Cancer Research UK : Sun protection

Sun protection - sunscreen

If you work outside use sunscreen on any exposed areas of skin

Then use factor 15+ sunscreen

There will always be times when we are out in the sun without adequate shade or cover-up clothing. This is when sunscreen is useful for protecting our exposed skin from the sun's rays. Sunscreen alone will not protect us completely from sun damage.

We should never use sunscreen in order to spend longer in the sun. It should be used to increase our protection.

Why factor 15+ sunscreen?

The Sun Protection Factor (SPF) of a sunscreen is a measure of its ability to filter out dangerous UVB rays. The higher the factor the more protection you get from burning. But higher factor sunscreens tend to be more expensive.

The reason experts recommend factor 15, is that this represents the best balance between protection and price. You will get over 90 per cent protection from UVB rays with SPF 15. Above SPF 30 you don't get much additional protection from higher factors.

No sunscreen - no matter how high the factor - can offer 100 per cent protection.

What is broad spectrum?

Broad spectrum sunscreens block out UVA rays as well as UVB.

There is no international measurement of UVA protection. In the UK we use the 'star' system. This system compares the ratio of protection from UVA with the protection from UVB. It ranges from 0 stars to 5 stars.

Because it is a ratio, the number of stars a product has is not an absolute measure. For example, an SPF 25 with 3 stars may screen out more UVA overall than an SPF 10 with 4 stars.

Buying sunscreen

Choose one:

with an SPF of 15 or above - this will give you over 90% protection
labelled 'broad spectrum' - to protect against UVA and UVB
that is water resistant - it is less likely to wash or be sweated off
with a valid 'use by' date - most sunscreens have a shelf life of 2-3 years
you can afford - you don't have to pay for expensive brands. All types are tested and the cheaper brands are just as effective if used properly.

Tips for using sunscreen properly

try to apply it 15-30 minutes before going out in the sun
apply to clean, dry skin and rub in only lightly
use generous amounts
re-apply once outside to ensure even coverage
then re-apply every 2 hours or more frequently if washed, rubbed or sweated off
never use it to spend longer in the sun - this will put you at risk of sun damage that could lead to skin cancer.

Do not store sunscreens in very hot places as extreme heat can ruin their protective chemicals.