Measurement of UV protection afforded by sunscreens and clothing
| Measurement system
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SPF (Sun protection factor)
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UVA‐PF (UVA‐protection factor)
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UPF (Ultraviolet protection factor)
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| Definition
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| Developed for
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| Global acceptance
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| UV wavelengths protected
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| Examples
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- SPF 2 protects against 50% of UVB
- SPF 8 protects against 88% of UVB
- SPF 15 protects against 93% of UVB
- SPF 30 protects against 97% of UVB
- SPF 50 protects against 98% of UVB
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- UVA‐PF1 protects against 20–39% of UVA
- UVA‐PF2 protects against 40–69% of UVA
- UVA‐PF3 protects against 70–95% of UVA
- UVA‐PF4 protects against >95% of UVA
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Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Sara Mohsin, M.D.[2]
References