If you can't avoid being in the sun, use a sunscreen to help protect your skin while you are in the sun.
Be sure to read the information on the sunscreen label about the SPF factor listed on the label and how much protection it gives your skin. Follow the directions on the label for applying the sunscreen so it is most effective in protecting your skin from the sun's ultraviolet rays.
Choosing a sunscreen
Sunscreens come in lotions, gels, creams, ointments, and sprays. Use a sunscreen that:
Says "broad-spectrum" that protects the skin from ultraviolet A and B (UVA and UVB) rays.
Use lip balm or cream that has SPF of 30 or higher to protect your lips from getting sunburned or developing cold sores.
Use a higher SPF at when you are near water, at higher elevations or in tropical climates. Sunscreen effectiveness is affected by the wind, humidity, and altitude.
Some sunscreens say they are water-resistant or waterproof and can protect for about 40 minutes in the sun if a person is doing a water activity.
Applying a sunscreen
Apply the sunscreen at least 30 minutes before going in the sun.
Apply sunscreen to all the skin that will be exposed to the sun, including the nose, ears, neck, scalp, and lips. Sunscreen needs to be applied evenly over the skin and in the amount recommended on the label. Most sunscreens are not completely effective because they are not applied correctly. It usually takes about 1 fl oz (30 mL) to cover an adult's body.
Apply sunscreen every 2 to 3 hours while in the sun and after swimming or sweating a lot. The SPF value decreases if a person sweats heavily or is in water, because water on the skin reduces the amount of protection the sunscreen provides. Wearing a T-shirt while swimming does not protect your skin unless sunscreen has also been applied to your skin under the T-shirt.