DermUV

UV Protection for Hiking

UV increases ~10–12% per 1,000 m of elevation. Trail switchbacks, snow patches, and open ridgelines can double effective exposure.

Recommended gear

For hiking, DermUV recommends SPF 50+ and a reapply interval around 90 minutes, adjusted for sweat, water, and reflection.

Checklist

SPF 50+ broad-spectrum (sweat-resistant) Lightweight UPF 50 sun shirt + sun gloves Wide-brim hat or full-brim cap with neck cape Polarized UV400 sunglasses SPF 30 lip balm (lips burn fast and are easy to forget)

More activity guides

Compare this activity with other outdoor UV situations.

What to do with this UV Protection for Hiking data

Sunscreen labels are tested at 2 mg/cm². Typical real-world application is closer to half that, so DermUV assumes about half the labelled SPF when it estimates protected time.

The UV index is a measure of erythemal (skin-reddening) irradiance, where each whole point equals 25 mW/m² of UV energy reaching the surface. That is why burn-time estimates fall roughly by half when the index doubles.

Cumulative dose drives photoaging and long-term skin damage more than any single day. Small daily exposures on commutes, walks, and driving add up across a season.

Reapplication matters more than the SPF number. Reapply roughly every two hours outdoors and immediately after swimming, heavy sweating, or towelling, regardless of what the bottle claims.

Cloud cover is not protection. Thin or broken cloud can still pass most incoming UV, and light cloud edges can briefly scatter more UV toward the ground than a clear sky.

UV scale reference

The WHO scale groups UV 1-2 as low, 3-5 as moderate, 6-7 as high, 8-10 as very high, and 11 or above as extreme. Protection is recommended from UV 3 upward, and shade during the middle of the day becomes the priority from UV 8 upward.

A practical routine at moderate-to-high UV is roughly one ounce of broad-spectrum sunscreen for full-body coverage, applied 15 minutes before going out, then reapplied on schedule. Clothing, hats, and shade carry the rest of the load, especially for children and anyone with a history of easy burning.

Keep exploring DermUV

These pages give more depth around uv protection for hiking, from UV-scale reference material to definitions and city forecasts.

Numbers are modelled, not measured at your exact location, so treat them as guidance for planning rather than exact thresholds.