All things SPF
October 28, 2026
Sunscreen for Drivers: The Window Is the Problem
Windshields block 96% of UVA. Side windows block 71%, and some as little as 44%. Why drivers age one side of the...
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October 12, 2026
Sunscreen for Pilots: The Cockpit Is a UVA Problem
Cockpit windscreens block nearly all UVB and let a large share of UVA through, so pilots sit in UVA-heavy light with no...
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October 06, 2026
Mineral Sunscreen With Clean Ingredients: What That Word Is Hiding
Clean has no legal definition in sunscreen. What people mean by it, why fewer ingredients matters, and where the usual ones are...
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October 04, 2026
Zinc Oxide vs. Titanium Dioxide: Which Mineral Filter Does More
Titanium dioxide is the stronger UVB filter per unit and runs out above 350nm. Zinc oxide covers to about 380nm, so one...
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October 01, 2026
Denver UV Index by Month: Three Years of Data
Denver UV index by month, measured from 1,096 days of hourly data, plus why elevation, clear skies and snow push the numbers...
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September 24, 2026
Mineral Sunscreen for Kids: What to Look For, and How to Get It On Them
For kids six months and older, the best sunscreen is a broad spectrum mineral formula with zinc oxide, SPF 30 or higher,...
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September 23, 2026
Do You Need Sunscreen in Fall and Winter?
UVA, the ray that ages skin, stays steady all year and passes through clouds and windows. Snow and altitude add reflection. Here...
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September 16, 2026
Powder Sunscreen: Fine for Touch-Ups, Wrong for First Layer
Powder sunscreens are having a moment, and it is easy to see why. Brush one on over makeup, no greasy hands, no...
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September 15, 2026
UVA Is the Real Winter Sun Problem (the Damage You Never Feel)
Winter cuts UVB and the burn risk, but UVA barely changes. It passes through glass and clouds, it never burns, and it...
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