A sunscreen with a protection factor of 30 allows you to stay in the sun without burning.

一种防护系数为30的防晒霜使你能够待在太阳底下而不被晒伤。

《柯林斯英汉双解大词典》

Use a broad-spectrum sunscreen of sun protection factor 15 +.

使用防晒指数15 +的广谱防晒霜。

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SPF is really sunburn protection factor, even though we call it sun protection factor.

SPF实际上是“防晒伤指数”，虽然我们常称它为“防晒指数”。

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Look for sunglasses with an eye-sun protection factor (E-SPF) between 25 and 50, he said.

WSJ: The Crucial Years for Protecting Your Eye Health

They weren't cancerous, but she began using a sun-protection factor of 45 as part of her daily routine.

WSJ: The Myths of Daily Sunscreen

The result is a material that is not only waterproof but is able to block out UV radiation from the sun to such an extent that it would rate a Ultraviolet Protection Factor (UPF) of 101.15 if the chart went that high.

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