SPF

abbreviation

1. sun protection factor: the effectiveness of a sunscreen in protecting the skin from the sun's ultraviolet UVB radiation, as rated on a scale of increasing protectiveness, the number being the ratio of the radiation dose needed to produce minimal redness when using sunscreen compared to the dose needed to produce the same redness without sunscreen.

   An SPF of 15 will allow you to stay in the sun 15 times longer.

SPF

¹

abbreviation

1. sender policy framework: a mechanism designed to prevent an e-mail address being duplicated and used as a false address from which to send unsolicited e-mails

2. sun protection factor: an indicator of how effectively a sun cream, lotion, cosmetic, etc, protects the skin from the harmful rays of the sun

   SPF 25

S.P.F.

²

abbreviation

1. vet science specific pathogen free; denoting animals specially bred to ensure that they are free of specified diseases

Example Sentences

Problems have been identified with both the manufacture of some sunscreens and the integrity of lab testing relied upon to prove their SPF claims.

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The group had tested 20 sunscreens in an independent accredited Australian lab, finding 16 did not meet the SPF, or skin protection factor, rating listed on the packet.

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“Always see your dermatologist if you see an irregularity that’s not going away. Don’t wait. And protect yourself — I like an SPF of 50 or greater and apply it 15 minutes before going outside.”

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Some active ingredients in human sun cream are toxic to pets so vets recommend using a pet-safe waterproof sunscreen, with an SPF rating of 30 or higher.

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Now he says he's frightened by the sun and lathers himself up in SPF before even thinking about stepping outdoors.

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