What is SPF?


Most of us know we need to protect our skin from the sun. However, understanding sun-care products can be difficult, which might mean you’re not getting the level of protection you need.

As well as using sunscreen, make sure you also protect your skin by wearing suitable clothing and sunglasses, and staying in the shade when the sun is at its hottest.

What’s the difference between UVA and UVB rays?

The sun emits two types of ultraviolet rays: UVA and UVB, and both are damaging to the skin. 

UVA rays

UVA rays account for up to 95% of the UV radiation that reaches the Earth's surface. 

Although less intense than UVB, UVA rays are more abundant and can penetrate both clouds and glass.

UVA rays also penetrate skin more deeply than UVB.

Tanning booths give out mostly UVA, with many sunbeds producing UVA doses higher than the midday sun in the Mediterranean.

Over-exposure to UVA can cause long-term damage, including skin cancer, and can also prematurely age the skin (photoaging).

UVB rays

These are mostly responsible for sunburn and skin reddening. They also play a part in the development of skin cancers. UVB is h2est at the height of summer, but you can burn all year round – especially at high altitude, where the atmosphere is thinner. 

You should always protect yourself if you're in snow or on ice – these surface conditions reflect up to 80% of the sun's rays, meaning they can hit the skin twice. UVB light is largely blocked by glass.

What is SPF?

SPF stands for Sun Protection Factor. This is a number indicating the level of protection a sun product provides against UVB rays. 

The SPF number indicates how long a product allows us to stay in the sun without burning. For example, if you have fair skin, and burn after 10 minutes with no protection, applying an SPF 15 sunscreen will protect you for 15 times that – so, 150 minutes. 

If you have darker skin, and burn after 20 minutes, the same product will protect you for 300 minutes.  SPFs range from 2 to 50+, with 50+ offering the most protection against UVB.

What are UVA star ratings?

Most sunscreens carry a UVA star rating, ranging from 0 to 5, with 5 providing the most protection. It's recommended that you use a sunscreen with at least a 4 star UVA rating. If the sunscreen has 'UVA' in a circle, this mark means it meets EU standards.

What SPF should I be using?

It's recommended you use a sunscreen with a minimum SPF of 15, along with a UVA rating of 4 or 5 stars. People with fair skin and children should use a sunscreen with an SPF of at least 30.

To stay protected throughout the day, it’s important to generously reapply sunscreen products every two hours, and after you've been in the water or sweating heavily. If they're applied too thinly, sunscreens are not fully effective. If you're in doubt, choose a product with a higher SPF to be on the safe side.

You can always check with your pharmacist if you're unsure about which product to use. Make sure you apply enough sunscreen to all exposed areas of the skin, including the face, neck and ears.

Next steps 

• Apply sunscreen generously and every two hours, or as often as recommended by the product

• Choose a sunscreen with a minimum SPF of 15 and a UVA star rating of 4

• Children and people with fair skin should use a sunscreen with a minimum SPF of 30

• Protect your skin against winter sun when at high altitude, or if you're in snow or ice