What does the SPF number on your sun cream actually mean?

You probably assumed that the SPF number on sun cream means one thing: the higher the number, the more protection you have from the sun.

Well, you’re not wrong.

But the sun protection factor (SPF) number is actually a lot more helpful than that.

The figure tells you a specific amount of time before you will begin to burn.

Skin Cancer Foundation has summed up each factor very clearly. “If it takes 20 minutes for your unprotected skin to start turning red, using an SPF 15 sunscreen theoretically prevents reddening 15 times longer – about five hours,” the site says.

So an SPF 30 sun cream would prevent burning for 30 times longer and so on and so forth.

All you need to know is the amount of time you can stay in the sun unprotected before your skin starts to show signs of burning.

(Warning: perhaps go for an estimated figure rather than trying this out. You don’t want to end up like these guys.)

Skin Cancer Foundation also notes that “no sunscreen – regardless of strength – should be expected to stay effective longer than two hours without reapplication.”

Wise words to remember the next time the sun makes an appearance.

And remember: if you’re planning on getting in the pool or sea, reapply as soon as you get out to prevent any chance of burning.

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