Sunscreen is a topical product such as lotion, spray, or gel, designed to protect human skin from UV radiation and sunburn.
Not all sunscreens are created equal. Some only protect from medium-wave UVB radiation but do not block long-wave UVA. Therefore it is important to look for “Broad Spectrum” sunscreens that protect from both types of UV light.
![](https://getsola.com/wp-content/uploads/2019/04/sola_max_uvdose-copy-4-2-558x1024.png)
Sunscreen products normally have an SPF number, which stands for Sun Protective Factor. It represents the effectiveness of the sunscreen in delaying sunburn.
![](https://getsola.com/wp-content/uploads/2019/04/sola_sunscreen-1-558x1024.png)
For example, if an individual’s skin normally develops a sunburn after 10 minutes of UV exposure, the same person wearing a sunscreen with SPF 30 under the same sunlight intensity will take 300 minutes to get a sunburn (10 minutes multiplied by a factor of 30 equals 300 minutes).
Sola pre-calculates your daily UV dose for each SPF option. If you don’t see a particular SPF number in the list, you can add one by using the “Add a custom SPF” textbox.
![](https://getsola.com/wp-content/uploads/2019/04/sola_custom_spf-558x1024.png)
You can also delete an SPF if you no longer need it by swiping the SPF cell to the left.
![](https://getsola.com/wp-content/uploads/2019/04/sola_delete_spf-558x1024.png)
As always, use your best judgement when choosing and using sunscreen products. And remember to apply sunscreen 15-30 minutes before going out in the sun for best results. You can set a reminder to re-apply sunscreen by using the “Remind to reapply sunscreen” stepper at the bottom of the screen.