ALERT

Schedule your COVID-19 vaccination now! We are unable to accommodate walk-ins. Please do not call St. Luke's clinics directly about COVID vaccine scheduling. Unless you need to call for an emergency, please use myChart for questions and appointments. To ensure we're able to provide safe care in a safe environment for all patients, masks are required in all St. Luke's facilities, regardless of COVID-19 vaccination status. Learn more.
toggle mobile menu Menu
toggle search menu

Site Navigation

Supplemental

Menu

Sun protection factor (SPF)

Top of the page

Sun protection factor (SPF)

Sun protection factor (SPF) is a number on sunscreen labels that shows how long skin can be in the sun and maintain a low risk for sunburn. The higher the SPF number, the longer it protects a person from the sun's burning rays.

It is important to read the information on the sunscreen label about the SPF factor listed on the label and how much protection it gives the skin. The sunscreen should be applied according to the directions on the label so it is most effective in protecting the skin from the sun's ultraviolet rays.

No sunscreen gives total protection, but "broad-spectrum" sunscreens that contain ingredients such as avobenzone, benzophenones, cinnamates, salicylates, sulisobenzone, titanium dioxide, and zinc oxide usually protect from ultraviolet A and B (UVA and UVB) rays. The label of the sunscreen product will say what types of UV rays it protects the skin from.

Sweating heavily, swimming, or doing other water activities reduces the SPF because sweat or water on the skin will reduce the amount of protection the sunscreen provides. Sunscreen needs to be reapplied more frequently during these activities.

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. Healthwise is a URAC accredited health web site content provider. Privacy Policy. How this information was developed to help you make better health decisions.

To learn more, visit Healthwise.org

© 1995-2015 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.

Take Care, Someone Needs You.

You take care of others, so take care of yourself. Let us be your partner in health, whether you're recovering from an injury, checking in for your annual exam, or enjoying an online class.

Because when you take care of yourself, everyone around you benefits.

Quick Links
Connect with Us
Contact Us In Boise (208) 381-2222