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The FDA 4-Star Rating System:The FDA plans to implement include a four-star rating system for UVA protection that would be based on both in vitro and in vivo tests and incorporate a measurement of photostability.
Manufacturers would be required to include the four-star rating on their sunscreen labels and would face new restrictions in what they can and cannot say on labels. For instance, the proposed guidelines would prohibit claims such as "chemical-free," "waterproof," "helps prevent skin damage," or any SPF designation greater than 50.
SPF would no longer stand for "Sun Protection Factor" but, rather, "Sunburn Protection Factor" to clarify its use as a measurement of only UVB, the rays responsible for sunburns but not the premature signs of aging or skin cancer, which is mostly attributed to UVA.
Source here.