The rays, known as UVA and UVB, come from sunlight. The second type, UVB, is the primary cause of skin cancer.
Every year, two million Americans are treated for the two most common forms of skin cancer: basal cell and squamous cell. Last year, more than 68,000 people were diagnosed with melanoma, the deadliest form of the disease.
Under the long-awaited regulations, for a sunscreen product to get the new designation "broad spectrum" protection it must have an SPF of 15 or higher, and may say on the label that it reduces the risk of skin cancer and early skin aging.
The FDA said any product that is not "broad spectrum" or has an SPF between 2 and 14 will be required to to have a warning that states the sunscreen has not been shown to help prevent skin cancer or premature skin aging.
Janet Woodcock, director of FDA's Center for Drug Evaluation and Research, said the use of terms like "sun block," "waterproof," and "sweatproof" will no longer be allowed on sunscreen packaging.
"These changes to sunscreen labels are an important part of helping consumers have the information they need so they can choose the right sun protection for themselves and their families," said Woodcock.
Instead, manufacturers are directed to label their products "water resistant" and state whether the sunscreen is effective for 40 minutes or 80 minutes. Those that are not "water resistant" must carry a warning for consumers if they are going to be exposed to either water or perspiration.
The FDA also proposed a new regulation that would limit the SPF value on sunscreens to 50 because there is no evidence any higher number provides more protection than 50.
The new information, which has been under consideration for the FDA for more than 30 years, must be on all sunscreen products by the summer of 2012.