The myths of sun protection
1. The difference of realistic and practical value applied on skin
The practical value is 2mg/ cm2 on skin during the experiment for sun block lotion. The realistic average consumption of sun block products is 0.5-1.25mg/ cm2 a day. That means needing to supply the lotion frequently to meet the experiment effect.
2. The effectiveness of higher SPF
According the testing, SPF 15 will protect 93% of sun light. SPF 30 will protect 96.66% of sun light. The sun protection factor is double, but the filter rate only increase a little. It shows not the expensive and higher sun protection factor always is best. Otherwise, the normal products can’t provide wide band protection due to UVA and UVB have different wave lengths. The shorter wave length has higher energy to penetrate the skin.
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