sun protection factor

noun

1. SPF.

sun protection factor

1. A measure, expressed numerically, of the degree to which a preparation containing sunscreen protects the skin from ultraviolet rays. The higher the value, the greater the level of protection from sun damage to the skin.

Word History and Origins

Origin of sun protection factor¹

First recorded in 1975–80

Example Sentences

Chemical sunscreen also allows for a higher SPF, or sun protection factor, which is a measure of how much UV radiation is needed to cause a sunburn on sunscreen-coated skin versus unprotected skin.

From Scientific American

Dermatologists recommend using a minimum sun protection factor of 30.

From New York Times

The recall includes all can sizes and all levels of sun protection factor, or SPF.

From Seattle Times

In a 1997 study, researchers instructed nine healthy people to apply sunscreen with a sun protection factor of at least 15 on their forearms, using the amount they would normally use.

From Washington Post

“We always say a sun screen with a sun protection factor, also known as SPF, of 30 is strong enough,” Khushalani said.

From Seattle Times