SPF is a measure of how much solar energy (UV radiation) is required to produce sunburn on protected skin (i.e., in the presence of sunscreen) relative to the amount of solar energy required to...

防晒系数（SPF）是以具体数值表示产品防御中波紫外线的能力，是评价防晒化妆品保护皮肤避免发生日晒红斑/晒伤能力的防护指标。 SPF是防晒指数Sun Protection Factor的英文缩写，SPF值越大，防日晒红斑/晒伤效果越好。

2023年10月10日 · SPF stands for Sun Protection Factor. The SPF number indicates the level of protection against ultraviolet (UV) B rays. Sunscreens with a higher SPF offer greater protection from the sun.

SPF（Sun protection factor，防晒系数）是一个比值。 用日光模拟器模拟太阳光，以一定的剂量照射于皮肤，检测涂与未涂防晒的情况下，皮肤出现 最小红斑量（MED） 所需要的时间，其比值即为SPF。

Learn everything you need to know about SPF including how long factor 50 lasts, how it works and which number is best suited to your . What does the SPF number mean? The SPF number tells you how long it might take you to get burnt after applying it, versus not wearing any at all.

Sun Protection Factor (SPF) is a measure of a sunscreen's ability to prevent sunburn caused by ultraviolet (UV) B radiation. It tells you how much longer the skin with a sunscreen will be protected from sunburn than the skin without sunscreen. For example, an SPF 30 sunscreen theoretically provides 30 times more protection than no sunscreen.

2024年6月15日 · SPF, short for sun protection factor, represents how well a sunscreen protects against damage from the sun’s ultraviolet B (UVB) rays, which are responsible for sunburn...

2023年5月26日 · SPF (sun protection factor) is the scale based on the time it takes for "untanned skin to become red when exposed to UV light," says Glodny. For example, he says that a sunscreen with an SPF of 50 will "allow your skin to be exposed to the sun 50 times longer before it turned red compared to your skin without sunscreen."

SPF stands for “sun protection factor,” and represents how well a specific sunscreen protects against the sun’s harmful ultraviolet B (UVB) rays, which, according to the American Cancer …

SPF是防晒系数（Sun Protection Factor）的英文缩写，表示防晒品所能发挥的防晒效能的高低。 防晒系数是根据皮肤的最低红斑剂量来确定的。 皮肤在日晒后发红，医学上称为“红斑症”，这是皮肤对日晒作出的最轻微的反应。 最低红斑剂量，是皮肤出现 红斑的最短日晒时间。 SPF值后面的系数是指紫外线照对皮肤的照射不致伤害的一个时间范围。 一个SPF值代表肌肤未经任何防护时，能够晒多久而不被晒伤。 例如：在不涂防晒产品的情况下，在阳光下停留20分钟后，皮肤 …