Terminology can be tricky when it comes to sun protection, and with so many options out there, it’s important to be as educated of a consumer as possible. We’ve done the homework for you — below, the basics of what to look for and what to steer clear of, when prepping for your day(s) in the sun.

Broad is best. There are two kinds of potentially harmful ultraviolet radiation out there — UVA and UVB. The UVA rays are longer, and can cause long-term affects like wrinkles and other signs of aging, according to the Skin Cancer Foundation. UVB rays are shorter, and are the main cause of sunburn. Both can cause skin cancer. Broad-spectrum sunscreen protects from both types of rays. Know your numbers. SPF (Sun Protection Factor) is the measure of how long you can stay in the sun before UVB rays start to burn the skin. The American Academy of Dermatology recommends a rating of 30 or higher (though interestingly, there’s a strong case for maxing out at SPF 50). Make sure it’s going to stay on. You’ll want a water-resistant sunscreen — they’re labeled as effective for 40 or 80 minutes. Since no sunscreen is truly waterproof, the FDA has banned that term. Mineral vs. chemical. Active ingredients in sunscreens come by way of mineral or chemical filters. Mineral sunscreen uses zinc oxide and/or titanium dioxide for broad-spectrum coverage, and is the recommendation of the American Academy of Pediatrics. According to Dr. JJ Levenstein, “Mineral sunscreens are gentle, effective, immediately active after application, and are less likely to cause irritation or local allergic reactions.” To avoid. Vitamin A (also called retinal palmitate or retinol) is in 20 percent of all sunscreens, and has been linked to speeding the growth of tumors when applied in sunlight, according to the Environmental Working Group. Scary. Oxybenzone can disrupt the hormone system, and insect repellent should be purchased separately — not in a combination formula with sunscreen — and applied first.

As a reminder, babies under the age of 6 months should stay out of the sun entirely. If that’s not possible, Dr. JJ suggests covering the infant in lightweight, breathable clothing and using mineral sunscreen on exposed areas frequently.