Look for the label “Broad Spectrum.” This means the product protects against both types of ultraviolet radiation: ultraviolet A (UVA) and ultraviolet B (UVB).

UVB rays are the main cause of sunburn. UVA rays can also cause sunburn. Both UVA and UVB cause skin cancer and premature skin aging. If the product is not labeled “Broad Spectrum,” it only protects against UVB.

You should also choose a product with a Sun Protection Factor (SPF) of 15 or greater. Most skin specialists strongly recommend an SPF of at least 30. The higher the number, the longer the UV protection lasts without reapplying.

If the SPF is less than 15, it will help lower the risk of sunburn for some. But in many people, it may not offer enough protection against sunburns, skin cancer and skin aging.

New rules demand that sunscreen labels also provide accurate information about:

• Whether the sunscreen is truly water resistant
• How often you need to reapply it
• Whether it protects immediately after you apply it