protection against the sun’s deadly UV rays than the sun-protective and non sun protective materials.
(Professor Sunny's note: Bernie tested his fabrics using sun-sensitive paper, a light meter, and a spectrophotometer.)

Conclusion:
The sun-protective material provided the best overall protection from the sun’s harmful rays. I thought that clothing made from sun-protective material would provide more effective protection from the sun’s harmful rays than material that is not made specifically as sun protective clothing. I thought that non sun-protective material with optical brighteners would provide the most effective protection from the sun’s harmful rays.

I predicted that, after 19 washings, the sun protective material would provide more effective protection than either the non sun-protective with optical brighteners or the non sun-protective materials. My hypothesis was partially supported. At 19 washings, the sun-sensitive paper test showed that the sun-protective material provided the most effective protection against the sun’s harmful rays. However, both the spectrophotometer test and the light meter test indicated that the non sun-protective material with optical brighteners provided the most effective protection against the sun’s harmful rays.

I predicted that, after 25 washings, the non sun-protective material with optical brighteners would provide the most effective protection against the suns harmful rays, followed by the sun-protective, then the non sun-protective material. My hypothesis was partially supported. At 25 washings, the non sun protective material with optical brighteners provided the most effective protection against the sun’s harmful rays. Both the spectrophotometer and the light meter proved the sun-protective material to provide the most effective protection. After 25 washings, two out of three of the test indicated that the sun-protective material provided the most effective protection against the sun’s harmful rays.

Overall, the sun-protective material ranked number one more often than the non sun-protective material with optical brighteners, followed by the no sun-protective material.