How do you shop for sunscreen when faced with the dizzying array of options on the drugstore shelf? You likely look to scent, feel and SPF level to distinguish between formulas. However, the biggest difference between sunscreens could be in the amount of protection the product truly offers, even if the SPF listed on one bottle is the same number as the tube next to it.

As a result, the F.D.A. has ushered in a new litany of regulations that attempts to clarify exactly what kind of coverage is in that bottle you’re buying. Chief among the new rules, sunscreens must now offer broad spectrum coverage of both UVA and UVB rays with at least an SPF of 15 in order to claim skin cancer and aging prevention. “Water/sweat proof” must be exchanged for “water/sweat resistant” (since no sunscreen is truly waterproof), and tested to either 40 or 80 minutes of undiluted wear in order to pass the test.

Love those travel-friendly SPF wipes? Sorry! Towelettes and wipes, in addition to shampoos, can no longer claim SPF protection, and sprays must submit data detailing effectiveness and safety against inhalation in order to qualify.

Yet the regulation most poised to change the industry is the proposal that manufacturers can no longer rate a sunscreen over SPF 50, which, if passed, would change how many brands label and market sun safety products.“There is not sufficient data to show that products with SPF values higher than 50 provide greater protection for users than products with SPF values of 50,” says F.D.A. spokesperson Shelly L. Burgess. The proposal is open for public comment at regulations.gov until September 15th, 2011, after which point the F.D.A. will review submitted data and come to a final ruling.

Many experts welcome the guidelines, which they say is long overdue in an industry where the race to claim higher and higher SPF numbers has misled many consumers to assume they’re receiving multiple times more protection, when the safety of their skin is actually at risk. “Anything over SPF 50 really affords no extra UVB protection, and only gives a false sense of security,” says New York dermatologist and YouBeauty Dermatology Advisor, Amy Wechsler, M.D.

READ MORE: Get Sunscreen Savvy

 There are some experts who say it’s still not enough. Even though broad spectrum protection now encompasses UVA rays, the level of that protection can still widely differ. Chicago dermatologist, Amy Taub, M.D., says some European countries implement more specific and effective systems.

“In the U.K. and Ireland, they have a star rating for UVA coverage, whereas the F.D.A. version is a pass/fail,” explains Taub. “It appears they chose this method for reasons of clarity, cost and the belief that the differences in these ratings aren’t truly significant in terms of risk for the average person. I would have preferred to have the star rating in addition to the SPF rating.”

Breaking down SPF numbers to such a detailed analysis may strike some as excessively nit-picky, but it’s those UVA rays that are the most dangerous aspect of sun exposure. Until now, these rays have tended to fly under the radar, as the damage isn’t immediately obvious, like what you see with a blistering sunburn.

“UVA is the one [ray] that dermatologists fear the most in the long term—it causes skin cancer as well as aging, and it’s sometimes even referred to as UVAging,” says Omaha, Nebraska dermatologist, Joel Schlessinger, M.D. “The proposed F.D.A. regulations are vague in the actual way they will address the question of just what exactly is ‘broad spectrum.’ It concerns me that there is quite a bit of difference in the standards for UVA protection at present, and there is the chance that in trying to fix the current system, a new set of issues will develop,” adds Schlessinger.

Also, as part of the rulings, not only will products with SPFs between 2 and 14 no longer be able to claim broad spectrum protection, but these items will have to print the following warning on the label: “Skin Cancer/Sun Aging Alert: Spending time in the sun increases your risk of skin cancer and early skin aging. This product has been shown only to help prevent sunburn, not skin cancer, or early skin aging.”

That statement is not necessarily true, says Maryland dermatologist, Noelle Sherber, M.D. “It’s interesting that no sunscreens under SPF 15 can make skin cancer or aging prevention claims, given that they would work as well as a higher SPF if applied sufficiently frequently. The F.D.A.’s assumption must be that people would not reapply,” she says. Lower SPF rated items like lip balms will no longer be able to make protection claims, despite the fact that most carry and reapply these products throughout the day.

Schlessinger agrees that products under SPF 15 should still be allowed into the approved protection range, saying that he even recommends low number sunscreens for certain patients. “There are times when it is better to have an SPF of 10 and formulate a product that a teenager will use, versus having an SPF of 15 or more, and have the sunscreen left at home while they go to the beach. Likewise, I still see value in a range over 50 in some cases and skin conditions, so that is a concern to me,” says Schlessinger.

So how are beauty brands who have banked on the premise of high SPF protection responding to the proposal? Marketing Director Deborah Boucher at Ocean Potion—where sunscreens can reach past SPF 70—says the brand has anticipated the new changes for several years, and has already made the transition from water/sweat proof labeling to water/sweat resistance. The brand is in line to comply with all the other new regulations by next summer.Meanwhile, Neutrogena, which stands prominently among the brands who claim the highest protection on the market at SPF 100, says that even though it has already adopted the F.D.A.’s UVA protection guidelines, it plans to put up a fight about the SPF 50+ proposal.

“While we support the F.D.A.’s efforts, we continue to believe that SPF products over 50 provide additional sun protection for consumers, and we have submitted data in support of our position. We believe that limiting labeling for SPF values higher than 50 may deter consumers from receiving the highest levels of sun protection,” says parent Johnson & Johnson Group of Consumer Companies in a statement.And that leaves you—the confused consumer. Experts say the most effective strategy for now is to look for both UVB and UVA protection on the label with an SPF of at least 30, and to apply the golf-ball sized amount it takes to truly deliver the promised protection. And while out frolicking in the sun, be sure to reapply every couple of hours. Consistency is key to optimal results.

READ MORE: 6 Ways to Outsmart the Sun