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No matter how hot it is outside, it’s important to stay SunSmart when ultraviolet (UV) Index is three or above by remembering to slip, slop, slap, seek and slide! Don’t know the difference between SPF30+ and SPF50+? Our SunSmart team have all the facts.

SPF30 versus SPF50

The SPF (Sun Protection Factor) of a sunscreen is a measure of how well it protects the skin from sunburn. SPF30 sunscreen admits 1/30th of the ambient UV (ultraviolet) radiation, SPF50 admits 1/50th and so on. Sunscreens need to be applied liberally to achieve the SPF protection claimed on the label. No sunscreen will give 100% protection from UV radiation – it’s not a suit of armour!

We recommend using any sunscreen that is labelled broad spectrum, water-resistant and SPF30 or above.

Interestingly, SPF50 offers only marginally better protection from UV radiation than SPF30 filtering out 98 per cent of UV radiation compared to 96.7 per cent blocked by SPF30.

It’s important to consider how you apply sunscreen. SPF30 and SPF50 sunscreens still need to be applied  liberally, re-applied every two hours (or after swimming, exercising and towel drying) and used in combination with other measures including sun protective hats, protective clothing, sunglasses and shade. Follow the instructions on the packaging.

What do all the sunscreen terms mean?

  • Sun Protection Factor (SPF) is a measure of protection sunscreen gives against UVB radiation. The rating tells you how long the sun’s UV would take to redden your skin compared with using no sunscreen. For example, in theory SPF50 would take you 50 times longer to burn than if you use no sunscreen. In reality, we know that many Australians do not apply the right amount of sunscreen to achieve the SPF stated on the bottle, so correct application is key.
  • Water resistant: Sunscreens labelled as water resistant are tested to be effective for up to 40 minutes of swimming.
  • Broad-spectrum: Broad-spectrum sunscreens filter both UVA and UVB rays. UVB is the principal cause of sunburn and UVA is the main cause of wrinkles, thickened and blotchy skin. Both UVA and UVB contribute to increased skin cancer risk.
  • Use by and storage: Expired sunscreen may not be effective so check the ‘use by’ date before applying. Store sunscreen correctly – below 30°C and out of direct sunlight.
  • Broad-spectrum: Broad-spectrum sunscreens filter both UVA and UVB rays. UVB is the principal cause of sunburn and UVA is the main cause of wrinkles, thickened and blotchy skin. Both UVA and UVB contribute to increased skin cancer risk.
  • The ‘+’ sign: The plus sign means ‘more than’. SPF50+ sunscreen must provide at least SPF60 in testing. This is because the same batch of sunscreen will test slightly differently in different laboratories with different methodology. By testing at SPF60, it removes any margin for error.

Applying sunscreen

Apply a generous amount of sunscreen 20 minutes before you go outside and again every two hours.

The average-sized adult should apply one teaspoon of sunscreen to each arm and leg. The face/neck (including ears) and front and back of body should also get a teaspoon each. That is seven teaspoons in all or 35ml of sunscreen for one full body application.

Many Aussies apply too little sunscreen and forget to re-apply every two hours. This means they usually get less than half the protection stated on the product label. Sunscreen can be easily wiped off, lost through perspiration and is often applied unevenly in the first place. Putting on more sunscreen every two hours helps keep you protected. It’s important to remember to re-apply after swimming or water sports also.

The best sunscreen is the one that suits your skin type, activity and that you find easy to reapply. So try different products out until you find one you like. If you have an allergic reaction to a sunscreen, try another brand or look for a fragrance-free product such as a toddler or sensitive sunscreen. A doctor or chemist could also offer advice about choosing another product.

*Think UV, not heat

Many people mistakenly believe they only need sun protection on hot, sunny days. However, it is Ultraviolet (UV) radiation from the sun, not heat, that is the major cause of sunburn, premature ageing, eye damage and skin damage leading to skin cancer.

UV can’t be seen or felt. Because of this, it can be damaging without us knowing it at the time. The UV index tells us the strength of UV radiation each day. Sun protection is recommended when the UV index is three or higher. Often, the UV can be high on cool, cloudy days. A great way to keep track of the UV index where you are is via our free SunSmart app which can be downloaded here or by checking our myUV website.

Read more about how to be SunSmart on our myUV website.